[Federal Register Volume 61, Number 170 (Friday, August 30, 1996)]
[Rules and Regulations]
[Pages 46026-46131]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-21289]
[[Page 46025]]
_______________________________________________________________________
Part II
Department of Labor
_______________________________________________________________________
Occupational Safety and Health Administration
_______________________________________________________________________
29 CFR Part 1926
Safety Standards for Scaffolds Used in the Construction Industry; Final
Rule
Federal Register / Vol. 61, No. 170 / Friday, August 30, 1996 / Rules
and Regulations
[[Page 46026]]
DEPARTMENT OF LABOR
Occupational Safety and Health Administration
29 CFR Part 1926
[Docket No. S-205]
RIN 1218-AA40
Safety Standards for Scaffolds Used in the Construction Industry
AGENCY: Occupational Safety and Health Administration, U.S. Department
of Labor.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: The Occupational Safety and Health Administration (OSHA)
hereby revises the construction industry safety standards which
regulate the design, construction, and use of scaffolds. The final rule
updates the existing scaffold standards and sets performance-oriented
criteria, where possible, to protect employees from scaffold-related
hazards such as falls, falling objects, structural instability,
electrocution and overloading.
In particular, the final rule has been updated to address types of
scaffolds--such as catenary scaffolds, step and trestle ladder
scaffolds, and multi-level suspended scaffolds--not covered by OSHA's
existing scaffold standards. In addition, the final rule allows
employers greater flexibility in the use of fall protection systems to
protect employees working on scaffolds and extends fall protection to
erectors and dismantlers of scaffolds to the extent feasible. Another
area that the final rule strengthens is training for workers using
scaffolds; the conditions under which such employees must be retrained
are also specified in the final rule. Finally, the language of the rule
has been simplified, duplicative and outdated provisions have been
eliminated, overlapping requirements have been consolidated, and the
performance orientation of the rule has been enhanced to allow
employers as much flexibility in compliance as is consistent with
employee protection.
DATES: Effective dates. This standard will become effective on November
29, 1996, except for Sec. 1926.453(a)(2), which will not become
effective until an Office of Management and Budget (OMB) Control number
is received and displayed for this ``collection of information'' in
accordance with the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et
seq.). OSHA will publish a document in the Federal Register announcing
the effective date of Sec. 1926.453(a)(2).
Incorporation by reference. The incorporations by reference of
certain publications listed in this final rule are approved by the
Director of the Federal Register as of November 29, 1996.
Compliance date: Employers are required to comply with the
provisions of paragraphs (e)(9) and (g)(2) of Sec. 1926.451, which
address safe access and fall protection, respectively, for employees
erecting and dismantling supported scaffolds starting on September 2,
1997.
Comments. Written comments on the paperwork requirements of this
final rule must be submitted on or before October 29, 1996.
ADDRESSES: In compliance with 28 U.S.C. 2112(a), the Agency designates
for receipt of petitions for review of the standard, the Associate
Solicitor for Occupational Safety and Health, Office of the Solicitor,
Room S-4004, U.S. Department of Labor, 200 Constitution Avenue, N.W.,
Washington, D.C. 20210.
Suggestions and information regarding the drafting of non-mandatory
Appendix B, ``Criteria for Determining the Feasibility of Providing
Fall Protection and Safe Access for Workers Erecting or Dismantling
Supported Scaffolds'' should be submitted to the Docket Officer, Docket
S-205, U.S. Department of Labor, Room N-2625, 200 Constitution Avenue,
NW., Washington, D.C. 20210.
FOR FURTHER INFORMATION CONTACT: Ms. Anne C. Cyr, Occupational Safety
and Health Administration, Office of Information and Public Affairs,
Room N-3647, U.S. Department of Labor, 200 Constitution Avenue, N.W.,
Washington, D.C. 20210, Telephone: (202) 219-8148.
SUPPLEMENTARY INFORMATION:
I. Background
Congress amended the Contract Work Hours Standards Act (40 U.S.C.
327 et seq.) in 1969 by adding a new section 107 (40 U.S.C. 333) to
provide employees in the construction industry with a safer work
environment and to reduce the frequency and severity of construction
accidents and injuries. The amendment, commonly known as the
Construction Safety Act (CSA), significantly strengthened employee
protection by authorizing the promulgation of construction safety and
health standards for employees of the building trades and construction
industry working on federal and federally-financed or federally-
assisted construction projects. Accordingly, the Secretary of Labor
issued Safety and Health Regulations for Construction in 29 CFR part
1518 (36 FR 7340, April 17, 1971).
The Occupational Safety and Health Act of 1970 (the OSH Act) (29
U.S.C. 651 et seq.) authorized the Secretary of Labor to adopt
established federal standards issued under other statutes, including
the CSA, as occupational safety and health standards. Accordingly, the
Secretary of Labor adopted the Construction Standards, which had been
issued under the CSA, as OSHA standards (36 FR 10466, May 29, 1971).
The Safety and Health Regulations for Construction were subsequently
redesignated as 29 CFR part 1926 (36 FR 25232, December 30, 1971).
Standards addressing scaffolds, Secs. 1926.451 and 1926.452, were
adopted in subpart L of part 1926 as OSHA standards as part of this
process.
Various amendments were made to subpart L during the first two
years of the OSH Act. The amendments revised scaffold provisions that
addressed planking grades, wood pole scaffold construction, overhead
protection, bracket scaffold loading, and plank spans. Also,
substantive provisions concerning pump jack scaffolds, height of catch
platforms, and guardrails were added (37 FR 25712, December 2, 1972).
Based on concerns regarding the effectiveness of the existing
scaffold standards, OSHA began a complete review of subpart L in 1977.
The Agency consulted the Advisory Committee on Construction Safety and
Health (ACCSH) several times regarding draft revisions to subpart L.
The transcripts of these meetings are part of the public record for
this rulemaking (Ex. 3-4). OSHA addresses specific recommendations from
the ACCSH, as well as those submitted by other rulemaking participants,
in the Summary and Explanation section, below.
On November 25, 1986, OSHA issued a notice of proposed rulemaking
(NPRM) on scaffolds used in construction (51 FR 42680). The proposal
set a period, ending February 23, 1987, during which interested parties
could submit written comments or request a hearing. The Agency twice
granted requests for more time to submit comments and hearing requests.
OSHA first extended the comment and hearing request period to June 1,
1987 (52 FR 5790, February 26, 1987) and then extended that period to
August 14, 1987 (52 FR 20616, June 2, 1987). OSHA received 602 comments
on the proposal, along with several hearing requests.
On January 26, 1988, OSHA announced that it would convene an
informal public hearing on March 22, 1988 to elicit additional
information on
[[Page 46027]]
specific issues related to scaffolds, fall protection and stairways and
ladders (53 FR 2048). The informal public hearing was held on March 22-
23, 1988, with Administrative Law Judge Joel Williams presiding. At the
close of the hearing, Judge Williams set a period, ending May 9, 1988,
for the submission of additional comments and information. OSHA
received 31 submissions, including testimony and documentary evidence,
in response to the hearing notice. On August 11, 1988, Judge Williams
certified the rulemaking record, including the hearing transcript and
all written submissions to the docket, thereby closing the record for
this proceeding.
In 1988, the American National Standards Institute (ANSI), an
organization which sets voluntary consensus standards, approved a
revision of ANSI A10.8-1977, Scaffolding, updating its safety
requirements for the use of scaffolds in construction and demolition
operations. Section 6(b)(8) of the OSH Act requires that when an OSHA
standard differs substantially from an existing national consensus
standard, the Secretary must publish ``a statement of the reasons why
the rule as adopted will better effectuate the purposes of the Act than
the national consensus standard.'' In compliance with that requirement,
OSHA has reviewed the requirements of this final rule with reference to
the corresponding provisions of ANSI A10.8-1988. The Agency discusses
the relationship between the provisions of subpart L and corresponding
provisions of ANSI A10.8-1988 in the Summary and Explanation, below.
On March 29, 1993, OSHA reopened the rulemaking record for subpart
L (58 FR 16509) to obtain additional comments and information regarding
fall protection and safe means of access for employees erecting and
dismantling scaffolds; the use of crossbraces in scaffold systems; and
the use of repair bracket scaffolds. The comment period was scheduled
to end on May 28, 1993. On May 26, 1993, the Agency extended the
comment period (58 FR 30131) to June 29, 1993, in response to a request
for additional time to submit comments. OSHA received 46 comments in
response to the March 29 notice. Those comments are discussed below in
relation to the pertinent provisions of the final rule.
On February 1, 1994, OSHA again reopened the rulemaking record (59
FR 4615) to obtain comments and information regarding scaffold
stairways; repair bracket scaffolds; tank builder scaffolds; a NIOSH
study of workplace fatalities; and scaffold-related material
incorporated from the proposed part 1910, subpart D rulemaking. The
comment period, which ended on March 18, 1994, elicited 46 comments.
Those comments are also discussed below in relation to the pertinent
provisions of the final rule.
A wide range of employers, businesses, labor unions, trade
associations, state governments, and other interested parties
contributed to the development of this record. OSHA appreciates these
efforts to help develop a rulemaking record that provides a sound basis
for the promulgation of revised subpart L.
Based on its review of existing subpart L, OSHA believes that
certain provisions in the existing standards are outdated, redundant,
or ambiguous. In addition, some types of scaffolds used in construction
(e.g., catenary scaffolds) are not clearly addressed by the existing
standards, and some provisions cover only certain types of scaffolds
when they should apply to all. The final rule eliminates those
unnecessary, outdated and redundant provisions (e.g., revised subpart L
states the requirement for guardrails once, rather than 19 separate
times as in the existing standard).
OSHA is coordinating the revision of part 1926, subpart L, with the
ongoing rulemakings initiated to revise the General Industry (part
1910, subpart D) and Shipyard (part 1915, subpart N) scaffold
standards, so that those standards will be consistent, where
appropriate.
II. Hazards Involved
Scaffold-related incidents resulting in injuries and fatalities
continue to occur despite the fact that OSHA has had a scaffold
standard (existing subpart L) in place since 1971 (Exs. 1, 2, 3, 42,
43, 44 and 45). However, the Agency believes that compliance with the
standard being published today will be better than it has been in the
past because this standard has been simplified, brought up to date, and
strengthened to provide additional protection.
Although specific accident ratios cannot be projected for the
estimated 3.6 million construction workers currently covered by subpart
L, the Economic Analysis that accompanies this final rule estimates
that, of the 510,500 injuries and illnesses that occur in the
construction industry annually, 9,750 are related to scaffolds. In
addition, of the estimated 924 occupational fatalities occurring
annually, at least 79 are associated with work on scaffolds.
OSHA prepared the following statistical estimates (based on 4.5
million construction workers then covered by subpart L) to support the
1986 proposal for subpart L, based on a review of accident data
prepared by the Bureau of Labor Statistics (BLS) (Ex. 3-1). The revised
scaffold standards contain a number of provisions designed specifically
to address the findings of this analysis.
a. Seventy-two percent of the workers injured in scaffold accidents
covered by the BLS study attributed the accident either to the planking
or support giving way, or to the employee slipping, or being struck by
a falling object. Plank slippage was the most commonly cited cause.
b. About 70 percent of the workers learned of the safety
requirements for installing work platforms, assembling scaffolds, and
inspecting scaffolds through on-the-job training. Approximately 25
percent had no training in these areas.
c. Only 33 percent of scaffolds were equipped with a guardrail.
The following are recent examples, from the OSHA Integrated
Management Information System (IMIS) data, of the types of accidents
that continue to injure and kill employees working on scaffolds.
In July, 1991, two employees were working on a pump jack
scaffold doing roofing work. The scaffold became overloaded and broke.
The employees fell 12 feet to the ground, resulting in one fatality and
one serious injury.
In August, 1992, two workers were erecting an aluminum
pump jack scaffold. As they were raising the second aluminum pole, the
pole apparently contacted an overhead power line. The pole being raised
was 29 feet 10 inches long and the line was 28 feet 10 inches high. The
line was approximately 11 feet from the house. One employee died and
the other suffered severe burns and was hospitalized. The surviving
employee noted that he thought they had enough room to work around the
power lines, which were not de-energized or shielded.
In July, 1993, a foreman climbed up the frame of a 45 foot
high tubular welded frame scaffold to check on an employee who was
sandblasting inside a stack at a steam plant. The scaffold was not
equipped with guardrails and there was no access ladder. After talking
to the employee, the foreman either fell from the unguarded platform or
fell while climbing down the scaffold end frame, resulting in his
death. There were no witnesses to the fall.
Based on its analysis of the available data and its field
experience in enforcing construction standards, the Agency has
determined that employees using scaffolds are exposed to a
[[Page 46028]]
significant risk of harm. Specifically, scaffold related fatalities
still account for approximately 9% of all fatalities in the
construction workplace. In addition, the above data indicate that the
revised final standard would have prevented many of these accidents
more effectively than compliance with the existing scaffold standards.
Consequently, OSHA finds that the revision of its scaffold standards
for construction is necessary to improve employee protection. OSHA has
determined that, as revised, the standard clearly states employers'
duties and the appropriate compliance measures.
For additional discussion of incidence rates, significance of risk,
and the protectiveness of the final rule, see Section IV, Summary of
the Final Economic Analysis.
III. Summary and Explanation of the Final Rule
The following discussion explains how the final rule corresponds to
or differs from the proposed scaffold standard and the existing
standard, and how the comments and testimony presented on each
provision influenced the drafting of the final rule. Except where
otherwise indicated, proposed provisions which did not elicit comment
have been promulgated as proposed, for reasons stated in the preamble
to the proposed rule which is hereby incorporated by reference (51 FR
42680).
Subpart L--Scaffolds. The title of subpart L of OSHA's Construction
standards has been changed from ``Scaffolding'' to ``Scaffolds'', as
proposed. The word ``scaffold'' is used in the title and throughout the
final rule in lieu of the longer word ``scaffolding.'' This change does
not affect the scope of subpart L. OSHA did not receive any comments
concerning the title of the subpart.
Section 1926.450 Scope, application and definitions applicable to
this subpart. Paragraph (a) of Sec. 1926.450 states the scope and
application of subpart L. The final rule will apply to all scaffolds
used in construction, alteration, repair (including painting and
decorating), and demolition operations covered under 29 CFR part 1926,
except that crane or derrick suspended personnel platforms will
continue to be regulated under Sec. 1926.550(g). Language explicitly
excluding these platforms has been added to the final rule. The
relationship between Sec. 1926.550(g), which covers these platforms,
and subpart L is discussed further in relation to Sec. 1926.451(c)(2)
and NPRM Issue 3, below. In addition, aerial lifts are covered
exclusively in Sec. 1926.453, as noted in paragraph (a) of
Sec. 1926.450. Proposed paragraph (a) covered all scaffolds.
A commenter (Ex. 2-38) recommended that OSHA explicitly exempt
personnel platforms suspended by cranes or derricks from this final
rule. The commenter stated ``[t]his would avoid confusion, both for the
Compliance Officer and the employer.'' As noted above, the Agency
recognizes the need for an exemption and has revised paragraph (a)
accordingly.
Another commenter (Ex. 2-18), representing the elevator industry,
suggested that OSHA revise the scope of proposed subpart L to exclude
``False cars used in elevator construction that are equipped with
independent safeties that operate on the guardrails * * *'' The
commenter supported the suggestion as follows: ``An elevator false car
operates on fixed guiderails * * * equipped with safeties that ride on
the guiderails * * * and are operated automatically by the slackening
of the hoisting rope. Past OSHRC (Occupational Safety and Health Review
Commission) decisions have recognized that a false car is a unique tool
and is not a scaffold.'' The commenter did not cite any specific OSHRC
decisions to support its assertion.
OSHA disagrees with this commenter on this point, because the
findings in two enforcement cases involving the Otis Elevator Company
(12 OSHRC 1470 and 12 OSHRC 1513 (1985)) clearly indicate that the
scaffold standards of subpart L cover false cars. In Otis Elevator
Company, 12 OSHRC 1513 (1985), the final order stated:
The evidence in this case showed that the false cars were used
as elevated working space from which employees installed permanent
elevator rails. The ability to raise and lower the false cars by
means of cables from overhead supports does not remove false cars
from the applicability of the scaffold standard, and a false car is
found to be a scaffold within the meaning of 29 CFR 1926.452(b)(27).
The Agency notes that elevator false cars fit the definition of a
``scaffold'' in final rule Sec. 1926.450(b) in that they are temporary
elevated work platforms used for supporting employees. Accordingly,
there are no apparent grounds for disputing that elevator false cars
are properly regulated under part 1926, subpart L. Therefore, OSHA will
continue to regulate temporary elevated work platforms, such as false
cars and go-devils used in elevator shaft construction, as scaffolds.
The Scaffolding, Shoring and Forming Institute (SSFI) (Ex. 2-367)
recommended that OSHA include ``Window cleaning'' within the scope of
subpart L, because ``[w]indow cleaning is a common activity that, for
the overwhelming majority of instances, uses transportable suspended
scaffolds.'' In addition, the Scaffold Industry Association (SIA) (Ex.
2-368) suggested that OSHA add ``scheduled and unscheduled maintenance
(including but not limited to painting and decorating, tuck pointing,
sand blasting, water proofing and window cleaning)'' to the scope of
subpart L, because maintenance is a type of work ``regularly performed
on scaffolds addressed in this subpart and, therefore, should be
included in the scope.''
Another commenter (Ex. 2-462) stated that expanding the scope of
subpart L to include maintenance would create confusion and ``would
greatly reduce the safety standard already in place for Powered
platforms for exterior building maintenance'' (29 CFR 1910.66).
The Agency is not expanding the scope to include building
maintenance because building maintenance (such as window cleaning) is a
general industry activity, addressed under the appropriate scaffold and
powered platform standards of 29 CFR part 1910.
OSHA received a general comment (Ex. 2-29) which noted that
Sec. 1910.66 addressed powered platforms used for exterior building
maintenance in general industry and urged OSHA to ensure that the
corresponding regulatory language in the construction standard for
scaffolds was consistent. As discussed above, the Agency agrees, and is
coordinating its General Industry, Shipyard and Construction rulemaking
activity so that employers in those industries have consistent
regulation, to the extent that workplace conditions permit.
Paragraph (b) of Sec. 1926.450 lists and defines all major terms
used in subpart L. Proposed terms and definitions which elicited no
comments and which have been promulgated unchanged or with only minor
editorial revisions are not addressed below. Those terms include
``adjustable suspension scaffold'', ``boatswains' chair'', ``body
belt'', ``body harness'', `` brace'', ``cleat'', ``coupler'',
``crawling board'', ``double pole scaffold'', ``exposed power lines'',
``fabricated decking and planking'', ``float (ship) scaffold'', ``form
scaffold'', ``hoist'', ``interior hung scaffold'', ``ladder stand'',
``lean-to scaffold'', ``lower level'', ``mobile scaffold'', ``multi-
level suspension scaffold'', ``multi-point adjustable scaffold'',
``open sides and edges'', ``overhand bricklaying'', ``platform'',
``pole scaffold'', ``pump jack scaffolds'', ``roof bracket scaffold'',
``runner'', ``self-
[[Page 46029]]
contained adjustable scaffold'', ``shore scaffold'', ``single-point
adjustable suspension scaffold'', ``single pole scaffold'', ``step
platform and trestle ladder scaffold'', ``stone setter multi-point
adjustable suspension scaffold'', ``supported scaffold'', ``suspension
scaffold'', ``tube and coupler scaffolds'', ``tubular welded frame
scaffold'', ``two-point suspension scaffold'', ``unstable objects'',
``vertical pickup'', ``walkway'', and ``window jack scaffold''.
As proposed, OSHA is revising its definitions for particular types
of scaffolds by specifying whether a particular type of scaffold is a
``supported'' or a ``suspension scaffold.'' OSHA believes that adding
this information will make it easier for employers to identify the
appropriate general requirements in final rule Sec. 1926.451.
In addition, the Agency has revised subpart L definitions by
deleting language that limits the use of a particular type of scaffold.
Such substantive limitations are more appropriately placed in
regulatory text. Accordingly, for example, OSHA has revised the
definition for ``bricklayers' square scaffolds'' (a scaffold composed
of framed wood squares which support a platform, limited to light and
medium duty) by deleting the words ``limited to light and medium
duty''. Similarly, OSHA has revised the definition for ``coupler'' to
be ``a device for locking together the component tubes of a tube and
coupler scaffold'', deleting language addressing the material used for
the coupler because such requirements are more properly located in
Secs. 1926.451 or 1926.452.
The following discussion covers the terms for which definitions are
being added or revised in this final rule and those proposed terms
which elicited comments.
``Bearer (Putlog).'' This definition is the same as the definition
proposed except that the word ``Putlog,'' an industry-used term, has
been added to the definition. A commenter (Ex. 2-29) suggested putlog
should be included in the proposed definition ``to show a close or
synonymous relationship to the term `bearer' '' and because ``it is a
widely used and understood term.'' The Agency agrees with the commenter
and has revised the proposed definition accordingly.
``Bricklayers' Square Scaffold'' is defined in existing
Sec. 1926.452(b) and the proposed definition is substantively unchanged
in the final rule. The definition deletes the existing Sec. 1926.452(b)
requirements that bricklayers' square scaffolds be constructed of
``wood'' and that the platform capacity be limited to ``light and
medium duty.'' The revised definition recognizes that bricklayers'
square scaffolds can be constructed of materials other than ``wood''
and that their capacity is not limited to ``light and medium duty'' as
long as they can meet the capacity requirements set forth in final rule
Sec. 1926.451(a)(1).
A commenter (Ex. 2-23) suggested that OSHA adopt the ANSI A10.8-
1977 definition for Bricklayers' Square Scaffold which specifies the
use of ``wood'' and the ability to sustain light to medium loads. As
stated above, OSHA believes it would be inappropriate to limit
technological advances that would provide for the use of other
materials with greater capacities. Therefore, the Agency has not made
the suggested revision.
``Carpenters' bracket scaffold.'' This term means a supported
scaffold consisting of a platform supported by brackets attached to
building or structural walls. The final rule is identical to the
proposal. The SIA (Ex. 2-368) suggested that because different trades
(i.e., cement finishers) use this type scaffold, the term be renamed
``bracket scaffold'' exclusively. OSHA recognizes that this type of
scaffold is used by several trade groups. However, OSHA believes that
it is widely recognized in the construction industry that ``carpenters'
bracket scaffolds'' are not used only by carpenters. Therefore, the
Agency is not making the suggested revision.
``Catenary scaffold.'' This type of scaffold is not specifically
addressed in OSHA's existing rule but is covered in final rule
Sec. 1926.452(r). This term refers to a suspension scaffold consisting
of a platform supported by two essentially horizontal and parallel
ropes which are secured to structural members and may be supported by
vertical pickups. The proposed definition has been changed to replace
the language ``fastened to'' with ``supported by'' and a phrase has
been added explaining that horizontal ropes ``may be supported by
vertical pickups.''
One commenter (Ex. 2-23) suggested that OSHA insert the word
``wire'' between the words ``parallel'' and ``rope.''
However, OSHA does not intend to restrict the type of material used
for suspension scaffold rope as long as it is ``capable of supporting
without failure six times the maximum intended load'' as set forth in
final rule Sec. 1926.451(a)(3).
Two commenters (Exs. 2-23 and 2-368) suggested OSHA replace the
words ``fastened to'' with ``supported by'' in this definition. OSHA
agrees that the suggested words more accurately describe the function
of the horizontal ropes with relation to the platform and is revising
the proposed definition accordingly.
In addition, the SIA (Ex. 2-368) suggested that OSHA add the phrase
``and may be supported by vertical pickups''. OSHA agrees with the
commenter. Vertical pick-ups can act as supports for sagging horizontal
ropes. Also, because final rule Sec. 1926.452(r)(1) refers to vertical
pickups, OSHA believes that it is appropriate to include this phrase in
the definitions.
``Chimney hoist.'' This term is being added to recognize a specific
type of multi-point adjustable suspension scaffold used to gain access
to worksites inside chimneys.
``Competent person.'' This term is being added to the final rule as
a matter of convenience for users. The definition is identical to that
found in Sec. 1926.32.
``Continuous run scaffold (run scaffold)'' means a two-point or
multi-point adjustable suspension scaffold constructed using a series
of interconnected braced scaffold members or supporting structures
erected to form a continuous scaffold. This term is being added to
recognize this type of system. The Agency notes that the key element
here is that the scaffold members must be interconnected so that the
erected scaffold acts as a single unit. This would preclude planking
across two independent scaffolds without joining them so the resulting
scaffold acts as one unit. This system allows erecting a lengthy
scaffold without requiring a continuous planked platform, as long as
the smaller platform is properly guarded.
``Deceleration device.'' This term means any mechanism, such as a
rope grab, rip stitch lanyard, specially-woven lanyard, tearing or
deforming lanyard, automatic self-retracting lifelines/lanyard, which
serves to dissipate a substantial amount of energy during a fall
arrest, or otherwise limits the energy imposed on an employee during
fall arrest. The proposed definition, which was effectively identical,
has been editorially revised for the sake of clarity.
Three commenters (Exs. 2-13, 2-368 and 2-516) suggested that rope
grabs and some self-retracting lifelines are not ``deceleration
devices'' but are actually fall arrest devices. OSHA notes, however,
that it is difficult to differentiate clearly between system
components, as suggested, because fall arrest (stopping) and energy
absorption (braking) are closely related. The Agency also observes that
the performance criteria for personal fall arrest equipment address the
entire system, not just ``fall arresters'' or
[[Page 46030]]
``energy absorbers''. Accordingly, OSHA has not made the suggested
change.
``Equivalent.'' This term is used in the final rule to allow
alternative means of complying with the standard. The definition
provides that the employer must be able to demonstrate that the
alternative means of compliance will provide an equal or greater degree
of safety than that attained by using the method or item specified in
the standard. The final definition is identical to the proposed
definition, except that minor editorial changes have been made for the
sake of clarity. The final rule definition is consistent with the
corresponding definitions in Sec. 1910.66 and in part 1926, subparts M
and X.
The SIA (Ex. 2-368) suggested that OSHA not require the employer to
``demonstrate whether or not the scaffold is of `equal or greater
degree of safety' because the employer is too many steps removed from
the manufacturer'' and because requiring the employer to test for
equivalency would create a significant danger that failure would occur.
However, the proposed language reflects the Agency's longstanding
position that employers who choose to deviate from criteria set in OSHA
standards must be able to demonstrate that employee protection has not
been adversely affected. The employer has the flexibility to establish
equivalence by any effective means, including information available
from equipment suppliers and taking into account the specific
circumstances of the work to be done.
``Eye'' or ``eye splice'' means a loop with or without a thimble at
the end of a wire rope. This term is being added to the final rule to
clarify the Agency's intent that this type of connection is an
acceptable way to connect wire ropes without significantly affecting
their strength or capacities. The term is used in final rule
Sec. 1926.451(d) (8) and (9).
``Fabricated frame scaffold'' means a supported or suspended frame
scaffold consisting of platform(s) supported on fabricated end frames
with integral posts, horizontal bearers, and intermediate members. This
is the term for the type of scaffold presently identified as ``tubular
welded frame scaffold.'' OSHA has determined that the current term is
too restrictive because the words ``tubular'' means round and
``welded'' means that metal components are involved. The provisions of
final rule Sec. 1926.452(c), Fabricated frame scaffolds, are not
subject to such limitations. They address fabricated frames and related
scaffold components whether the component parts are square or round, or
made of metal, plastic, wood, or some other material. The final rule
definition is identical to that in the proposed rule.
Two commenters (Exs. 2-13 and 2-320) suggested using the existing
term ``tubular welded frame'' and one commenter (Ex. 2-23) suggested
using the term ``Fabricated tubular frame (Tubular welded frame
scaffold)'' instead of the proposed term. However, as explained above,
OSHA does not intend to restrict this term to ``tubular'' or ``welded''
components.
``Failure.'' This term is used in performance-oriented paragraphs
such as Secs. 1926.451 (a)(1) and (a)(3), which address scaffold
capacity. Because the word might otherwise be interpreted to mean only
breakage or a physical separation of scaffold components, the final
rule definition clearly indicates that load refusal (the point where
the ultimate strength of a component is exceeded) is also considered to
be failure. This is the point where structural members lose their
ability to carry loads although they have not broken or separated. The
term is the same as the term defined in Subpart X of Part 1926, Ladders
and Stairways. The definition for ``failure'' in the final rule is the
same as proposed.
One commenter (Ex. 2-40) suggested that the term ``ultimate
strength'' was not clearly defined. Another commenter (Ex. 2-38)
suggested deleting the last sentence of the proposed definition (Load
refusal is the point where the ultimate strength is exceeded) to avoid
confusion between ``ultimate strength'' and ``overloading without
breaking.'' As OSHA stated above, ``ultimate strength'' may be exceeded
without component parts breaking or separating. Therefore, the Agency
believes the suggested changes are unnecessary.
``Guardrail system.'' This term refers to perimeter protection
composed of vertical barriers which are erected to prevent employees
from falling. The final rule definition is essentially identical to the
proposed definition. This term replaces the definition of ``guardrail''
in the existing rule, which appeared at Sec. 1926.452(b)(10). The old
definition was rail secured to uprights and erected along the exposed
sides and ends of platforms. OSHA believes that this definition did not
adequately reflect the manner in which toprails, midrails and other
intermediate members, and toeboards combine to provide effective fall
protection. The final rule definition of guardrail clearly indicates
that the entire system, including toprail, midrail (or other
intermediate protection), and uprights, is covered when guardrails are
addressed in final rule Sec. 1926.451(e). The definition of guardrail
system used in the proposed rule stated that a guardrail system was ``a
vertical barrier erected to prevent employees from falling from an open
side or edge of a scaffold platform or walkway''. The proposed
definition also distinguished between ``Type I guardrails'', which were
capable of providing fall protection without the use of personal fall
arrest systems, and ``Type II guardrails'', which would need to be
supplemented by personal fall arrest systems (as explained below, OSHA
has not maintained this distinction in the final rule).
The SIA (Ex. 2-368) suggested replacing the word ``prevent'' with
the word ``protect'' in the proposed definition of ``guardrail
system''. According to standard dictionary meanings of both words,
``prevent'' more accurately describes the function of the guardrail
system, which is to keep the employee from going past the perimeter of
the scaffold in the first place. Therefore, the Agency is not making
the suggested change.
Three commenters (Exs. 2-13, 2-53 and 2-370) recommended that OSHA
retain the guardrail rules in the existing scaffold standard and
eliminate the concept of ``Type I'' and ``Type II'' from the proposed
definition of guardrail systems. The commenters suggested that the old
rule's definition of guardrail protection would provide more fall
protection than the definition used in the proposed rule. For reasons
discussed further below, OSHA finds that the final rule's requirements
for guardrail systems, which are essentially identical to those in the
proposed rule, provide more protection than the requirements in the
existing rule. However, OSHA has deleted the discussion of ``Type I''
and ``Type II'' guardrails from the final rule for the sake of clarity
and has added specific criteria for guardrails to final rule
Sec. 1926.451(g).
``Horse scaffold'' means a supported scaffold consisting of a
platform supported by construction horses. Horse scaffolds made of
metal are sometimes known as trestle scaffolds. The proposed definition
was similar except that it did not include the term ``trestle
scaffold.'' The SIA (Ex. 2-368) suggested revising the definition to
specify that horse scaffolds ``may be constructed of wood, metal, or a
combination of both. The metal horses may be referred to as `trestle
horses'.'' Under OSHA's performance-oriented approach to subpart L, an
employer may use any construction materials (e.g., wood or metal) that
enable the scaffold to comply with the capacity requirement set forth
in Sec. 1926.451(a)(1). However,
[[Page 46031]]
the Agency agrees that it would be useful to indicate that some horse
scaffolds constructed of metal are known as trestle scaffolds. OSHA has
revised the definition accordingly.
``Ladder jack scaffold.'' The final rule definition, which is
identical to that in the proposed rule, states that this type of
scaffold is a supported scaffold consisting of a platform supported by
brackets attached to ladders.
A commenter (Ex. 2-23) stated that the capacity of this type of
scaffold should be limited to ``light duty'' and that the words ``light
duty'' should be included in this definition. As discussed above, OSHA
believes it is inappropriate for definitions to include substantive
requirements. In any event, the Agency has determined that a ladder
jack scaffold which complies with the capacity criteria of
Sec. 1926.451(a)(1) and the other pertinent subpart L requirements will
be considered acceptable. Accordingly, OSHA has not made the suggested
change.
``Landing.'' This new term, which has been added to ensure that the
requirements of final rule Sec. 1926.451(e)(4) are clearly understood,
refers to a platform at the end of a flight of stairs.
``Large area scaffold'' means a pole scaffold, tube and coupler
scaffold, systems scaffold, or fabricated frame scaffold erected over
substantially the entire work area, for example; A scaffold erected
over the entire floor area of a room. The Agency has added this term
and definition, along with final rule Sec. 1926.452(d), to provide a
reference point in the standard for this widely used type of scaffold.
``Lifeline'' means a component consisting of a flexible line for
connection to an anchorage at one end to hang vertically (vertical
lifeline) or for connection to anchorages at both ends to stretch
horizontally (horizontal lifeline), and which serves as a means for
connecting other components of a personal fall arrest system to the
anchorage. A vertical lifeline is sometimes known as a dropline. A
horizontal lifeline is sometimes known as a trolley line. This
definition, which was not part of the proposed rule, has been added for
the sake of clarity. The definition in part 1926, subpart M, Fall
Protection, is consistent with the definition in final subpart L. The
proposed terms ``dropline'' and ``trolley line'', along with their
definitions, have been deleted as separate definitions and have been
incorporated into this final rule definition.
One commenter (Ex. 2-57) stated that a ``trolley line'' was a
``horizontal lifeline'' and suggested that OSHA set ``strength
requirements.'' While final rule subpart L does not set numerical load
requirements for ``horizontal lifelines'', criteria for such equipment
are provided in Sec. 1926.502(d), subpart M, as referenced by a note to
final rule Sec. 1926.451(g)(3).
``Masons' adjustable supported scaffold.'' OSHA proposed this term,
which was not defined in existing subpart L, so employers who used
``self-contained adjustable scaffolds'' in masonry operations would
have a clear reference point in revised subpart L. The final rule is
identical to the proposed rule definition.
One commenter (Ex. 2-23) suggested replacing the parenthetical
reference to self contained adjustable scaffolds with the definition
for such scaffolds in ANSI A10.8-1977. However, to limit redundancy and
confusion, OSHA does not believe that this term should be defined by
the format suggested by the commenter.
``Masons' multi-point adjustable suspension scaffold.'' This term
replaces the term ``Masons' adjustable multiple-point suspension
scaffold'' in the existing standard. The term means a two-point or
multi-point adjustable suspension scaffold designed and used for
masonry operations. The final rule definition is the same as that
proposed.
One commenter (Ex. 2-23) suggested OSHA adopt the definition for
this term from ANSI A10.8-1977, which contains the language
``continuous platform.'' However, it is not OSHA's intent to limit this
type of scaffold to a single ``continuous platform.'' All types of
multi-point suspension scaffolds covered by subpart L may consist of
more than one platform. Multi-point scaffolds are not limited by the
number of suspension wires, platforms, or the location of attachment of
the suspension wires to the platform or platforms (Example: A multi-
point scaffold may consist of one platform suspended by four wires or
it may consist of two platforms suspended by four wires). Additionally
the definition suggested by the commenter did not include the words
``masonry operations.'' OSHA is including the words ``masonry
operations'' in this definition so it applies specifically to such
scaffolds used in the masonry trade.
``Maximum intended load'' means the total load of all persons,
equipment, tools, materials, transmitted loads, and other loads
reasonably anticipated to be applied to a scaffold or scaffold
component at any one time. This term replaces the existing terms
``maximum rated load'' and ``workload''. The term addresses the types
of loads which are to be included when determining the maximum load.
OSHA has been concerned that the word ``rated'' in the existing term
``maximum rated load'' does not clearly express how the safety factor
of four (existing rule paragraph 1926.451(a)(7)) or six (existing rule
paragraph 1926.451(a)(2)) is to be incorporated into the determination
of the maximum load. The final rule definition and final rule
Sec. 1926.451(a)(1) clearly indicate that the maximum intended load is
determined without regard to safety factors. Once the maximum intended
load is determined, the employer then applies the pertinent safety
factor to determine the requisite strength for the system in question.
The final rule definition is the same as in the proposed rule
except the word ``employees'' has been replaced with the word
``persons''. The SIA (Ex. 2-368) suggested this change because
``[p]ersons other than employees might be on a scaffold thus
overloading it.'' OSHA agrees that the weight of all ``persons'' needs
to be considered when calculating the maximum intended load.
One commenter (Ex. 2-23) suggested that OSHA add the closely
related term ``scaffold load rating'' which includes definitions for
the words ``heavy-duty loading,'' ``medium-duty loading,'' ``light-duty
loading'' and ``special loading.'' The Agency provides examples of
appropriate measures for ``heavy-duty,'' ``medium-duty'' and ``light-
duty'' scaffold in non-mandatory Appendix A of final rule subpart L.
Accordingly, the Agency believes the appropriate information is
available and no further changes are necessary.
Two comments (Exs. 2-13 and 2-320) suggested replacing the proposed
term and definition of maximum intended load with the term ``Maximum
Rated Load.'' The commenters suggested that the term ``Maximum Rated
Load'' takes into account safety factors established by the designer or
manufacturer.
OSHA agrees that the term ``Maximum Rated Load'' does include
built-in safety factors. As stated above, by not including the words
``safety factor'' in this definition or replacing the proposed term
with ``Maximum Rated Load,'' which implies built-in safety factors,
OSHA clearly indicates that the minimum safety factor of 4:1 as set
forth in final rule Sec. 1926.451(a)(1) applies. The Agency believes it
is appropriate to take into account the ``expected'' burden as well as
the burden a scaffold ``can'' support without failure.
``Needle beam scaffold'' means a suspension scaffold supported by
needle beams. The final rule definition is the same as the proposed
definition. One commenter (Ex. 2-23) suggested
[[Page 46032]]
that OSHA limit the use of this type of scaffold to ``light-duty''.
However, as discussed earlier, the Agency does not intend to limit the
capacity of a scaffold as long as it meets the pertinent requirements
of Sec. 1926.451(a). OSHA has provided examples of measures that would
enable a scaffold to comply with these requirements in non-mandatory
Appendix A.
``Outrigger.'' This term means the structural member of a supported
scaffold used to increase the base width of a scaffold in order to
provide support and stability for the scaffold. The terms, ``outrigger
beam'' and ``outrigger scaffold'' are new definitions provided to
explain the difference between these three similar terms. The final
rule differs from the proposal, which defined outrigger as ``the
structural member of a supported scaffold used to increase the base
width of a scaffold in order to provide greater stability for the
scaffold.'' The wording change was made in response to a comment from
the SIA (Ex. 2-368), suggesting that OSHA replace the word ``greater''
with the words ``support and increased.'' OSHA agrees that the
suggested wording more accurately expresses the Agency's intent.
``Personal fall arrest system.'' This term, which replaces the
proposed term ``body belt/harness system'', refers to a system used to
arrest the fall of an employee from a working level. It consists of an
anchorage, connectors, and a body belt or body harness and may include
a lanyard, deceleration device, lifeline, or suitable combinations of
these. The final rules on fall protection (part 1926, subpart M) and
powered platforms (Sec. 1910.66) also define ``personal fall arrest
system'' in this manner. The final rule definition is essentially the
same as that proposed for ``body belt/harness systems'', and the phrase
``personal fall arrest systems'' appears in the final rule wherever the
phase ``body belt/harness systems'' was used in the proposed rule. A
commenter (Ex. 2-13) suggested that the definition be reworded to
indicate clearly that lifelines and deceleration devices are not always
included as a part of a body belt/harness system. OSHA agrees and has
clarified this point in the revised definition.
OSHA has deleted the proposed term ``platform unit'' and has
incorporated the proposed definition language into final rule
Sec. 1926.451(b)(1)(i), which addresses the construction of scaffold
platforms.
``Power operated hoists.'' This new term refers to hoists which are
powered by other than human energy. The final rule language differs
from the proposed language, which used the term ``mechanically-powered
hoists''. OSHA has revised the terms ``mechanically powered'' and
``manually powered'' hoists to read ``power operated hoists and
manually operated hoists'', because the Agency has determined that the
language should be consistent with ANSI A10.8-1988, paragraph 6.
``Qualified.'' This term is being added to the final rule as a
matter of convenience for users. The definition is identical to that
found in Sec. 1926.32.
``Rated load.'' This new term addresses the maximum load that a
hoist is allowed to lift. The discussion of final rule
Sec. 1926.451(a)(1), below, addresses the use of this term.
``Repair bracket scaffold.'' This new term has been added to
address the type of scaffold addressed by final rule Sec. 1926.452(x).
This term is discussed below in conjunction with the discussion of that
paragraph.
``Scaffold.'' This term refers to a temporary elevated platform
(supported or suspended) and its supporting structure, including points
of anchorage, used for supporting employees or materials or both. The
definition also clearly indicates that crane or derrick suspended
personnel platforms are not scaffolds. The Agency has added the phrase
``including points of anchorage'' to the definition of scaffold in the
final rule to indicate clearly that points of anchorage are considered
to be part of a scaffold.
``Stair tower (Scaffold stairway/tower).'' This new term has been
added to describe the means of access addressed by final rule
Sec. 1926.451(e)(4). This term is addressed in relation to that
provision below.
``Stall load.'' This new term has been added to identify the
maximum load that a hoist can lift without stalling or shutting down.
The use of this term is discussed in relation to final rule
Sec. 1926.451(a)(2), below.
``Stilts'' mean a pair of poles or similar supports with raised
footrests, used to permit walking above the ground or working surface.
This term and definition has been added to recognize this type of
scaffold, which is used by many trades in the construction industry to
allow employees to walk elevated above the ground or working surface.
Final rule paragraph Sec. 1926.452(y) addresses the safe use of this
type of scaffold both as a scaffold itself, and on other types of
scaffolds (large area scaffolds).
``System scaffold'' means a scaffold consisting of posts with fixed
connection points that accept runners, bearers, and diagonals that can
be interconnected at predetermined levels. This new term has been added
to the final rule to recognize the existence and acceptance of this
type of scaffold. The definition is identical to the definition for the
same term found in ANSI A10.8-1988.
``Tank builders' scaffold'' means a supported scaffold consisting
of a platform supported by brackets that are either directly attached
to a cylindrical tank or are attached to devices that are attached to
such a tank. In the February 1, 1994 notice of record reopening (59 FR
4618), OSHA suggested a definition of ``tank builders' scaffold'' for
consideration. That definition was very similar to the final rule
definition except that the reopening notice definition did not
specifically refer to cylindrical tanks and did specify that the
platform was welded to the steel plates of the tank.
The commenters (Exs. 43-19, 43-23, 43-33, 43-34, 43-35, 43-39, 43-
40, 43-42, and 43-43) who responded to the proposed definition for tank
builders' scaffold stated:
A ``tank'' is not necessarily a cylinder. The scaffold is used
on structures that can be cylindrical, rectangular, conical,
spherical, spheroidal, or elliptical. Also, ``tanks'' are
constructed of material other than metal; e.g., fiberglass, wood,
etc. Some tanks have vertical walls that are so thin that a bracket
could not be welded to it; rather, the bracket would have to be
bolted. We would further comment that the bracket is often inserted
into a device which is welded to the steel plate. So we would
suggest not referencing the bracket being attached to the structure,
but rather the bracket being attached to a device that is affixed to
the structure.
In addition, eleven commenters (Exs. 43-19, 43-21, 43-23, 43-27,
43-33, 43-34, 43-35, 43-39, 43-40, 43-42, and 43-43) stated that the
criteria of an April 4, 1975 variance (40 FR 15139), which addressed
tank builder scaffolds, would be adequately addressed by general
provisions of the final rule and the definition of ``tank builders'
scaffold''.
The 1975 variance order stated:
The applicants' business, which is part of the tank building
industry, involves the erection of relatively large steel plate
segments of circumferential rings. Due to the unique nature of the
construction involved, special procedures, including special
scaffolding, have been developed. For example, as opposed to more
conventional scaffolds, tank scaffolds must be highly portable and
have a relatively low density of occupancy by [workers]. These
scaffolds are raised up the shell of the tank as new rings of steel
are added and work is completed at the level below.
Most plate structures are fabricated from standard length plates
* * * each approximately 31.416 feet (9.42 m.) long, [with] brackets
[normally] welded to them while they are on the ground prior to
being
[[Page 46033]]
placed into position on the tank wall. Scaffolding and guardrail
supports are then attached to these brackets. If the applicants were
to comply with [requirements] that [the maximum spacing for supports
be no more than 8 feet (2.4 m.) for guardrails or 10 feet (3.0 m.)
for planking], they assert it would be necessary to lay out each
steel plate into sections with the brackets located approximately
7.854 feet (2.36 m.) apart. Instead, the applicants wish to lay out
the plates into three equal sections with brackets located
approximately 10' 6'' (3.15 m.) apart.
* * * Because the contour of the steel plates of the tank face
is curved and the adjacent edge of the scaffold platform is
straight, there is an open space between them. As a result,
applicants have installed taut wire rope on the scaffold brackets
that extends midway between the innermost edge of the scaffold
platform and the curved plate structure of the tank face to serve as
a safety line in lieu of an inner guardrail assembly.
Since the information submitted to OSHA in relation to the variance
addressed scaffolds used on cylindrical steel tanks, the Agency is
applying the criteria of the variance only to structures that are
approximately cylindrical. The Agency believes that non-cylindrical
structures should be addressed on a case-by-case basis under the
general provisions of the final rule. OSHA notes that 9 of the 11
commenters (Exs. 43-19, 43-23, 43-33, 43-34, 43-35, 43-39, 43-40, 43-
42, and 43-43) mentioned above also stated ``[t]ank builders place the
scaffold inside of a cylinder, traditionally, to erect the tank.''
However, the Agency believes that the requirements of the variance, as
modified in Appendix A of the final rule, can reasonably be applied to
cylindrical tanks that are constructed of materials other than steel.
The final rule definition for ``tank builders' scaffold'' has been
worded accordingly.
OSHA has not promulgated specific requirements for tank builders'
scaffolds in the final rule because the Agency believes that the
requirements for those scaffolds are adequately addressed in the
general provisions of the final rule. The Agency notes that it has
placed several provisions (some of which have been editorially
modified) of the variance in Appendix A for the benefit of employers
who use tank builders' scaffolds, and that the introductory text to the
Appendix clearly indicates that following the Appendix will be
considered to constitute compliance with the requirements of this
standard with regard to scaffolds used in the construction of
cylindrical tanks. However, employers choosing not to follow the
Appendix must still comply with the applicable requirements of
Sec. 1926.451, particularly paragraphs (a) and (f).
``Top plate bracket scaffold.'' This term is being added to the
final rule to recognize a type of scaffold which is similar to
carpenters' bracket scaffolds and form scaffolds. This type of scaffold
consists of a platform supported by brackets that hook over or are
attached to the top plate of a wall. Such scaffolds are used in
residential construction when employees are setting roof trusses.
OSHA has deleted the following terms, which are defined in the old
scaffold standard, from the definition section of the final rule,
because those terms are now defined in other subparts or because the
final rule no longer uses the terms in question: ``heavy duty
scaffold,'' ``light duty scaffold,'' ``medium duty scaffold,''
``midrail,'' ``toeboard,'' and ``working load.'' In addition, the
proposed definitions for ``drop lines'', and ``trolley line'' have been
deleted from this final rule, since they have been incorporated into
the definition of ``lifeline''.
Under Issue L-12 in the preamble of the proposed rule, OSHA
solicited testimony and related information on a suggestion by the
ACCSH (Tr. 206, 6-9-87) that definitions for ``ramp'' and ``runway'' be
added to the standard. The ACCSH indicated that the added definitions
would facilitate clear understanding of the requirements in proposed
Sec. 1926.451(c)(4) (final rule Sec. 1926.451(e)(4)). As noted under
the discussion of the Issue, a member of the ACCSH recommended that the
Agency use the definition of ramp developed by the National Safety
Council.
The one comment (Ex. 2-593) OSHA received addressing the Issue
supported defining the two terms. The commenter did not provide any
suggested wording but indicated that the definitions should be ``clear
and consistent with existing OSHA and ANSI definitions.''
In the final rule, OSHA has replaced the proposed term ``runway''
with the term ``walkway'', to indicate the Agency's regulatory intent
clearly . However, the Agency believes that ``ramp'' is a commonly
understood term and does not require a specific OSHA definition.
Accordingly, OSHA has not added a definition for ``ramp'' to the final
rule.
Paragraph 1926.451(a) Capacity
Final rule paragraph (a) sets the minimum strength criteria for all
scaffold components and connections. The final rule sets scaffold
capacity requirements that are substantively the same as those in
existing subpart L, while eliminating ambiguities and apparent
inconsistencies. The introductory text of the proposed paragraph, which
stated that ``the following requirements applied to all types of
scaffolds except as indicated:'', has been deleted in the final rule
because the Agency has determined that it is too similar to the
introductory text of paragraph (a)(1) and, therefore, is unnecessary.
Paragraph (a)(1) requires that each scaffold and scaffold component
be capable of supporting, without failure, its own weight and at least
4 times the maximum intended load applied or transmitted to it.
Paragraphs (a)(2), (a)(3), (a)(4), (a)(5) and (g) of Sec. 1926.451
provide exceptions to this general rule, and are discussed below. This
provision is based on existing Sec. 1926.451(a)(7), which requires that
scaffolds and scaffold components ``be capable of supporting without
failure at least four times the maximum intended load''.
The final rule clearly provides that the 4 to 1 factor for a
component applies only to the load which is actually applied or
transmitted to that component, and not to the total load placed on the
scaffold. Existing Sec. 1926.451(a)(7), taken literally, could be read
to require that each separate scaffold component be able to support
four times the maximum intended load (MIL) of the entire scaffold. For
example, the existing provision could be interpreted to require that a
crossbrace on a supported scaffold be capable of supporting the same
load as a scaffold leg, that is, be sized to support four times the
entire MIL regardless of where the load is placed on the scaffold and
regardless of the fact that the function of a brace is to prevent sway
and not directly to support the MIL. Such an approach was not OSHA's
intent. The Agency intended that each component be adequate to meet the
4 to 1 factor, but only for the portion of the MIL applied or
transmitted to that component. The MIL for each component depends on
the type and configuration of the scaffold system. Final rule paragraph
(a)(1), which is effectively identical to the corresponding language in
proposed paragraph (a)(1), clearly expresses the Agency's intent. The
proposed provision has been editorially revised and reorganized for the
sake of clarity. In particular, the exceptions to proposed paragraph
(a)(1), which provide different coverage for suspension scaffolds, have
been clearly delineated as separate paragraphs (a)(2) through (a)(6) in
the final rule.
Paragraph (a)(2) of the final rule requires that direct connections
to roofs and floors and counterweights used to balance adjustable
suspension scaffolds be capable of resisting at least 4 times the
tipping moment imposed by the scaffold operating at either the rated
[[Page 46034]]
load of the hoist or at 1.5 (minimum) times the tipping moment imposed
by the scaffold operating at the stall load of the hoist, whichever is
greater. Proposed paragraph (a)(2) simply required that direct
connections to roofs and floors, and counterweights used to support
suspension scaffolds, be capable of providing a resisting moment of at
least four times the tipping moment. The proposed provision was
intended to clarify that the safety factor of four to one also applies
to direct connections to floors and roofs and to counterweight systems.
These areas are as integral to the scaffold system as the scaffold
platform itself. OSHA has revised the proposed provision to account for
the need to base the factor of safety for adjustable suspension
scaffolds on the rated load of the hoist and the stall load of the
hoist.
Several commenters (Exs. 2-8, 2-28, 2-64, 2-367, and 2-516)
indicated that the factors of safety for adjustable suspension
scaffolds should be based on the rated load of the hoist. Four of those
commenters (Exs. 2-28, 2-64, 2-367 and 2-516) and the SIA (Ex. 2-368)
recommended that the stall capacity of the hoist be considered in the
factors of safety.
One of these commenters (Ex. 2-28) stated that many suspended
scaffolds are rigged by inexperienced persons who do not realize that
if the scaffold catches on an obstruction, the maximum lifting power
(stall load) of the hoist can be developed and transmitted to the
counterweights and anchorages. This commenter suggested adding one of
the following requirements to proposed Sec. 1926.451(a)(2) as an
alternative to four times the tipping moment: (1) or 4,000 pounds,
whichever is greater; (2) or 150 % of the maximum pulling power of the
hoist, whichever is greater; or 4 times the rated load of the hoist,
whichever is greater. The SIA (Ex. 2-368) recommended changing the
resisting moment of proposed Sec. 1926.451(a)(2) to ``at least 1.5
times the stall capacity of the hoist or four times the maximum
intended load, whichever is greater.''
Three commenters (Exs. 2-8, 2-28, and 2-516) indicated that
Underwriters Laboratories (U.L.) standard 1323 (Standard for Scaffold
Hoists) limits the maximum output of a scaffold hoist to 3 times the
rated working load of the hoist. One commenter (Ex. 2-64) recommended
that OSHA limit the stall load of a hoist to no more than three times
the rated load of the hoist. Another commenter (Ex. 2-8) stated that if
the safety factor for suspended scaffolds is not based upon the highest
rated working load of any component, normally the hoist, failure can
occur.
Two commenters (Exs. 2-8 and 2-516) presented examples of the
relationship between the stall load of a hoist and the rated load of
the same hoist. One commenter (Ex. 2-8) provided the following example:
A typical hoist with a ``rated working load'' of 1000 lbs. can
exert a pulling force of 3000 lbs. if an obstruction is encountered
such as a window ledge or air conditioner while ascending. If one
designs for a maximum intended load of only 500 lbs. because of a
short light scaffold platform or a work cage and the counterweight
or suspension system is designed for 4:1 MIL then the ultimate load
that the suspension can support is 4 x 500 lbs. MIL or 2000 lbs. A
3000 lb. hoist pull can cause failure or even wire rope failure if 6
x MIL is used. No one intends to stall a hoist on an obstruction
but it does occur. Therefore, a suspended scaffold should be
designed for safety factors based upon MIL or rated working load of
the hoist whichever is greater.
OSHA agrees that the safety factors for the counterweights,
riggings, direct connections to roofs and floors, and suspension ropes
of adjustable suspension scaffolds should be related to the rated load
of the hoist and the stall load of the hoist, and not be based on the
maximum intended load. OSHA agrees with the commenters who stated that
failure can result if the factors of safety are based on the maximum
intended load. Furthermore, the Agency also agrees with the commenters
(Exs. 2-28 and 2-368) who indicated that these factors of safety should
be based on 1.5 times the stall load of the hoist.
The Agency notes that the stall load of a hoist is equal to three
times the rated load of that hoist. When one applies the 4 to 1 safety
factor required (4 x rated load = 4/3 x stall load) the result
would be 1.33 times the stall load. However, while using 1.33 times the
stall load would provide the required safety factor, OSHA is using 1.5
times the stall load based on the above comments. The Agency believes
that such a requirement reduces the possibility of failure due to
improperly installed equipment as well as the dynamic loads that can be
developed when an obstruction is encountered. Accordingly, the Agency
has changed the final rule language so that it requires a factor of
safety of four times the maximum rated load of the hoist or 1.5 times
the stall load of the hoist, whichever is greater.
Paragraph (a)(3) of the final rule provides that ``[e]ach
suspension rope, including its connecting hardware, used on non-
adjustable suspension scaffolds shall be capable of supporting, without
failure, at least 6 times the maximum intended load applied or
transmitted to that rope.'' This is the same requirement as the
proposed rule except that final rule paragraph (a)(3) applies only to
non-adjustable suspension scaffolds, while the requirements for
adjustable suspension scaffolds have been placed in final rule
paragraph (a)(4), below. The proposed rule did not distinguish between
these two types of scaffolds. Proposed paragraph (a)(4)(i) has been
redesignated to Sec. 1926.451(f)(11) of the final rule, to consolidate
all requirements for wire rope used with suspension scaffolds. In
addition, proposed paragraphs (a)(4)(ii) and (iii) have been moved to
non-mandatory Appendix A, so that examples of measures that would
comply with final paragraph (a) are consolidated in one place.
Paragraph (a)(4) of the final rule provides that ``[e]ach
suspension rope, including connecting hardware, used on adjustable
suspension scaffolds shall be capable of supporting, without failure,
at least 6 times the maximum intended load applied or transmitted to
that rope with the scaffold operating at either (a) The rated load of
the hoist, or (b) 2 (minimum) times the stall load of the hoist,
whichever is greater''.
This provision addresses adjustable suspended scaffolds and is
similar to proposed paragraph (a)(3) except that the proposed paragraph
contained the language ``maximum intended load applied or transmitted
to the rope'' instead of ``rated load of the hoist (or at least 2 times
the stall load of the hoist, whichever is greater)''. The proposed rule
was based on existing Sec. 1926.451(a)(19).
Three commenters (Exs. 2-8, 2-64, and 2-516) recommended that OSHA
use ``rated capacity of the hoist'' instead of ``maximum intended
load.'' This recommendation was based on the belief that the safety
factor for adjustable suspended scaffolds should be based on the
highest rated work load of any component, normally the hoist. The
Agency agrees and has modified the proposed rule accordingly. In
addition, the Agency has included language that accounts for the stall
load of the hoist in the factor of safety for the same reasons that
were discussed in regard to final rule Sec. 1926.451(a)(2), except that
the factor to be applied to the stall load has been increased from 1.5
to 2 in order to account for the 6:1 factor of safety applied to
suspension ropes. This factor of safety does not include an added
margin as does the factor of safety in paragraph (a)(2). One commenter
(Ex. 2-516) recommended an 8:1 factor of safety for suspension ropes on
adjustable suspension scaffolds. This recommendation was based on
several factors that can reduce the effective
[[Page 46035]]
strength of a rope: (1) A termination rating of 80% of the wire rope
design strength; (2) time-use of the rope; (3) energy applied to the
system when the overspeed brake is actuated; and (4) failure of the
brake to set or the loss of one end of the platform rigging. The
commenter concluded that these factors can reduce the factor of safety
from 6:1 to 1.15:1, with failure occurring if anything else goes wrong
such as the free end of the platform swinging through its arc.
OSHA notes that this commenter addresses a worst case scenario
which would involve violations of other provisions of the final rule.
The Agency believes that each of the elements of the scenario will be
prevented by compliance with the final rule. For example, final rule
Sec. 1926.451(d)(6) requires winding drum hoists to contain not less
than four wraps of the suspension rope at the lowest point of scaffold
travel, thereby reducing the force applied to the termination at the
winding drum. In addition, final rule Sec. 1926.451(d)(12)(v) prohibits
the use of U-bolt clips at the point of suspension for any scaffold
hoist. Also, final rule Sec. 1926.451(a)(3) requires that suspension
rope connections be considered part of the rope and that they be taken
into account when determining whether a rope is capable of withstanding
without failure at least six times the loads imposed upon it.
Further, final rule Sec. 1926.451(d)(10) requires that a competent
person inspect suspension ropes prior to each workshift or after any
occurrence which could affect a rope's structural integrity. Paragraph
1926.451(d)(10) also requires that defective or damaged ropes be
removed from service. For these reasons, OSHA believes that the final
rule adequately addresses the commenter's concerns.
The third commenter (Ex. 2-29) recommended that OSHA include the
weight of the scaffold and all its components in calculating maximum
intended load. The Agency believes the above described changes made to
proposed paragraph (a) resolve the concerns raised by this comment.
Paragraph (a)(5) of the final rule, which was not part of the
proposed rule, requires that the stall load of any scaffold hoist not
exceed 3 times its rated load. OSHA finds that this requirement is
reasonably necessary to prevent accidental overloading of suspension
scaffold support systems. OSHA notes that U.L. standard 1323 limits the
output force of a scaffold hoist to three times the rated load of the
hoist. As far as OSHA has been able to determine, the other
laboratories which test and list scaffold hoists adhere to the
requirements of U.L. 1323.
A commenter (Ex. 2-64) recommended that OSHA limit the stall load
of scaffold hoists to three times the rated load of the hoist. The
Agency agrees that it is appropriate to add the suggested provision,
for the reasons described above.
Final rule paragraph (a)(6) requires that scaffolds be designed by
a qualified person and constructed and loaded in accordance with that
design. The provision also indicates that non-mandatory Appendix A
provides examples of criteria, including design specifications, that
will enable the employer to comply with paragraph (a) of this section.
Proposed paragraph (a)(1), which focused on supported scaffolds, also
referenced Appendix A for acceptable criteria.
Non-mandatory Appendix A provides examples of design and
construction measures that employers can use to comply with final rule
Sec. 1926.451(a). This Appendix is based on the requirements set by
existing Secs. 1926.451(c)(1)-(4) and by Tables L-3 through L-19. OSHA
has recognized that employers can design and construct scaffolds which
satisfy the performance requirements of the final rule without
following the specifications set by the existing rule, and drafted both
the proposed and final rule Sec. 1926.451(a) accordingly. The Agency
believes that the above-cited specifications could assist an employer
in complying with the capacity requirements of the final rule, so OSHA
has relocated that language to non-mandatory Appendix A.
In Issue 5 of the preamble to the NPRM, OSHA requested comment on
whether or not all scaffold units (such as planks and decks) should
have their capabilities or grades marked on them. Some commenters (Exs.
2-41, 2-46, 2-51, 2-54, 2-73, 2-367, 2-495, 2-512, 2-516, and 2-534)
indicated they favored the requirements for such markings. Two
commenters (Exs. 2-495 and 2-534) stated ``very few people would know
which grade for any species of wood qualifies that plank as scaffold
grade.'' Those commenters recognized that there was a lack of consensus
concerning the maximum safe loads on certain plank spans, stating that
``[a]t the same time, we believe it may be premature to require that
all planks be so marked since agreement on methodology of determining
load displacement has not been reached by the engineering profession.''
Another commenter (Ex. 2-54) indicated that marks would not wear
off platform units because ``[i]n most instances, planks are placed and
not moved [and are] generally not rubbed against each other
constantly.'' Another commenter (Ex. 2-516) stated ``[i]f it is so worn
that the mark is lost, it probably needs retesting anyway.''
One commenter (Ex. 2-51) stated that while grade marks would wear
off, it seems unlikely ``that every plank on an entire job would
simultaneously suffer such a fate. We believe that invariably, there
would be some plank where grade stamping was legible if grade stamping
ever existed.''
Another commenter (Ex. 2-41) stated ``[k]nowledge of the capacity
of each [piece of] equipment is basic to implementation of this
proposal.''
In addition, the SSFI (Ex. 2-367) pointed out that fabricated plank
stages and platforms are currently marked as to their capacity. They
stated that this ``practice should be continued for fabricated planks,
stages, and platforms, as these are designed for unique applications.''
The commenter also stated ``there is no common practice within the
industry to have solid sawn lumber marked as to their load capacity.''
The SSFI recommended ``that the solid sawn lumber or laminated veneer
be repeatedly and continuously grade[-]stamped along the side edge of
the material at the time the plank is initially purchased.''
Another commenter (Ex. 2-51) stated that ``[s]ince 1980, Timber
Products Inspection has been involved in five cases where plank failure
has resulted in injury and litigation. In all five cases the planks
that failed were purchased as rough Canadian Spruce #1 and better or #2
and better. None of the planks were grade-stamped and one plank was
identified as Lodge pole pine instead of spruce.''
Another commenter (Ex. 2-35) recommended that OSHA adopt the
language of the ANSI A10.8 draft scaffold standard that requires
``solid sawn scaffold plank to bear the grade stamp of a grading agency
approved by the American Lumber Standards Committee.'' The commenter
also stated ``it is essential to assure use of scaffold members of
adequate strength and stiffness.''
In addition, a commenter (Ex. 2-534) stated:
We are strong advocates of requiring that all plank to be used
as scaffold plank be required to be stamped or embossed as
``SCAFFOLD PLANK''. To most people, all planks look alike. Very few
people would know which grade for any species of wood qualifies that
plank as scaffold grade unless the grade stamp is explicit for
flatwise use as ``Scaffold Plank''.
* * * There is everything to gain, and nothing to lose, by
requiring marks that
[[Page 46036]]
communicate to answer the bottom line question, ``Is this plank OK
as a scaffold plank?''
In addressing Issue 5, the ACCSH recommended (Tr. 6/9/87, pp. 64-
65) that all planking and decks, etc., be properly marked as scaffold
materials. The Advisory Committee indicated that a performance
standard, which would allow employers to determine how they wanted to
mark these materials, would be appropriate. Among the options
envisioned by the ACCSH to distinguish the materials intended solely
for scaffold system use were color-coding systems, stamping, and
tagging.
On the other hand, some commenters expressed the view that a
marking requirement would be impractical (Exs. 2-15, 2-20, 2-22, 2-368,
and 2-390). In addition, commenters (Exs. 2-20, 2-53, 2-55, and 2-390)
stated that the requisite costs would be burdensome, and others (Exs.
2-13, 2-15, 2-69, and 2-368) stated that, while manufactured or
fabricated planks or platforms were often or usually marked, carrying
this over to wooden components was inadvisable, citing anticipated
problems with the volume of planks to be marked and the marks wearing
off. Several commenters (Exs. 2-20, 2-55, 2-70, and 2-390) pointed out
the marks would lend a possibly false sense of security or safety, and
some (Exs. 2-20, 2-55, 2-69, and 2-390) added that maintaining the
marks would be neither feasible nor economical. One commenter (Ex. 2-
70) stated ``The user of platform units can calculate the maximum load
that can be placed on a scaffold and it is up to management personnel
to ensure that the scaffolding is not overloaded. I feel that the
marking of platform units does not, in itself, insure a safe
scaffolding.''
After careful evaluation of the above comments, the Agency has
decided not to require marking of platform units. OSHA has determined
that, while markings can increase confidence in and use of appropriate
platform units, they do not add to the inherent safety of the scaffold.
Furthermore, the absence of markings does not establish a lack of
quality.
In addition, materials quality is only one of several factors which
must be considered when erecting a scaffold platform. Other significant
elements include unit size, span, and load applied. A platform unit,
whether wood or metal, solid sawn or prefabricated, which is marked as
appropriate for use as a plank, may be appropriate for use in one set
of conditions but not in another (i.e., longer span or higher load).
Similarly, a platform unit which does not have the quality
characteristics to allow its use in one situation may be acceptable for
use in another (i.e., shorter span or lighter load) whether or not it
is marked. The important consideration in all situations is that the
platform be capable of supporting the load with a design factor of
four.
OSHA believes the grading rules of recognized independent
inspection agencies, such as the American Lumber Standards Committee
(ALSC), provide useful information about wood plank selection and use.
Planks that are marked and used in accordance with pertinent grading
rules of the ALSC or other recognized independent inspection agency
will be deemed to meet the four-to-one requirement. Therefore, given
the extent to which the private sector has voluntarily adopted plank
grading and marking programs, the Agency has concluded that any benefit
resulting from the addition of marking requirements would be minimal.
Wood products such as Canadian spruce, which are alleged to be
unacceptably inferior in some applications, could have standards
developed for their use by a recognized grading agency. OSHA believes
there are combinations of thickness, quality, span, loads, and other
factors that can be established for all species of wood used for
platforms.
Issue 17 of the preamble to the NPRM asked whether the Agency
should specify a minimum slippage capacity of 4,000 pounds and a
minimum breakage capacity of 16,000 pounds for couplers used on tube
and coupler type scaffolds. The SSFI and SIA (Exs. 2-367 and 2-368)
opposed such a requirement, stating that ``the entire scaffold
structure should be required to withstand the specified design loads.''
They also noted that this special component requirement was unlike
other OSHA requirements. The SIA (Ex. 2-368) also stated:
It is redundant and unnecessary to specify a quantitative value
for clamp strength since the required safety factors already in
existence provide the proper strength for the intended load. There
may be cases where the clamps should be of higher value or lower
value, depending on usage. Consequently, requiring a numerical value
may produce the catastrophe which the proposed rule is trying to
avoid in the first place. Existing rules require design by competent
individuals, which provides the proper safeguards against abuse and
eliminates the need for the proposed rule.
Also, a commenter (Ex. 2-15) indicated that a British standard (BS
1129) recognizing 2800 lb. has been in place for 20 years ``with
satisfactory results.'' The commenter stated that most American clamps
are built to BS1129, and went on to indicate that the same 2800 lb.
figure is generally sufficient, except for possible heavy-duty
applications in a specific configuration. The commenter further felt
that specifying a 4,000 lb. minimum slippage capacity would ``outlaw''
many clamps.
One commenter (Ex. 2-22) stated that both slippage and minimum
breakage capacities ``should be equivalent to that required on the
other parts of the scaffold.''
Another commenter (Ex. 2-128) stated ``couplers for tube and clamp
[scaffolds] should be rated by the manufacturer in accordance with a
recognized testing standard [and] certified by an engineer.'' In
addition, a commenter (Ex. 2-13) expounded on the relationship between
the torque applied to tighten a coupler and the slippage capacity, and
noted that proper torque values needed to be determined by tests or
calculations.
The ACCSH (Tr. 6/9/87, pp. 138-147) recommended that OSHA specify
both minimum slippage and breakage capacities and should require
employers to obtain manufacturer's specifications and/or certifications
that a scaffold meets minimum standards. However, the ACCSH did not
endorse the suggested 4000 and 16,000 pound limits and did not propose
any other limits.
After a careful review of the above comments, OSHA has determined
that the capacity provisions set out in final rule Sec. 1926.451(a)
will appropriately address the concerns regarding scaffold strength and
that additional specifications would be redundant.
Issue 21 of the preamble to the NPRM requested public comment on
appropriate field test procedures or certifications for determining the
capacity of scaffolds and scaffold components such as planks and ropes.
As noted above, existing Sec. 1926.451(a)(7) and proposed
Sec. 1926.451(a)(1) require scaffolds to be capable of supporting,
without failure, at least four times the maximum intended load. OSHA
has recognized, however, that field testing of scaffolds and scaffold
components with loads four times greater than the maximum intended load
could cause damage that would render the scaffold and scaffold
components unusable.
One commenter (Ex. 2-54) mentioned reliance on testing laboratories
to ensure that rope and planks meet industry standards. Another
commenter (Ex. 2-64) stated that scaffolds' and support systems' rated
capacities should be marked when manufactured and that any field
testing beyond that set forth in a manufacturer's instructions would be
superfluous and could conflict with those instructions.
[[Page 46037]]
The SSFI (Ex. 2-367) and the SIA (Ex. 2-368) both stated that field
testing of supported scaffolds would permanently damage equipment or
render it useless, and that a visual check of the scaffolding before
use should ensure safety ``as the manufacturer already warrants the
appropriate safety factors.'' The SIA also stated that current testing
methods ``are not suitable for checking the ultimate capacity of
scaffold components.'' The SIA further stated that for metal
components, visual inspection is the only practical method available.
For wooden components, the SIA stated that inherent material variables
make obtaining repeatable results from a suitable bending test
impossible. On the other hand, the SIA recommended that suspension
scaffolds be field tested with the intended load.
Two other commenters (Ex. 2-495 and 2-534) agreed with the SIA that
it is impossible to obtain repeatable results from a bending test.
However, they stated that a minimum threshold design value for flat-
wise bending of planks could be derived from available information for
flat-wise bending for any specie of plank. Those commenters also stated
that field testing would not necessarily permanently damage or render a
plank useless. They stated that strength testing of used planks could
be accomplished by combining visual inspections with deflection testing
using a safe load and deflection testing machines that are currently
available.
One commenter (Ex. 2-516) indicated that a reasonable level of load
testing for scaffold machinery might be found ``somewhere near 1.25
times [the] rated load'' and that ``any field tests should be a ratio
of rated load, not failure load.'' The commenter assumed different
safety factors for moving equipment, suspended scaffold hoists, and
fixed structures. The commenter also questioned whether the safety
factor referred to in Issue 21 was for static, dynamic, or shock loads,
and noted that 4 to 1 is not an engineering safety factor but a gross
factor. In addition, the commenter stated:
Any device or mechanism designed for a structural safety factor
of four-to-one certainly can be tested at some level less than four-
to-one without structural failure. * * * It is difficult to
comprehend the rationale of prohibiting testing of a structure using
1\1/2\ times rated load for fear it will collapse, when the
structure must not collapse at 4 times rated load. There would then
be doubt in my mind as to its ability to meet that 4-to-1 criterion.
Also, the commenter (Ex. 2-516) pointed out that any test of wood
components should consider the effects of aging material, and he listed
a number of variables for which some testing adjustments would be
required. These variables included ``fatigue, finish,'' and ``material
test scales.''
Two commenters (Exs. 2-13 and 2-69) indicated there would be no
need for field testing since scaffolds should be designed for their
intended load with an added safety factor. In particular, one of those
commenters (Ex. 2-13) stated ``[t]here are no appropriate field tests
for such items as planks and ropes. A simple visual inspection is all
that is required by a competent person.''
The ACCSH (Tr. pp. 163-174, 6-9-87) recommended that the
manufacturer's design specifications be recognized as sufficient for
manufactured scaffolds. The ACCSH also recommended that specifications
or testing procedures be specified for job-made scaffolds.
After carefully considering the above comments, OSHA has decided
not to require field testing of scaffolds. Based on the comments
received, the Agency has determined that such testing is not needed and
that, given the inspection and capacity requirements, it would be
difficult or impossible to implement effectively for the range of
materials in question.
Issue 23 of the preamble to the NPRM solicited comments on whether
or not the Agency should revise paragraph 1.(b) of proposed non-
mandatory Appendix A, which provides for selection of wood scaffold
planks according to the grading rules established by a recognized
independent inspection agency. In particular, OSHA asked if the
language should be more specific and, if so, what that language should
be.
Four commenters (Exs. 2-13, 2-22, 2-29, and 2-53) responded that
the proposed Appendix A language was adequate. One commenter (Ex. 2-13)
added ``it should be mandatory that the employer visually check all
scaffold planks before they are used.'' Another commenter (Ex. 2-54)
stated that scaffold planks ``should have identification'' to indicate
that they are scaffold grade.
However, a commenter (Ex. 2-534) noted that ``it may be premature
to require that all planks be so marked since agreement on methodology
of determining load displacement has not been reached by the
engineering profession.''
The SSFI (Ex. 2-367) recommended that scaffold planks be marked,
and noted that the most plank failures are inspection related. The SIA
(Ex. 2-368) recommended that OSHA revise paragraph (b) of proposed
Appendix A to read, in part, as follows:
All solid sawn planking shall be `SCAFFOLD GRADE' plank and
grade stamped as appropriate per the published grading rules of the
recognized independent inspection agency and as approved by the
Board of Review of the American Lumber Standards Committee. The
maximum permissible spans for 2 x 10 inch (nominal 1\1/2\'' x
9\1/4\'' minimum dressed (S4S), 1\5/8\'' x 9\1/2\'' minimum rough
or 2'' x 10'' minimum rough, solid sawn wood planks shall be as
shown in the following table.
Paragraph 1(b) of Appendix A should be expanded and clarified to
eliminate the confusion that exists over the use of nominal
thickness scaffold grade planks on 10 ft. spans for light trades.
This could be achieved by defining a scaffold grade plank in the
manner done in Cal-OSHA standards.
Cal-OSHA Section 1637(e) requires what it calls a ``structural
plank'' for scaffold platforms as follows:
``Except as specified in certain other Orders, all planking
shall be 2-inch (nominal) material selected for scaffold grade plank
as defined in Section 1504 under the heading Lumber--`Structural
Plank'.''
The ACCSH, in its June 9, 1987 (Tr. pp. 175-180), meeting,
recommended that a competent person be responsible for the selection
and use of scaffold materials, where scaffolding materials are not
certified by the manufacturer.
After carefully considering the above comments, OSHA has decided to
modify paragraph 1.(b) of non-mandatory Appendix A to the final rule to
provide for identification of scaffold planks by the grade stamp of the
recognized lumber grading association or independent lumber grading
inspection agency under whose grading rules the planks were selected.
OSHA is also modifying proposed Appendix A to provide that the
association or agency under which the wood is graded should be
certified by the Board of Review, American Lumber Standard Committee as
set forth in the American Softwood Lumber Standard of the U.S.
Department of Commerce. This added language clearly indicates what
constitutes a ``recognized'' inspection agency.
As a separate matter, OSHA is modifying Appendix A to the final
rule to provide that allowable spans of scaffold planks, other than 2 x
10 inch (nominal) or 2 x 9 inch (rough) solid sawn planks which are
addressed in the table in paragraph 1 (b), shall be determined in
accordance with the National Design Specification For Wood Construction
published by the National Forest Products Association or with ANSI
A10.8-1988, paragraph 5. OSHA notes that Appendix A is intended to help
the employer comply with the scaffolding rules. The Agency believes
that the above modifications will facilitate compliance with those
rules.
[[Page 46038]]
Paragraph (a)(6) of the final rule, which was not part of the
proposed rule, requires that scaffolds be designed by a qualified
person and must be constructed and loaded in accordance with that
design. OSHA believes that a ``qualified'' person can design a scaffold
which satisfies the criteria of Sec. 1926.451(a). This provision also
notes that non-mandatory Appendix A contains examples of criteria that
will enable employers to comply with paragraph (a) of this section.
Issue 24 of the preamble of the NPRM noted that existing
Secs. 1926.451(b)(16), (c)(4), (c)(5), (d)(9) and (g)(3) and proposed
Sec. 1926.451(b)(18)(i) and Secs. 1926.452(a)(10), (b)(10), (c)(6) and
(i)(8) require that an engineer design specified scaffold types and/or
components that are not built or loaded in accordance with Tables L-4
through L-13 of existing Sec. 1926.451 or proposed Sec. 1926.451
Appendix A, respectively. OSHA asked for comments regarding the extent
to which the services of an engineer or of a qualified person would be
needed to design scaffolds in accordance with the provisions of
Appendix A or to design scaffolds that, while not in accordance with
Appendix A, would comply with Sec. 1926.451(a).
Two commenters (Exs. 2-69 and 2-437) responded that employers
should be allowed to assess whether individual employees with several
years of hands-on experience are capable of designing and modifying
scaffolds or an engineer's services are required. Also, a commenter
(Ex. 2-22) expressed the view that there was no need for further
licensing and determinations because employers are responsible for
ensuring that scaffolds meet regulations for capacity and that
alterations of scaffold designs are made by qualified individuals. The
AGC commenters (Exs. 2-20, 2-55, and 2-390) stated ``there are many
individuals in the construction industry with many years of experience
who are quite capable of scaffold design and modification. Employers
should be permitted the flexibility to determine if such individuals
are capable or if they should seek the services of an engineer.''
Another commenter (Ex. 2-54) noted that not all engineers are
capable of designing scaffolds and that a good many people who work
with scaffolds do not know all the scaffold limits or strengths. The
commenter acknowledged that complicated scaffold designs require the
skills of an engineer familiar with the equipment available. However,
the commenter added that a competent worker who has followed an
engineer's drawings to erect a scaffold can at times recall and use
that experience in another situation requiring a complicated scaffold
structure.
In addition, a commenter (Ex. 2-21) stated that no additional
specification requiring the use of engineering services was warranted.
The commenter explained that ``[c]onditions on most construction jobs
change daily and can best be handled by qualified foremen or
supervisors on the job.'' Also, a commenter (Ex. 2-31), addressing
pumpjack scaffolds specifically, responded that although he was not an
engineer himself, he knew at least as much as anyone else about
pumpjack scaffolds. He felt that an engineer could be supplanted by
someone with recognized expertise but added that he did not believe a
specific definition of someone qualified to design a scaffold system
could be made.
Both the SSFI (Ex. 2-367) and the SIA (Ex. 2-368) recommended that
a ``qualified person,'' as defined in proposed ANSI A10.8, be allowed
to design those scaffolds that would not require the services of a
registered engineer. They quoted the proposed ANSI definition as
follows:
A term describing one who, by possession of a recognized degree,
certificate, or professional standing, or who by extensive
knowledge, training, and experience, has successfully demonstrated
the ability to solve or resolve problems relating to the subject
matter, the work, or the project.
The suggested definition is identical to the definition of
``qualified'' in Sec. 1926.32(l).
Two Saf-t-Green commenters (Exs. 2-14 and 2-15) stated that people
other than engineers were capable of designing scaffolds. In
particular, one commenter (Ex. 2-15) stated ``There are many good,
practical scaffold designers who are not engineers. They should not be
excluded.''
On the other hand, some responses to Issue 24 stated that the
services of a registered or professional engineer were needed (Exs. 2-
3, 2-9, 2-13, 2-70, 2-128, and 2-516). One such commenter (Ex. 2-13)
stated that he backed using registered professional engineers ``with
the knowledge and training required for [designing] a life support
system'' and queried where ``an equivalent qualified responsible person
could be found?'' One commenter (Ex. 2-70) offered a brief response,
``when in doubt, consult an engineer.'' Another commenter (Ex. 2-516)
responded:
I would rather take my chances with the engineer [-designed
scaffold system]. At least he knows some limits. Any other
definition lets anyone determine by themselves that they are
eminently qualified. All it then takes to be qualified is a big ego,
a little knowledge, and a pile of frame scaffold.
A comment from Aluma-Systems, Incorporated (Ex. 2-128) expressed
the belief that an engineer's services should be required for all but
the simplest of scaffold structures. The commenter indicated that the
Province of Ontario requires that a professional engineer design any
scaffold which exceeds 15 meters in height (approximately 50 feet), any
suspension scaffold where the scaffold consists of more than one
platform, or any suspension scaffold where the weight of the platform
and its components exceed 363 kg.
In addition, two commenters (Exs. 2-12 and 2-53) responded that the
existing regulations were sufficient or adequate. One of the two (Ex.
2-12) stated that there was already sufficient regulation and
questioned whether rules could be made to cover all situations.
In its June 9, 1987, meeting, the ACCSH (Tr. pp. 180-183)
recommended that OSHA authorize a competent person, rather than a
qualified person, to follow Appendix A for scaffold design, but that a
registered professional engineer be required to design scaffolds where
conditions are not covered by Appendix A. The Agency notes that a
competent person, as defined in Sec. 1926.32(f) and in the final rule
for subpart L, is able to detect hazards and has the authority to have
hazards corrected. On the other hand, ``qualified'', as defined in
Sec. 1926.32(m) and in the final rule for subpart L, refers to a person
who has the ability to solve or resolve safety and health problems.
After carefully considering the above comments, OSHA believes that
the proposed rule adequately addressed the conditions under which a
scaffold must be designed by an engineer. Accordingly, the above-listed
proposed requirements (Sec. 1926.451(b)(18)(i) [now final rule
Sec. 1926.451(d)(3)(i)] and Secs. 1926.452(a)(10), (b)(10), (c)(6), and
(i)(8)) have been promulgated in the final rule. As discussed below,
proposed rules Sec. 1926.452(a)(10) and (b)(10) have been revised to
distinguish more clearly between those circumstances where the employer
would need the services of a registered professional engineer and those
situations where the services of a qualified person, who could refer to
non-mandatory Appendix A, would be sufficient.
The Agency believes that there are qualified persons who can
properly design scaffolds without reference to Appendix A. The Agency
also believes that there will be circumstances where the ``qualified
person'' retained to comply with paragraph (a)(6) will need to be a
registered professional engineer.
[[Page 46039]]
Paragraph 1926.451(b) Scaffold Platform Construction
Paragraph 1926.451(b) of this final rule provides criteria for the
construction of scaffolds. Paragraph (b)(1) requires all platforms,
except walkways and those platforms used by employees performing
scaffold erection and dismantling operations, to be fully decked or
planked. In addition, paragraph (b)(1)(i) requires that platform units
be placed so that spaces between units do not exceed 1-inch, except
where employers establish that more space is needed. For example, this
would be necessary to fit around uprights when using side brackets to
extend platform width. Paragraph (b)(1)(ii) provides that, where the
exception created by paragraph (b)(1)(i) applies, employers shall place
platform units as close together as possible, with the space between
the platform and uprights not to exceed 9\1/2\ inches. OSHA set 9\1/2\
inches as the maximum space allowed, because the minimum width for
scaffold units that could be expected to sustain a working load is just
over 9\1/2\ inches. This provision, which is effectively identical to
the provision in the proposed rule, codifies the Agency's longstanding
interpretation of existing Sec. 1926.451(a)(4), which addresses
guardrails on scaffolds, to require that guardrails be erected as close
as possible to the platform planking. Because guardrails normally can
be conveniently attached only at the scaffold uprights, OSHA has
required the platforms to be sized such that there is no gap between
the outermost plank edge and the guardrail. However, most prefabricated
end frames do not have a lateral spacing between uprights which can
accommodate an integral number of commercially-available planks. In
order to comply with the existing rule, some employers have modified
the last plank (notched, slanted, or cut it to size). This can lead to
a significant reduction in plank strength, and possibly cause tipping
of the plank (sideways) if eccentrically loaded. Therefore, to deal
with this problem, proposed and final rule paragraph (b)(1) have
modified the corresponding requirement of the existing standard by
requiring the span between uprights to be planked or decked as fully as
possible, but allowing up to 9\1/2\ inches between the planking or
decking and the guardrail supports. As explained above, 9\1/2\ inches
is the maximum allowable open space.
One commenter (Ex. 2-29) stated that the 1-inch opening allowed by
proposed paragraph (b)(1)(i) would be large enough to ``allow many
tools and small materials to fall through'', and recommended a maximum
space of \1/4\ inch between units. OSHA, however, finds that such a
small maximum space would pose unreasonable compliance burdens, and is
retaining the 1-inch maximum.
The SSFI and the SIA (Exs. 2-367 and 2-368) stated that compliance
with proposed paragraph (b)(1) would be impossible when erecting or
dismantling scaffolds. In particular, the SIA (Ex. 2-368) stated:
For example: On a multi-level supported scaffold where
construction work is to be performed only at the top level, lower
levels would not be planked. Erectors would only use sufficient
planks required to construct the scaffold.
Load requirements limit the number of levels that can be planked
on many installations. The additional cost in labor and material
would be staggering. In addition, the fatigue factor created by
installing full planking from one level to the next would create a
greater hazard to the erectors.
The Agency agrees with the SIA comments and acknowledges that a
requirement to fully plank under these conditions would unreasonably
interfere with the erection and dismantling process. The Agency also
agrees that a requirement to fully plank every intermediate platform
level, where no work other than scaffold erection or dismantling
operations will occur, is overly burdensome. Therefore, OSHA has
revised proposed paragraph (b)(1), which already excepted walkways from
the requirement for full planking or decking, to add an exception to
the final rule to the planking requirements for erection or dismantling
operations. In a situation where no work, other than erecting or
dismantling the scaffold, is being done at intermediate levels, the
final rule requires only that the planking established by the employer
as necessary to provide safe working conditions for employees erecting
or dismantling the scaffold be used. On the other hand, if scaffold
erection or dismantling is being performed from an intermediate level
platform that is being or will be used as a work area, that platform
must be fully planked in accordance with paragraph (b)(1).
Paragraph (b)(2) of the final rule requires that all scaffold
platforms and walkways be at least 18 inches (46 cm) wide, with lesser
widths allowed for ladder jack scaffolds, top plate bracket scaffolds,
pump jack scaffolds, roof bracket scaffolds, and boatswains' chairs,
and for scaffolds in areas shown to be too narrow to accommodate an 18-
inch wide surface. Proposed paragraph (b)(2) also required a minimum
18-inch width, with exceptions for ladder jack scaffolds (12 inches)
and boatswains' chairs (any width). The rationale for setting a 12-inch
minimum width for ladder jack scaffolds, as discussed in the preamble
of the proposal (51 FR 42684-85), was the difficulty of handling one
18-inch wide plank or two 9-inch planks on a ladder, which the Agency
considered more hazardous than working on a 12-inch wide plank. In the
final rule, OSHA has also included pump jack scaffolds in the exception
to paragraph (b)(2) for which a minimum platform width of 12 inches is
permitted, based on a commenter's statement (Ex. 2-31) that OSHA's
performance criteria for pump jack scaffolds enable employees to work
safely on platforms that are 12 inches or 14 inches wide. The commenter
also indicated that requiring pump jack scaffold platforms to be at
least 18 inches, instead of 12 inches, wide would create ``an economic
hardship * * * for this very prevalent size aluminum platform.'' OSHA
agrees that pump jack scaffolds with platforms as narrow as 12 inches
can satisfy the performance criteria of the final rule and has revised
paragraph (b)(2) accordingly.
In addition, the Agency is recognizing top plate bracket scaffolds
and adding them to the list of scaffolds which are permitted to have
platforms not less than 12 inches in width. As discussed above in the
definition section, these are supported scaffolds, similar to
carpenters' bracket scaffolds and form scaffolds, which consist of a
platform supported by brackets that hook over or are attached to the
top plate of a wall. These scaffolds are used in residential
construction for setting trusses, usually for high ceiling situations
(e.g., cathedral ceilings, atria). The Agency has determined that use
of this type of scaffold, even with a 12-inch wide platform, provides
greater protection for employees setting trusses than the use of
ladders, makeshift scaffolds or walking the top plate. OSHA concludes
that it would be less safe to require wider platforms for top plate
scaffolds because setting up this type of scaffold would then require
handling and positioning an 18-inch wide platform or two nine-inch wide
platforms, and handling and positioning larger, heavier brackets, which
is usually done from ladders. OSHA finds that this would be more
hazardous than working on one 12-inch wide platform equipped with fall
protection.
As proposed, OSHA is deleting the requirement that appeared in the
existing scaffold rule at Sec. 1926.451(l)(1), which sets the minimum
dimensions of
[[Page 46040]]
a boatswains' chair at 12 inches by 24 inches, because, with the advent
of slings and molded seats, the Agency believes that setting minimum
dimensions is overly restrictive. This performance-oriented approach is
reflected by the inclusion of language in paragraph (b)(2)(i) which
specifically exempts boatswains' chairs from any width requirements.
The SIA (Ex. 2-368) suggested that platforms as narrow as 12 inches
wide be allowed in areas where entryways are restricted. Another
commenter (Ex. 2-64) suggested that suspension scaffolds designed for
special applications (e.g., to fit through manholes) be permitted to be
as narrow as 12 inches. OSHA realizes that there may be instances where
the nature of the work being performed makes it impossible to make
platforms and walkways at least 18 inches wide. Where the employer can
establish that such a situation exists, the Agency will accept
platforms and walkways that are less than 18 inches wide, provided both
that such platforms and walkways are as wide as is feasible and that
employees are adequately protected from fall hazards by the use of
guardrails and/or personal fall arrest systems, as required by
paragraph (g).
Final rule paragraph (b)(3) (proposed as paragraph (b)(4)) sets the
requirements for the space between the front edge of a platform and the
face of the structure where the scaffold is being used. Paragraph
(b)(3) requires that, except as provided in paragraphs (b)(3)(i) and
(b)(3)(ii), the front edge of all platforms must be no more than 14
inches from the face of the structure, unless the employer implements
guardrail systems or personal fall arrest systems that comply with
paragraph (g) of the final rule to protect employees from falling
between the platform and the structure. Final rule paragraph (b)(3)(i)
requires that the front edges of outrigger scaffolds be no more than
three inches from the face of the structure, as is required by
Sec. 1926.451(g)(4) of OSHA's existing standard. Final rule paragraph
(b)(3)(ii) requires that the front edges of scaffolds used for
plastering and lathing operations be no more than 18 inches from the
face of the structure.
The 18-inch dimension was developed from data collected by Wang
Associates (Ex. 5) which show that a shorter distance between the
scaffold platform and the wall is not feasible for the operators of
plastering and lathing equipment because of interference with the tools
used during such operations. However, these same operations cause the
employee to stand back from the edge and the hazard of falling is
correspondingly reduced. The SIA (Ex. 2-368) supported the 18-inch
provision as being necessary for the types of work covered, while
acknowledging that in some cases 14 inches would be adequate.
Final rule paragraph (b)(3) is effectively identical to proposed
paragraph (b)(4), except that the proposed provision specified ``Type
I'' guardrails instead of requiring compliance with paragraph (g). OSHA
has deleted the designations ``Type I'' and ``Type II'' from the final
rule for subpart L, as discussed above in relation to the definition of
``Guardrail system''.
Existing Sec. 1926.451(a)(4) requires guardrails on all open sides
and ends of a scaffold platform, but does not specify how far away a
scaffold platform may be from a building before the side facing the
building is considered to be an ``open side.'' OSHA's existing scaffold
rule has often been interpreted to mean that no open space is allowed.
However, zero clearance during all phases of construction is not
feasible. The 14-inch limit in proposed paragraph (b)(4) recognized
that during construction the face of the wall being built often moves
out toward the scaffolds. There must be sufficient space at the
beginning of work to allow for the installation of insulation, lathing,
plaster, masonry units, ledges, facings and other architectural or
structural additions. The spacing must be allowed for from the start,
because it is not practical to move large scaffolds away from the wall
as wall construction progresses outward. When the initial set back
distance must be more than 14 inches, the platform can often still be
kept within 14 inches of the building by the use of side brackets or
extensions on supported scaffolds, and by angulated roping, static
lines, or equivalent means on suspension scaffolds.
Two commenters (Exs. 2-41 and 2-465) questioned the use of 14
inches in this provision, suggesting that a maximum of 12 inches be
allowed. While OSHA recognizes that the suggested 12-inch spacing could
be marginally more protective, the Agency also recognizes that, as
discussed above, in many cases an unobstructed working space of at
least 14 inches is necessary. OSHA also notes that ANSI A10.8-1988,
paragraph 4.5.9, allows up to a 16-inch space for supported scaffolds
and a 12-inch space for suspended scaffolds. In support of OSHA's
position, the SIA (Ex. 2-368) endorsed the proposed language as the
proper solution to the problem, while noting that it would prefer 18
inches. The Agency believes that the 14-inch space appropriately
addresses both the safety concerns and the need to allow necessary room
for many of the jobs normally performed from scaffolds.
Final rule paragraph (b)(4) requires each end of a platform unit,
unless cleated or otherwise restrained by hooks or equivalent means, to
extend over the center line of its support at least six inches (15 cm).
This provision is virtually identical to proposed paragraph (b)(5),
which was based on existing Sec. 1926.451(a)(14). The use of cleats,
hooks, and similar securing devices would also be allowed as
alternatives to the six inch extension in the proposed and final rules,
because of their ability to restrain movement of platform units.
OSHA received one comment (Ex. 2-40) on this provision, which
stressed the importance of securing platform units against movement.
Final rule paragraph (b)(5) (proposed paragraph (b)(6)) addresses
the maximum distance platform units may extend over their supports. In
particular, paragraph (b)(5)(i) provides that each end of a platform
unit 10 feet (3 m) or less in length shall not extend over its support
more than 12 inches (30 cm) unless the unit is designed, and installed
so that the cantilevered portion of the unit is able to support
employees or material without tipping or has guardrails which prevent
employee access to the cantilevered end. In addition, paragraph
(b)(5)(ii) provides that each platform unit greater than 10 feet in
length shall not extend over its support more than 18 inches (46 cm),
unless the unit is designed and installed so that the cantilevered
portion of the unit is able to support employees without tipping, or
that the unit has guardrails which block employee access to the
cantilevered end.
OSHA proposed to change the maximum overhang allowed by existing
Sec. 1926.451(a)(14) from 12 inches to 18 inches because many planks in
use are 10 feet long, and are used to span eight foot distances. OSHA
also notes that ANSI A10.8-1988, paragraph 4.17, limits planks from
extending more than 18 inches over their supports, without regard to
the length of the plank.
OSHA's thinking at the time of the proposal was that the existing
requirement was unnecessarily restrictive, and that strict adherence to
the existing maximum overhang limit would require platform units to be
cut if they extended beyond the 12-inch limit.
Although no comments were received on this provision, OSHA has
concluded, upon further consideration of this matter, that the maximum
overhang allowed, unless the above specified
[[Page 46041]]
measures have been taken, should be limited to 12 inches for planks 10
feet or less in length, and 18 inches for planks greater than 10 feet
in length. The Agency concludes that allowing an 18-inch overhang as a
matter of course would be unsafe, because the weight of an employee on
an 18-inch overhang could easily tip a 10-foot plank. However, an 18-
inch overhang on a plank that is longer than 10 feet would be
permissible because the additional weight of the longer platform would
offset the weight of the employee on the overhang. In addition, an
employer who seeks to use platform units that overhang the supports
more than the prescribed distance would be required to satisfy the
performance criteria of paragraph (b)(5) of the final rule.
Under final rule paragraph (b)(6), where platform units are abutted
to create a long platform, each abutted end shall rest on a separate
support surface. Abutted platform units do not rest one on another, but
instead are end-to-end. Consequently, one unit does not support the
other, and proper support can only be provided by separate support
surfaces. This provision is virtually identical to proposed paragraph
(b)(7), except that the final rule has deleted the words ``butt plate
or equivalent means of support'', because those words add nothing to
the requirement for ``separate support.'' This provision is based on
existing Sec. 1926.451(b)(12), which currently applies only to wood
pole scaffolds. OSHA has determined that all scaffolds need proper
platform support and, accordingly, has promulgated this provision.
The Agency has also added a note to this provision stating that
common support members such as ``T'' sections or hook-on platforms
designed to rest on common supports are not prohibited by this
provision. The Agency is doing this to prevent confusion since these
commonly used support members might be considered not to meet the
requirements of this provision.
Final rule paragraph (b)(7) provides that where platforms are
overlapped to create a long platform, the overlap shall occur only over
supports, and shall not be less than 12 inches (30 cm) unless the
platforms are nailed together or otherwise restrained to prevent
movement. This provision is virtually identical to proposed paragraph
(b)(8) which was based on existing Sec. 1926.451(a)(12).
Final rule paragraph (b)(8) requires that at all points of a
scaffold where the platform changes direction, such as turning a
corner, any platform that rests on a bearer at an angle other than a
right angle shall be laid first and platforms which rest at right
angles over the same bearer shall be laid second, on top of the first
platform. This provision is virtually identical to proposed paragraph
(b)(9), which was based on existing Sec. 1926.451(b)(13). While this
provision in OSHA's existing standard addresses only wood pole
scaffolds, OSHA has determined, as with final rule paragraph (b)(6),
that the existing requirement is appropriately applied to the
construction of all scaffold platforms.
Final rule paragraph (b)(9) provides that wood platforms shall not
be covered with opaque finishes, except that platform edges may be
covered or marked for purposes of identification. Platforms may be
coated periodically with wood preservatives, fire-retardant finishes,
and slip-resistant finishes, but the coating may not obscure the top or
bottom wood surfaces. This paragraph is intended to ensure that
structural defects in platforms are not covered from view by the use of
an opaque coating or finish. Hairline cracks can significantly reduce
the strength of a wood member, so early detection of structural defects
is important. Opaque finishes can cover such cracks and make them
difficult to discover. The edges of platform units are excepted from
this rule to allow identification marks, grading marks, or other
similar type of marks to be placed on the unit edges.
This provision is virtually identical to proposed paragraph
(b)(10). The proposal addressed the use of wood preservatives, fire
retardant finishes and slip-resistant finishes in a ``note'', while the
final rule has incorporated the pertinent language directly into the
regulatory text. In short, those finishes may be used as long as they
do not obscure the top or bottom wood surfaces.
Final rule paragraph (b)(10) requires that scaffold components
manufactured by different manufacturers not be intermixed unless the
component parts fit together without force and the resulting scaffold's
structural integrity is maintained by the user. Scaffold components
manufactured by different manufacturers shall not be modified in order
to intermix them unless the resulting scaffold is determined by a
competent person to be structurally sound. OSHA expects that the
competent person who evaluates the scaffold will have the appropriate
knowledge, skill and experience regarding scaffold systems and
components.
This provision is identical to proposed paragraph (b)(11), except
that the proposal did not contain the phrase ``and the resulting
scaffold's structural integrity is maintained by the user''. The SIA
(Ex. 2-368) suggested the added language, citing the ``latest ANSI
A10.8 draft.'' The Agency acknowledges that a scaffold may lack the
requisite structural integrity even though the intermixed components
``fit together without force.'' OSHA agrees that the requirement to
maintain structural integrity should be clearly stated in this
provision and has revised the final rule accordingly.
One commenter (Ex. 2-29) stated ``[m]any, if not all, scaffold
manufacturers void any liability if their scaffold components are
intermixed * * * A standard requirement should not result in a lesser
degree of safety; neither should it encourage an employer to take a
course of action that could increase his liability.'' The SSFI (Ex. 2-
367) stated ``[i]t would be the Institute's recommendation that
scaffold components not be intermixed even though they may re[a]dily
fit together without force. Many times the capacity or bracing
alignment would not be the same as other types of scaffold, thus
creating a hazardous situation.'' OSHA agrees that an unsafe condition
could exist when parts are intermixed, unless adequate precautions are
taken, and believes that paragraph (b)(10), as modified, in conjunction
with Sec. 1926.451(a), provides for adequate precautions to be taken by
the employer to ensure against this eventuality.
Paragraph (b)(11) of the final rule provides that scaffold
components made of dissimilar metals shall not be used together unless
a competent person has determined that galvanic action will not reduce
the strength of any component to a level below that required by
Sec. 1926.451(a). This provision, while effectively identical to
proposed paragraph (b)(12), differs from Secs. 1926.451(c) (1), (2) and
(3) of OSHA's existing rule, which prohibit the use together of any
dissimilar metals on tube and coupler scaffolds. The proposed rule was
intended to extend the prohibition to all scaffolds, because the
problem of dissimilar metals causing galvanic action can occur on any
scaffold, not just tube and coupler scaffolds. However, the proposed
rule was not intended to prohibit all uses of dissimilar metals because
there are many combinations which do not produce significant galvanic
reactions.
One commenter (Ex. 2-41) expressed skepticism as to the ability of
a competent person to discern that galvanic action has not reduced the
strength of any component. However, OSHA finds that any competent
person, as defined by this subpart, would be able to identify the
causes and significance of any deterioration in
[[Page 46042]]
scaffold components. In particular, OSHA expects the competent person,
who is on site and required to inspect the scaffold, to recognize
deterioration due to galvanic reactions, and to take prompt corrective
action.
Paragraph 1926.451(c) Criteria for Supported Scaffolds
Final rule Sec. 1926.451(c) sets criteria for the use of supported
scaffolds. Paragraph (c)(1) of the final rule requires that supported
scaffolds with a height to base width ratio of more than four to one
(including outrigger supports, if used) be restrained from tipping by
guying, tying, bracing, or equivalent means. That provision is based on
existing Sec. 1926.451(e)(1), which covers manually-propelled mobile
scaffolds. Any type of supported scaffold can topple if its center-of-
gravity is too high, and OSHA has therefore expanded the coverage of
this paragraph in the final rule. Final rule paragraph (c)(1)(i)
provides that guys, ties, and braces shall be installed at locations
where horizontal members support both inner and outer legs. In
addition, paragraph (c)(1)(ii) requires, as follows:
(1) Guys, ties, and braces shall be installed according to the
scaffold manufacturer's recommendations or at the closest horizontal
member to the 4:1 height and be repeated vertically at locations of
horizontal members every 20 feet (6.1 m) or less thereafter for
scaffolds 3 feet (0.91 m) wide or less and every 26 feet (7.9 m) or
less thereafter for scaffolds greater than 3 feet (0.91 m) wide;
(2) The top tie, guy or brace of a completed scaffold shall be
placed no further than the 4:1 height from the top; and
(3) Such guys, ties and braces be installed at each end of the
scaffold and at horizontal intervals not to exceed 30 feet (9.1 m)
(measured from one end [not both] towards the other).
This provision of the final rule is essentially the same as
proposed paragraph (b)(13), except that the maximum vertical spacing
has been changed to allow for the scaffolds to be supported at their
strongest points. Proposed paragraphs (b)(13)(i) and (b)(13)(ii), which
specified the horizontal spacing for ties, guys, and braces, were
intended to replace existing Secs. 1926.451 (b)(4), (c)(12), and
(d)(7). These paragraphs of the existing rule required pole scaffolds,
tube and coupler scaffolds, and fabricated frame scaffolds to be tied
and braced at intervals no greater than 26 feet vertically (25 feet for
wood pole scaffolds) and 30 feet horizontally (25 feet for wood pole
scaffolds). These paragraphs have been misinterpreted over the years to
mean that scaffolds less than 26 feet high by 30 feet long (25 by 25
for wood pole scaffolds) do not need guys, ties, or braces. Proposed
paragraph (b)(13)(ii) was intended to replace the 26- and 25-foot
vertical rule and require all scaffolds required by the 4 to 1 rule to
have guys, ties, or braces also to have such connections installed at
each end of the scaffold and at horizontal intervals not to exceed 30
feet (measured from one end only).
The following are examples of how this requirement is to be
applied: (a) If a scaffold is five feet wide, 18 feet high and 50 feet
long, no vertical or horizontal ties and braces are required because
the height is less than four times the width and the four to one rule
does not require connections; (b) if the scaffold is five feet wide, 50
feet high, and 25 feet long, ties and braces are required at least at
the 20- and 40-foot levels at both ends of the scaffold (four ties and
braces in all); (c) if the scaffold is five feet wide, 50 feet tall,
and 70 feet long, ties and braces are required at least at the 20- and
40-foot levels. These would be installed starting from either end, at
least at the zero, 30, 60, and 70-foot horizontal distances (eight ties
and braces in all).
The SSFI (Ex. 2-367) disagreed with the 20-foot limit for bracing
intervals in proposed paragraph (b)(13)(i) and suggested a 20-foot
limit for scaffolds 3 feet wide or less, and a 26 foot limit for
scaffolds more than 3 feet wide. In addition, this commenter suggested
that bracing be at bearing locations or as recommended by the
manufacturer. OSHA agrees with this commenter's suggested bracing
intervals, because the Agency believes that properly erected scaffolds
more than 36 inches wide are more stable than those which are narrower,
and has modified this provision of the final rule accordingly.
The SIA (Ex. 2-368) stated:
We are in agreement with the proposed wording used to define the
location of guys and ties as a function of the scaffold base width
dimension. This proposed wording adequately defines where scaffolds
must be guyed or tied to achieve proper scaffold stability. To
correctly transmit the stabilizing forces through the scaffold,
however, the guys or ties must be placed at locations where
horizontal members support both the inner and outer legs. Guying or
tying a scaffold leg at mid span could buckle the leg and cause an
unexpected scaffold failure. To avoid this danger, it is recommended
that the tie be placed at the closest horizontal member above the
4:1 base to height ratio and repeated vertically at locations of
horizontal members every 20 to 26 feet in height thereafter. The top
tie shall be placed no further than a 4:1 base to height ratio from
the top.
OSHA agrees that guys, ties, and braces should be placed at points
of scaffold structural strength, and has modified this provision of the
final rule accordingly. Furthermore, the Agency agrees with the SIA's
recommendation that the top tie, guy, or brace be placed no more than
the 4:1 height to base ratio from the top of the scaffold, and has
modified the provision accordingly. However, OSHA does not agree with
the SIA suggestion that guys, ties and braces be installed at the
closest horizontal member above the 4 to 1 base to height ratio, and
has revised the language of this provision to reflect the Agency's
finding that these components be installed at the closest horizontal
member to the 4:1 height, whether above or below, to maximize
stability.
In addition, the SIA recommended that OSHA require employers to
consider loads due to wind and weather when guying, tying, or bracing
is installed, whenever scaffolds are partially or fully enclosed. The
Agency notes that these matters are addressed in the general capacity
requirements of final rule Sec. 1926.451(a) and in
Sec. 1926.451(f)(13), which requires that wind screens not be used
unless the scaffold has been secured against the forces imposed.
Another commenter (Ex. 2-38) suggested using the same language as
in existing Sec. 1926.451(e)(1), which requires that the height of a
manually propelled mobile scaffold not exceed four times the minimum
base dimension, ``because it is more understandable.'' Also, a
commenter (Ex. 2-40) stated ``since the standard does not address the
issue of cantilevered work platforms (or their effect on stability),
the allowable height to base width ratio of equal to four or less seems
high.''
Another commenter (Ex. 2-23) recommended a ratio of 3 to 1, but
provided no rationale to support its suggestion. OSHA notes that the
final rule 4:1 ratio is consistent with the requirement in ANSI A10.8-
1988, paragraph 4.31, that free-standing scaffolds with height to base
ratios of more than 4:1 be restrained from tipping by guying or other
means.
Based on these concerns, in the final rule OSHA has added paragraph
(c)(1)(iii), which requires that scaffolds with eccentric loads (such
as cantilevered work platforms) be restrained from tipping through the
use of ties, guys, braces or outriggers.
Final rule paragraph (c)(2) requires that supported scaffold poles,
legs, posts, frames, and uprights bear on base plates and mud sills or
other adequate firm foundation. In particular, final rule paragraph
(c)(2)(i) requires that such footings be level, sound, rigid, and
capable of supporting the scaffold in a
[[Page 46043]]
loaded condition without settling or displacement.
In addition, final rule paragraphs (c)(2) (ii) and (iii) provide
that unstable objects shall neither be used to support scaffolds or
platform units, nor be used as working platforms, respectively. The
reason for these requirements is almost self-explanatory: every
scaffold must stand on a firm footing if it is to withstand the load
that employees, equipment, and materials place on it.
Final rule paragraph (c)(2)(iv) provides that front-end loaders and
similar pieces of equipment shall not be used as scaffold supports
unless they have been specifically designed by the manufacturer for
such use. In addition, final rule paragraph (c)(2)(v) requires that
fork-lifts not be used to support scaffold platforms unless the entire
platform is attached to the fork and the fork-lift is not moved
horizontally while the platform is occupied. Both these requirements
relate to the need for solid support for scaffold platforms and reflect
the fact that front-end loaders, fork-lifts and other such equipment
are not generally designed for this purpose.
Paragraph (c)(2) of the final rule is identical to proposed
paragraph (b)(14), except for two provisions, final rule paragraphs
(c)(2) (iv) and (v), which have been added based on input generated by
responses to Issue 3 of the preamble of the NPRM. Proposed paragraph
(b)(14) consolidated existing requirements that scaffold uprights rest
upon a stable, firm, level footing.
Issue 3 asked if OSHA should prohibit the use of cranes, derricks,
forklifts, front-end loaders, and similar pieces of equipment for the
support of scaffold platforms. In addition, OSHA asked what pieces of
equipment should be prohibited and what other related provisions would
be necessary to ensure employee safety.
Several commenters from the Associated General Contractors of
America (AGC) (Exs. 2-20, 2-55, and 2-390) and the ACCSH (Tr. 6/9/87,
pp. 40-41) noted that OSHA had undertaken rulemaking regarding the use
of cranes and derricks to hoist personnel platforms (NPRM published
February 17, 1984, 49 FR 6280). The AGC commenters stated that the
proposed regulations for crane suspended work platforms already
addressed the concerns raised in Issue 3.
Another commenter (Ex. 2-53) called for the development and
issuance of specific crane suspended platform regulations, and one
respondent (Ex. 2-29) commented that the current regulations on crane
suspended work platforms were acceptable.
On August 2, 1988 (53 FR 29116), OSHA issued a final rule
(Sec. 1926.550(g)) which regulates the use of cranes and derricks to
hoist personnel platforms. Therefore, there is no longer a need for
subpart L to address that subject.
Regarding the use of front-end loaders, one commenter (Ex. 2-33)
responded, in part, that ``front-end loaders should not be used to
hoist worker-loaded scaffold platforms'' and added that the ``[u]se of
forklifts for this purpose should be limited in accordance with * * *
OSHA's General Industry Standards for powered industrial trucks, 29 CFR
1910.178(m)(12).'' The same commenter also stated ``If large platforms
are used in this manner, consideration should be given to requiring
bracing of forks to safeguard against tipping or slipping of the truck
or its forks.''
Another commenter (Ex. 2-70) stated simply ``[w]e do not utilize
forms of equipment to support platforms.'' Two other commenters (Exs.
2-367 and 2-368) stated ``the practice of using cranes, derricks, fork-
lifts, etc., [to support scaffold platforms] is unsafe and should be
prohibited.''
One commenter (Ex. 2-5), a manufacturer of heavy-duty materials-
handling equipment, including forklifts and cranes, stated that ``[f]or
years, we have made the users of our equipment aware that these are
intended solely for the handling of materials and not for personnel.''
The commenter went on to say their company recommends that ``OSHA
develop rules prohibiting the use of forklifts, front-end loaders and
similar pieces of equipment for the support of scaffold platforms,''
and provided the following rationale:
This class of equipment depends on a hydraulic cylinder(s) to
lift and hold the load[-]engaging means. When new, the cylinder has
little leakage past the sealing means, usually packings, but it does
have leakage. After use, the leakage increases. This allows the
load[-]engaging means to 'drift' downward, possibly endangering
personnel on the scaffold platform. Additionally, the load[-
]engaging means of a forklift are usually supported on bearings or
sliding members and chains. With use, wear occurs at these points.
If excellent maintenance is not performed, and worn parts [are not]
promptly replaced, sufficient wear can occur which is not evident
when handling heavy loads, since their gravitational mass overcomes
the friction and keeps the chain tight; however, when supporting a
light load such as a scaffold platform, there is insufficient mass
to overcome the friction with the load [-]engaging means left
suspended when the mechanism is lowered, with a sudden drop of the
load [-] engaging means when dislodged. We have knowledge of this
happening at least two times at Cape Kennedy when a work platform
was raised by a 15,000 pound[-]capacity forklift of our manufacture.
Each time serious injury to the man on the platform occurred.
The ACCSH has recommended (Tr. 6/9/87, pp. 32-48) that OSHA
prohibit the use of front-end loaders and other similar earth-moving
equipment for scaffold support. ACCSH also recommended that OSHA
develop rules allowing the use of forklifts as scaffold platforms only
while the equipment is stationary and while proper fall protection is
provided.
Several commenters (Exs. 2-13, 2-20, 2-22, 2-24, 2-54, 2-55, and 2-
390) favored allowing the use of cranes, derricks, front-end loaders,
and forklifts to support scaffold platforms, in general terms. Three
other commenters (Exs. 2-29, 2-33, and 2-176) favored allowing the use
of forklifts, under specified conditions, to support scaffolds.
Three commenters from the AGC (Exs. 2-20, 2-55, and 2-390) stated
that, in certain instances, where access to a work area was difficult
and the work assignment was of short duration, using scaffold framing
might be more hazardous than using equipment for work platform support.
They added that appropriate personal protective equipment could be used
for employee safety in these situations.
Another commenter (Ex. 2-22) opposed the contemplated prohibition,
stating ``[t]here are a variety of field situations in which the use of
such devices is the only safe way to handle a particular problem. Not
only is there no diminution in the safety level afforded to employees
in such situations, but the level of safety may actually be improved.''
Also, a commenter (Ex. 2-24) termed the ``suggestion that cranes,
forklifts, and other equipment could not be used as platform supports''
as ``totally unrealistic.'' The commenter provided some alternatives
and examples (e.g., long ladders) describing them as involving the use
of generally dangerous equipment. The commenter also noted that when
using this equipment as scaffold support, additional protective
measures would be necessary. These measures would include having the
operator at the controls at all times, having railings on platforms
used above 10 feet in height, and providing safety training.
The Boston Cement Masons and Asphalt Layers Union (BCMALU) (Ex. 2-
54) indicated that the use of this equipment to support scaffold
platforms might be practical in certain circumstances. This commenter
also added that employers ``should note the use of this equipment in
their Daily Report and explain why they used it.''
[[Page 46044]]
A carpentry contractor (Ex. 2-176) said that forklift scaffold(s)
with properly constructed scaffold platforms should be permitted,
provided they are equipped with proper railings, and added that ``[i]f
the workers working from the scaffold do not ride up and down, there is
no danger of their falling off.''
One commenter (Ex. 2-29) stated that ``[f]orklift[-]mounted work
platforms might also be acceptable provided suitable requirements and
restrictions are specified.'' Another commenter (Ex. 2-13), expressing
guarded support of the possible prohibition, stated that since this
``equipment is readily available at job sites * * * [it] will continue
to be used to support workers at elevated working locations.'' The same
commenter further suggested that a minimum requirement for the safe use
of such equipment would be to have a competent engineer responsible for
the design and safe use of the resulting scaffold.
After a careful review of the above comments, OSHA finds there is
insufficient reason to totally ban the use of forklifts, front-end
loaders, and other similar equipment as scaffold supports. OSHA notes
that the commenters are in general agreement that all equipment not
specifically designed to support scaffold platforms must not be used.
Accordingly, the Agency has promulgated new paragraphs (c)(2) (iv) and
(v) in the final rule to provide guidance for the safe use of specific
equipment as scaffold supports. In particular, the added provision
requires that, in the case of fork-lifts, the entire scaffold platform
be secured to the forklift. All supported scaffolds, including those
supported by forklifts, front-end loaders and similar pieces of
equipment, must comply with the applicable requirements of
Sec. 1926.451 for capacity, construction, access, use, and fall
protection.
Paragraph (c)(3) of the final rule requires that supported scaffold
poles, legs, posts, frames, and uprights be plumb and braced to prevent
swaying and displacement. This provision, which is identical to
proposed paragraph (b)(15), consolidates existing Sec. 1926.451
(a)(15), (b)(1), (c)(6) and (e)(8), all of which require that uprights
be secure, plumb, and braced to prevent swaying and displacement of the
scaffold.
Paragraph 1926.451(d) Criteria for Suspension Scaffolds
Final rule paragraph (d) sets criteria for the use of suspension
scaffolds. Paragraph (d)(1) of the final rule requires that all
suspension scaffold support devices, such as outrigger beams, cornice
hooks, parapet clamps, and similar devices, rest on surfaces capable of
supporting at least 4 times the loads imposed on them by the scaffold
operating at the rated load of the hoist (or at least 1.5 times the
loads imposed on them by the scaffold operating at the stall load of
the hoist, whichever is greater).
Proposed paragraph (b)(16) required all suspension scaffold support
devices such as outrigger beams, cornice hooks, parapet clamps, and
similar devices, to rest on surfaces capable of supporting the reaction
forces imposed by the scaffold hoist operating at its maximum rated
load. Both the proposed and final rule are based on existing
Sec. 1926.451(h)(9), which requires that outrigger beams rest on
suitable wood bearing blocks. Final rule paragraph (d)(1) differs from
the proposed provision regarding the way in which the load to be
sustained is expressed. The proposed rule used the term ``maximum rated
load'' instead of the final rule's terms ``rated load of the hoist''
and ``stall load'' of the hoist.
Three commenters (Exs. 2-64, 2-367 and 2-516) recommended a 4 to 1
safety factor based on the rated load of the hoist. Another commenter
(Ex. 2-41) stated that reaction force should include all forces, not
just those from the hoist, and indicated that some safety factor was
needed. The Agency agrees that a clarification is warranted here, and
has modified the final rule to reflect this input. In addition, the
text has been modified to be consistent with final rule Secs. 1926.451
(a)(2) and (a)(4). The Agency concludes that this is necessary in order
to adequately address the issue of the hoist reaching its stall load
when the scaffold strikes an obstruction. OSHA has determined that the
hoist stall capacity needs to be greater than the hoist rated capacity
so that the rigging system will be able to support the loads imposed by
obstructions as well as the load being lifted. This matter is addressed
in greater detail above, in relation to final rule Sec. 1926.451(a)(1).
Final rule paragraphs (d)(2), (d)(3) and (d)(4) set requirements
for outrigger beams used with suspension scaffolds. Paragraph (d)(2) of
the final rule requires that suspension scaffold outrigger beams, when
used, be made of structural metal, or equivalent strength material, and
be restrained to prevent movement. This is identical to proposed
paragraph (b)(17), except as discussed below. The proposal was based on
existing Secs. 1926.451(h)(4) and (k)(8).
The SIA (Ex. 2-368) stated that if the intent of proposed paragraph
(b)(17) was to prohibit the use of wood outrigger beams, the Agency
should simply say so. The proposed language clearly indicated that
outrigger beams must be made of structural metal. However, upon further
consideration of this provision, OSHA believes that other materials
should be allowed if their strength and other pertinent characteristics
are equivalent to those of structural metal. The Agency has therefore
revised the proposed rule accordingly. This revision is in line with
the Agency's policy to permit alternative materials or practices which
provide equivalent protection to employees. Also, OSHA has added the
words ``when used'' to indicate clearly that the provision does not
require outrigger beams to be used but only applies when outrigger
beams are used.
Final rule paragraph (d)(3) sets requirements for the stabilization
of outrigger beams. The introductory language of the paragraph requires
that outrigger beams be secured directly to the supporting surface or
be stabilized using counterweights, except that masons' multi-point
adjustable suspension scaffolds shall not be stabilized by
counterweights. The rule does not allow counterweights for stabilizing
such masons' suspension scaffolds because, with the large loads often
placed on masons' multi-point adjustable suspension scaffolds and the
large counterweights that would be necessary to anchor such systems,
OSHA is concerned that the supporting roof or floor would become
dangerously overloaded.
Final rule paragraph (d)(3) is identical to proposed paragraph
(b)(18), except for a few minor editorial changes as described below.
The final rule clarifies existing Secs. 1926.451 (h)(4) and (j)(5),
which require simply that outriggers be securely fastened or anchored.
Counterweights are not addressed in the existing standard. OSHA has
determined that it is necessary to set criteria for counterweights in
the final rule, however, because counterweights are often the only way
to anchor an outrigger beam without damaging the supporting surface.
Paragraph (d)(3)(i) provides that direct connections shall be
evaluated by a competent person who affirms, based on that evaluation,
that supporting surfaces can support the anticipated loads. In
addition, the paragraph requires masons' multi-point adjustable
suspension scaffold connections to be designed by an engineer
experienced in such scaffold design. OSHA anticipates that compliance
with these provisions will ensure that roof or floor decks are capable
of supporting the loads to be imposed.
[[Page 46045]]
Final rule paragraphs (d)(3)(ii) through (d)(3)(v) require that
counterweights be made of non-flowable material; be specifically
designed for use as scaffold counterweights; be secured to outrigger
beams to prevent accidental displacement; and not be removed from an
outrigger beam until the scaffold is disassembled, respectively. These
requirements are necessary to ensure that counterweights are used only
for their intended purpose and are not displaced or removed
prematurely.
Final rule paragraphs (d)(3)(vi) through (d)(3)(x) set requirements
for securing outrigger beams. In particular, outrigger beams not
stabilized by direct connections to the supporting surface shall be
secured by tiebacks (paragraph (d)(3)(vi)). Tiebacks must be as strong
as the suspension ropes (paragraph (d)(3)(vii)), be secured to a
structurally sound anchorage (paragraph (d)(3)(ix)), and be installed
perpendicular to the structure unless opposing angle tiebacks are
installed (paragraph (d)(3)(x)). In addition, paragraph (d)(3)(viii)
requires that outrigger beams be placed perpendicular to their bearing
support, with the exception described more fully below.
With regard to proposed paragraph (b)(18)(i) (paragraph (d)(3)(i)
in the final rule), a commenter (Ex. 2-40) stated ``we believe that
improper connections are almost always responsible for the failure of
scaffolds. Therefore, criteria for torsion strength evaluation of
bolted (direct) connections should be included in the standard.'' OSHA
believes that the corresponding requirement in final rule paragraph
(d)(3)(i) for evaluation of direct connections by a competent person
will provide adequate assurance that those connections are designed and
made appropriately, because the competent person must have the ability
to identify any problems with the direct connections and the authority
to have any problems corrected.
Proposed paragraph (b)(18)(ii) (paragraph (d)(3)(ii) in the final
rule) required that counterweights be made of non-flowable solid
material. That, in effect, prohibited the practice of using sandbags or
water-filled buckets as counterweights. The reason for the prohibition
is that counterweights are easily displaced and may leak. Final rule
paragraph (d)(3)(ii) is virtually identical, except that the word
``solid'' has been deleted, because that term is redundant with the
term ``non-flowable'', and a sentence has been added that explicitly
prohibits the use of sand, gravel and other similar material as
counterweights.
A commenter (Ex. 2-41) stated that the proposed paragraph would
cause confusion, inquiring whether, if five 70 pound weights are
considered ``solid,'' 350 one pound weights also would be considered
``solid''? The Agency would consider five 70 pound weights as meeting
this requirement, because objects of this weight would be unwieldy and
less prone to dislocation. However, 350 one pound weights would not
meet this requirement because their light weight would make them more
prone to being dislocated, thus possibly compromising their
effectiveness as a counterweight. OSHA has added the sentence ``Sand,
gravel, and similar materials that can be easily dislocated shall not
be used'' to indicate more clearly what materials are not allowed for
use as counterweights.
Paragraph (d)(3)(iii) of the final rule requires that
counterweights be specifically designed for use as counterweights. This
provision, which was not part of the proposed rule, has been added in
response to input received regarding Issue 26 in the preamble of the
NPRM. That Issue asked if OSHA should require that counterweights be
designed for no other purpose than to counterweight the system, thereby
prohibiting the use of construction materials, such as concrete masonry
units, rolls of felt, etc., as counterweights.
One commenter (Ex. 2-22) opposed requiring that counterweights be
designed for no other purpose than to counterweight the system. This
commenter stated that such a requirement would be unnecessarily costly.
This commenter also stated ``So long as the material used meets the
objective of the safety requirement, there is no need to cause the
expenditure of money on specific materials that do not enhance the
safety of the employee * * *''
Several commenters (Exs. 2-13, 2-29, 2-43, 2-53, 2-54, 2-64, 2-367,
2-368 and 2-465) supported a requirement that counterweights be
specifically designed for no other purpose than to counterweight the
system. These commenters also supported a ban on the use of
construction material as counterweights. The SIA (Ex. 2-368) added that
such a requirement would be practical, feasible, of negligible cost and
would prevent accidents which occur when construction materials used as
counterweights are removed for other purposes.
Another commenter (Ex. 2-13) stated:
Counterweights should be designed for their specific use and
permanently marked with their weight otherwise they are worthless.
Construction material, of any kind, should be banned for use as
counterweights. There is no assurance that proper counterweighting
is being accomplished with construction materials. Also, the
material could be removed for use by others, thus providing an
unstable condition.
Two commenters (Exs. 2-64 and 2-367) stated that there should be a
requirement that counterweights be identified or marked. The SSFI (Ex.
2-367) recommended that ``each counterweight be identified as to its
weight'' and should also ``have the ability to be fastened directly to
the outrigger system.'' Another commenter (Ex. 2-64) wanted
counterweights to be ``clearly marked with their actual weight
(stamped, painted, etc.), so that workers will use the proper amount of
weight.''
In addition, a commenter (Ex. 2-8) stated ``[c]onstruction
materials should not be use[d]. We have seen masons remove block used
as counterweight.''
Also, the ACCSH (Tr. pp. 188-190, 6-9-87) recommended that
counterweights be designed for no other purpose than to counterweight
the system. One member stated ``Certainly OSHA should require
counterweights be designed for no other purpose. It seems to me that
the same day I first read this question I received from OSHA a copy of
`Fatal Facts' that involved this very issue.''
After carefully considering the above comments and the ACCSH
recommendation, OSHA has determined that it is reasonably necessary to
require that counterweights be designed for no other purpose than to
counterweight the system, and to prohibit the use of construction
materials as counterweights. In addition, OSHA has determined that it
is appropriate to require the marking of counterweights with their
weights because that information is needed for the proper design,
selection and installation of counterweights.
Proposed paragraph (b)(18)(iii), which required that counterweights
be connected to outrigger beams by mechanical means, is identical to
final rule paragraph (d)(3)(iv), except that the phrase ``to prevent
accidental displacement'' has been added to the final rule to clarify
the Agency's regulatory intent. The BCMALU (Ex. 2-54) recommended that
the Agency clarify the reason for this provision. The Agency agrees and
has revised the provision accordingly.
Proposed paragraph (b)(18)(iv) required that counterweights not be
removed from a scaffold until the scaffold is disassembled. Final rule
paragraph (d)(3)(v) is identical to the proposed paragraph, except that
the
[[Page 46046]]
final rule specifies that the counterweights may not be removed from
the ``outrigger beam'', rather than from the ``scaffold.'' One
commenter (Ex. 2-41) pointed out that counterweights used with
suspension scaffold outrigger beams are not placed on the scaffold, as
stated in the proposed rule, but are installed on the outrigger beam
above. The Agency agrees, and has revised the provision accordingly.
Proposed paragraph (b)(18)(v) required outrigger beams to be
secured by tiebacks equivalent in strength to the suspension ropes.
This provision was intended to provide a backup system in case the
counterweights became displaced. Although tiebacks alone may not keep a
scaffold from tipping, they will keep the system from falling to the
ground and from causing a progressive failure of nearby scaffolds and
scaffold sections. The intent of the proposed paragraph has been
carried forward in final rule paragraphs (d)(3)(vi) and (vii), which
require the use of tiebacks when direct connections are not used, and
require tieback strength equivalent to that of the suspension ropes,
respectively.
The SSFI and the SIA (Ex. 2-367 and 2-368) noted that outrigger
beams which are bolted to the structure become part of the structure
and do not require tiebacks. The Agency agrees that only
counterweighted outrigger beams need to be secured with tiebacks and
has incorporated appropriate language into paragraphs (d)(3)(vi) and
(d)(3)(vii) accordingly.
In addition, final rule paragraph (d)(3)(viii) requires that
outrigger beams be placed perpendicular to the face of the structure,
except that, where the employer establishes that such placement is
prevented by obstructions, the outrigger shall be placed as near to the
perpendicular as possible and shall be secured using opposing angle
tiebacks. This provision has been added as a partial response to a
commenter (Ex. 2-41) who stated that requiring tiebacks to be installed
parallel to the centerline of the beam, as required by proposed
paragraph (b)(18)(vii), is only safe when the beam is perpendicular to
the edge. OSHA agrees with this comment because a non-perpendicular
beam/tieback arrangement creates a pendulum effect that could endanger
employees. However, the SIA (Ex. 2-368) has pointed out that there may
be circumstances where obstructions prevent the outrigger beam from
being placed perpendicular to the edge. The SSFI and the SIA (Exs. 2-
367 and 2-368) suggested that, in such cases, opposing angle tiebacks
be required. OSHA agrees that opposing angle tiebacks are appropriate
where obstructions prevent perpendicular placement of outriggers, and
has revised the final rule language accordingly.
Proposed paragraphs (b)(18) (vi) and (vii) required that tiebacks
be secured to structurally sound anchorages and that they be parallel
to the outrigger beam. Those provisions correspond to final rule
paragraphs (d)(3) (ix) and (x). OSHA has revised this language, drawing
on examples in the preamble of the NPRM, to provide more specific
direction regarding what constitutes a structurally sound anchorage.
Three AGC commenters (Exs. 2-20, 2-55 and 2-390) stated that the
OSHA interpretation of what is considered an acceptable point of
anchorage (51 FR 42686) was too strict and that the Agency should
permit the use of any available roof structural anchor points since
they are only accommodating a back-up or secondary support system. The
Agency disagrees with this position because the secondary support
system must be capable of providing adequate support in the event of
rigging failure. The revised final rule paragraph specifically
identifies structural members of the building or structure as
appropriate anchor points, and identifies standpipes, vents, other
piping systems, and electrical conduit, as structural elements that do
not provide appropriate anchorages.
Proposed paragraph (b)(18)(vii) required that tiebacks be installed
parallel to the centerline of the beam. The proposed language has been
revised in final rule paragraph (d)(3)(x) to recognize that opposing
angle tiebacks are acceptable alternative means of installation. In
addition, OSHA has replaced the proposed term ``parallel'', with the
term ``perpendicular'' for the sake of clarity.
A commenter (Ex. 2-29) stated ``since tieback anchorages are not
always available exactly where needed, perhaps the wording of these
requirements should be revised to allow tiebacks to be at an angle,
e.g., not to exceed 10 degrees from the centerline of the outrigger * *
*.'' OSHA acknowledges that anchorages are not always conveniently
located and that there may be circumstances where it is necessary to
install the tieback at an angle. However, OSHA believes that when this
is done, it is also necessary to require an opposing angle tieback to
be used so that the pivot radius of the beam is minimized.
Consequently, single tiebacks installed at an angle are not allowed by
the final rule.
Paragraph (d)(4) of the final rule specifies the construction
requirements for outrigger beams used with suspension scaffolds. This
provision requires that suspension scaffold outrigger beams be:
provided with stop bolts or shackles at both ends; securely fastened
together with the flanges turned out when channel iron beams are used
in place of I-beams; installed with all bearing supports perpendicular
to the beam center line; and set and maintained with the web in a
vertical position. In addition, when an outrigger beam is used, the
shackle or clevis with which the suspension rope is attached to the
outrigger beam shall be placed directly over the hoisting machine,
i.e., over the center line of the stirrup. (These requirements are
found in paragraphs (d)(4)(i) through (d)(4)(v).)
These requirements are effectively identical to those in proposed
paragraph (b)(19). The SIA (Ex. 2-368) recommended that OSHA drop the
word ``single'' from proposed paragraph (b)(19)(v) because this
requirement applied to all outrigger beams, not just to ``single
outrigger beams''. The Agency agrees, and has revised this provision of
the final rule accordingly.
Final rule paragraph (d)(5) sets requirements for suspension
scaffold support devices other than outrigger beams. These devices
include cornice hooks, roof irons, parapet clamps, or similar devices.
Under this provision, those devices must be: made of steel, wrought
iron, or materials of equivalent strength; supported by bearing blocks;
secured against movement by tiebacks installed at right angles to the
face of the building or structure unless opposing angle tiebacks are
installed and secured to a structurally sound point of anchorage on the
building or structure (sound points of anchorage include structural
members, but do not include standpipes, vents, other piping systems, or
electrical conduit); and tiebacks shall be equivalent in strength to
the strength of the hoisting rope.
Final rule paragraph (d)(5) is identical to proposed paragraph
(b)(20), except that some minor editorial changes have been made for
the sake of clarity. In particular, OSHA has revised proposed paragraph
(b)(20)(i), which specified ``mild steel, wrought iron, or equivalent
materials,'' by deleting the word ``mild'' and changing ``equivalent
materials'' to ``materials of equivalent strength.'' These revisions
are based, in part, on input from a commenter (Ex. 2-41), who indicated
that the term ``mild steel'' is not defined in readily available
sources. The other change was made to indicate clearly that the
strength of the specified materials was the characteristic by which
`equivalence' would be gauged.
[[Page 46047]]
Proposed paragraph (b)(20)(iii) required the use of tiebacks,
installed at right angles to the face of the structure wherever
possible; secured to a structurally sound portion of the building; and
equivalent in strength to the hoisting rope. As stated in the preamble
to the NPRM (51 FR 42686), vents, standpipes, other piping systems, and
electrical conduits are not acceptable points of anchorage because they
are often made of materials that cannot support the loads that would be
imposed on them if the support device were to fail. OSHA has revised
the proposed provision so that final rule paragraph (d)(5)(iii) allows
opposing angle tiebacks, as well as tiebacks at right angles, and has
incorporated the NPRM preamble list of unacceptable anchorage points to
facilitate compliance. In addition, the Agency has relocated the
requirement for tieback strength equivalent to that of the hoisting
rope to a separate provision (final rule paragraph (d)(5)(iv)).
Two commenters (Exs. 2-64 and 2-368) suggested a requirement that
devices covered by proposed paragraph (b)(20) be marked to indicate
their capacity. OSHA has not done so because the Agency believes that
such markings are not necessary given the capacity requirements set in
final rule Sec. 1926.451(a).
Paragraph (d)(6) of the final rule specifies the minimum length of
suspension rope to be used with different kinds of hoists. In
particular, winding drum hoists are required to have at least four
wraps of suspension rope at the lowest point of scaffold travel. All
other types of hoists are required to have suspension rope long enough
to lower scaffolds to the level below, without having the rope end pass
through the hoist, or to have the rope end configured or provided with
means so that the end does not pass through the hoist.
This provision, which is identical to proposed paragraph (b)(21),
elicited one comment. The BCMALU (Ex. 2-54) recommended that OSHA
require that the rope be long enough to allow the scaffold to be
lowered to the lowest point on the job-site without the rope passing
through the hoist or that the scaffold be initially set up at the
highest point at which it will be used on that job-site. OSHA believes
that the proposed provision adequately addressed the issue of rope run-
through and, accordingly, has not made the suggested revision in the
final rule.
Final rule paragraph (d)(7) states ``The use of repaired wire rope
as suspension rope is prohibited.'' This provision differs from
proposed paragraph (b)(22), which stated ``The repairing of wire
suspension rope is prohibited.'' The proposed requirement was based on
OSHA's view that there is no way to determine the strength capacity of
a repaired wire rope without the danger of over-stressing the repair
and thus rendering the rope unsafe for use on scaffolds. The Agency
recognizes that the proposed rule did not clearly state OSHA's intent.
The act of repairing wire suspension rope is not in itself hazardous.
OSHA is, however, concerned that repaired rope not be used to suspend a
scaffold. Accordingly, OSHA has revised this provision to prohibit the
use of repaired wire rope as suspension rope.
Paragraph (d)(8) of the final rule provides that wire suspension
ropes shall not be joined together except through the use of eye splice
thimbles connected with shackles or coverplates and bolts. This is
virtually identical to proposed paragraph (b)(23). This provision,
which was not in OSHA's existing scaffold standard, reflects OSHA's
determination that the specified measures are the only acceptable ways
to connect wire ropes without significantly affecting rope strength.
The SSFI and the SIA (Exs. 2-367 and 2-368) suggested revision of
the proposed text to read ``wire suspension ropes shall not be joined
together except through the use of eyesplice thimbles connected with
shackles or cover plates and bolts.'' OSHA agrees that the suggested
phrase ``through the use of eye splice thimbles connected'' expresses
the Agency's intent more effectively than the proposed phrase ``by
eyesplicing'' and has revised the language of the final rule
accordingly. The SIA further indicated that this requirement should
apply only to wire suspension ropes used with manual hoists. However,
the Agency concludes that final rule paragraph (d)(8) is applicable to
the joining of all wire suspension rope, not just that which is used
with manual hoists, because compliance with that provision is necessary
to ensure that the wire ropes on all suspended scaffolds are rigged
properly. Therefore, OSHA is not making the suggested change.
Paragraph (d)(9) of the final rule provides that the load end of
wire suspension ropes shall be equipped with proper size thimbles and
secured by eye splicing or equivalent means. This provision is
identical to proposed paragraph (b)(24), which was based on existing
Sec. 1926.451(h)(10) and existing Sec. 1926.451(j)(7).
Final rule paragraph (d)(10) requires that ropes be inspected for
defects by a competent person prior to each workshift and after every
occurrence which could affect a rope's integrity. In addition,
paragraph (d)(10) provides that wire rope shall be replaced if the rope
has any physical damage which impairs its function and strength; any
kinks that might impair the tracking or wrapping of rope around the
drum(s) or sheave(s); six randomly distributed broken wires in one rope
lay or three broken wires in one strand in one rope lay; abrasion,
corrosion, scrubbing, flattening or peening causing loss of more than
one-third of the original diameter of the outside wires; evidence of
any heat damage resulting from a torch or any damage caused by contact
with electrical wires; or evidence that a secondary brake has been
activated during an overspeed condition and engages the suspension rope
(paragraphs (d)(10) (i) through (vi)).
Proposed paragraph (b)(25) provided simply that ``Defective or
damaged ropes shall not be used as suspension ropes or drop lines.''
The proposed language was based on existing Sec. 1926.451(w)(5), which
prohibits damaged ropes from being used on float or ship scaffolds. The
danger of a broken line is a problem not confined to float or ship
scaffolds, so OSHA has extended this provision in the final rule to
cover all suspended scaffolds.
The one comment (Ex. 2-38) on the proposed provision pointed out
that guidelines indicating when rope would be considered to be
defective should be provided. The Agency agrees that employers need to
know what OSHA means by ``defective or damaged rope''. Accordingly,
final rule paragraph (d)(10) incorporates the language of ANSI A10.8-
1988, paragraph 6.7.10, because OSHA finds that those consensus
provisions represent good industry practice.
Paragraph (d)(11) of the final rule requires that swaged
attachments or spliced eyes on wire suspension ropes not be used unless
they are made by the wire rope manufacturer or a qualified person. This
provision is essential to ensure the strength and integrity of such
attachments as eyes and is identical to proposed paragraph (b)(26).
Paragraph (d)(12) of the final rule requires that, when wire rope
clips are used on suspension scaffolds, there shall be a minimum of 3
wire rope clips installed, with the clips a minimum of 6 rope diameters
apart; employers shall follow the manufacturer's recommendations when
installing clips, retightening clips after initial loading, and
inspecting and retightening clips at the start of each workshift; U-
bolt clips (a variety of wire rope clip) shall not be used at the point
of suspension for any
[[Page 46048]]
scaffold hoist; and when U-bolt clips are used, the U-bolt shall be
placed over the dead end of the rope, and the saddle shall be placed
over the live end of the rope.
Proposed paragraph (b)(27) simply stated ``When wire rope clips are
used on suspension scaffolds, they shall be retightened after initial
loading and shall be inspected and retightened periodically
thereafter''. OSHA believed at the time of the proposal that such
performance language conveyed the requirements necessary to ensure that
clips were installed and retightened properly.
Two commenters (Exs. 2-23 and 2-54) recommended that OSHA specify
the minimum number of clips required. In particular, one commenter (Ex.
2-23) recommended a minimum of 3 clips spaced at least 6 rope diameters
apart, with the U-bolt over the dead end of the wire rope. This
commenter added that the clips must not be staggered.
The SIA (Ex. 2-368) recommended that the clips be tightened to the
manufacturer's recommended torque. Another commenter (Ex. 2-64)
suggested that only ``J'' type clamps be used on suspension scaffold
lines and that the clips be inspected and retightened at the start of
each workshift thereafter.
The Agency agrees that more specific requirements are needed so
that employers know how to install and retighten wire rope clips. OSHA
believes that the requirements of ANSI A10.8-1988, paragraph 6.7.11.3,
appropriately address the concerns raised by commenters, and has
incorporated those provisions into paragraph (d)(12) of the final rule.
In addition, the Agency agrees that a minimum of 3 clips spaced at
least 6 rope diameters apart is necessary for safe rigging when wire
rope clips are being used. OSHA notes that several drawings in ANSI
A10.8-1988 which depict the proper rigging of suspension scaffolds show
three wire rope clips on the suspension ropes.
Final rule paragraph (d)(13) requires that suspension scaffold
power-operated hoists and manually operated hoists be of a type tested
and listed by a qualified testing laboratory. This is virtually
identical to proposed paragraph (b)(28), except that OSHA has revised
the proposed terms ``mechanically powered'' and ``manually powered''
hoists to read ``power operated hoists and manually operated hoists''
in the final rule. This revision brings paragraph (d)(13) into line
with the language of ANSI A10.8-1988, paragraph 6. This provision
consolidates existing provisions Secs. 1926.451 (h)(2), (i)(3), (j)(2),
and (k)(1).
Paragraph (d)(14) of the final rule requires that gasoline-powered
equipment and hoists not be used on suspension scaffolds. This
provision is similar to proposed paragraph (b)(29), except that the
final rule now prohibits all gasoline-powered equipment or hoists, not
just gasoline powered hoists.
The proposed provision was based on existing Sec. 1926.451(k)(2)
which allows units to be either electrically or air motor driven. OSHA
has determined that gasoline hoists pose unacceptable fire hazards,
given the confined area of a suspended scaffold and the difficulties
employees would face trying to escape the scaffold if the hoist was
incapacitated and on fire.
The BCMALU (Ex. 2-54) strongly recommended that OSHA prohibit the
use of all gasoline-powered equipment and hoists on suspension
scaffolds because of the high potential for fire. The commenter cited
an example of an accident in which two employees were severely burned
using a gasoline-powered water blaster. The Agency agrees with this
concern and has revised the provision in the final rule accordingly.
Paragraph (d)(15) of the final rule requires that gears and brakes
of power operated hoists used on suspension scaffolds be enclosed. This
is virtually identical to proposed paragraph (b)(30), except a change
in terminology has been made (``mechanically powered'' to ``power
operated''), consistent with the changes made and discussed above under
paragraph (d)(13). The proposed rule was based on existing
Sec. 1926.451(k)(3).
Final rule paragraph (d)(16) provides that, in addition to the
normal operating brake, suspension scaffold power operated hoists and
manually operated hoists shall have a braking device or locking pawl
which engages automatically when a hoist makes either of the following
uncontrolled movements: an instantaneous change in momentum or an
accelerated overspeed. This provision is different from proposed
paragraph (b)(31), which required a brake or pawl to automatically
engage ``when the normal speed of descent of the hoist is exceeded.''
The proposed provision was based on existing Sec. 1926.451(k)(4) but
differed from the existing standard in that it applied to manual as
well as to powered hoists.
One commenter (Ex. 2-8) stated that OSHA should modify the proposed
provision to specifically address an instantaneous change in momentum
and an accelerated overspeed. OSHA agrees that the suggested revision
is appropriate, noting that ANSI A10.8-1988, paragraph 6.3.4.1
addresses both instantaneous stopping type secondary brakes and
deceleration type secondary brakes. The Agency has revised the final
rule's language accordingly.
The SSFI and the SIA (Exs. 2-367 and 2-368) recommended that OSHA
apply this requirement only to powered hoists. OSHA disagrees with
these commenters, noting that, as written, the provision requires a
braking device (for powered hoists) or a locking pawl (for less
sophisticated or manual hoists). The Agency concludes that these
precautions are necessary on all suspension scaffold hoists and,
accordingly, has not made the suggested revision.
Paragraph (d)(17) of the final rule provides that ``Manually
operated hoists shall require a positive crank force to descend.'' This
is the same requirement as proposed paragraph (b)(32), except the term
``manually operated hoists'' replaces the proposed term ``manually-
powered hoists'' for the same reasons as discussed above in relation to
final rule paragraphs (d)(13) and (d)(15).
Issue 27 in the preamble to the NPRM sought comments regarding
proposed Sec. 1926.451 (b)(32) (paragraph (d)(17) of the final rule)
which addresses means of preventing ``free-running'' of hoists during
descent. OSHA's view was that compliance with the proposed paragraph
would preclude this dangerous condition.
One commenter (Ex. 2-31), whose remarks related solely to pumpjack
scaffolds, stated that ``[u]nder ordinary circumstances, free[-]running
does not occur during descent of a pumpjack.''
The ACCSH recommended requiring a positive crank force to lower a
scaffold (Tr. 190-191, 6/9/87). The SSFI (Ex. 2-367) and the SIA (Ex.
2-368) commented that the proposed provision would preclude the use of
a ``boat winch'' type system. The SIA further noted that, to their
knowledge, free-running hoists are ``rare in the marketplace.'' They
added that the requirement was feasible and practical and would involve
negligible additional cost. NIOSH (Ex. 2-40) agreed with the proposed
provision. The BCMALU (Ex. 2-54) stated that although a positive crank
force might be slower than a free-running hoist, it would be safer
which ``is the name of the game, safety.''
One commenter (Ex. 2-29) stated that a positive crank force should
be required for hoists used to lower manually-powered scaffolds.
Another commenter (Ex. 2-53) stated that the proposed requirement is
needed. In addition, a commenter (Ex. 2-64) stated
[[Page 46049]]
that a positive crank force is essential unless the descent speed can
be controlled by some other means.
After carefully considering the above comments and the ACCSH's
recommendation, OSHA has determined that this requirement is necessary
to eliminate the dangerous condition of ``free-running'' hoists during
descent and to ensure employee safety.
Final rule paragraph (d)(18) provides that two-point and multi-
point suspension scaffolds shall be tied or otherwise secured to
prevent them from swaying, as determined necessary based on an
evaluation by a competent person. This paragraph requires, in addition,
that window cleaners' anchors not be used for the purpose of preventing
swaying. This prohibition is based on the fact that window cleaners'
anchors are not designed for the load that could be imposed. This
provision was not part of the proposed rule.
Issue 7 in the preamble of the NPRM asked if the existing
Sec. 1926.451(i)(9) and proposed Sec. 1926.452(p)(5) requirement that
employers secure two-point adjustable suspension scaffolds to prevent
swaying should be extended to cover all suspended scaffolds.
Six commenters (Exs. 2-13, 2-22, and 2-43, 2-471, 2-494, and 2-516)
expressed some measure of support for the idea of extending this
provision to cover all suspended scaffolds.
One commenter (Ex. 2-13) stated as follows:
All exterior scaffolds should be stabilized at each work
location or provide a method of stabilization as described in OSHA
1910.66 [powered platform standard for General Industry] or by
Intermittent Stabilization, as contained in OSHA STD 1-3.3. In
addition, all new buildings over 35 feet in height should be
provided with a permanent engineered methods or means of rigging.
The vast majority of suspended scaffold accidents that do occur
are due to deficient rigging.
A later comment from the same individual (Ex. 2-494) stated
``[w]ith prior planning, there are ways that all scaffolds can be
stabilized * * * Unstabilized scaffolds are a hazard to the occupants,
other workers, and pedestrians below.''
Another commenter (Ex. 2-471) stated as follows:
Any shear wall, with the technology available since November
1982, as described in OSHA Instruction STD 1-3.3, can be made safe
by the installation and the use of Intermittent Stabilization
Building Anchors, to prevent a suspended scaffold from being
displaced by wind forces.
Merely providing perimeter protection and separate safety lines
will not prevent the scaffold and its occupants from being blown
about, being upset, or violently contacting the structure being
serviced, all of which could cause death or injury.
Two commenters (Exs. 2-64 and 2-368) stated that it is neither
possible nor practical to tie in all suspended scaffolds. They stated
that there are many job situations (e.g., sheer or glass walls, or no
wall at all) where stabilization would not work because there are no
points where tie-ins can be made. OSHA acknowledges that there are
circumstances where suspension scaffolds used in construction have no
structure against which to be secured. The present rulemaking takes
into account the likelihood that ``permanent engineered methods'' or
``intermittent stabilization building anchors'' will not be in place
during construction operations. The applicability of Sec. 1910.66 and
OSHA STD. 1-3.3 is limited because they apply to post construction
scaffold activities (such as window washing and light building
maintenance).
The BCMALU (Ex. 2-54) simply expressed support for the existing
requirement that two-point suspension scaffolds be secured to prevent
swaying.
Three commenters from the AGC (Exs. 2-20, 2-55, and 2-390) said
that single-point suspension scaffolds do not have a tendency to sway.
They explained that ``[s]waying generally occurs on two-point
suspensions because of uncoordinated movements by two or three
employees working on the platform as well as the fact that larger
platforms permit movement by employees. This is not the case in single-
point suspensions.''
Another commenter (Ex. 2-29) stated that ``[s]ingle-point
boatswains' platforms should not be included [under this provision] * *
* since this would greatly restrict their use.''
OSHA agrees with the AGC commenters that single-point scaffolds
should not be covered by this provision because, by their nature, they
do not have a tendency to sway. Single-point scaffolds generally
consist of a seat or a small cage which prevents employee movement and
scaffold swaying, and therefore, do not pose the same hazard as multi-
point scaffolds.
One commenter (Ex. 2-41) stated ``based on much research, it is my
opinion that the primary purpose for suspended scaffold restraint on a
platform which has no open sides is to prevent the walking-working
surface from becoming unstable during normal work activities. The
restraint also closes the open side during work activities * * *'' In
addition, the SIA (Ex. 2-368) noted that ``[w]here the work platform is
provided with guardrails on all sides and workers are protected by * *
* safety lines, the protection should be adequate.'' Another commenter
(Ex. 2-516) noted that ``[t]here may be limited situations where
suspended scaffolds for construction cannot be tied into the building
or structure. However, this is not a reason for not having [fall]
protection. Any suspended platform not tied in then definitely needs
guardrails on all four sides.''
In response to Issue 7, the ACCSH recommended (Tr. 79-87, June 9,
1987) that, where determined necessary by a competent person, all
suspended platforms be secured to prevent swaying. The Advisory
Committee indicated that the expertise of the competent person would
enable the employer to determine the situations where it was
appropriate to secure suspended scaffolds against swaying.
After careful consideration of the comments received, OSHA has
decided not to require the use of tie-ins to protect single-point
suspended scaffolds from swaying. As noted above, this type of scaffold
generally consists of a seat or small cage which limits employee
movement and swaying. However, the Agency does agrees with the ACCSH
that the expertise of a competent person will enable the employer to
determine when it is appropriate to secure two-point and multi-point
suspended scaffolds and has worded the final rule accordingly.
In addition, Issue 18 in the preamble of the NPRM asked if there
should be a height limit above which single and two-point adjustable
suspension scaffolds may not be used, and if so, what the height should
be, and why.
Four commenters (Exs. 2-20, 2-55, 2-69, and 2-390) responded by
asking ``what type of equipment could be used above the limit that
would be safe, practical, feasible and economical?'' One commenter (Ex.
2-69) added that the hoist lifting capacity is the only height
limitation for this type of scaffold. Another commenter (Ex. 2-13)
agreed with that point and stated that OSHA should not try to limit the
working height of suspension scaffolds. Two other commenters (Exs. 2-22
and 2-64) simply agreed that there should not be a height limitation.
One of those commenters (Ex. 2-22) added that following ``the safety
standards'' eliminates unsafe conditions.
Some Issue 18 commenters (Exs. 2-41, 2-54, 2-312) felt that the
height of a suspended scaffold was not a problem. One commenter (Ex. 2-
41) stated that a ``height limit in construction should not be a factor
in the safe use of equipment.'' As an example, he observed that
``single-point scaffolds
[[Page 46050]]
have been used in 950 foot elevator shafts for elevator installation *
* *'' The BCMALU (Ex. 2-54) indicated that a greater height would make
workers more aware of hazards and thus more cautious. The commenter
also stated ``[i]t seems most employers and employees are more safety
conscious in high places and careless at 5 to 10 feet from the
ground.'' In addition, he commented that he did not see how OSHA could
restrict use of this equipment because there are situations where these
types of scaffolds are the only equipment that can be used. Also, a
commenter (Ex. 2-312) stated that ``[w]e have outfitted chimney workers
for years so they could work on chimneys that stood 800 to 1000 feet in
height. Never a single accident reported.'' The commenter explained
that descent devices and the chair board systems use ``one friction
principle'' and for these, more rope means more friction with which to
slow descent. In addition, the commenter recommended that subpart L
require that all rope [for these suspended scaffolds] be continuous
length of line, without splices. The commenter further noted that this
requirement would limit the height somewhat.
The SSFI and the SIA (Exs. 2-367 and 2-368) expressed opposition to
a height limitation for suspended scaffolds and recommended that ``the
equipment should be designed by competent persons who will take into
consideration all the hazards involved, thereby providing safe
equipment for the specific job function.'' In addition, the SIA (Ex. 2-
368) stated that suspended scaffolds are practical and feasible at any
height when properly installed and used, and that the height limitation
``would be the ability of the hoist(s) to raise and lower the work
platform.'' Another commenter (Ex. 2-465) stated that this equipment
should be designed by a competent person ``who is thoroughly familiar
with the hazards involved.'' That commenter also stated that suspended
scaffolds are the most feasible and safest methods to use for work on
smoke stacks, towers, and water tanks.
At its meeting of June 9, 1987, the ACCSH responded to Issue 18 by
reiterating the position they previously adopted under Issue 7
regarding two-point suspended scaffolds. (Issue 7 is discussed above in
reference to paragraph (d)(18) of the final rule.) While the ACCSH did
not favor adopting a height limitation for single- and two-point
adjustable suspended scaffolds, they did recommend that these types of
scaffolds be secured to prevent swaying where necessary, as determined
by a competent person (Tr. 6/9/87, pp. 148-150). One ACCSH member
stated ``I would move that if swaying is prohibited, as discussed in
Question Number 7, that no height limit for suspended scaffolds need be
included.''
Based on the input received, OSHA has determined that suspended
scaffolds which comply with the pertinent requirements of subpart L
will be safe regardless of the height at which they are used.
Therefore, the Agency has not added a height limitation to the final
rule.
Final rule paragraph (d)(19) (proposed Sec. 1926.451(b)(3))
requires that single function emergency escape and rescue devices not
be used as working platforms. This paragraph also provides that the
prohibition does not apply to systems which are designed to function
both as working platforms and as emergency systems.
Proposed paragraph (b)(3) simply prohibited the use of emergency
descent devices as working platforms because such devices are not
normally designed for repeated in-place use. However, as stated in the
preamble to the NPRM (51 FR 42685), the proposed provision was not
intended to preclude the use of scaffold systems which have as an
additional feature the capacity to function as an emergency descent
device.
The proposed provision generated a number of comments (Exs. 2-8, 2-
27, 2-29, 2-87 and 2-312) which recommended that OSHA define
``emergency descent device.'' Most of these commenters interpreted the
regulatory language as prohibiting all emergency descent devices from
being used as work platforms despite the clarification provided in the
preamble. Therefore, OSHA has revised the final rule to indicate
clearly that only devices whose sole function is to provide emergency
escape and rescue are not to be used as working platforms.
Paragraph 1926.451(e) Access
Final rule paragraph (e) sets the requirements for safe access to
scaffolds. This paragraph clarifies the requirements of existing
Sec. 1926.451(a)(13), which requires only that ``an access ladder or
equivalent safe access shall be provided.'' The introductory text
states that employers must provide scaffold access which complies with
paragraph (e) for each affected employee. It also specifies that the
access requirements for employees erecting or dismantling supported
scaffolds are prescribed in paragraph (e)(9).
Proposed paragraph (c) began with a note which stated that the
proposed paragraph did not apply to employees erecting or dismantling
scaffolds. In the preamble to the NPRM (51 FR 42687), OSHA stated that
requirements for safe access ``often are not feasible until a scaffold
has been erected and properly braced.'' OSHA relied on the same
rationale for the proposed exemption of erectors and dismantlers from
the fall protection requirements of proposed paragraph (e).
OSHA received no comments on this proposed exemption directly.
However, many of the comments on Issue 8, which requested input
regarding the need to exempt employees erecting and dismantling
scaffolds from the fall protection requirements of proposed paragraph
(e) (promulgated as paragraph (g) of this final rule) stated that
employees erecting and dismantling scaffolds should not be exempted
from protection. In particular, as discussed below in relation to final
rule paragraph (g), commenters stated that it was often feasible to
provide fall protection for employees erecting or dismantling
scaffolds.
Given the evidence that employers can often protect erectors and
dismantlers from fall hazards, OSHA concluded that it was also
appropriate to consider if there are circumstances where safe access
can be provided for those employees. Accordingly, the Agency reopened
the subpart L rulemaking record to solicit input regarding the proposed
exemption (58 FR 16509, March 29, 1993). In particular, OSHA sought
comments about employers' ability to provide safe access for erectors
and dismantlers, the hazards that could be created by efforts to
provide safe access, and the criteria to be satisfied by employers
seeking to qualify for an exception from the proposed requirements for
safe access.
Three commenters (Exs. 34-8, 34-22, and 34-29) supported an access
requirement for scaffold erectors and dismantlers. One commenter (Ex.
34-8) said that its support depended on adding the words ``or
equivalent means'' to such a requirement. OSHA notes that both proposed
Sec. 1926.451(c)(1) and final rule Sec. 1926.451(e) contain the words
``or equivalent means.'' That commenter also stated that in utility
boiler installations ``ladders and/or stairways are incorporated into
scaffolding. Planking and ladders, where feasible, are used to support
erection or dismantling. New access can be provided by cutting out
sections of the boiler wall, but the cost for it in some areas may be
prohibitive.'' The commenter added that safe access can
[[Page 46051]]
be provided on supported scaffolds 100% of the time in non-boiler
installations.
Another commenter (Ex. 34-22) stated that where safe access cannot
be provided, fall protection can be used. In addition, a commenter (Ex.
34-29) responded that safe access is practically always feasible, and
presented ladders, lifts, and crane personnel baskets as examples. OSHA
agrees that safe access can be provided for erectors and dismantlers in
most instances through the use of various types of equipment, including
(but not limited to) ladders, scaffold stairs, manlifts, and fall
protection equipment. However, the Agency notes that the use of a
ladder or fall protection equipment would require a significant degree
of scaffold stability, which may not be present in an incomplete
scaffold. Additionally, the safe use of stair towers, manlifts or crane
personnel platforms is dependent on site conditions and the
availability of the equipment and additionally requires the employer to
comply with the regulations covering that equipment.
Scaffold Consultants (Ex. 34-5) described a hypothetical situation
involving a scaffold 100 feet long by 50 feet high and planked on all
levels. They raised the following points:
1. How many ladders are to be installed? If there is a ladder in
the middle of the scaffold, certainly an erector will not walk 50
feet to a ladder and then back another 50 feet to relocate.
2. Ladders cannot be installed on the interior of the scaffold
because of the continuous, fully planked decking.
3. If more than one ladder is to be installed, then it would of
necessity be on the outside of the scaffold, forcing the erector to
go outside the scaffold on each succeeding level, exposing the
worker to a fall potential. Traditionally, each ladder section is
installed after that level of scaffold has been completed, and the
worker no longer has need to return to a lower level. You cannot
install a ladder section for the next level up until the scaffold
frames, bracing and planking have been erected.
The code already states (1926.451(a)(13)) that an access ladder
or equivalent safe access shall be provided.
OSHA notes that providing safe access for erectors and dismantlers
does not necessarily mean that all levels of a scaffold must be fully
planked. In addition, the Agency cannot specify the number of ladders
or other means of access that must be provided in all cases, because of
the wide range of situations being addressed by this standard.
Regarding access for employees erecting or dismantling suspended
scaffolds, two commenters (Exs. 34-32 and 34-39) stated that access is
not required because suspended scaffolds are usually erected at ground
level and the rigging is performed at the roof level. Another commenter
(Ex. 34-8) stated that OSHA should consider deleting the proposed
exemption as it relates to suspended scaffolds. OSHA agrees that if a
scaffold is erected at ground level and rigging is performed at the
roof level, employees are deemed to have safe access to and from the
scaffold. However, erection and rigging not performed in this manner
require safe access to be provided, in accordance with final rule
paragraph (e).
Five commenters (Exs. 34-31, 34-32, 34-37, 34-39, and 34-43)
opposed, in general, an access requirement for erectors and
dismantlers. One commenter (Ex. 34-43) stated that the means of access
would have to be removed from a scaffold before dismantling can
proceed. In addition, four commenters (Exs. 34-9, 34-10, 34-12, and 34-
17) stated that, while sectional ladders attached at the ends of the
scaffold can be used for access once adequate support is available,
portable ladders on the work platform may create a greater hazard.
Furthermore, three commenters (Exs. 34-32, 34-37, and 34-39) stated
that providing such access is not practicable on supported scaffolds on
the grounds that not all scaffolds require an attached access and when
one is required ``it is installed after the lift is installed,'' and
``it is not available for the erectors.''
In particular, the SIA (Ex. 34-37) stated that supported scaffold
erectors access the scaffold as the erection/dismantling process
progresses in either direction. Although acknowledging that erectors
also access the scaffold from structures or ladders when convenient,
the SIA added that access systems cannot be installed until the
scaffold is structurally sound, which they stated does not occur in
most cases until the scaffold is complete. OSHA finds, however, that
there are many circumstances where outriggers, braces, ties, guys, and
similar equipment can be used as the erection or dismantling processes
proceed in order to secure, stabilize, or reinforce the lower levels of
the scaffold so that safe access can be provided to these completed
levels.
OSHA realizes that there may be instances where safe access cannot
be provided to the actual level where employees are erecting or
dismantling supported scaffolds. However, the Agency has determined
that it is necessary and appropriate to provide these employees with
safe access to and egress from the levels that have been completed.
Another commenter (Ex. 34-11) wrote that most jobs would not meet
the requirements of proposed Sec. 1926.451(c) without an exemption for
erectors and dismantlers. This commenter called for a study to
determine what procedures are needed to provide safe access. OSHA
finds, however, that the rulemaking record provides the necessary
support for promulgation of access requirements for these employees
and, accordingly, has not adopted this commenter's suggestion. OSHA
intends to monitor the effectiveness and compatibility of final rule
paragraphs (e) and (g) carefully for the next several years, to make
sure they are providing the necessary protection for construction
workers. Based on the results of that monitoring, the Agency will
determine if any further action is warranted.
Several commenters responded to OSHA's request for information
about any hazards that would be created through efforts to comply with
proposed paragraph (c). One commenter (Ex. 34-8) stated ``[i]n utility
boiler installations hazards may outweigh benefits. Employees may
attempt to use a ladder that is not properly secured. Would have to
install more access doors and this is not always feasible. In other
applications of supported scaffold problems are not anticipated.''
Four commenters (Exs. 34-9, 34-10, 34-12 and 34-17) stated:
Use of ladders, etc. to provide access to levels that are in the
process of being dismantled would increase the potential to falls.
This is [due] to the fact that the scaffold would no longer be
stable enough to support the access equipment properly. The levels
of scaffold [that] have been completely erected or not yet
dismantled should retain the permanent access equipment intended to
provide access throughout the length of intended service. The risks
involved during the erection and dismantling process can be lessened
by strict adherence to all procedures.
As discussed above, OSHA has determined that safe access can be
provided to levels that have been completely erected or to levels that
remain intact during dismantling operations.
Three commenters (Exs. 34-32, 34-37 and 34-39) stated ``[t]hese
hazards cannot be eliminated during scaffold erection.'' In addition,
two of the commenters (Exs. 34-32 and 34-39) stated ``[t]he erector
travels both horizontally and vertically and may not be in the vicinity
of an access system when descent is necessary. He may not be able to
get safely to the access area if, for instance, planks have been moved.
Most scaffolds are not fully
[[Page 46052]]
planked and planks are moved as erection progresses.''
On the other hand, two commenters (Exs. 34-11 and 34-29) said that
providing safe access for erectors and dismantlers would not create
hazards.
One commenter (Ex. 34-8) stated that employers should have their
scaffolds evaluated by a competent person and that OSHA should consider
erection and dismantling processes and procedures, accident statistics,
and the type of work to be done on the scaffold before determining in a
given situation that safe access is feasible.
Four commenters (Exs. 34-9, 34-10, 34-12 and 34-17) stated
``[c]ertainly the potential for greater risk should be the greater
consideration. The circumstance that bears the most consideration is
`at what point is the scaffold capable of supporting a ladder or other
access device'. At the point that this occurs permanent access ladders
will be able to be attached to provide access.'' Those commenters also
stated that an employer seeking exemption should be able to demonstrate
that compliance with proposed paragraph (c) would create a greater
hazard, be technologically infeasible, or be economically infeasible.
Three commenters (Exs. 34-32, 34-37, and 34-39) stated that
providing a means of access to a scaffold under construction should not
be required because scaffold erectors are trained to safely climb
scaffolds and because worker access to a completed scaffold may be
directly from the structure itself. The commenters further stated this
would make adding an access system expensive and unnecessary. Those
commenters also contended that a requirement to prove infeasibility
would be expensive and time consuming, and is not supported by accident
data.
In response to comments asserting a lack of accident data to
support imposing burdens on employers whose employees erect or
dismantle scaffolds, NIOSH (Ex. 34-40) stated ``[t]he lack of `accident
statistics' to scaffold erectors is likely to be due to insufficient
detail in injury surveillance data, and not necessarily to a lack of
injuries.'' In addition, NIOSH reviewed the accident data (Ex. 21) and
concluded that ``[t]he fatality rate for scaffold erectors during
scaffold erection and dismantling exceeds that for the entire U.S.
construction industry.'' A review of construction accident reports
shows that 10-20% of scaffold deaths and injuries occur during erection
and dismantling; OSHA finds that many of these will be prevented by the
final rule's fall protection requirements for these operations (see the
Benefits Chapter of the Economics Analysis for this rule).
The Agency notes that the Occupational Safety and Health Review
Commission has held (Hoffman Construction Company, 6 OSHRC 1274,
January 4, 1978) that the safe access requirement of the existing
standard (29 CFR 1926.451(a)(13) does not become operative until the
scaffold is completed or use is imminent, and, therefore, does not
apply to scaffold erection and dismantling operations.
OSHA has determined that although scaffold erectors and dismantlers
are exposed to significant access-related hazards, requiring employers
to provide safe access for erectors and dismantlers in all cases would
often create a greater hazard or be infeasible. For example, commenters
have described factors (e.g., instability of scaffold and lack of
adjacent support) which can preclude the provision of safe access. The
Agency agrees that there are some situations where an exemption from
final rule paragraph (e) would be appropriate. However, other
commenters have indicated that employers who carefully evaluate their
scaffold operations can provide safe access or at least minimize
employee exposure to hazards during these operations. Therefore, OSHA
finds that it is appropriate for employers to be able to obtain relief
from the access requirements when such relief has been determined, on a
case by case basis, to be necessary. Accordingly, the Agency has added
final rule paragraph (e)(9), discussed below, which requires (paragraph
(e)(9)(i)) that employers have a competent person assess pertinent
workplace conditions and decide what means of access is appropriate to
use to protect the safety of erectors and dismantlers on any particular
job.
Final rule paragraph (e)(1) provides that access to and between
scaffold platforms more than two feet (0.6 m) above or below the point
of access shall be by portable ladders, hook-on ladders, attachable
ladders, scaffold stairways, stairway-type ladders (such as ladder
stand), ramps, walkways, integral prefabricated scaffold access, or
equivalent means, or by direct access from another scaffold, structure,
personnel hoist, or similar surface. In addition, the final rule
requires that crossbraces not be used as a means of access. This
provision is identical to proposed paragraph (c)(1), except for some
minor changes in terminology made in order to be consistent with
existing industry terms, and the inclusion of scaffold stairways as
another acceptable means of access. The final rule consolidates and
updates existing Sec. 1926.451(e)(5), which requires that ladders or
stairways be provided and used on mobile scaffolds; existing
Sec. 1926.451(q)(3), which requires that connecting runways with
substantial guardrails be used for access to plasterers', decorators',
and large area scaffolds; and existing Sec. 1926.451(y)(9), which
requires that ladders be used for pumpjack scaffold access.
The SSFI and the SIA (Exs. 2-367 and 2-368) recommended the
inclusion of scaffold stair/towers (scaffold stairways) as a recognized
acceptable means of access. The Agency acknowledges that scaffold
stairways are used regularly for scaffold access and agrees that those
stairways should be addressed by subpart L. Accordingly, OSHA has
incorporated regulatory text addressing scaffold stairways into final
rule paragraph (e)(4), discussed below.
Paragraph (e)(2) of the final rule sets requirements for portable,
hook-on and attachable ladders. A note to this paragraph indicates that
additional requirements for the proper construction and use of portable
ladders are contained in subpart X of this part--Stairways and
Ladders--of the construction standards.
In particular, final rule paragraph (e)(2)(i) provides that
portable, hook-on, and attachable ladders shall be positioned so as not
to tip the scaffold.
In addition, final rule paragraphs (e)(2)(ii)-(vi) provide that
hook-on and attachable ladders shall have bottom rungs positioned not
more than 24 inches (61 cm) above the scaffold supporting level; have
rest platforms at 35 foot (10.7 m) maximum vertical intervals on all
supported scaffolds more than 35 feet (10.7 m) high; be specifically
designed for use with the manufactured type of scaffold to be used;
have a minimum rung length of 11-1/2 inches (29 cm); and have uniformly
spaced rungs with a maximum spacing between rungs of 16-3/4 inches,
respectively. Proposed paragraph (c)(2) was effectively identical,
except that the maximum interval between rest platforms has been
increased in the final rule from 20 feet to 35 feet and the maximum
rung spacing has been increased from 12 inches to 16-3/4 inches, as
discussed below.
Issue 28 in the preamble of the NPRM requested public comment on
whether landing platforms should be required at 35-foot maximum
intervals as required by existing Sec. 1926.451(e)(5), or at 20-foot
maximum intervals as required by proposed Sec. 1926.451(c)(2)(iii).
Three commenters (Exs. 2-13, 2-38, and 2-54) responded in support of
the proposed rule's 20-foot maximum. One commenter (Ex. 2-13) favored
the 20-
[[Page 46053]]
foot interval because it would ``allow a person to catch one's
breath.'' He added that he could personally appreciate this requirement
as he has climbed ladders for years. In addition, a commenter (Ex. 2-
38) stated that ``[l]adders should be offset with landings every 20
feet to prevent falling more that 20 feet.'' Another commenter (Ex. 2-
54) responded that the interval in the proposed rule ``would make it so
workers were not always huffing and puffing and place less strain on
ladders and how many workers might be on it at the same time.''
On the other hand, a commenter (Ex. 2-22) responded that the 35-
foot height was ``an acceptable level for the safety of employees and *
* * a practical field requirement.'' Another commenter (Ex. 2-53)
stated ``[l]anding platforms should be required at 35 foot intervals.
No need to change regulations.'' The SSFI and SIA (Exs. 2-367 and 2-
368) stated that the proposed change to the 20-foot height was too
restrictive and unnecessary. In particular, the SIA (Ex. 2-368) stated
that, since most of the scaffolds which require access from the base
have work platforms less than 28 feet from their base, ``the 20 foot
interval requirement would place a rest platform too close to the work
platform and would be unnecess[a]ry.'' This commenter added that there
are no accident statistics to justify changing the height requirement
from 35 ft. to 20 ft.
The ACCSH (Tr. 191-195, 6-9-87) discussed Issue 28 and recommended
that OSHA adopt the proposed 20-foot requirement. One member stated
``[b]ecause employees are often carrying tools or equipment, the 20-
foot requirement is reasonable.'' OSHA proposed to require landing
platforms at 20-foot maximum intervals in an attempt to be consistent
with existing Secs. 1910.27 (d)(1)(ii), (d)(2) and (d)(5) of the
general industry standards.
After a careful review of the evidence in the record as a whole,
OSHA finds that requiring landing platforms at 20- foot intervals is
not supported by evidence that such a change is needed for employee
safety. In addition, evidence was submitted to show that many scaffolds
already have work platforms only a few feet higher than the 20-foot
level and further that establishing a new height, i.e., 20 feet, would
interfere with widely accepted field practice. Accordingly, the final
rule retains the 35-foot maximum intervals for landing platforms,
because it adequately protects the safety of employees who are
accessing scaffolds.
The SSFI (Ex. 2-367) took ``strong objection'' to proposed
paragraph (c)(2)(vi), which required that there be a maximum spacing
between rungs of 12 inches, because portable, hook-on, and attachable
ladders have been produced for many years with uniformly spaced rungs
that do not meet this requirement. The commenter recommended that OSHA
replace this requirement with a requirement that rungs be uniformly
spaced within each section.
The proposed paragraph was based on existing
Sec. 1910.26(a)(1)(iii), which prescribes maximum rung spacing for
portable metal ladders used in general industry. The Agency notes that
prior to the proposal there were no existing OSHA construction
regulations addressing hook-on or attachable ladders, and the proposal
was intended to recognize that these types of ladders are acceptable
means of access.
OSHA agrees with the commenter that the rungs should be uniformly
spaced to prevent misstepping. In addition, OSHA believes that the
16\3/4\ rung spacing allowed on integral prefabricated scaffold access
frames (end frames) (final rule Sec. 1926.451(e)(6)(v)) should be
applied to hook-on and attachable ladders as well, since these ladders
are commonly used with end frames and this will provide uniform rung
spacing for this application. OSHA has revised the language of the
final rule paragraph (c)(2)(vi) accordingly.
Paragraph (e)(3) of the final rule sets requirements for stairway-
type ladders. In particular, paragraphs (e)(3)(i) through (v) require
that stairway-type ladders be positioned so that the bottom step is not
more than 24 inches (61 cm) above the scaffold supporting level; be
provided with rest platforms at 12 foot (3.7 m) maximum vertical
intervals; have a minimum step width of 16 inches (41 cm) (except for
mobile scaffold stairway-type ladders, which are permitted to have a
minimum step width of 11\1/2\ inches); and have slip-resistant treads
on all steps and landings. These provisions are identical to the
corresponding provisions in proposed paragraph (c)(3), except that an
exception has been added in a new final paragraph (e)(3)(iii) to the
minimum rung width in proposed paragraph (c)(3)(iii). This change has
been made to recognize that a minimum step width of 11\1/2\ inches is
acceptable for mobile scaffold stairway-type ladders, as discussed
below.
Proposed paragraph (c)(3)(iii), which was based on
Sec. 1910.29(a)(3)(ii), required a minimum step width of 16 inches. The
SIA (Ex. 2-368) stated that it is necessary to distinguish between
stairway-type ladders and mobile scaffold stairway-type ladders where
the stairway-type ladder is a secondary feature of the platform. The
commenter noted that reduced step width is necessary on this type of
equipment due to space constraints, and pointed out that the reduced
step width is consistent with normal ladder minimum widths. OSHA
agrees, noting that this type of equipment has been demonstrated to be
safe over decades of use, and has revised the final rule accordingly.
Final rule paragraph (e)(3)(iv) requires slip-resistant treads on
all stairs and landings. This rule is based on general industry rule
Sec. 1910.29(a)(3)(iv), which requires the steps to be fabricated from
slip-resistant treads.
Final rule paragraph (e)(4), which has been added based on the
response to the NPRM and the February 1, 1994 notice of reopening (59
FR 4615), sets requirements for scaffold stairway towers used for
access to scaffolds and other elevated work surfaces. OSHA has
determined that compliance with the provisions described below will
enable employees to use scaffold stairways safely.
The SSFI and the SIA (Exs. 2-367 and 2-368) suggested that OSHA
recognize scaffold stairway/towers as acceptable means of access. They
noted that reference to these types of access units had been omitted
from the proposal even though they are in common use and are a safe
method of obtaining access to scaffold units. Both commenters
recommended that OSHA revise the rule to add requirements for inside
and outside handrails; 19-inch minimum length landing platforms; 19-
inch minimum width for stair units; and slip-resistant surfaces for
treads and landings.
In addition, a commenter (Docket S-041, Ex. 3-414) to the Notice of
Proposed Rulemaking for part 1910 subpart D (Walking and Working
Surfaces) stated:
As in the case of guardrails, the stair rails section is based
on the use of this product in permanently installed locations in
buildings or industrial structures. It does not consider stair rails
used in conjunction with scaffold applications.
Scaffold suppliers utilize step units which have been fabricated
specifically to be used as access to scaffold platforms. These step
units are manufactured with hand rails which are sold as a component
of these step units. The OSHA standard should state that these
fabricated step units are acceptable for scaffold access. This will
eliminate the confusion of the compliance officers in attempting to
enforce permanent stair rail standards for scaffold access
components.
On February 1, 1994, OSHA reopened the subpart L rulemaking record
(59 FR 4615) to solicit comments and suggestions regarding the
regulation of scaffold stairways, chimney bracket scaffolds and tank
builders' scaffolds. In
[[Page 46054]]
particular, the Agency requested input on the provisions suggested by
commenters. In addition, although OSHA did not intend subpart X to
apply to stair towers, the Agency was interested in determining if, in
fact, any of the provisions from part 1926, subpart X or from proposed
part 1910, subpart D, would be appropriate requirements for scaffold
stair towers.
The Agency was interested in receiving more input on the need for
specific regulations for scaffold stairways, chimney bracket scaffolds
and tank builders' scaffolds, with special emphasis on fall protection
requirements, including requirements for handrails and guardrail
systems for the unprotected sides and edges of stairway landings. The
provisions of final paragraph (e)(4) are the product of specific
questions raised in the February 1 notice and OSHA's review of the
responses to those questions.
Two commenters (Exs. 43-24 and 43-32) recommended that the Agency
adopt the suggested provisions, although the first of these two
commenters suggested that existing products that do not comply be
accepted. Several other commenters (Exs. 43-6, 43-11, 43-13, 43-14, 43-
22, 43-26, and 43-37) supported the adoption of various modified
versions of the suggested provisions. For example, suggested minimum
heights above the tread nose for handrails (or stairrails) ranged from
27 inches (68.6 cm) to 36 inches (91 cm).
A number of commenters (e.g., Exs. 43-4, 43-6, 43-9, 43-10)
contended that for many years scaffold stairways have been designed and
used in the same manner as they currently are, and have always provided
a safe and effective means of access. These commenters opposed the
promulgation of any provisions that would alter the criteria under
which scaffold stairways are currently designed and used. Most of these
commenters also reported that they know of no accidents that have
occurred due to the use of scaffold stairways.
In addition, many commenters (Exs. 43-13, 43-14, 43-24, 43-26, 43-
37, and 43-44) specifically opposed applying either the requirements of
subpart X or the general industry standards (Sec. 1910.25 and
Sec. 1910.28) to scaffold stairways. These and other commenters
mentioned above indicated that such an application would, in effect,
``outlaw'' scaffold stairways since they cannot meet the requirements
of subpart X due to the fact that scaffold stairways must be designed
and constructed to fit within the confines of 5 foot (4.5 m) by 7 foot
(6.3 m) or 5 foot (4.5 m) by 10 foot (9.1 m) scaffold bays. As a
result, according to these commenters, many employers would simply stop
using most scaffold stairways, and would rely instead on other means of
access that are not as safe as scaffold stairways. However, one
commenter (Ex. 43-8) recommended that scaffold stairways covered by
subpart L be consistent with subpart X and the general industry
standards. Another commenter (Ex. 42-33) supported standardizing the
existing stairway standard's requirements, including hand clearances,
end rail projections, type of surface, and guarding of the open sides
of landings.
Scaffold stairways can provide a safe and effective means of
access, and the Agency has no intention of prohibiting the use of all
existing scaffold stairways. However, the Agency does believe that some
provisions governing the construction and use of scaffold stairways
must be included in final subpart L, and that the provisions should be
as consistent as possible with subpart X and the general industry
standards, in order to ensure the safety of the employees who use
scaffold stairways. Accordingly, OSHA has promulgated the provisions
discussed below.
The introductory language of final rule paragraph (e)(4) requires
that these units be positioned so that the bottom step is not more than
24 inches (61 cm.) above the scaffold supporting level.
Final rule paragraph (e)(4)(i) requires that a stairrail consisting
of a toprail and a midrail be provided on each side of each scaffold
stairway. Furthermore, final paragraph (e)(4)(ii) requires that the
toprail of each stairrail system shall be capable of serving as a
handrail, unless a separate handrail is provided.
Six commenters (Exs. 43-6, 43-11, 43-14, 43-26, 43-37, and 43-44)
indicated that inside and outside handrails should incorporate
midrails. Several commenters (Exs. 43-8, 43-13, 43-14, 43-24, 43-26,
and 43-37) stated that scaffold stairways should incorporate handrails,
stairrails and midrails. One commenter (Ex. 43-45) stated that scaffold
stairways should have stairrail systems with midrails. Another
commenter (Ex. 43-22) stated that inside and outside handrails should
be constructed so that they function as both stairrails and handrails.
OSHA agrees that handrails, stairrails, and midrails are necessary
for adequate employee protection. However, the Agency also believes
that adequate protection can be provided when toprails of stairrail
systems are capable of serving as adequate handrails. Paragraph
(e)(4)(ii) of the final rule recognizes the capability of toprails to
serve as handrails, but also requires that a separate handrail be
provided when toprails are not capable of serving as a handrail.
Final rule paragraph (e)(4)(iii) requires that handrails, and
toprails that serve as handrails, provide a handhold for employees
grasping them to avoid falling. This provision is identical to
Sec. 1926.1052(c)(9), except for the explicit inclusion of toprails.
Monsanto (Ex. 43-45) stated that handrails should have the shape and
dimension necessary to provide a firm handhold, but provided no
specific shapes or dimensions that would meet that suggested
requirement. OSHA agrees that handrails must be shaped and sized in
such a manner that a proper handhold is provided.
Final rule paragraph (e)(4)(iv) requires that stairrail systems and
handrails be surfaced in a manner that prevents injury to employees
from punctures or lacerations, and to prevent snagging of clothing.
This provision is essentially the same as Sec. 1926.1052(c)(8).
Monsanto (Ex. 43-45) suggested that stairrail systems ``be free of
projection and/or puncture/abrasion hazards.'' OSHA agrees that
handrails should not present such hazards, and the final rule's
language reflects this concern.
Final rule paragraph (e)(4)(v) requires that the ends of stairrail
systems and handrails be constructed in a manner that does not
constitute a projection hazard. This provision is essentially identical
to Sec. 1926.1052(c)(10).
Final rule paragraph (e)(4)(vi) requires that scaffold stairway
handrails, and toprails that are used as handrails, have a minimum
clearance of 3 inches (7.6 cm) between the handrail or toprail and
other objects. This provision is essentially the same as
Sec. 1926.1052(c)(11). As mentioned above, one commenter (Ex. 42-33)
stated that hand clearances for scaffold stairways should be the same
as those for stairways covered by subpart X. OSHA agrees with this
commenter and notes that inadequate hand clearances can render
handrails essentially useless.
Final rule paragraph (e)(4)(vii) requires that stairrails be no
less than 28 inches (71 cm) or more than 37 inches (94 cm) from the
upper surface of the stairrail to the surface of the tread, in line
with the face of the riser at the forward edge of the tread. This
provision differs from the stairrail height requirements of subpart X,
which was never intended to apply to scaffold stairways. Paragraph
(e)(4)(vii) of the final rule is based on the following comments.
One commenter (Ex. 43-11) suggested stairrail height ranging from
27 inches (68.6 cm) to 37 inches (94 cm) vertically
[[Page 46055]]
above the nose of each step. Another commenter (Ex. 43-20) recommended
a range of 22 inches (56 cm) to 41 inches (104 cm). One other commenter
(Ex. 43-45) recommended stairrail systems ``no less than 36 inches (91
cm) high.'' However, several other commenters (Exs. 43-6, 43-13, 43-14,
43-26, and 43-37) recommended that stairrails be no less than 28 inches
(71 cm) and no more than 37 inches (94 cm) above the nose of each step.
OSHA notes that Sec. 1926.1052(c)(3) requires that stairrail
systems installed before March 15, 1991, be no less than 30 inches
(76.2 cm) high, and that those installed after March 15, 1991, be no
less than 36 inches (91.4 cm) high. The Agency recognizes that this
subpart X requirement may not have been appropriate for stairrails on
some scaffold stairtowers, because the construction of stairtowers
differs significantly from that of stairtowers addressed by subpart X.
In particular, stairtowers are fashioned from scaffold components, must
fit within the framing of scaffold units, and rise more steeply than
other stairways. As a practical matter, the steeper the stairway, the
closer the stairrail will be to the stair surface. Therefore, OSHA has
concluded that it is appropriate and adequately protective for
stairtower stairrails to be at least 28 inches, rather than 30 inches,
high. Accordingly, a requirement that employers retrofit scaffold
stairtowers with 30-inch high stairrails, or that employers phase in
30-inch high stairrails at some future time, would be unreasonable.
OSHA believes that existing equipment and designs can comply with the
28-inch height requirement and should continue to be allowed in use. In
addition, OSHA observes that stairtowers with 28-inch high stairrails
are safer than ladders and that requirements to retrofit or redesign
stairtowers could lead cost-averse employers to use ladders instead of
stairtowers.
Final rule paragraph (e)(4)(viii) requires that scaffold stairways
be provided with landing platforms that are at least 18 inches wide and
at least 18 inches (45.7 cm) long at each level. This provision
provides adequate protection for employees without impeding the use of
most scaffold stairways now in use.
Several commenters (Exs. 43-6, 43-13, 43-20, 43-22, 43-24, and 43-
33) who addressed the issue of landing platforms supported requiring
landing platforms at least 19 inches (48.3 cm) wide at every level.
Three other commenters (Exs. 43-14, 43-26, and 43-37) recommended that
landing platforms at least 18 inches (45.7 cm) wide be required at each
level. Four of those commenters (Exs. 43-6, 43-14, 43-26, and 43-37)
also suggested adding to such a provision the alternative of providing
a platform at least 30 inches long (76.2 cm) in the direction of travel
at ``every 14 feet (4.5 m) maximum of stair elevation.'' Those
commenters stated that this would ``allow the continued use of frame
scaffolds spaced 6\1/2\ feet (2.1 m) vertically and system scaffolds
which are based upon 7 foot (2.25 m) maximum vertical bearer spacing.''
In addition, two commenters (Exs. 43-11 and 43-45) recommended a
minimum landing width of 24 inches (61 cm). Another commenter (Ex. 43-
22) recommended that ``landing platforms extend the entire width of the
scaffold instead of only one-half the width as they do now.''
OSHA believes that employee safety mandates that a landing meeting
the requirements and specifications of this provision must be provided
on stairtowers. The Agency also believes that landings must be as wide
as the stairway itself (at least 18 inches (45.8 cm)) in the direction
in which the stairway is measured and at least 18 inches long in the
other direction as well.
Final rule paragraph (e)(4)(ix) requires that each scaffold
stairway be at least 18 inches (45.8 cm) wide between stairrails.
Several commenters (Exs. 43-6, 43-8, 43-11, 43-13, 43-14, 43-20, 43-22,
43-24, 43-26, 43-32, and 43-37) supported a minimum stair width of 19
inches (48.2 cm). However, the record provides no basis for OSHA to
require that stairs be wider than their landings. In addition, 18
inches is the minimum width allowed for normal scaffolds.
Final rule paragraph (e)(4)(x) requires that treads and landings
have slip-resistant surfaces. This provision is consistent with
existing Sec. 1926.1052(a)(7), which requires that slippery conditions
on stairways be eliminated before the stairways are used to reach other
levels.
Several commenters (Exs. 43-6, 43-8, 43-11, 43-13, 43-14, 43-20,
43-22, 43-24, 43-26, 43-32, 43-37, and 43-44) supported a requirement
that treads and landings have slip-resistant surfaces. The Agency
agrees with those commenters, and notes that scaffolds are often used
in conditions that can create slippery surfaces.
Final rule paragraph (e)(4)(xi) requires that scaffold stairways be
installed between 40 degrees and 60 degrees from the horizontal.
Existing Sec. 1926.1052(a)(2) requires that stairs be installed at
between 30 degrees and 50 degrees from horizontal. OSHA believes that a
minimum and a maximum angle must be specified in order to adequately
protect employees from fall hazards. However, the Agency believes that
compliance with existing Sec. 1926.1052(a)(2) will not be feasible for
stairways regulated under subpart L, because scaffold stairways must
fit into the confines of scaffold framing.
Six commenters (Exs. 43-6, 43-13, 43-14, 43-24, 43-37, and 43-44)
opposed the specification of a minimum and a maximum angle from the
horizontal for scaffold stairways. However, five of these commenters
(Exs. 43-6, 43-13, 43-14, 43-37, and 43-44) provided suggested values
in case OSHA should decide to specify a minimum and a maximum angle
anyway. Four (Exs. 43-6, 43-13, 43-14, and 43-37) of those commenters
suggested a minimum angle of 40 degrees and a maximum angle of 55
degrees since the stairs must fit into 7-foot (2.25 m) or 10-foot (3.2
m) bays with landing platforms. The fifth commenter (Ex. 43-44)
recommended angles of 35 degrees and 55 degrees. Three (Exs. 43-6, 43-
14, and 43-37) of those commenters stated that once the angle
approaches 80 degrees, the stairway becomes a ship's ladder. Another
commenter (Ex. 43-11) agreed with that concept but placed the angle at
60 degrees.
One commenter (Ex. 43-11) recommended that the limits be set at 40
degrees and 80 degrees, while another commenter (Ex. 43-22) recommended
a maximum angle of 50 degrees but provided no minimum value. Another
commenter (Ex. 43-32) recommended a minimum angle of 30 degrees and a
maximum angle of 50 degrees in order to make subpart L consistent with
subpart X.
OSHA has determined that scaffold stairways installed in the range
of 40 degrees to 60 degrees from the horizontal will provide safe
employee access and will still be capable of fitting into the confines
of the scaffold frames. Paragraph (e)(4)(xi) of the final rule reflects
this determination.
Final rule paragraph (e)(4)(xii) requires that guardrails meeting
the requirements of 1926.451(g)(4) be provided on the open sides and
ends of each landing.
OSHA asked in the February 1, 1994 reopening notice if guardrails
installed on scaffold stairways should comply with both subpart M (fall
protection) and this subpart L.
One commenter (Ex. 43-8) recommended that such guardrails meet the
requirements of subpart M for the sake of consistency. Another
commenter (Ex. 43-13) suggested that only the
[[Page 46056]]
provisions of subpart L should apply. Two other commenters (Exs. 43-14
and 43-37) opposed any requirement for guardrails on landing platforms,
unless work was to be performed from them, on the grounds that ``(n)o
hazard or accident data supports this requirement.''
OSHA believes that employees on landing platforms must be
adequately protected from fall hazards while on a landing whether they
are working from the landing or not. However, the Agency recognizes
that providing guardrails that meet the requirements of subpart M would
be inappropriate for use on scaffolds and scaffold stair towers because
they are built to other requirements. Instead, OSHA has determined that
scaffold guardrails, as required in subpart L, are appropriate because
employers build scaffold stairways using scaffold components, which are
designed for 36 to 45-inch high guardrails. In addition, the Agency
notes that scaffold stairways have been in use for many years and that
guardrail systems that comply with subpart L have provided adequate
safety for employees using these stairways. Accordingly, final rule
paragraph (a)(4)(xii) requires guardrails between 36 and 45 inches in
height be used on the open sides and ends of each landing.
Final paragraph (e)(4)(xiii) requires riser heights within each
flight of scaffold stairs to be uniform within \1/4\ inch.
Four commenters (Exs. 43-8, 43-32, 43-44, and 43-45) recommended
that OSHA require uniform riser height for all steps within each flight
of stairs. Six commenters (Exs. 43-6, 43-11, 43-13, 43-14, 43-24, and
43-37) responded that a uniform riser height within \1/4\ inch (0.6 cm)
is possible to achieve, except for the first step and the last step
where variations in decking thickness and the use of screw jacks at
ground level make achieving this degree of uniformity difficult. OSHA
believes that a uniform riser height within \1/4\ inch (0.6 cm) for all
steps in each flight of stairs is necessary in order to minimize the
possibility that employees will slip, trip, and fall while they are on
the stairs.
OSHA recognizes that there are situations where the level of the
ground or of the structure to which the stair tower is connected will
cause the spacing of the top or bottom step of the stairway system to
deviate from uniformity with the other steps by more than \1/4\ inch.
The Agency has determined that such deviation will not compromise
employee safety, so long as the stair tower otherwise complies with the
requirements of paragraph (e)(4).
Final paragraph (e)(4)(xiv) requires that tread depth be uniform,
within \1/4\ inch, for each flight of stairs. This provision is
consistent with existing Sec. 1926.1052(a)(3), which requires tread
depth uniformity in other types of stairs used in construction.
Monsanto (Ex. 43-45) supported requirements providing for
uniformity of riser height and tread depth within each flight of
stairs. OSHA believes that tread depth uniformity, within \1/4\ inch,
as required in existing subpart X, is also appropriate for scaffold
stairways. Uniform tread depth reduces the possibility that employees
will slip and fall due to uneven footing.
Final rule paragraph (e)(5) sets requirements for ramps and
walkways used to access scaffolds. Final rule paragraph (e)(5)(i)
provides that ramps and walkways six (6) feet (1.8 m) or more above
lower levels shall be provided with guardrail systems in accordance
with the provisions of part 1926, subpart M--Fall Protection. In
addition, final rule paragraph (e)(5)(ii) provides that ramps and
walkways shall not exceed a slope of one (1) vertical to three (3)
horizontal (20 degrees above the horizontal). Finally, final rule
paragraph (e)(5)(iii) also requires that if the slope of a ramp or
walkway is steeper than one (1) vertical in eight (8) horizontal, the
ramp or walkway must have cleats not more than fourteen (14) inches (35
cm) apart which are securely fastened to the planking to provide secure
footing.
The corresponding proposed paragraph simply required that ramps and
runways be provided with guardrails in accordance with the provisions
of proposed Secs. 1926.501 and 1926.502 (Subpart M). As discussed above
in relation to the final rule term ``ramps'', OSHA has replaced the
term ``runways'' with the term ``walkways'', since the term
``walkway'', unlike the term ``runways'', is defined in this final
rule.
A commenter (Exs. 2-37 and 2-103) stated ``[r]amps and walkways are
used extensively * * * as a means of egress to an elevated surface.
Ramps are also used for material handling equipment. Since no standard
angle of elevation is addressed, an extreme angle of elevation and
slippery surfaces would result in fall-type accidents and muscle
strains.'' The commenter also stated that inadequately guarded walkways
pose fall hazards. The commenter recommended language that would
address the angle of elevation of ramps and would require cleats on
ramps with slopes steeper than one (1) vertical in eight (8) horizontal
to provide a safe foothold.
OSHA recognizes the need to indicate clearly what would be an
appropriate slope for ramps used as access to scaffolds and has
incorporated this language into the final rule as paragraphs
1926.451(e)(5)(ii) and (iii).
The Agency notes that final rule Sec. 1926.451(f)(8) requires that
employees be prohibited from working on scaffolds covered with snow,
ice, or other slippery material except as necessary for removal of such
material. OSHA considers scaffold access ramps and walkways to be part
of the scaffold and will also apply Sec. 1926.451(f)(8) to those ramps
and walkways.
Final rule paragraph (e)(6) sets requirements for integral
prefabricated scaffold access frames. Final rule paragraph (e)(6)(i)
provides that such frames shall be specifically designed and
constructed for use as ladder rungs. Also, final rule paragraph
(e)(6)(ii) requires that the frames have a rung length of at least 8
inches (20 cm). Final rule paragraph (e)(6)(iii) prescribes that rungs
less than 11\1/2\ inches in length shall be used for access only and
not as work platforms unless fall protection, or a positioning device,
is used. In addition, final rule paragraphs (e)(6)(iv) through (vi)
require that integral prefabricated scaffold access frames be uniformly
spaced within each frame section; provided with rest platforms at 35
foot (10.7 m) maximum vertical intervals on all supported scaffolds
more than 35 feet (10.7 m) high; and have a maximum spacing between
rungs of 16\3/4\ inches (43 cm), respectively. In addition, final rule
paragraph (e)(6)(vi) provides that non-uniform rung spacing caused by
joining end frames together is allowed, provided the resulting spacing
does not exceed 16\3/4\ inches (43 cm). These provisions are similar to
those in proposed paragraph (c)(5).
Regarding the proposed introductory text, the SSFI (Ex. 2-367)
recommended using the words ``access frames'' instead of the word
``rung.'' OSHA agrees that the suggested language more clearly states
the Agency's regulatory intent and has revised this paragraph in the
final rule accordingly.
Paragraph (e)(6)(i) of the final rule is identical to proposed
paragraph (c)(5)(i) except that the Agency has editorially revised the
provision to express OSHA's intent more clearly. OSHA recognizes that
the proposed language could have been misinterpreted to require only
that the access frames be designed as scaffold rungs, with no
requirement for them to be constructed in accordance with that design.
OSHA anticipates that these rungs will be designed and constructed
through consultation between the manufacturer and the end
[[Page 46057]]
user in order to satisfy the pertinent requirements of the final rule.
Final rule paragraph (e)(6)(ii) requires a minimum rung length of
eight inches. In addition, final rule paragraph (e)(6)(iii) prohibits
the use of rungs less than 11\1/2\ inches long as work platforms,
unless affected employees are using personal fall arrest systems or
positioning devices that comply with Sec. 1926.502 (paragraphs (d) and
(e), respectively). These two provisions evolved from proposed
(c)(5)(ii), which required a minimum rung length of 11\1/2\ inches (29
cm). Morgen Manufacturing Company (Ex. 2-303) commented that scaffolds
with integral prefabricated scaffold rungs which are only eight inches
long also ``provide safe access [to a work platform] equivalent to that
of a ladder.'' Further, the commenter stated that the 8-inch rungs
``provide surer footing and a better climb than does or can a ladder.''
Another commenter (Ex. 2-23) stated that all ladders should have a
minimum rung length of 12 inches in order to avoid confusion.
To evaluate this point, Issue L-6 of the hearing notice asked if
OSHA should revise proposed Sec. 1926.451(c)(5)(ii) to allow rung
lengths less than 11\1/2\ inches where the rungs were used for access
only. The SIA (Ex. 10; Tr. 3/22/88, p. 159) supported the 11\1/2\-inch
width requirement explaining ``[i]t's our understanding that the 11\1/
2\-inch width was required * * * to allow the workman to stand on a
rung with both feet * * * [A]n 8-inch rung would not be wide enough.''
Similarly, the SSFI (Ex. 5a-19) commented that its members would not
support reducing ``the minimum rung width from 11\1/2\ inches to * * *
eight inches.'' They added that practical usage indicates that 11\1/2\-
inch ladder rungs are appropriate.
Bristol Steel and Iron Works, Inc. (Ex. 13) stated that scaffold
rungs that were less than 11\1/2\ inches long were acceptable ``if they
provide safe access equivalent to that of a ladder.''
Morgen Scaffold's notice of intention to appear at the hearing (Ex.
5a-10), testimony at the hearing (Tr. 20-32, 3-22-88), and post-hearing
comments (Ex. 15), stated that OSHA should either revise the proposed
rule as provided in Issue L-6 or grandfather the existing Morgen
scaffolds to permit continued use of the 8-inch integral rung system.
Morgen contended (Ex. 5a-10, p. 2) that its scaffold tower's
integral rungs provide a safe and stable footing and handhold for
workers using the towers for access to connection points for
installation and removal of bracing and accessories. Morgen's post-
hearing comments (Ex. 15, p. 3) further contended that the Morgen
integral-rung system was safer than those requiring the use of a ladder
and offered the following rationale:
Morgen feels that the tower provides a more secure area from
which to install and remove the bracing and accessories than would a
ladder. When using a ladder with any type of scaffolding, the worker
is generally further from the connection point and must shift his
weight off the ladder to install bracing.
At the hearings, Morgen acknowledged that at no time are workers
able to put both feet on the same eight-inch rung (Tr. 3/22/88, p. 25).
However, Morgen also stated that ``the size of the Morgen tower allows
the worker to hug the tower, which is more secure than merely standing
with both feet on one rung'' (Ex. 15, p. 3). Morgen also asserted that
worker activities, rather than an arbitrary dimension, should be the
main consideration (Ex. 15, p. 7). OSHA believes that the 11\1/2\-inch
dimension is not an ``arbitrary dimension'', because this rung size is
generally recognized as necessary to provide workers with level footing
of sufficient size to enable them to stand on both feet, thus avoiding
the need to balance on one foot.
Morgen recognized (Tr. 28) that it is appropriate for employees to
use personal fall arrest or positioning devices while transporting or
installing scaffold components. Morgen recommends that personal fall
arrest systems be used to protect employees when tower inserts are
being added ``because the worker must keep both hands free to guide the
inserts into position'' (Ex. 15, p. 6). These same systems can be
easily used during other scaffold erection and disassembly procedures.
Morgen also stated (Ex. 15, p. 8) as follows:
Morgen has no objection to the institution of an industry wide
requirement for the use of body belts while installing bracing,
stiff arms, accessories and planking from integral ladder rungs.
Morgen's objection to the language currently proposed is that it
singles out Morgen and implies that the Morgen design is not safe.
Morgen objects to that characterization and feels that its scaffold
is among the safest in the industry. The characteristics which OSHA
wants to address, concerning the safe installation of scaffold
elements while in the air, are not unique to the Morgen scaffold and
do not depend upon a specified rung length.
OSHA agrees that the concerns addressed are not unique to Morgen
scaffolds. However, OSHA disagrees with the position that there is no
practical difference between an eight-inch rung where an employee can
stand only on one foot and must hug the tower to maintain balance and
an 11\1/2\-inch rung where both feet may be placed on a single rung.
OSHA also notes that Sec. 1926.1053(a)(4)(ii) specifies 11\1/2\ inches
as the appropriate minimum rung length on portable ladders.
After a careful evaluation of all the comments received, OSHA has
determined that rungs which are at least 8 inches long but less than
11\1/2\ inches long can be used safely for scaffold access, because
while climbing or descending the employee will normally have only one
foot on a rung at any given time and the 8 inch rungs will accommodate
this. However, employees who are assigned to use such rungs as work
platforms must be provided additional protection by the use of personal
fall arrest systems, or by positioning device systems, which comply
with Sec. 1926.502. This additional safeguard will ensure that
employees required to work from rungs less than 11\1/2\ inches in width
will be adequately protected from falling. This provision of the final
rule has been revised accordingly.
Final rule paragraph (e)(6)(iv) is identical to proposed paragraph
(c)(5)(iii), except that the term ``frame'' has been revised in the
final rule to read ``each frame section,'' so that the provision
clearly addresses situations where end frames are joined together,
producing non-uniform spacing in the area where the frames are joined.
OSHA was concerned that the proposal could have been misinterpreted to
require absolutely uniform spacing for the entire height of the
scaffold. That was not OSHA's intent, as evidenced by proposed
(c)(5)(v) (final rule paragraph (e)(6)(vi)) which prescribed maximum
spacing of rungs, but allowed for non-uniform spacing caused by the
joining of end frames.
Proposed paragraph (c)(5)(iv) differed from final rule paragraph
(e)(6)(v) in that the proposal required rest platforms at 20-foot
intervals instead of 35-foot intervals. This revision is based on the
response to Issue 28, as discussed above in relation to final rule
paragraph (e)(2)(iii).
Proposed paragraph (c)(5)(v) differed from final rule paragraph
(e)(6)(vi) in that the proposal required 16\1/2\-inch instead of 16\3/
4\-inch maximum spacing of rungs. This change reflects input from the
SSFI (Ex. 2-367), which informed OSHA that 16\3/4\ inches is the
current industry guideline for rung spacing. In proposing 16\1/2\
inches OSHA intended to recognize the large number of frames already in
existence without requiring a significant program of frame
modification. Therefore, based on the
[[Page 46058]]
comment indicating that 16\3/4\ inches, not 16\1/2\ inches, is the
prevalent spacing, and because the additional one-fourth-inch spacing
is not believed to be significant, OSHA has modified the final rule to
recognize the 16\3/4\ inch spacing limit.
Final rule paragraph (e)(7) provides that all steps and rungs of
all ladder and stairway type access shall line up vertically with each
other between rest platforms. Proposed paragraph (c)(6) was identical
except that the final rule has added the phrase ``of all ladder and
stairway type access'' so that the final rule more clearly expresses
the Agency's intent.
Final rule paragraph (e)(8) provides that direct access to or from
another surface shall be allowed only when the pertinent surfaces are
not more than 14 inches (36 cm) apart horizontally and not more than 24
inches (61 cm) apart vertically. It is identical to proposed paragraph
(c)(7) except for the addition of the phrase ``to or from another
surface'' and some other minor editorial changes. The 14-inch dimension
was chosen to be consistent with proposed Sec. 1926.451(b)(4)
(promulgated as final rule Sec. 1926.451(b)(3)).
The 24-inch dimension is consistent with final rule paragraphs
(e)(1), (e)(2)(ii) and (e)(3)(i), as discussed above.
Paragraph (e)(9) of the final rule sets access requirements for
employees erecting or dismantling supported scaffolds. The introductory
language of paragraph (e)(9) requires employers to comply with final
paragraphs (e)(9)(i)-(iv) starting on September 2, 1997. OSHA has
delayed implementation of this paragraph (as well as paragraph (g)(2))
so that affected employers have sufficient time to develop and
implement the necessary measures. In addition, the delayed
implementation allows time for OSHA to complete work on non-mandatory
Appendix B, discussed below, which will provide examples of
considerations that employers complying with paragraphs (e)(9) and
(g)(2) would take into account. Paragraph (e)(9)(i) provides that the
means of access for erectors or dismantlers shall be determined by a
competent person, based on specific site conditions and the type of
scaffold being erected. As discussed in relation to the introductory
text of final rule paragraph (e), while the Agency originally proposed
to exempt erectors and dismantlers working on supported scaffolds from
requirements for safe access, careful review of the record has led OSHA
to the conclusion that a competent person is the appropriate individual
to decide what the appropriate means of access for scaffold erectors
and dismantlers is on any particular job, based on specific site
conditions.
As discussed below in relation to final rule Sec. 1926.451(f)(7)
(effectively identical to existing rule Sec. 1926.451(a)(3) and
proposed rule paragraph (d)(7)), employers are required to have the
erection, dismantling or alteration of a scaffold conducted under the
supervision and direction of a competent person who is qualified in the
pertinent subject matter.
OSHA is developing non-mandatory Appendix B, which will be added at
a later date, to provide examples of criteria for the competent person
to consider when evaluating the feasibility and safety of the options
for providing safe access. This final rule reserves Appendix B to
enable OSHA to provide guidance on the feasibility of providing safe
access and fall protection during erection and dismantling. Once that
language has been added, access provided in accordance with non-
mandatory Appendix B will be considered to meet the requirements of
this provision.
Paragraph (e)(9)(ii) of the final rule requires that hook-on or
attachable ladders be installed as soon as practical after the scaffold
erection has progressed to the point permitting their installation and
use. OSHA has included this provision because the rulemaking record
(Exs. 34-9, 34-10, 34-12, and 34-17) indicates that sectional ladders
can be used for access once adequate support is available.
Paragraph (e)(9)(iii) of the final rule recognizes that the end
frames of tubular welded frame scaffolds that meet certain requirements
can be safely used as a means of access for scaffold erectors and
dismantlers. These requirements are based on section 1637(n)(2)(C) of
the California code, as suggested by one of the commenters (Ex. 2-23).
Paragraph (e)(9)(iv) of the final rule provides that crossbracing
is not an acceptable means of access on tubular welded frame scaffolds,
because crossbraces are designed to provide diagonal stability to the
scaffold and are not designed to withstand the forces that could be
applied by employees climbing up and down on them. This provision is
consistent with ANSI A10.8, section 4.18, and with the general
prohibition in final rule paragraph (e)(1), discussed above. This
requirement is being repeated here to ensure that the users are aware
that the prohibition applies to scaffold erectors and dismantlers as
well as to scaffold users. The Agency invites interested parties to
provide OSHA with suggestions and information regarding appropriate
guidance for the competent person.
Paragraph Sec. 1926.451(f) Use
Paragraph (f) of the final rule addresses safe work practices for
the use of scaffolds and the activities which take place on scaffolds.
Paragraph (f)(1) of the final rule provides that scaffolds and
scaffold components shall not be loaded in excess of their maximum
intended loads or rated capacities, whichever is less. This is
identical to proposed paragraph (d)(1), except for the clarifying
phrase ``whichever is less.'' This provision clarifies and consolidates
existing Secs. 1926.451(h)(1), (i)(8), (j)(1), (s)(6), (t)(4), (w)(1),
(x)(3) and (y)(1)(iii). This final rule also complements
Sec. 1926.451(a)(1), which requires that scaffolds be capable of
supporting four times the maximum intended load without failure.
Compliance with this rule ensures that the scaffold's capacity is not
exceeded.
A commenter (Ex. 2-64) suggested deleting the term ``maximum
intended load.'' OSHA has not done so because, as discussed above in
relation to the definition of this term, the Agency believes it is
appropriate to take into account the ``expected'' burden as well as the
burden a scaffold ``can'' support without failure.
Paragraph (f)(2) of the final rule prohibits the use of shore or
lean-to scaffolds. The final rule is identical to proposed paragraph
(d)(2), which was based on existing Sec. 1926.451(a)(20). Such
scaffolds are not properly designed nor properly constructed, and pose
a serious threat to anyone working on them. The two commenters (Exs. 2-
23 and 2-308) who addressed this provision simply agreed with the
continued prohibition of shore and lean-to scaffolds.
Paragraph (f)(3) of the final rule requires that scaffolds and
scaffold components be inspected for visible defects by a competent
person prior to each work shift and after any occurrence which could
affect a scaffold's structural integrity. Final rule paragraph (f)(3)
is identical to proposed paragraph (d)(3), which was based on existing
Secs. 1926.45(i)(7) and (k)(5). Those existing provisions require
inspections of certain types of suspension scaffolds. Given the
importance of detecting defects in scaffolds and scaffold components,
OSHA concludes that all scaffolds need to be inspected at the times
specified in the final rule.
Issue 16 requested comment on the proposed frequency of scaffold
[[Page 46059]]
inspections for visible defects ``prior to each workshift.'' Two
commenters (Exs. 2-13 and 2-69) stated that only certain types of
scaffolds can be fully or partially inspected prior to each workshift.
Those commenters agreed that two-point suspension scaffolds can be
fully inspected, but they indicated that such an inspection could not
be done for ``tubular welded frame scaffold covering a multi-story
building.'' One of them (Ex. 2-13) added that proposed
Sec. 1926.451(d)(3) should specify the types of scaffolds to be
completely inspected prior to each workshift and offered suspension and
small supported scaffolds as examples. The other (Ex. 2-69) stated that
inspecting a multi-story scaffold system could take the majority of the
work shift.
OSHA acknowledges that the amount of time needed to perform visual
inspection may depend on the type and size of the scaffold being
inspected. However, OSHA believes that it is appropriate for the
proposed inspection requirement to cover all types of scaffolds,
because any scaffold (or scaffold component) can have or develop
defects which would pose hazards for employees if allowed to remain in
service without being inspected. In addition, OSHA believes that the
time to conduct a careful inspection for ``visible defects'' will
involve a reasonable amount of time when considered in relation to the
scale of the work in question.
Another commenter (Ex. 2-64) stated that suspended scaffolds (``and
associated equipment'') should be inspected according to the
manufacturer's recommendations. In addition, this commenter provided a
copy of the company's recommended inspection schedule for particular
suspension scaffold components. This commenter also stated that
``improper maintenance was the most frequent cause of product
incidents.''
One commenter (Ex. 2-43) stated that the ``[i]nspection procedures
for swing stages are adequate'' but that ``[w]eekly or monthly
inspections on rolling or stationary scaffolds should be mandated.''
Another commenter (Ex. 2-31) responded that the daily inspections
(prior to each workshift) were ``appropriate for the pumpjack
scaffolding user.''
Eight commenters (Exs. 2-15, 2-22, 2-53, 2-70, 2-367, 2-368, 2-407,
and 2-465) supported specifying scaffold inspection frequency, without
regard to the type or size scaffold inspected. In particular, a
commenter (Ex. 2-22) stated that the inspection frequency should be no
more ``than once per day or after an occurrence.'' Another commenter
(Ex. 2-53) was of the opinion that scaffolds and scaffold components
should be inspected for visible defects prior to each use. The ACCSH
recommended that scaffold inspection should take place prior to use,
and added that a competent person should handle the inspection (Tr.
6/9/87, 136-138).
The SIA (Ex. 2-368) also supported having a competent person
perform the inspection but stated that a full inspection was not
``feasible every time a worker gets on a scaffold.'' The commenter
stated that ``[i]nspection is a critical factor in accident
prevention'' and agreed that the daily inspection, prior to each
workshift, was appropriate. The SIA also discussed specific occurrences
that might alter the condition of a scaffold, explaining that these
``would include unexplained shifting, movement, or malfunction of
equipment where [the] scaffold is a mechanical device.''
In addition, the SSFI (Ex. 2-367) indicated that the recommendation
for daily inspection coincided with the proposed ANSI A10.8
requirements for inspection. They added that a scaffold should be
inspected when it ``has been altered, either by accident or design.''
The BCMALU (Ex. 2-54) supported the inspection of scaffolds and
their components but did not indicate a preferred interval for such
inspections.
After a careful review of these comments, OSHA has determined that
inspections conducted by a competent person before each shift and after
any occurrence that would affect the scaffold's integrity will
adequately protect employees working on scaffolds and ensure that
defects are detected in a timely fashion. Given the variety of
scaffolds and situations that arise regarding their use, the Agency
believes that specifying the inspection frequency would unnecessarily
limit employers' flexibility.
One commenter (Ex. 2-308) stated that all inspection results should
be in writing and be signed by a ``competent person.'' This commenter
pointed out that the duration of a ``workshift'' needed to be defined
if inspection was required before each shift. OSHA believes that such
documentation is unnecessarily burdensome, especially in light of
Sec. 1926.451(f)(4) of this final rule, which requires immediate
repair, replacement, bracing, or removal from service of any scaffold
part that does not meet the strength requirements of Sec. 1926.451 (a)
or (g). In addition, the Agency recognizes that the length of
workshifts varies and has determined that the protection afforded by
this provision is needed whatever the length of the workshift.
Accordingly, OSHA has not added the suggested revisions.
Several commenters (Exs. 2-37, 2-38, and 2-103) stated that there
was a need to define ``competent person.'' OSHA notes that a general
definition of this individual that applies to all construction work
already exists in Sec. 1926.32. Although the definition of competent
person in that section applies to all construction work, OSHA believes
that it is reasonable to repeat this definition of ``competent person''
in the final rule, as a matter of convenience for the user. However,
the Agency notes that the criteria for a ``competent person'' depend on
the situation in which the competent person is working. For example, a
``competent person'' for the purposes of this provision must have had
specific training in and be knowledgeable about the structural
integrity of scaffolds and the degree of maintenance needed to maintain
them. The competent person must also be able to evaluate the effects of
occurrences such as a dropped load, or a truck backing into a support
leg that could damage a scaffold. In addition, the competent person
must be knowledgeable about the requirements of this standard. A
competent person must have training or knowledge in these areas in
order to identify and correct hazards encountered in scaffold work.
Final rule paragraph (f)(4) requires that any part of a scaffold
whose strength has been reduced to less than that required by
Secs. 1926.451(a) shall be immediately repaired or replaced, braced to
meet those provisions, where appropriate, or be removed from service
until repaired. This paragraph applies whenever a scaffold component,
for any reason, lacks the required strength. In particular, under this
provision employers must follow through to address problems identified
pursuant to paragraph (f)(3) of this section. Proposed paragraph (d)(4)
was effectively identical to final rule paragraph (f)(4), except that
the proposal required action only when a competent person determined
that the strength of a part had been compromised, and provided only for
bracing of a part or its removal from service. This provision of the
final rule thus clarifies and consolidates existing Secs. 1926.451
(a)(8) and (o)(6). The proposed paragraph also recognized bracing as an
acceptable means of compliance because OSHA foresaw circumstances where
the removal of a damaged component could be extremely difficult or
hazardous due to its location. However, provision for replacement of a
damaged component was inadvertently left out of the
[[Page 46060]]
proposal. OSHA has included it in the final rule so that the text
clearly expresses the Agency's intent.
Final rule paragraph (f)(5) provides that scaffolds shall not be
moved horizontally while employees are on them, except that mobile
scaffolds may be moved if the provisions of Sec. 1926.452(w) for mobile
scaffolds are followed, and then only if they have been designed by a
registered professional engineer specifically for such movement. Final
rule paragraph (f)(5) is very similar to the proposed paragraph (d)(5)
except that ``laterally'' has been changed to ``horizontally'' for the
sake of clarity. In addition, the proposed exception did not include
scaffolds designed by registered professional engineers specifically
for such movement. The proposed rule was intended to consolidate and
reconcile existing Secs. 1926.451(a)(3) (any scaffold movement must be
conducted under the supervision of a competent person), (e) (6)-(8)
(criteria for moving mobile scaffolds) and (p)(1) (needle beam
scaffolds shall not be moved while in use).
Two commenters (Exs. 2-13 and 2-367) suggested that the Agency
prohibit, in all instances, the moving of mobile scaffolds when
employees are on them, but gave no specific rationale for their
comments. The Agency is not acting on these suggestions because it has
determined that the provisions of final rule paragraph
Sec. 1926.451(f)(7) requiring a competent person to supervise and
direct any movement of a scaffold, and the requirements of
Sec. 1926.452(w), which specifically address the movement of mobile
scaffolds, will provide adequate protection for employees. In addition,
the Agency believes that making employees climb up and down the
scaffold every time it is moved could actually expose them to greater
risk of falling than remaining on a scaffold that is being moved under
the direction of a competent person in accordance with the requirements
of Sec. 1926.452(w).
The SIA (Ex. 2-368) recommended that OSHA add another exception for
some suspension scaffolds which are designed to be moved horizontally
while occupied. The commenter cited as an example scaffolds used for
the construction of bridges and other similar steel structures where it
is impossible to move the scaffold at the ground level. The final rule
allows this type of scaffold to be moved horizontally if the scaffold
has been designed for such movement by a registered professional
engineer.
Paragraph (f)(6) of the final rule addresses the use of scaffolds
near exposed and energized power lines. In particular, this paragraph
requires employers to maintain clearance between power lines and
scaffolds, including any conductive materials on the scaffold. The
minimum clearance for all uninsulated lines and for insulated lines of
more than 300 volts is 10 feet. The minimum clearance for insulated
lines of less than 300 volts is 3 feet. In addition, final rule
paragraph (f)(6)(i) provides that scaffolds and materials may be closer
to power lines than specified above only where necessary to do the
work, and only after the utility company or electrical system operator
has been notified of the need to work closer and the utility company or
electrical system operator has deenergized the lines, relocated the
lines, or installed protective coverings to prevent accidental contact
with the lines.
The final rule provisions in paragraph (f)(6) are very similar to
those in proposed paragraph (d)(6), except that the final rule
addresses materials used on scaffolds; provides an exception for
situations where the employer has contacted the utility company to have
power lines de-energized, relocated or covered to prevent accidental
contact; and sets three feet, rather than two feet, as the minimum
clearance between scaffolds and insulated lines of less than 300 volts.
OSHA has also editorially revised this provision for the sake of
clarity.
The first two changes noted above were made based on input received
in response to Issue L-5 of the hearing notice (53 FR 2051). First, the
ACCSH (Tr. 6/9/87, p. 204) suggested that OSHA revise proposed
Sec. 1926.451(d)(6) to reflect concern that conductive material handled
on a scaffold might contact exposed and energized lines even if the
scaffold itself did not. To this end, the ACCSH recommended that the
introductory language of proposed Sec. 1926.451(d)(6) read as follows:
Scaffolds shall not be erected, used or moved in such a way that
they or any conductive material handled on them can come closer to
exposed and energized power lines than as follows: * * * .
The Edison Electric Institute (EEI) testified (Tr. 190, 3-22-88) in
favor of the suggested language, stating ``[w]e also support your
contention that any conductive extension or persons moving on that
scaffold, the platform, should also comply [with] 10 feet.''
Second, a commenter (Ex. 2-103) suggested that the Agency require
employers to notify the power company when scaffolds are to be erected
near energized power lines and request that the power company de-
energize the line or provide protective covering to prevent accidental
contact.
In Hearing Notice Issue L-5, OSHA indicated its expectation that
adding the suggested language would provide primary employee protection
from electrical shock hazards. The Agency further indicated that
proposed paragraph (d)(6) would apply if the affected employer could
not obtain assurances from the utility company that the lines had been
de-energized or adequately protected from contact.
The SIA testified (Tr. 158, 3-22-88) that the suggested Issue L-5
wording was too vague and recommended that specification-type language,
rather than performance-oriented terminology, ``may be more practical
and enforceable when you are dealing with exposure of this type.'' The
SIA further stated:
We certainly do have the hazard there, particularly in people
erecting the scaffolds and people working on them. There's a great
problem when people go out to erect a scaffold around a building,
there is high voltage wire close by. The question has always been,
well how close can we get to it? Based on California in their table
in some instances they say 6 feet. Some people say that is too close
and I don't know but I think that is really something you need to
address to get input from people who are experts in that area (Tr.
169).
EEI testified (Ex. 11; Tr. 180, 3/22/88) that OSHA should
promulgate the proposed ten-foot minimum clearance between a scaffold
and energized and exposed power lines; that the installation of
protective devices on the power lines be done by ``trained utility line
technicians''; that the ten foot proximity rule should apply to ``any
conductive extension or persons'' on a scaffold (Tr. 190-191); and that
the Hearing Notice Issue L-5 language regarding protective coverings
for energized lines was ``not a safe standard * * *''
In addition, EEI supported requiring employers to notify utilities
before erecting scaffolds in proximity to energized lines, so that the
utilities could determine how to protect scaffold workers. EEI also
stated (Tr. 181):
Any final standard must make it clear that the 10 foot or more
clearances are to be observed unless the line is deenergized or
unless the utility plainly advises the employer that it is safe for
the particular condition involved to erect a scaffold in closer
proximity to the lines than the 10 feet allowed.
It must also be made clear in the final standard that the
utility will have no obligation to be [de]energized or to take steps
to protect lines and that, if the utility deems it appropriate to do
neither, that the 10-foot clearance distance as a minimum * * * must
be observed.
[[Page 46061]]
The EEI described the procedures by which employers contact
utilities when employees need to work in proximity to energized lines,
as follows:
In Wisconsin as part of a one-call system that originated for
digging in the ground to avoid contact with buried facilities. We
have incorporated notification for all electric facilities. So
contractors in Wisconsin who are approaching a job where they detect
the presence of overhead conductors can use the one-call system to
notify the utility of their intent to work. And within 72 hours the
utility comes out and inspects and tells them what they are
proposing is reasonable or not. I am sure there are other states
with similar provisions (Tr. 187).
In response to a question about how work could proceed when a
scaffold must be erected within ten feet of an energized line and the
utility refuses to de-energize the line, EEI testified (Tr. 198) that
the architects and planners for the structure should consider the line
when planning the project. Otherwise, he added, there ``* * * would
have to be a delay until some appropriate protection or alternate feed
for that facility was established.''
Bristol Steel (Exs. 5a-3 and 13) supported focusing attention on
the safeguards necessary to address problems associated with power
lines, stating that the proposed language to require maintaining a safe
distance from power lines or de-energizing the lines to protect
employees from the lines was warranted.
The SSFI (Ex. 5a-19) expressed support for the proposed requirement
that an appropriate distance be maintained between scaffolds and
energized power lines.
The third substantive change made in the final rule to proposed
paragraph (d)(6) was the revision of proposed paragraph (d)(6)(iii) to
increase the minimum clearance between scaffolds and lines to 3 feet
instead of 2 feet. This change was based on the 1990 editions of two
national consensus standards, the National Electrical Safety Code
(NESC) and the National Electrical Code (NEC).
NESC Rule 234C specifies clearances from the nearest conductive
surface to the nearest surface of a building or its projections or its
attachments (scaffolds). The required horizontal clearance to buildings
is intended to provide adequate working space between the conductors or
cables and the building surface to permit workers with small hand tools
to conduct maintenance on a building or other structure. Trained
workers using specialized maintenance tools would also be provided with
adequate clearance.
Specifically, NESC Rule 24C3c(2) states the following:
Service-drop conductors shall not be readily accessible, and
when not in excess of 750 volts, they shall have a clearance of not
less than 3 feet in any direction from windows, doors, porches, fire
escapes, or similar locations.
Section 24C3c(2) was added in the 1984 edition of the NESC to be
consistent with Article 230-24(c) of the NEC. Article 230 of the NEC
covers service conductors.
In the NEC, Article 230-24(c) covers clearances of all overhead
service-drop conductors, and simply refers to Article 230-9,
``Clearances from Building Openings.'' Article 230-9, based on no wind
loading, states the following: ``Service conductors installed as open
conductors or multiconductor cable without an overall outer jacket
shall have a clearance of not less than 3 feet from windows, doors,
porches, fire escapes, or similar locations.''
With no wind loading, the horizontal clearance from the scaffold to
the service conductors must be at least 3 feet. Where wind loading
might cause the conductor to be displaced, the original clearance
distance must be expanded to assure that at least 3 feet of clearance
is maintained between the scaffold and the displaced conductor.
Paragraph (f)(7) of the final rule provides that scaffolds shall
only be erected, moved, dismantled, or altered under the supervision
and direction of a competent person. That paragraph further provides
that the listed activities shall be performed only by experienced and
trained employees selected for such work by the competent person. This
provision is similar to proposed paragraph (d)(7), which was
effectively identical to existing Sec. 1926.451(a)(3).
OSHA received one comment (Ex. 2-23) which recommended the addition
of ``and direction'' between the words ``supervision'' and ``of''
because it would otherwise infer that the supervision need not be at
the scene directing the work. OSHA believes such direct supervision is
necessary, and has revised the final rule to clarify this point. This
commenter also suggested that a qualified person rather than a
competent person be required by this provision. The commenter defined a
qualified person as ``a person designated by the employer who by reason
of experience or instruction is familiar with the operation to be
performed and the hazards involved.'' OSHA acknowledges that the
proposed language does not clearly address the qualifications of a
competent person charged with directing scaffold work. Therefore, the
Agency has revised the language to indicate clearly that the competent
person must be ``qualified'' (as defined in Sec. 1926.32(m)) in the
subject matters for which that person has responsibility.
The Agency has also clarified that the actual work be performed by
experienced and trained employees, selected by the competent person.
This change is based on an ACCSH recommendation (Tr. 88-92, 6-9-87). In
particular, a member of the Advisory Committee stated ``it needs to be
employees that are properly trained and experienced being the only ones
allowed to do this kind of work.'' OSHA agrees with this recommendation
because, unlike other individuals on a finished scaffold, erectors and
disassemblers are exposed to the hazards of working on a partially
completed structure, and a competent person is needed to select the
proper individuals to do this work.
Paragraph (f)(8) of the final rule provides that employees are
prohibited from working on scaffolds covered with snow, ice, or other
slippery material except as necessary for removal of such materials.
This provision is identical to proposed paragraph (d)(8), which was
intended to clarify existing Sec. 1926.451(a)(17). The existing
standard simply required that ``slippery conditions on scaffolds shall
be eliminated as soon as possible after they occur.''
The Agency recognizes that the situation addressed by this
provision differs from situations where workers could be required to
work on scaffolds during storms or high winds, which is addressed by
Sec. 1926.451(f)(12) (discussed below). OSHA notes that snow and ice
removal can be done from ground level on one level built-up scaffolds
(approximately 6 feet) and on suspended scaffolds, since they are
usually accessed at ground level. When dealing with a two or more level
built-up scaffold, removal of slippery material would be conducted
above the 10-foot trigger height requiring normal fall protection
precautions. On the other hand, work on scaffolds during storms or high
winds poses a much greater risk of falling for workers, especially on
tall scaffolds where wind velocity can be much greater than at ground
level. In these situations, materials handling, or even normal
activities such as walking, are adversely affected to the point where
guardrails alone might not be sufficiently protective. Under these
circumstances, the Agency intends the competent person to determine if
the work can be done safely, and the employer to ensure that those
[[Page 46062]]
employees are provided extra protection through the use of personal
fall arrest systems or wind screens. This provision is discussed
further below.
Paragraph (f)(9) of the final rule requires that, where swinging
loads are being hoisted on, to, or near scaffolds such that the loads
could contact the scaffold, tag lines or equivalent measures shall be
utilized to stabilize the loads. This provision is effectively
identical to proposed paragraph (d)(9). The proposed rule was based on
Sec. 1910.28(a)(15), which requires tag lines only when loads are being
hoisted onto the scaffold. The provision covers all hoisting operations
in proximity to scaffolds, because a swinging load can pose a hazard
regardless of its destination. OSHA has made a minor editorial revision
to the proposed rule for the sake of clarity.
Final rule paragraph (f)(10) requires that support ropes used with
adjustable suspension scaffolds have sufficient diameter for
functioning of the brakes and the hoist mechanism. As discussed above
in relation to final rule Sec. 1926.451(a), OSHA has relocated this
provision, which is effectively identical to proposed paragraph
(a)(4)(i), to consolidate the requirements for rope used with
suspension scaffolds.
Paragraph (f)(11) of the final rule requires that suspension ropes
be shielded when a heat-producing process is performed. When acids or
other corrosive substances are used on a scaffold, the ropes shall be
shielded, treated to protect against the corrosive substances, or shall
be of a material which is not adversely affected by the substance being
used. This provision is identical to proposed paragraph (d)(10). The
proposal was essentially the same as existing Sec. 1926.451(a)(18),
which prohibits the use of any heat producing process on scaffolds
supported by fiber or synthetic rope and requires that only treated or
protected fiber or synthetic ropes be used near corrosive substances.
Unlike the existing rule, the revised standard allows the use of heat
producing processes, as long as the ropes are shielded. The provisions
for protection of scaffolds and their components from corrosive
substances and from heat-producing processes are consistent with ANSI
A10.8-1988, Sections 4.27 and 4.28, respectively.
Final rule paragraph (f)(12) prohibits work on or from scaffolds
during storms or high winds unless a competent person has determined
that it is safe for employees to be on the scaffold and these employees
are protected by a personal fall arrest system or wind screens. Wind
screens shall not be used unless the scaffold is secured against the
forces imposed. The proposed rule (paragraph (d)(11)) was based on
general industry regulation Sec. 1910.28(a)(18), which provides that
employees shall not work on scaffolds during storms or high winds.
Proposed paragraph (d)(11) prohibited work on scaffolds during
storms or when wind speeds exceeded 40-mph, unless body belt or harness
systems were used or wind screens were erected. The proposed rule, like
the final rule, provided that wind screens could only be used if the
scaffold was secured against the forces imposed. Issue 6 of the NPRM
requested comments on whether the proposed 40-mph limit was appropriate
and on how to measure the wind speed.
Two commenters (Exs. 2-22 and 2-53) supported the proposed 40-mph
limit. Two other commenters (Exs. 2-13 and 2-41) stated that 25 mph
would be a more appropriate limit. Other commenters (Exs. 2-54 and 2-
64) stated that 40 mph is too high a limit, because of the dangers high
winds present, but did not suggest an alternative limit. Two commenters
(Exs. 2-64 and 2-368) stated that no specific limit should be set
because of the variations in wind speed from ground level to higher
elevations, and from building side to building side. Several commenters
from the AGC (Exs. 2-20, 2-55, 2-70, 2-390, and 2-516) stated that
contractors are presently using ``good judgement'' in determining when
work should cease and that there are no statistics to show otherwise.
The SSFI and the SIA (Exs. 2-367 and 2-368) stated that the most
recent draft language used in the ANSI A10.8 standard should be used.
As adopted, ANSI A10.8-1988, Section 4.22, provides ``[w]orkers shall
not work on scaffolds during storms or high winds.'' In particular, the
SSFI (Ex. 2-367) stated ``[t]here are too many variables for a specific
wind speed to be determined by a governmental agency.'' That commenter
also recommended that OSHA use the term ``high wind'' without
specifying a wind speed, and that the Agency let individual workers
determine if the work should be performed under those conditions. The
SIA (Ex. 2-368) stated ``a set limit of mph can be misleading and
dangerous in that the wind velocity can be 15 mph or lower, yet the
side of the building the men are working on can have gusts in excess of
40 mph. * * * Wind will vary on each side of a building.''
The ACCSH (Tr. 65-79, 6/9/87) recommended that the determination of
wind hazard should be made by a ``competent person.'' OSHA agrees that
designating a competent person to evaluate wind conditions is the
appropriate way to ensure that all the relevant information and the
unique aspects of work locations are considered. OSHA believes this is
a more appropriate way to address the problem than simply specifying a
speed limit without regard to other factors. Accordingly, the Agency
has revised the final rule to reflect the ACCSH suggestion to use a
competent person and the suggestions to use the ANSI language.
Final rule paragraph (f)(13) provides that debris shall not be
allowed to accumulate on platforms, where it could pose a slip, trip,
or fall hazard to employees on or below the platform. This provision is
identical to proposed paragraph (d)(12), which was based on existing
Sec. 1910.28(a)(20). This provision is consistent with ANSI A10.8-1988,
Section 4.24.
Final rule paragraph (f)(14) provides that makeshift devices, such
as but not limited to boxes and barrels, shall not be used on top of
scaffold platforms to increase the working level height of employees.
The Agency has concluded that these makeshift devices will not meet the
pertinent criteria of this final rule, in terms of strength and
stability.
Final rule paragraph (f)(15) prohibits the use of ladders on
scaffolds to increase the employee's working level except when the
employees are on large area scaffolds and the ladder is used in
accordance with the applicable provisions of final rule paragraph
(f)(15)(i)-(iv), discussed below.
The corresponding paragraph in the proposal provided simply that
ladders and makeshift devices not be used to increase scaffold working
heights. This provision was intended to ensure that workers were
provided with a secure work platform, and to eliminate the hazard of
tipping caused by portable ladders exerting a sideways thrust on
scaffold systems. The pertinent provisions are consistent with the
corresponding language in ANSI A10.8-1988, Section 4.29.
NPRM Issue 29 requested public comment on the need for the proposed
prohibition against the use of ladders on scaffolds. Three commenters
(Exs. 2-40, 2-53, and 2-69) favored the use of body/safety belts in
such situations. Of these three, both NIOSH (Ex. 2-40) and another
commenter (Ex. 2-69) noted that there would be no need to prevent the
tipping of a scaffold from sideways thrust exerted by a ladder if the
scaffold were secured laterally. Those commenters added that employees
working above the guardrail system could be guarded from falls by using
a body belt. In addition, NIOSH (Ex. 2-40)
[[Page 46063]]
provided examples, noting that tiebacks, guys, or braces would be used
to secure a scaffold. NIOSH also suggested that OSHA consider requiring
``form scaffolds'' to be near the top of concrete forms. The commenter
indicated that this would ``eliminate the need for workers to be above
the scaffold fall protection system.'' However, NIOSH stated that no
data exist to support this recommendation concerning form scaffolds.
The other commenter (Ex. 2-53) who supported the use of personal fall
arrest systems stated ``safety belts must be used'' when ladders or
other devises are used on top of scaffolds to increase the working
level heights of employees.
One commenter (Ex. 2-15) favored the proposed prohibition of the
use of ladders or makeshift devices to raise the working level of
employees, provided that the prohibition pertains only to scaffolds
subject to tipping that do not completely cover an enclosed area. In
particular, this commenter stated that the proposed prohibition should
not apply to scaffolds built from wall to wall with the entire floor
area covered and with a completely decked top (in effect, a large area
scaffold) from which several trades could use ladders or small
scaffolds to do their work. In addition, two commenters (Exs. 2-1 and
2-54) who addressed proposed paragraph (d)(13), rather than Issue 29,
indicated that ladders can be used on large area scaffolds when
additional precautions are taken.
One commenter (Ex. 2-64) supported applying the proposed
prohibition to suspended scaffolds but did not address other scaffolds.
Another commenter (Ex. 2-13) stated that no ladder or makeshift device
``should be used to increase the height of a scaffold.''
In addition, four commenters (Exs. 2-29, 2-43, 2-367 and 2-368)
explicitly and unconditionally supported the proposed prohibition. Two
commenters (Exs. 2-29 and 2-43) very briefly stated that the use of
ladders and makeshift devices on top of scaffolds to raise working
levels should be prohibited. The SSFI (Ex. 2-367) supported the
proposed prohibition and stated that the use of ladders and makeshift
devices on top of scaffolds makes scaffold systems unstable. The SIA
(Ex. 2-368) supported the proposed prohibition and stated that accident
statistics ``reveal a number of injuries and fatalities due to workers
improvising ladders and makeshift devices to obtain greater working
heights from scaffolds.''
After carefully considering the above comments and the
recommendation from the ACCSH, OSHA has determined that the proposed
prohibition of the use of ladders and makeshift devices on top of
scaffolds is necessary to ensure employee safety. However, the Agency
has also determined that the use of ladders on large area scaffolds is
consistent with efforts to ensure employee safety. As noted above in
the discussion of the definition for ``Large area scaffold'', these
scaffolds cover substantially the entire work area, and are basically
equivalent to working on a floor or large deck of a structure, where
ladders can be used safely. Therefore, the final rule prohibits the use
of makeshift devices on all scaffolds and prohibits the use of ladders
on scaffolds other than large area scaffolds.
Furthermore, the OSHA has determined that the requirements in
proposed Sec. 1926.451(d)(13), which addressed the use of both ladders
and makeshift devices in one provision, should be separated into two
paragraphs so that the final rule clearly expresses the Agency's
regulatory intent. The proposed rule has been revised accordingly.
Final rule paragraph (f)(15)(i) provides that when a ladder is
placed against a structure which is not a part of the scaffold, the
scaffold must be secured against the sideways thrust exerted by the
ladder. This provision was suggested by NIOSH and other commenters on
Issue 29. In addition, paragraphs (f)(15) (ii) through (iv) require
that the platform units be secured to the scaffold to prevent them from
moving; that the ladder legs are all on the same platform unit unless
other means have been provided to stabilize the ladder against platform
unit deflection; and that the ladder legs be secured to prevent them
from slipping and being pushed off the platform unit. These provisions
are based on suggestions made by commenters on Issue 29, as discussed
above.
The Agency believes that compliance with these provisions will
prevent the tipping and instability hazards that led OSHA to propose a
prohibition against the use of ladders on all scaffolds, and has
revised the final rule accordingly.
Final rule paragraph (f)(16) provides that platform units shall not
deflect more than 1/60 of the span when loaded. This provision is
identical to proposed paragraph (d)(14), and is intended to limit the
amount platform units can deflect under load without becoming
overstressed and without their ends being pulled from their supports.
Final rule paragraph (f)(17) requires employers to reduce the
possibility of welding current arcing through suspension wire rope
while employees are performing welding from suspended scaffolds by
insulating the suspended platform and its rigging. OSHA is adding this
new provision to protect employees from the electrocution and platform
collapse hazards posed by arcing welding current. In particular, the
Agency requires that employers rig affected scaffolds with insulated
thimbles (paragraph (f)(17)(i)), insulated wire rope (paragraph
(f)(17)(ii)), and insulated hoist mechanisms (paragraph (f)(17)(iii)).
This paragraph also specifies precautions for grounding the scaffold to
the structure on which welding is being performed (paragraphs (f)(17)
(iv-vi)). These provisions are consistent with ANSI A10.8-1988, Section
6.2.9.
Issue 2 of the NPRM requested comment on the need to regulate
welding equipment used on suspended scaffolds and solicited input
regarding regulatory text then being considered by the ANSI A10.8
Committee. That text, divided into six items, was effectively identical
to the language OSHA has promulgated in paragraph (f)(17).
Four commenters (Exs. 2-20, 2-55, 2-69, and 2-390) stated that this
subject should be covered by the welding standards for construction
(part 1926, subpart J), since the hazards involved in these operations
related directly to welding. The National Constructors Association
(NCA) (Ex. 2-53) went further, saying ``[t]here is no need to regulate
electric welding equipment on scaffolds. NCA member companies do not
have any experience that would indicate additional regulations.''
One respondent (Ex. 2-8) stated that OSHA needed to define the term
``suitable'' as used in describing an insulated thimble (Item (a) of
Issue 2, promulgated as paragraph (f)(17)(i)), because ``[s]omeone
might think that putting electric tape on a metal thimble is
``suitable'' insulation.'' OSHA agrees that the term ``suitable'' could
be interpreted in a way that would result in inadequate insulation and
has adopted regulatory text requiring an ``insulated thimble'' that
provides appropriate protection for the equipment in use.
Another commenter (Ex. 2-13) stated ``[t]he only rule that could
possibly help prevent accidents from welding on suspended scaffolds is
to ground the scaffold. All the scaffold components are conductors and
all could possibly be grounded through the suspension ropes. A
secondary path, of lesser resistance, could possibly help.''
In addition, a commenter (Ex. 2-22) stated that requiring employers
to cover each hoist with protective covers made from insulating
material (Item (c) of Issue 2, promulgated as paragraph (f)(17)(iii))
would have a prohibitive
[[Page 46064]]
cost without having an impact on safety, noting that a ``great number''
of hoists are used on scaffolds. The commenter added that the provision
requiring a grounding conductor to be connected from the unit to the
structure (Item (d) of Issue 2, promulgated as paragraph (f)(17)(iv))
may not be practicable ``because in actual field situations the
machines are constantly and frequently moved.'' In addition, the
commenter stated that the requirement to turn off the welding machine
if the unit grounding lead is disconnected at any time (Item (e) of
Issue 2, promulgated as paragraph (f)(17)(v)) may be impractical,
because ``in actual field situations the machine may be 50 or more feet
from the scaffold.'' Another commenter (Ex. 2-29) suggested that
``[r]equirements should be more performance-oriented to allow
alternative methods to protect the employees working with electric
welding equipment on suspended scaffolds.''
Several commenters (Exs. 2-43, 2-54, 2-64, 2-367, and 2-368)
expressed concern over the hazards of using electric welding equipment
on suspended scaffolds and indicated that they favored promulgation of
the measures raised in Issue 2. One commenter (Ex. 2-64) noted that
OSHA had used the term ``unit'' instead of the terms ``scaffold'' or
``platform'' in Items (d) and (e) of Issue 2 and stated that one of
those other terms should be used instead of ``unit'', for the sake of
clarity. OSHA agrees that the term ``scaffold'' more clearly expresses
the Agency's intent.
In addition, the SSFI (Ex. 2-367) and the SIA (Ex. 2-368) stated
``the specific recommendations developed by OSHA regarding electric
welding equipment are felt to be practical and feasible as several
manufacturers are already using or specifying many of the methods
outlined within the suggested rules.''
Also, on June 9, 1987 (Tr. 26-30), the ACCSH recommended that OSHA
regulate electric welding equipment on suspended scaffolds under
subpart L. In particular, a member of the Advisory Committee stated
``[t]here's a very distinct possibility that you can arc within the
suspended cables, burn the cable and drop the scaffold. That's exactly
why it needs to be addressed.''
Another commenter (Ex. 2-516) expressed concern regarding the
protection provided by insulated thimbles, because ``[a]n insulated
thimble does not prevent the wire rope from hitting the conducting
aluminum skin on the structure and closing the loop. It doesn't stop
the huge current from burning out the power cord and melting the
insulation on the `hot' power leads.'' The commenter also stated that
using more than one ground lead can allow current to ``get loose'',
blowing out adjacent electrical systems and damaging platforms and
their rigging. In particular, the commenter stated ``[p]art of our
problem is that the current from welding machines is high enough to
cause heat damage in metal. The damage manifests itself as melted metal
at the material surface or interface between materials. This damage
seriously reduces strength. Strength is needed to keep the platform
from falling.''
The Agency acknowledges that insulated thimbles, alone, do not
prevent arcing, and that grounding must be undertaken with great care
to minimize stray currents. OSHA has determined that compliance with
the provisions of paragraph (f)(17), taken together, will minimize the
hazards of electric arcing during welding operations on suspended
scaffolds. The Agency has concluded that it is appropriate to address
the hazard of arcing welding current during welding operations on
suspended scaffolds in the final rule for scaffolds, rather than in the
welding standards, because the precautions in question relate to the
scaffold rigging, not to welding procedures, and because placing the
pertinent regulatory text in the rule will facilitate compliance.
Paragraph 1926.451(g) Fall Protection.
Paragraph (g) of the final rule sets fall protection requirements
for employees working on scaffolds, including criteria for guardrail
systems. As discussed above, fall hazards account for a high percentage
of the injuries and fatalities experienced by scaffold workers. OSHA
has determined that compliance with this paragraph will effectively
protect employees from those hazards.
Final rule paragraph (g)(1) sets 10 feet as the threshold height
above which fall protection is required and indicates (paragraphs
(g)(1)(i)--(vii)) what fall protection measures are required for
particular types of scaffolds. In addition, the introductory text
references paragraph (g)(2), which addresses the fall protection
requirements for employees erecting and dismantling supported
scaffolds. Finally, a note has been added at the end of paragraph
(g)(1), to indicate clearly that the fall protection requirements for
employees installing suspension scaffold support systems on floors,
roofs, and other elevated surfaces are set forth in subpart M (Fall
protection) of the construction standards.
Proposed paragraph (e)(1), dealing with fall protection, was
similar, except that it explicitly excluded erectors and dismantlers
from coverage. As with the proposed access provision (proposed
paragraph (c)), OSHA believed at that time that fall protection
requirements would only be feasible when a scaffold was fully erected
and properly braced. The following paragraphs first discuss the issue
of height requirements for fall protection on scaffolds and then
describe the issues surrounding fall protection for erectors and
dismantlers.
The issue of the appropriate height at which to require fall
protection for employees working on scaffolds is complex, involving
analyses of accident statistics, economic issues, strongly held
opinions, and most importantly, concern for employee protection. OSHA
has been involved with this issue since its inception in 1971, when the
Agency adopted, under Section 6(a) of the Act, a requirement that
scaffolds used in construction require fall protection for employees
working at heights greater than 6 feet. By 1972, however, it had become
apparent that this height requirement was proving onerous and causing
disruption for scaffold users in the construction industry, and the
Agency accordingly revised the height requirement to 10 feet (37 FR
25712, December 2, 1972). This change recognized the fact that the
relevant consensus standard, ANSI A10.8-1969, Section 3.3 had set the
threshold height for scaffold fall protection at 10 feet, and that this
had become the industry standard of practice. OSHA's action also
underscored the need for consistency in height requirements for general
industry and construction unless there are compelling reasons for a
different height requirement (the general industry standard's height
threshold had already been set at 10 feet, in accordance with the ANSI
standard). An example of a situation where a different height
requirement is appropriate is the fall protection height requirement
for scaffolds used in shipyards (29 CFR 1915). This height threshold
differs from that in general industry and construction because shipyard
work is less transient and less dynamic than construction work. For
example, it is not uncommon for a scaffold to be erected in the
shipyard environment and to remain in place for several years as
employees work on various vessels that are brought to the scaffold
``work station'' to be repaired. In addition, shipyard facilities are
completed, finished structures, unlike construction sites, where
activities and crews change daily. Finally, the 5-foot threshold for
fall protection on scaffolds has a long history in this industry: it
has been
[[Page 46065]]
standard industry practice since well before OSHA was established.
The fall protection height requirement in the final rule continues
the height requirement that has been in place in OSHA's construction
standards since 1972; this height threshold is also the current
recommendation of the relevant ANSI standard, A10.8-1988. OSHA's
decision on this issue is based on the Agency's professional judgment
and its experience in enforcing this fall protection requirement in the
existing scaffold standards, a review of the available accident
statistics and studies, and an analysis of the record on this issue.
The following paragraphs discuss this information in greater detail.
First, OSHA has been enforcing this limit for almost a quarter of a
century and has found that employers working in all areas of
construction, from commercial building to the specialty trades,
recognize and comply with this limit. In addition, construction workers
are familiar with and have been trained to use fall protection on
scaffolds at heights of 10 feet and above. Thus, this height
requirement reflects current industry practice and is widely observed
by employers and employees alike.
Second, the accident data on falls among construction workers
suggest that several other areas of construction safety--such as
scaffold stability, protection from electrocution hazards, and
protection from falling objects while working on scaffolds--may have a
greater impact on injuries and fatalities than fall protection height.
An unpublished BLS study, entitled Work Injury Report on Scaffolds,
analyzed work injury reports related to scaffolds submitted from May to
November 1978. The study showed that many causes contribute to
scaffold-related injuries and fatalities (Ex. 3-1). For example, one-
quarter of the accidents related to scaffolds occurred while workers
were ascending or descending a scaffold or stepping onto or off a
scaffold, and 72 percent of these accidents occurred when the planking
or support collapsed or slipped (Ex. 3-1).
A recent OSHA review of the Agency's Integrated Management
Information System (IMIS) records of falls in the construction industry
in the period from April 1984 to June 1994 provided information
regarding 32 fatalities and 60 injuries related to work on scaffolds
that occurred during this interval. Of these, only three fatalities and
six injuries involved heights in the 6 to 10-foot range.
OSHA received many comments on the height threshold for fall
protection for work conducted on scaffolds (Exs. 2-3, 2-9, 2-13, 2-14,
2-15, 2-21, 2-22, 2-29, 2-31, 2-40, 2-41, 2-43, 2-45, 2-54, 2-57, 2-69,
2-70, 2-367, 2-368, 2-407, 2-465, 2-595, 5a-3, 5a-5, 5a-17, and, 5a-
19). These commenters argued either for changing the existing rule's
height threshold or for retaining it. Those in favor of a different
limit argued for fall protection at all heights (Tr. 115-116, 6-8-87,
ACCSH transcript), 4 feet (Exs. 2-14, 2-40, 2-45, 2-54, and 2-465), 5
feet (Ex. 2-29), and 6 feet (Exs. 2-15, 2-57). OSHA's Advisory
Committee for Construction Safety and Health (ACCSH) urged the Agency
to require fall protection on all scaffolds, regardless of elevation
(Tr. 115-116, 6-8-87); however, at least one other rulemaking
participant (Ex. 2-594) argued that such a requirement would be
unrealistic. OSHA solicited other comments and data on this ACCSH
recommendation in Issue L-2 of the hearing notice (53 FR 2050), and
received several comments that such a requirement would not be
appropriate (Exs. 5a-3, 5a-5, 5a-17, 5a-19). This group of commenters
urged OSHA to retain the 10-foot requirement.
Those commenters favoring fall protection heights in the 4- to 6-
foot range gave many reasons for their views. For example, one
commenter (Ex. 2-14) stated that falls from heights of four to five
feet could cause serious injuries ``especially if the fall occurs on a
hard surface with debris scattered about.'' According to the Research &
Trading Corporation (Ex. 2-45):
[f]our feet is consistent with current [general industry]
standards for scaffold guarding [Sec.1910.23(c)]. Four feet
according to the NBS study on nets (NBSIR 85-3271) is the height
beyond which a worker is most likely to hit his head when an
accidental fall occurs, which is to be prevented if possible. Six
feet is useful as a universal compromise for OSHA from its current
slew of height requirements. However, it should be no more than six
(6) feet.
Another commenter (Ex. 2-29) argued for five feet on the grounds
that guarding any height above one section of scaffold, which is about
five feet, would be protective. Both the ANSI Z359 committee and Saf-T-
Green (Exs. 2-57 and 2-15) favored a 6-foot fall protection threshold.
Saf-T-Green reasoned that an even lower limit might be preferable but
acknowledged that there is ``some validity to the claim that one can
jump clear of a small, low rolling tower as it tips if there is no
guardrail. However, if the tower does not tip, a guardrail would
protect against the employee falling over the edge.'' Another commenter
(Ex. 5a-3) argued that consistency with the fall protection
requirements of subpart M (Fall Protection) would suggest that a 6-foot
threshold was appropriate for scaffolds.
Many commenters urged the Agency to retain the 10-foot fall
protection threshold for scaffolds (Exs. 2-3, 2-9, 2-13, 2-21, 2-22, 2-
39, 2-43, 2-69, 2-70, 2-367, 2-368, 2-407, 2-595, 5a-3, 5a-5, 5a-17,
5a-19). According to these commenters, it is important to establish the
height at which fall protection is and is not required (Ex. 2-595) and
the 10-foot threshold has proved both protective and cost-effective.
For example, one commenter (Ex. 2-41) stated:
. . . My investigations led me to believe that work at over ten
foot elevated surfaces was at the very least four times as hazardous
as work at grade, and the injuries were far more serious. I did not
feel that any data I saw warranted a conclusion that the increased
injury was due to anything but [a] higher population working at the
[higher] level.
PPG Industries (Ex. 2-43) commented:
PPG has no problem with the 10 foot height as it stands. The
problem lies in the design of the equipment and the failure of
workers to follow safe practices.
OSHA has carefully analyzed all of the comments and data available
in the record and has determined that it is appropriate to maintain the
10-foot fall protection threshold in the final scaffold standard, as
proposed. This is also the height requirement recommended by the
current national consensus standard, ANSI A10.8-1988. This level
differs from the 6-foot threshold for fall protection set in subpart M
(Fall Protection) for other walking/working surfaces in construction
because scaffolds, unlike these other surfaces, are temporary
structures erected to provide a work platform for employees who are
constructing or demolishing other structures. The same features that
make scaffolds appropriate for short-term use in construction, such as
ease of erection and dismantling also make them less amenable to the
use of fall protection at the time the first level is being erected.
For example, there may be no secure place on the first level for the
installation of guardrails or personal fall arrest systems. Also there
is often no structure adjacent to a scaffold when the first level has
been erected that can be used to anchor a personal fall arrest system,
because the adjacent structure is in the process of being built or
demolished.
This scaffold standard contains many updated and strengthened
requirements for safe erection and maintenance of scaffolds. In
particular, the final rule
[[Page 46066]]
sets clear, performance-oriented requirements for scaffold capacity
(Sec. 1926.451(a)); erection (Secs. 1926.451 (b), (c) and (d)); access
(Sec. 1926.451(e); and use (Sec. 1926.451(f)). The Agency has
determined that compliance with the above-noted requirements will
prevent many of the fall-related injuries and fatalities that would
otherwise result from structural collapse or instability, including
those occurring on scaffolds less than 10 feet in height, because
properly erected scaffolds will not collapse during use.
In addition, OSHA intends to monitor the extent to which compliance
with these revised subpart L requirements for structural integrity
effectively protects employees on scaffolds from fall hazards when they
are working between six and 10 feet above lower levels. At this time,
the data are insufficient to persuade the Agency that the existing 10-
foot threshold needs to be changed. OSHA will carefully review and
examine its enforcement data over the next several years, together with
any investigative reports and other information on incidents that
involve fall hazards. The Agency also intends to work closely with
NIOSH in performing such data collection and analysis. Should it appear
that compliance with this final rule is not providing adequate fall
protection for employees working on scaffolds between six and 10 feet
above lower levels, the Agency will reevaluate the standards and
determine what changes, if any, are warranted.
Paragraphs (g)(1)(i) through (vii) of the final rule specify the
types of fall protection to be used on particular types of scaffolds.
These provisions are essentially the same as the corresponding proposed
provisions, except as discussed below. The proposed and final rule
provisions effectively clarify and consolidate the fall protection
requirements in existing Sec. 1926.451(a)-(y), Sec. 1926.500(c)(2), and
Sec. 1926.1910.29(a)(3)(vii).
Paragraph (g)(1)(i) of the final rule, like proposed paragraph
(e)(1)(i), recognizes that personal fall arrest systems, not
guardrails, are appropriate for use on boatswains' chairs, catenary
scaffolds, float scaffolds, needle beam scaffolds, and ladder jack
scaffolds. This provision consolidates the following paragraphs of the
existing rule Secs. 1926.451(1)(4)--boatswains' chairs; (p)(9)--needle
beam scaffolds; (w)(6)--float scaffolds; and Sec. 1926.752(k)--float
scaffolds for steel erection. This requirement is being applied to
catenary scaffolds and ladder jack scaffolds for the first time.
Paragraph (g)(1)(ii) of the final rule, like proposed paragraph
(e)(1)(ii), requires personal fall arrest systems and guardrail systems
for all single-point adjustable suspension scaffolds (except
boatswains' chairs), and for all two-point adjustable suspension
scaffolds. The requirement to have guardrails and personal fall arrest
systems on two-point scaffolds, which carries forward language in
Sec. 1926.451(i)(8) of the existing rule, is based on the fact that a
guardrail system alone does not provide adequate fall protection when a
suspension rope fails and causes the scaffold to tip or hang from only
one end. Personal fall arrest system protection is also necessary for
single-point systems, because the fall hazard related to suspension
rope failure is as serious as it is with the two-point scaffold.
However, because personal fall arrest systems would be the primary
means of fall protection on single-point and two-point systems, the
provision allows a lower minimum strength guardrail system to be used.
This approach is consistent with that taken in the proposed rule.
Paragraph (g)(1)(iii) of the final rule provides that ``Each
employee on a crawling board (chicken ladder) shall be protected by a
personal fall arrest system, a guardrail system (with minimum 200 pound
toprail capacity), or by a three-fourth inch (1.9 cm) diameter grabline
or equivalent handhold securely fastened beside each crawling board.''
This provision, like proposed paragraph (e)(1)(iii), is essentially the
same as paragraph 1926.451(v)(2) of the existing rule, except that the
existing rule permits grablines (lifelines) or equivalent handholds if
they are securely fastened alongside crawling boards.
Paragraph (g)(1)(iv) of the final rule, like proposed paragraph
(e)(1)(iv), provides that employees on self-contained scaffolds be
protected by both personal fall arrest systems and guardrail systems
when the platform is supported by ropes (as when the scaffold is being
raised or lowered on some systems) and by guardrail systems when the
platform is supported directly by the scaffold frame.
Paragraph (g)(1)(v) of the final rule, similar to proposed
paragraph (e)(1)(v), requires guardrails to be used along scaffold
walkways and to be located within 9\1/2\ inches horizontally of at
least one side of the walkway. OSHA originally proposed that the
walkways be located within 8 inches horizontally of the side of the
walkway. However, for consistency with final rule
Sec. 1926.451(b)(1)(ii), the provision has been revised to allow an
open space of up to 9\1/2\ inches. The provision that guardrails need
only to be provided along one side applies only when the platform is
used solely as a means of access to get from one point on the scaffold
to another. If work activities other than access are performed on or
from the walkway, then the platform is not considered to be a walkway
(see definition of ``walkway''), and other provisions of paragraphs
(g)(1), as appropriate, would apply.
Paragraph (g)(1)(vi) of the final rule provides that fall
protection (i.e., a personal fall arrest system or guardrail) be
provided on all open sides and ends of scaffolds from which employees
are performing overhand bricklaying operations and/or related work,
except those sides and ends next to the wall being laid. This
requirement replaces a note that followed proposed paragraph (e)(1)(v),
which stated that the fall protection requirements for employees
performing overhand bricklaying from supported scaffolds are provided
in Sec. 1926.501, Fall protection (subpart M). OSHA has deleted the
note from the final rule because the Agency has determined that, except
for some system criteria which are referenced from subpart M, it is
appropriate to cover all scaffold fall protection in this final rule
for scaffolds in construction (subpart L).
Paragraph (g)(1)(vi) of the final rule is consistent with
Sec. 1926.501(b)(9), which addresses fall protection for employees
performing overhand bricklaying while on elevated surfaces other than
scaffolds.
Final paragraph (g)(1)(vii) requires that employees on scaffolds
not addressed elsewhere in paragraph (g)(1) be protected either by
guardrails or personal fall arrest systems. This provision is
essentially the same as the fall protection requirement of proposed
paragraph (e)(1), except that the term ``body belt/harness systems or
Type 1 guardrail systems'' has been replaced by ``personal fall arrest
systems or guardrail systems'' for the reasons discussed above.
Paragraph (g)(1) does not apply where there are no ``open sides or
ends'' on the scaffold (see definition in Sec. 1926.451(b)). For the
scaffold to be considered completely enclosed, no perimeter face of the
scaffold may be more than 14 inches from a wall. The requirements for
fall protection will apply at openings such as hoistways, elevator
shafts, stairwells, or similar openings in the scaffold platform, or
openings in the walls of the structure surrounding the platform.
Proposed paragraph (e)(2) stated that each employee on a platform
(except for a self-contained adjustable scaffold or a scaffold type
covered by Sec. 1926.452), less than 45 inches (1.1 m) wide, and 4
[[Page 46067]]
feet (1.2 m) or more above lower levels, shall be protected from
falling to those lower levels by the use of a personal fall arrest
system or guardrail system (with minimum 200 pound toprail capacity).
Proposed paragraph (e)(2) also provided a blanket exemption for
erecting/dismantling activities and referred to the use of a ``Type I
guardrail system.''
This provision, based on existing Sec. 1926.451(a)(4), has been
dropped in the final rule because further analysis of the requirement
showed that there was no real definable target for the requirement and
that 99% of scaffolds would be excluded by the proposed provision.
Paragraph (g)(2) of the final rule addresses fall protection for
employees erecting or dismantling supported scaffolds. Based on the
rulemaking record, developed through NPRM Issue 8 discussed below, OSHA
has determined that it is appropriate to delay the implementation of
paragraph (g)(2) until September 2, 1997. The delay will allow affected
employers sufficient time to implement the appropriate procedures for
addressing the fall protection needs of employees erecting or
dismantling scaffolds. In addition, deferring compliance will allow
time for the Agency to complete non-mandatory Appendix B, which will
provide examples of considerations that a competent person would take
into account when evaluating fall protection options for scaffold
erectors and dismantlers. As discussed above in relation to final rule
paragraph (e)(9), the Agency has also deferred requirements for safe
access for scaffold erectors and dismantlers until September 2, 1997.
Final paragraph (g)(2) requires that employers whose employees
erect or dismantle supported scaffolds after September 2, 1997 ensure
that a competent person determines the feasibility and safety of
providing fall protection for such employees. This paragraph further
requires that affected employers provide fall protection for employees
erecting or dismantling supported scaffolds where the installation and
use of such protection is feasible and does not create a greater
hazard.
NPRM Issue 8 solicited comments concerning the proposed exemption
of employers whose employees perform scaffold erection and dismantling
operations from the fall protection requirements of proposed
Sec. 1926.451(e)(1). The Agency noted that, while supported scaffolds
often do not have a place to which personal fall arrest systems can be
properly attached, suspended scaffolds are often located such that
personal fall arrest systems can be used.
On March 29, 1993, based on the response to Issue 8, OSHA reopened
the public record for proposed subpart L (58 FR 16509) to obtain more
information. The Agency stated that the rulemaking record supported
deleting the proposed exemption of suspended scaffolds and indicated
that a blanket exemption for supported scaffolds might be
inappropriate. In particular, OSHA asked if employers should be
required to provide fall protection for employees erecting or
dismantling supported scaffolds, except where an employer can
demonstrate that providing fall protection was either ``impracticable''
or ``would create a greater hazard.'' The Agency also sought
information about current efforts and the ability to provide fall
protection for employees erecting or dismantling scaffolds. In
addition, OSHA asked if it was appropriate to require fall protection
for those portions of a supported scaffold that have been, or remain,
fully assembled, while exempting those areas where erecting or
dismantling is underway.
The responses to NPRM Issue 8, and the March 29, 1993, reopening of
the record on this Issue fell into two broad groupings. The first group
either supported an across-the-board exemption from fall protection
requirements for all erectors and dismantlers (Exs. 2-3, 2-9, 2-12, and
2-21); or supported an exemption for erectors and dismantlers of
supported scaffolds only (Exs. 2-13, 2-15, 2-30,
2-69, 2-367 and 2-368); or specifically opposed a fall protection
requirement for erectors and dismantlers, even with an exception for
impracticability or greater hazard, favoring instead trained erectors
and dismantlers, a hazard awareness program, controlled access zones,
or a standardized procedure for erecting and dismantling scaffolds
(Exs. 34-5, 34-9, 34-10, 34-12, 34-17, 34-17, 34-20, 34-31, 34-32, 34-
37, and 34-43).
The second group either supported a requirement for fall protection
at all times, including during erecting and dismantling (Exs. 2-22, 2-
43, 2-45, 2-53, 2-497, 34-4, 34-11, and 34-35) or supported a
requirement for fall protection except where the employer demonstrates
that it is infeasible, unsafe, or creates a greater hazard during
erecting and dismantling operations (Exs. 2-29, 2-54, 2-57, 2-70, 34-2,
34-18, 34-19, 34-22, 34-26, 34-29, 34-34, and 34-46). Each of these
arguments is discussed below, along with OSHA's response to the points
raised by the commenters.
Commenters that supported the proposed total exemption of erecting
and dismantling operations from the fall protection requirements argued
(Ex. 2-3) ``[t]his is a situation where someone must be exposed in
order to do the job * * *''; or felt that fall protection would be
detrimental to employee safety (Exs. 2-12 and 2-21). OSHA disagrees
with these commenters and notes that the record describes many
situations where it is feasible to provide fall protection for erectors
and dismantlers.
Commenters that supported a fall protection requirement for
erectors and dismantlers of suspended scaffolds, but not supported
scaffolds (Exs. 2-13,
2-15, 2-30, 2-69, 2-367, and 2-368) argued that it is feasible and
practical to require such protection for suspended scaffolds, but not
for supported scaffolds, due to the lack of an appropriate tie-off
area, and the possibility of drop lines becoming entangled during
climbing and moving procedures which could pull the erector off the
supported scaffold. The Agency agrees with these commenters that it is
virtually always feasible to provide fall protection for workers
erecting or dismantling suspended scaffolds because structures that are
capable of supporting a suspended scaffold are also capable of
providing a safe anchor point for personal fall protection equipment.
On the other hand, OSHA finds that the record does not support an
across-the-board exception from the requirements for fall protection
for erectors and dismantlers of supported scaffolds.
Another group of commenters opposed a fall protection requirement
but emphasized the importance of training in maintaining safety during
erecting and dismantling operations. For example, some commenters (Exs.
34-9, 34-10, 34-12, and 34-17) recommended the following:
1. A formal hazard awareness program shall be implemented.
2. Enforce ``controlled access zones'' allowing only those
people trained in the erection and dismantling of scaffolds to be
present.
3. Develop and strictly enforce standard procedures for the
erection and dismantling of scaffolding. These procedures may
include but not be limited to the following:
a. Fully planking each level before moving on to the next
highest level.
b. Fully securing each level with the proper guardrails prior to
moving to the next higher level.
c. Providing proper access to all completed levels.
d. Develop methods for placing components on upper levels
without placing unnecessary risks on employees.
e. Only those employees actually involved in the erection or
dismantling shall be allowed on the scaffolding.
[[Page 46068]]
The Agency recognizes the importance of training and hazard
awareness programs to employee safety, but finds that these precautions
alone are not adequately protective because site conditions change and
mistakes are made. The Agency finds that providing appropriate fall
protection, whenever it is feasible or will not create a greater
hazard, is the best way to ensure that erectors and dismantlers are
appropriately protected from fall hazards.
The second group consisted of commenters that supported fall
protection for erectors and dismantlers under some (Exs. 2-29, 2-54, 2-
57, 2-70, 34-2, 34-19, 34-22, 34-26, 34-29, and 34-46) or all
conditions (Exs. 2-22, 2-43, 2-45, 2-53, and 2-497). For example, some
commenters argued that if a fall hazard exists, lifelines or some other
fall arresting system should be in place. R&TC (Ex. 2-45) stated:
The use of lightweight outrigger scaffold sections with guard
rails, which can be pushed up the vertical scaffold poles prior to
the new upper level height exposure during erection, seems to be
promising as a fall protection means * * * Furthermore, many
structures can provide overhead anchorage points for workers during
scaffold erection and dismantling without such special scaffold
platforms. For these situations, regular lifelines can easily be
used for vertical and horizontal movement.
R&TC later added (Ex. 2-497) ``[w]hen an overhead anchorage is
available, a bucket truck, manlift or other elevating platform can be
used to install lifelines without a fall hazard.''
Commenters to the Reopening Notice (Exs. 34-4, 34-11, 34-18, and
34-35) also supported a fall protection requirement for erectors and
dismantlers.
Some, such as Dynamic Scientific Controls (DSC) (Ex. 34-18)
provided input on ways to provide fall protection for erectors and
dismantlers. In particular, DSC provided a video showing a scaffold
being erected by an employee who uses a retractable lanyard attached to
the scaffold for fall protection. DSC stated that this method has been
improved by crossbracing the first frame, tying-in to the structure,
using the pulley bracket more often for attaching lifelines in order to
reduce the lifeline angle to less than 45 degrees, and pinning legs
before attaching the lifeline to a higher level. DSC added that using
horizontal lifelines within each frame and extending the length of the
scaffold can provide protection to workers as well. This commenter
noted, however, that any fall arrest system attached to a scaffold
should be an engineered system modelled for that type of scaffold, or
should be designed by a skilled professional engineer.
In addition, the United Brotherhood of Carpenters and Joiners (Ex.
34-11) stated that the ability to provide fall protection can be
greatly increased through modified erection, engineered attachment
points designed into structures, additional scaffold bracing, guying,
and outrigging.
Finally, DBI/SALA (Ex. 34-4) offered the following choices for fall
protection: ``(1) Provide for or suggest a means for a feasible anchor;
(2) If the current state of the art doesn't allow scaffolds to be used
as anchors, maybe a redesign incorporating outriggers or whatever is
required is appropriate.''
The Agency agrees that, if fall protection can be provided, it is
the employer's responsibility to take the actions necessary to protect
employees. However, OSHA has determined, based on the information in
the record, that in some situations, it is not possible to provide fall
protection for erectors and dismantlers of supported scaffolds.
Two commenters, Dynamic Scientific Controls (DSC) (Ex. 34-18) and
the State of Hawaii (Ex. 34-34) commented that the employer should be
required to show that fall protection is infeasible or creates a
greater hazard for the scaffold erector in order to avoid providing
fall protection. Another commenter (Ex.
2-54) added that employers ``should note in their Daily reports why
they can't take [the] necessary precaution[s].''
OSHA agrees that employers must have valid reasons for not
providing fall protection to scaffold erectors and dismantlers, but
does not agree that the employer must put these reasons in writing.
Compliance officers can substantiate employer claims of infeasibility
or greater hazard through on-site observations and discussion with the
competent person and other workers.
Many commenters (Exs. 2-29, 2-54, 2-57, 2-70, 34-2, 34-19, 34-22,
34-26, 34-29, and 34-46) supported a fall protection requirement for
scaffold erectors and dismantlers, if feasible, or unless it would
create a greater hazard. These commenters also provided insight into
the potential problems of providing fall protection for erectors and
dismantlers, and into the factors that must be considered when
determining if fall protection is feasible in a particular situation or
if the use of fall protection would create a greater hazard.
For example, the ANSI Z359 Committee (Ex. 2-57) stated:
It is recognized that fall protection may, in general, be
difficult or impractical to provide in erection and dismantling of
supported scaffolds. This may be due to absence of suitable
anchorages whether independent or integral to the scaffold. However,
there are notable exceptions when independent overhead anchorages
exist which may be used for vertical or horizontal lifelines.
Further, some supported scaffolds can be rigged to provide integral
fall protection without undue encumbrance of the work. There is
concern that granting a broad exemption from fall protection
requirements for supported scaffold erection/dismantling would
reduce the protection even where it is today feasible. Such
exemptions could also discourage future development of fall
protection means to address this subject.
Miller & Long (Ex. 2-70) commented ``If there is an area where
employees can tie off they should do so.''
The Boeing Company (Ex. 34-19) stated that fall protection for
erectors and dismantlers could be provided through the use of boom
supported elevated work platforms, scissors lifts, forklift platforms,
temporary guardrails, fall arrest/restraint systems or other scaffolds.
The Scaffold Training Institute (STI) (Ex. 34-20) indicated that
100% fall protection for erectors is not achievable from a practical
standpoint due to a lack of suitable anchorages. The Institute also
stated that lifelines would become entangled in pipes, lines, platforms
tubes, braces or other obstructions. STI was particularly concerned
that snagged lifelines would restrict the motion of employees and could
lead to falls for erectors whose work requires that they have freedom
of motion in order to carry and to maneuver into place large, bulky
components. The commenter added that the use of lanyards and lifelines
can lead to increased fall hazards, and that a pendulum effect is
created if an erector falls while attached to a lifeline that is
anchored several feet away.
Duke Power (Ex. 34-29) stated ``[f]all protection harnesses tend to
snag on things, butt straps hinder climbing . . . Fall protection also
slows people down.''
SINCO (Ex. 34-22) stated that the effect on the mobility of
employees varies with conditions and the type of fall protection
equipment used, but stated that the effect can be limited by proper
pre-planning and project management. In addition, both SINCO and
Professor Ralph E. Bennett of Purdue University (Ex. 34-26) suggested
that the scaffold must be properly tied or braced, with all components
pinned together, and, that intermediate plank levels be provided to
limit fall height during erection of the uppermost levels.
In addition, SINCO recommended that OSHA require affected employers
to satisfy the following criteria for exemption:
[[Page 46069]]
A qualified person has determined that fall protection
creates a greater hazard than falling freely to the ground or the
closest possible level;
Tests prove that a scaffold or structure would definitely
fail if used as an anchorage;
There are no other means of fall protection available;
Employees have been trained in the recognition and
avoidance of hazards by use of the employer's prescribed methods of
erection; and
Compliance with the requirement for fall protection is
likely to result in a more serious injury compared to the possibility
of a life saved . . .''
SINCO observed that a greater hazard may exist if a falling person
could pull a scaffold over. However, the commenter added that this
hazard would involve more danger to employees on the ground than to
employees on the scaffold. They contended that other employees on the
scaffold may provide ``counter-balance'' that would prevent the
scaffold from overturning. In addition, SINCO stated that this hazard
can be prevented by reinforcing the scaffold's base through the use of
outriggers, counterweights, or tie-downs. The commenter added that this
hazard can be greatly reduced by requiring erectors to remain inside
the frames to decrease any eccentric loading and through the use of
shock absorbers.
Dow Chemical Co. (Ex. 34-46) commented that since each worksite is
unique, fall hazards must be addressed through preplanning of the work
with the aim of eliminating fall hazards and preventing falls. However,
the commenter added, where fall hazards cannot be eliminated, a fall
protection system should be used if it ``provides a more appropriately
safe solution''. Dow also stated that a lanyard long enough to allow
mobility can create tripping hazards and the potential for one worker
to ``pull another worker from their task.'' The commenter added that
``people on-site must have the latitude to address [these hazards].''
OSHA notes that the Agency's own compliance experience concerning
the potential problems of providing 100% fall protection for erectors
and dismantlers is consistent with the positions put forth by the
commenters. OSHA has determined that it would be useful to provide
examples of the factors to be considered by a competent person when
deciding what fall protection is appropriate for employees erecting or
dismantling supported scaffolds. Accordingly, the Agency has reserved
non-mandatory Appendix B, and will be developing informational text
that can be added to subpart L at a later date to serve as a guide to
assist employers in evaluating their worksite conditions.
Several commenters (Exs. 34-8, 34-9, 34-10, 34-12, 34-17, 34-22,
and 34-26) addressing the topic of fall protection for erectors and
dismantlers took no position as to an exception for these workers.
However, they indicated that fully planking sections could reduce
exposure to fall hazards. One of these commenters (Ex. 34-8) stated
that, although full planking and stairway-type ladders would reduce
exposure, their use is not always practical. In addition, four of these
commenters (Exs. 34-9, 34-10, 34-12, and 34-17) stated that ladders
attached at the end of the scaffold would be better because stairway-
type ladders greatly reduce employee movement along the length of the
scaffold.
Four other commenters (Exs. 34-32, 34-35, 34-37, and 34-39)
indicated that such practices would be either infeasible or would
create other hazards. The SIA and SSFI (Exs. 34-37 and 34-32) added
that planking every level would overload tall scaffolds and that
stairways are not needed because erectors do not continually climb up
and down. The SIA also said that fully planking every level would
require that all equipment be hoisted outside the scaffold, creating
additional hazards. Another commenter (Ex. 34-46) stated that a
requirement for fully planking sections ``would unnecessarily restrict
local decisions for safety.''
The Agency has determined that, due to the large variety of
supported scaffolds and an infinite number of unique site conditions
that could affect the feasibility or safety of providing fall
protection, neither a blanket exception nor a requirement for 100% fall
protection is appropriate for erectors and dismantlers. OSHA agrees
with commenters (Exs. 34-8, 34-22, 34-36, and 34-46) that the people on
site (competent person) must have the flexibility to address fall
hazards for erectors and dismantlers on a site-specific basis.
Therefore, OSHA finds that the determination of what fall protection is
feasible and can be used safely at a given worksite should be made by a
competent person at the worksite. The competent person will need to
have the ability and knowledge to decide whether fall protection can be
provided for erectors and dismantlers under the specific site
conditions, and, if so, what measures are appropriate.
Therefore, the Agency has revised the final rule to reflect this
finding, while deferring compliance for one year to allow time for
employers to develop and implement the appropriate procedures. In
addition, as noted above, the Agency will be adding non-mandatory
Appendix B at a later date, to provide examples of situations where it
is feasible to provide fall protection during the erection and
dismantling of supported scaffolds and the criteria the competent
person would consider when deciding the appropriateness of fall
protection during erection and dismantling. Interested parties are
invited to provide OSHA with suggestions and information regarding the
appropriate guidance for the competent person.
Paragraph (g)(3) of the final rule provides that personal fall
arrest systems must comply with the pertinent provisions of
Sec. 1926.502(d) and, in addition, must be attached by lanyard to a
vertical lifeline, horizontal lifeline, or scaffold structural member.
However, when overhead obstructions such as overhead protection or
additional platform levels are part of a single-point or two-point
adjustable suspension scaffold, then vertical lifelines must not be
used, because, in the event of a scaffold collapse, the overhead
components would injure an employee who was tied off to a vertical
lifeline. This provision is essentially the same as proposed paragraph
(e)(3), except that the terms ``dropline'' and ``trolley line'' have
been replaced by the terms ``vertical lifeline'' and ``horizontal
lifeline'' to be consistent with the terms used in subpart M of this
part--Fall Protection.
Paragraph (g)(3)(i) of the final rule requires that vertical
lifelines, when used, be fastened to a fixed safe point of anchorage,
be independent of the scaffold, and be protected from sharp edges and
abrasion. Based on concern that inadequate anchor points may be used,
this paragraph also incorporates the language of the note to proposed
Sec. 1926.451(e)(3), which stated that safe points of anchorage include
structural members of buildings, but do not include standpipes, vents,
other piping systems, electrical conduit, outrigger beams, or
counterweights. This is the same requirement as was proposed in
paragraph (e)(3)(i) of the NPRM and is consistent with the
corresponding language in Sec. 1926.451(i)(8) of the existing rule.
Paragraph (g)(3)(ii) of the final rule states that horizontal
lifelines, when used, shall be secured to two or more structural
members of the scaffold, and shall not be attached only to the
suspension ropes. This is the same requirement as was proposed in
paragraph (e)(3)(ii). It is designed to provide protection to the
employee in the event of a suspension line failure.
[[Page 46070]]
Paragraph (g)(3)(iii) of the final rule provides that, when
lanyards are connected to horizontal lifelines or structural members on
a single-point or two-point adjustable suspension scaffold, the
scaffold must be equipped with additional independent support lines and
automatic locking devices capable of stopping the fall of the scaffold
in the event one or more of the suspension ropes fail. The independent
support lines must be equal in number and strength to the suspension
ropes. This is the same requirement as proposed paragraph (e)(3)(iii).
OSHA believes that in the event of a suspension rope failure, the
additional support lines will keep the scaffold from falling.
Paragraph (g)(3)(iv) of the final rule provides that vertical
lifelines, independent support lines, and suspension ropes must not be
attached to each other, or be attached to or use the same point of
anchorage, or be attached to the same point on the scaffold or body
belt/harness system. This is essentially the same provision as proposed
paragraph (e)(3)(iv), except that the requirements in the final rule
also prohibit the attachment of lines and ropes ``to the same point on
the scaffold or personal fall arrest system.'' This language reflects
the incorporation of the note that accompanied proposed paragraph
(e)(3) into paragraph (g)(3)(i) of the final rule, as discussed above.
Issue 19 in the preamble to the proposed rule noted that some
single-point adjustable suspension scaffolds which are currently in use
have two separate lines (one serves as an independent support line)
attached to two separate anchor points; however, both lines are
connected to a single point on the body support system. A failure of
this single body support mechanism, or body support system, could
result in an uncontrolled fall for the employee. OSHA sought comments
on the question of whether the final rule should permit the use of such
a system. The Agency also asked what criteria would need to be set to
ensure that a single mechanism or body support system prevented
failures. In addition, OSHA inquired about industry experience with
this type of system.
Several commenters (Exs. 2-29, 2-312, 2-367, and 2-368) and the
ACCSH (Tr. 6/9/89, pp. 150-151) were in agreement that OSHA should not
permit the use of systems of the type described in Issue 19. One
commenter (Ex. 2-29) stated simply that ``the standard should not allow
single-point suspension scaffolds with two separate support lines to be
connected to a single point on the body support system.''
The SSFI (Ex. 2-367) recommended ``that OSHA not permit the use of
a lifeline and support line being tied to a single mechanism or body
support system. It is our opinion that the lifeline should be an
independent anchorage with independent support.'' Also, the SIA (Ex. 2-
368) stated:
We are opposed to the use of systems in which the lifeline and
support line connect to a single mechanism or body support system.
The primary suspension line and an independent fall arrest system
should each be anchored to separate body support devices, so that in
the event one line fails, the other will provide protection. The
cost would be equal to the cost of the original suspension, but
could be negligible in many instances.
After a careful review of the comments, OSHA has determined that
the purpose of having separate lines would be defeated if lines were
attached to a single point at either end and that point of attachment
failed, and the final rule (paragraph (g)(3)(iv)) reflects this
determination.
Final rule paragraph (g)(4) sets criteria for guardrail systems
used to provide fall protection for employees working on scaffolds.
These provisions are consistent with the corresponding language of
recently revised subpart M of this part, Fall protection, except as
necessary to address the particular circumstances of construction work
performed from scaffolds.
Paragraph (g)(4)(i) of the final rule provides that guardrail
systems be installed along all open sides and ends of platforms. This
requirement is effectively the same as proposed paragraph (e)(4)(i) and
existing Sec. 1926.451(a)(4). OSHA has added language which clarifies
when guardrails would need to be in place. In the case of suspended
scaffolds, guardrails must be installed before any employee is allowed
on a hoisted scaffold. In the case of supported scaffolds, installation
must occur before employees are permitted to work from the scaffold.
When an employee is on a supported scaffold during the scaffold
erection process, fall protection is covered by final rule paragraph
(g)(2). This clarification is based on language in the State of
California Code, Title 8, paragraph 1637(i)(6) which was submitted to
the docket by the California Department of Industrial Relations (Ex. 2-
23).
Paragraph (g)(4)(ii) of the final rule provides that the top edge
height of toprails or equivalent members on supported scaffolds
manufactured or placed into service after January 1, 2000 must be
between 38 inches (0.97 m) and 45 inches (1.2 m) above the platform
surface. Furthermore, the top edge height of guardrails on supported
scaffolds manufactured and placed into service before January 1, 2000
and on all suspended scaffolds where both a guardrail and a personal
fall arrest system are required must be between 36 inches (0.9 m) and
45 inches (1.2 m). The final rule also provides that toprail height may
exceed 45 inches if the other criteria of paragraph (g)(4) have been
satisfied.
In the proposal, paragraph (e)(4)(ii) proposed a toprail height
between 38 and 45 inches above the platform surface when the guardrail
is the sole means of providing fall protection, and a toprail height
between 36 and 45 inches when the guardrail is used in conjunction with
a personal fall arrest system. The proposed minimum 36-inch toprail
height reflected OSHA's belief that the minimum height requirement for
a guardrail used with personal fall arrest systems should be less than
that for a guardrail on which employees rely for fall protection.
As discussed in the proposed rule (51 FR 42690), the 38-inch lower
limit on guardrail height was proposed in lieu of the 39-inch lower
limit on guardrail height allowed by subpart M (Fall protection) to
allow for guardrail height differentials caused by scaffold platform
unit arrangements. In particular, a frame constructed to hold a toprail
42 inches above a flush-mounted prefabricated deck would be only 40
inches above a scaffold platform made with two-inch solid sawn planks.
If the scaffold planks are overlapped to form a long platform, the
guardrail height would drop to 38 inches.
In addition, the Agency has determined that employers should have
the flexibility, when conditions warrant, to use toprails with heights
higher than 45 inches, so long as the other protective criteria of
paragraph (g)(4) are satisfied. The language of the proposed rule has
been revised to reflect this flexibility. The language of paragraph
(g)(4)(ii) of the final rule is consistent with the corresponding
language in Sec. 1926.502(b)(1), Fall protection (subpart M).
Issue 12 of the preamble to the proposed rule sought comments on
whether OSHA should adopt the language in the 1977 edition of ANSI
A10.8-1977, paragraph 3.3, which sets 36 inches above the work platform
as the minimum guardrail height and on the effectiveness, feasibility
and cost savings of requiring guardrails to be at least 36 inches high.
Issue 12 noted that existing Sec. 1926.451(a)(5), which requires that
guardrails be ``approximately'' 42 inches high, has been interpreted
over
[[Page 46071]]
the years by OSHA to allow a range of 36 inches to 45 inches above the
work platform. These interpretations, dating from 1979, are based on
OSHA Program Directive #200-67 (Revision 1), issued on October 24,
1978, and later renumbered as OSHA Instruction CPL 2.11A. OSHA notes
that the 1988 edition of the pertinent ANSI standard, A10.8-1988,
paragraph 4.5.1, accepts toprails that are installed between 36 and 45
inches above lower levels.
OSHA received many comments on the issue of guardrail heights (Exs.
2-9, 2-12, 2-13, 2-20, 2-21, 2-29, 2-41, 2-50, 2-53, 2-54, 2-55, 2-64,
2-69, 2-367, 2-368, 2-390, 2-476, and Tr. 6/9/87, pp 116-121). The
comments received ranged from those stating that 36 inches was too low
for the bottom of the range, that 36 inches was appropriate, that 45
inches was too high for the top of the allowable range of guardrail
heights, and that no change should be made to the range allowed by
existing OSHA interpretations (i.e., that allowable heights be between
36 and 45 inches above the work platform). The arguments presented by
the commenters are summarized below, along with OSHA's response to
these comments and the Agency's reasoning in reaching a final
determination on the matter.
Several commenters (Exs. 2-9, 2-20, 2-21, 2-50, 2-53, 2-55, 2-64,
2-69, 2-367, 2-368, 2-390, and 2-476) argued for retention of 36 inches
as the minimum guardrail height. The reasons given by these commenters
were that ``no accident statistics justify changing the current range
existing in OSHA standards'' (Ex. 2-368), that 36 inches is adequate or
reasonable (Exs. 2-21, 2-53 and 2-69), that the height is practical,
feasible, and would not incur unmeasurable costs (Ex. 2-64), and that
36 inches is current industry practice (Exs. 2-367 and 2-476). Typical
of these comments was the comment of the SIA (Ex. 2-368):
Guardrails on scaffolds are designed as a perimeter warning for
workers confined to small working areas. Workers do not attain body
motion speeds and momentum that require the drastic changes
proposed.
Doctoral papers and NBS studies used as a basis for the
proposals do not deal with the ``real'' world. Dummies propelled
against a guardrail do not represent a true comparison of a human
being with sense and reflex ability.
Guardrails for scaffolds, whether they be horizontal systems or
crossbrace systems have historically been considered a perimeter
indication. Work is performed in localized areas where movement is
generally restricted from section to section. Workmen are not
subjected to the hazard of ``momentum'' created by body movement
over longer distances as in the case in peripheral railings or
balconies and other crowded or congested areas where body weight and
force may be accelerated * * *
It is apparent that guardrails of most manufacturers will fall
within the proposed 38-inches to 45-inches range. However, there are
many in the stream of commerce, and widely used throughout industry,
which will not. As an example, the GKN Kwikform scaffold system
utilizes a post with guardrail attachment points every 37\1/2\''.
This distance is based on the European standard spacing of one meter
[approximately 39 inches]. There is no justification for outlawing
the equipment which has been used safely for decades. It is more
practical to retain the 36-inches to 45-inches range permitted in
the various industry and ANSI standards.
The SSFI (Ex. 2-367) agreed with the SIA, stating as follows:
The majority of scaffold guardrail posts, manufactured in this
country since 1950, has been designed and manufactured to ANSI A10.8
Standard of 36'' to 42'' guardrail heights. The elimination of the
lower 36-inch limit would result in the requirement to scrap all
these posts and remanufacture new posts.
The cost to replace guardrail units would be very expensive to
the user. In 1983, we estimated that there were at least one million
guardrail units being used. Retrofit changes at that time were
estimated at $4 per unit or a total of $4,000,000. Replacement costs
at $10 per unit would equal $10 million.
In response to this group of commenters, OSHA notes that the
absence of accident statistics substantiating the need for higher
guardrails reflects on the general inadequacy of occupational injury
and illness recording and reporting systems but may well have little or
nothing to do with guardrail heights and their relationship with fall
hazards. It is OSHA's experience that few accident reports contain the
detail that would be necessary to differentiate between the relative
protectiveness of guardrail heights of 36 as opposed to 38 or 39
inches. In addition, although guardrails do function as perimeter
indicators, they also provide fall protection, and it is this aspect of
scaffold guardrails that is of concern in final rule paragraph
(g)(4)(ii). Further, although ``[d]ummies propelled against a
guardrail'' (Ex. 2-368) cannot precisely mimic the responses and
movement of real workers in the actual work environment, the
experiments dismissed by the SIA provide valuable information that
cannot be disregarded by OSHA or other safety professionals.
OSHA recognizes the merit of the SIA and SSFI arguments about
industry's use of scaffold components (e.g., posts) suitable for 36-
inch guardrails (Exs. 2-367 and 2-368), although the Agency also notes
that the $4 to $10 per scaffold unit cost for retrofit or replacement,
respectively, would not be prohibitive even for the smallest scaffold-
using business. Nevertheless, to respond to these concerns, the final
rule grandfathers those guardrails manufactured to meet the 36-inch
minimum height allowed by OSHA for many years and still accepted by
ANSI A10.8-1988. The Agency concludes that allowing the continued use
of these guardrails until they are replaced will eliminate any
potentially adverse impact of the final rule's determination as regards
minimum guardrail heights.
Many commenters (Exs. 2-12, 2-13, 2-29, 2-41, 2-54, 2-407, and Tr.
6/9/87, pp 116-121) share OSHA's concern, as stated in the preamble,
that a minimum guardrail height of 36 inches is insufficiently
protective. For example, one commenter (Ex. 2-407) stated:
[T]he guardrail height requirement should be set from 38-inches
to 45-inches with a midrail. Our experienced opinion has taught us
that 36-inches would be very unsafe. Especially for taller
person[s]. * * * As the industry has been set at 42'' for so many
years we feel that the 38'' to 45'' all inclusive would be
satisfactory to cover the 42'' which so many people would now have,
thus creating no additional expense.
Two other commenters (Exs. 2-29 and 2-41) also expressed concerns
about the adequacy of 36 inch high guardrails for tall employees, as
did Lawrence Stafford, a member of both the ANSI A10.8 Committee and
the SIA, who commented (Ex. 2-13)
I and many other members of S.I.A. do not consider 36-inches as
safe for all scaffold uses. Due to the narrow width of the platforms
on suspended scaffolds, the outboard sides should be protected by a
42-inch high guardrail.
Arguing in the same vein, a representative of OSHA's Advisory
Committee on Construction Safety and Health (June 9, 1987 meeting)
stated: ``I think, if anything, people are getting bigger, not smaller.
To leave something down at 36 inches only increases the hazard to the
fellow working on a suspended scaffold where he needs a much as he can
get * * *'' Another representative said that a 36-inch high guardrail
``strikes you in the wrong place * * * He goes over the rail or he
backs up to it while he's doing some work, it hits him at the wrong
point and he's gone.'' (Tr. 6/9/87, pp. 116-121).
Based on a review of the comments submitted on this issue, the
Agency's experience in enforcing this requirement over the years, and
OSHA's professional judgment, the final rule allows employers to
position scaffold guardrails in the range of 38 to 45-inches on
supported scaffolds, as proposed. This range is also consistent
[[Page 46072]]
with the guardrail criteria set in the revised standard (subpart M) for
Fall protection. However, OSHA recognizes that plank overlap is a
legitimate reason to accept a somewhat lower guardrail height on some
scaffolds. Thus, although the record indicates that most scaffolds on
the market fall within the 38- to 45-inch range (Ex. 2-368), some
scaffolds have been manufactured to meet the 36-inch lower guardrail
height limit accepted by ANSI. To allow the manufacturers of these
scaffolds the necessary time to redesign their systems, the Agency is
grandfathering 36-inch guardrail heights on all scaffolds manufactured
and installed before January 1, 2000. These scaffolds may continue to
be used throughout their normal service life, as long as they continue
to meet the other requirements of subpart L.
Final rule paragraph (g)(4)(iii), which is effectively identical to
proposed paragraph (e)(4)(iii), states that, when midrails, screens,
mesh, intermediate vertical members (such as balusters), solid panels,
or equivalent structural members are used, they are to be installed
between the top edge of the guardrail system and the scaffold platform.
This is essentially the same requirement as existing
Sec. 1926.451(a)(5), except that the existing language mentioned only
midrails and provided for the use of midrails ``when required.'' In the
final rule OSHA has revised the existing language to reflect the
variety of options available and to express the Agency's intent
clearly.
Final rule paragraphs (g)(4)(iv) through (vi) (proposed as
paragraphs (e)(4)(iv)-(vi)) specify the criteria necessary to ensure
that the midrails, screens, mesh, and baluster type protection required
by paragraph (g)(4)(iii) will be properly placed and effective.
Paragraph (g)(4)(iv) requires that midrails, when used, be installed at
a height midway between the top edge of the guardrail system and the
platform surface. Paragraph (g)(4)(v) requires that screens and mesh,
when used, extend from the top edge of the guardrail system to the
scaffold platform, and along the entire opening between the supports.
Paragraph (g)(4)(vi) requires that intermediate vertical members (such
as balusters or additional rails), when used, be not more than 19
inches (48 cm) apart.
The SSFI and SIA (Exs. 2-367 and 2-368) recommended the addition of
the word ``approximately'' to the midrail height required in paragraph
(iv). These commenters argued that, without the flexibility provided by
this word, the provision was unnecessarily restrictive and did not
properly address varying platform heights (such as where adjoining
platforms overlap) or the height variations allowed for toprails. OSHA
agrees that it is appropriate to allow for such variation, and the
final provision reflects this suggestion.
Paragraph (g)(4)(vii) of the final rule provides that toprails or
equivalent members be capable of withstanding, without failure, a force
applied in any downward or horizontal direction at any point along
their top edge of at least 100 pounds (445 n) for guardrail systems
installed on single-point adjustable suspension scaffolds and on two-
point adjustable suspension scaffolds, and at least 200 pounds (890 n)
for guardrail systems installed on all other scaffolds.
The strength criteria for guardrail systems on single-point
adjustable and two-point adjustable suspension scaffolds differ from
the criteria set for guardrails used on other types of scaffolds
because of the functions guardrails serve on these types of suspension
scaffolds. Fall protection on these suspension scaffolds is provided by
a combination of personal fall arrest systems (PFAS) and guardrails,
rather than by either guardrails or PFAS alone. Guardrails on single-
point adjustable and two-point adjustable suspension scaffolds
delineate the scaffold edge, restrain movement, provide handholds, and
prevent misstepping. A guardrail system can serve these functions
without having the strength that would be needed if the guardrails were
the primary means of providing fall protection. Therefore, OSHA has set
the minimum capacity for guardrail systems used on single-point and
two-point scaffolds at 100 pounds rather than at 200 pounds.
This is the same substantive requirement as was proposed in
paragraph (e)(4)(vii); however, the language has been modified as
discussed above to replace the proposed terms ``Type I'' and ``Type
II'' guardrails with the pertinent performance criteria. One commenter
(Ex. 2-44) recommended that the force requirements be changed to 100
pounds for Type I toprails and 80 pounds for Type II toprails. OSHA has
maintained the proposed strength requirements, i.e., 100 pounds, for
all toprails because the Agency believes that they are necessary to
prevent employees from breaking through toprails if they fall against
them.
Final rule paragraph (g)(4)(viii) provides that when the loads
specified in paragraph (g)(4)(vii) are applied in a downward direction,
the top edge may not drop below the height above the platform surface
prescribed in paragraph (g)(4)(ii). Proposed paragraph (e)(4)(viii) was
identical to the corresponding requirement in the final rule except
that the proposal limited deflection to 38 inches on supported
scaffolds (Type I guardrails) and 36 inches on suspended scaffolds
(Type II guardrails). The parallel final rule provision does not
contain the proposed guardrail designations, for the reasons discussed
above, and the provision also reflects minor editorial changes.
Paragraph (g)(4)(ix) of the final rule states that midrails,
screens, mesh, intermediate vertical members, solid panels, and
equivalent structural members must be capable of withstanding, without
failure, a force applied in any downward or horizontal direction at any
point along the midrail or other member of at least 75 pounds (333 n)
for guardrail systems with a minimum 100 pound toprail capacity, and at
least 150 pounds (666 n) for guardrail systems with a minimum 200 pound
toprail capacity. Except for the changes in guardrail system
terminology discussed above, this provision is the same as proposed
paragraph (e)(4)(ix).
The 150 pound force requirement is not specified in the existing
standard. However, the existing requirements (e.g.,
Sec. 1926.451(b)(15) et al.) require midrails to be made of 1 x 6-inch
lumber (or other material providing equivalent protection). The
existing standard also requires midrails to be not more than 8 feet
long (Sec. 1926.451(a)(5)), and to be made of a minimum 1,500 fiber
stress construction grade lumber (see Sec. 1926.451(a)(9)). On the
average, such wooden midrails can support loads up to approximately 160
pounds before breaking. Therefore, OSHA is replacing the specific
reference to 1 x 6-inch lumber with the performance criterion of 150
pounds force. Similarly, OSHA has adopted a performance criterion of 50
pounds for toeboards in final rule paragraph Sec. 1926.451(f)(3).
The only commenter (Ex. 2-44) on this issue recommended that the
proposed force requirements be changed to 75 pounds for Type I and 40
pounds for Type II midrails. OSHA has not made this change because the
Agency believes that the final rule's strength requirements for
midrails are necessary to prevent employees from breaking through
midrails or other intermediate members of the guardrail system. In
addition, OSHA has not maintained the distinction between Type I and
Type II midrails made in the proposal.
Final rule paragraph (g)(4)(x) (proposed paragraph (e)(4)(x))
provides that a separate guardrail section is not required on the ends
of suspension scaffolds when the scaffold's support system (stirrup) or
hoist prevents
[[Page 46073]]
passage of employees. One commenter (Ex. 2-8) suggested that OSHA
specify a maximum space of 10 inches between the hoist or stirrup and
the side guardrail or structure. Another commenter (Ex. 2-28) suggested
that the language of this paragraph be changed from ``does not allow
passage'' to ``does not allow normal passage without climbing over the
stirrup.'' OSHA has not made the suggested changes because this
requirement is clear as written.
Paragraph (g)(4)(xi) (proposed paragraph (e)(4)(xi)) of the final
rule requires that guardrail systems be so surfaced as to prevent
injury to an employee from punctures or lacerations, and to prevent the
snagging of clothing. This provision is consistent with
Sec. 1926.502(b)(6), which sets criteria for guardrails used in
construction, other than on scaffolds.
The language of the final rule is effectively identical to that in
the proposed rule, except that the proposed rule contained the words
``which could cause an employee to fall.'' OSHA used those words to
explain that one reason that guardrail systems should have smooth
surfaces is to prevent snagging of clothing. OSHA did not intend by
this language to limit protection to those situations where snagging
would actually result in a fall. OSHA realizes that other hazards, such
as exposure to falling objects, could arise if an employee's clothing
snagged on a guardrail surface. In the final rule, OSHA has revised the
proposed language accordingly.
The SSFI and SIA (Exs. 2-367 and 2-368) objected to the inclusion
of this provision in the final rule. Both commenters stated that the
provision would be ``impractical in the construction industry because
of the different types of equipment used,'' and would be
``unquestionably over-restrictive for the construction industry.'' The
SIA (Ex. 2-368) added ``As worded, even the standard guardrail posts
could be considered hazardous.'' OSHA believes that this existing
requirement is still needed and is promulgating the proposed provision
as editorially revised. The Agency does not intend this provision to be
interpreted to mean that guardrail system components have sanded or
finished surfaces. Instead, OSHA intends that such surfaces be free of
breaks and jagged edges that could cause cuts or lacerations, or snag
employee's clothes.
Paragraph (g)(4)(xii) of the final rule, which is effectively
identical to proposed paragraph (e)(4)(xii), requires that toprails and
midrails not be so long as to constitute a hazard. This is identical to
the corresponding provision in subpart M, (Fall protection)
Sec. 1926.502(b)(7), and is intended to protect employees from
projection hazards.
Paragraph (g)(4)(xiii) of the final rule, which is identical to
proposed paragraph (e)(4)(xiii), prohibits the use of steel banding and
plastic banding as toprails or midrails. Although such banding can
often withstand a 200 pound load, it can tear easily if twisted. In
addition, such banding often has sharp edges which can cut a hand if
seized. This is identical to the corresponding provision in subpart M
(Fall protection), Sec. 1926.502(b)(8).
Paragraph (g)(4)(xiv) of the final rule requires that guardrail
systems using manila, plastic or synthetic rope as rails be inspected
by a competent person as frequently as necessary to ensure that the
guardrails comply with the performance criteria in final rule
Sec. 1926.451(g). This provision has been added based on the response
to Hearing Notice Issue L-10.
Issue L-10 sought testimony and related information on an ACCSH
recommendation (Tr. 212-214, 6/9/87) that the Agency bar the use of
manila rope and plastic rope as toprails and midrails of guardrail
systems used on scaffolds. This recommendation reflected ACCSH's
concern that manila rope and plastic rope can lose strength quickly
when exposed to water and sun.
The SIA (Exs. 5a-16 and 10, Tr. 3/22/99, pp. 160-161) disagreed
with this view on the grounds that it should not be necessary to
restrict the type of material that can be used because other provisions
of the standard spell out system strength requirements for guardrails.
Another commenter (Exs. 5a-3 and 13) agreed, noting that, particularly
for short-term use, ``a rope is handy, adequate, and perfectly safe.''
This commenter stated that these ropes ``should not be barred from use
on scaffolds providing they are capable of supporting a 100-pound load
(Type II) or a 200-pound load (Type I) applied in any direction without
excessive deflection.''
Zurn Industries (Ex. 2-81) commented that ``plastic rope'' should
be defined, but did not provide such a definition. Zurn also stated
``[t]here are synthetic ropes made of plastic materials that do not sag
or lose strength when exposed to water or sun.'' This commenter also
suggested applying performance language to all materials used for
guardrails since future technology might provide more advanced types of
plastic rope.
After carefully considering the above comments and testimony, OSHA
believes that it is not necessary to prohibit the use of manila,
plastic or synthetic rope as guardrails on scaffolds. The Agency
realizes that these types of ropes can deteriorate over time from
environmental exposure. However, the Agency also realizes that such
ropes can have a useful lifespan before significant deterioration
occurs. Consequently, OSHA is promulgating final rule
Sec. 1926.451(g)(4)(xiv), which allows the use of plastic, manila or
synthetic rope only on condition that such ropes be inspected as often
as necessary to ensure their integrity. This provision is consistent
with the approach taken in Sec. 1926.502(b)(16), which sets generic
performance criteria for guardrails used in construction.
Paragraph (g)(4)(xv) of the final rule permits the use of
crossbracing in lieu of either a midrail or a toprail when certain
criteria are met. This provision is based on responses to NPRM Issue 13
and the March 29, 1993, reopening of the record. In particular,
crossbracing would be accepted in lieu of a toprail when the crossing
point is between 38 and 48 inches above the work surface. Also,
crossbracing would be accepted in lieu of a midrail when the crossing
point is between 20 and 30 inches above the work surface. In addition,
the end points of each upright must be no more than 48 inches apart,
which will reduce the slope of the crossbracing and result in a surface
that is similar to that of a standard guardrail.
The Agency received over 30 comments in response to Issue 13 and
the March, 1993 reopening of the record on the issue of the use of
crossbracing in lieu of guardrails (Exs. 2-13, 2-14, 2-20, 2-22, 2-26,
2-29, 2-30, 2-37, 2-43, 2-54, 2-55, 2-128, 2-330, 2-367, 2-368, 2-390,
2-476, 34-1, 34-9, 34-10, 34-11, 34-12, 34-15, 34-17, 34-19, 34-22, 34-
29, 34-32, 34-34, 34-35, 34-37, 34-39, 34-43, 34-46, and Tr. 6/9/87,
pp. 121-126). These comments are discussed below,
Issue 13 of the NPRM sought comments concerning whether OSHA should
accept crossbracing on intermediate levels of supported scaffolds as an
alternative to the existing and proposed rules requiring guardrail
systems on such levels. The Issue raised the question of whether
crossbraces are as effective as guardrail-type systems in preventing
falls, and asked for comments on two sets of provisions that had been
developed by the SIA and other interested industry groups.
Issue 13 presented the first three alternatives as a group
(hereafter Items 1(a)-(c)). Item 1(a) would have allowed crossbracing
in lieu of a midrail if the crossing point was at or between 20 and
[[Page 46074]]
32 inches above the work surface. Item 1(b) provided that crossbracing
would be allowed in lieu of both midrail and toprail if the crossing
point was at or between 30 and 48 inches above the work surface and the
end points of the uprights were 54 inches, or less, apart. Item 1(c)
would have prohibited the use of crossbracing in lieu of a toprail or
midrail on the top level of a scaffold (Issue 13 repeated this
suggested provision as Item 2(c)).
Issue 13 also presented a second set of alternatives for
crossbracing (hereafter Items 2(a)-(d)). Item 2(a) provided that
crossbracing would be allowed in lieu of a toprail if the crossing
point was at or between 39 and 49 inches above the work surface and the
endpoints of the uprights were 54 inches, or less, apart. Item 2(b)
provided that crossbracing would be allowed in lieu of a midrail if the
crossing point was at or between 20 inches and 30 inches above the
working surface. Item 2(d) would prohibit the use of crossbracing in
lieu of both the toprail and midrail on the same scaffold level at the
same time.
Commenters to Issue 13 were split into two groups: those supporting
(Exs. 2-14, 2-20, 2-22, 2-26, 2-30, 2-53, 2-55, 2-367, 2-368, 2-390,
and 2-476) and those rejecting (Exs. 2-13, 2-29, 2-37, 2-43, 2-54, 2-
128, and ACCSH) the use of crossbracing in lieu of guardrails.
The ACCSH (Tr. 6/9/87, pp. 121-129) and six commenters (Exs. 2-13,
2-29, 2-37, 2-43, 2-54 and 2-128) opposed OSHA recognizing crossbracing
as a substitute for a standard guardrail. One commenter (Ex.2-13 )
stated ``that there is no substitute for the protection afforded by a
constant-height guardrail''. The same commenter added that ``there is
no industry standard to allow a substitution in that the OSHA standards
have required guardrail systems since 1971''.
On the other hand, those commenters favoring crossbracing argued
that crossbracing should be allowed in lieu of the entire guardrail
system (Exs. 2-14, 2-20, 2-26, 2-30, 2-55, 2-367, 2-368, 2-390, and 2-
476), or that crossbracing should be permitted on intermediate levels
(Ex. 2-53), or that it should be permitted as a midrail only if the
midpoint of the ``X'' was 20 to 32 inches from the platform (Ex. 2-22).
Specifically, commenters in the group favoring crossbracing argued
that requiring guardrails in all situations could result in structural
instability (Ex. 2-14), was impractical, increased the likelihood of
accidents, could cause problems when attempting to attach guardrails to
the scaffold frame, and might raise issues of economic feasibility (Ex.
2-368). Some of these commenters also argued that available statistics
did not support retention of the existing rule's prohibition against
the use of crossbracing in lieu of guardrails (Exs. 2-20, 2-55, 2-367,
2-368, and 2-390).
For example, one commenter (Ex. 2-14) stated:
If cross braces and guardrail cannot be placed on the same
studs, and only toprails and midrails are used to connect a run of
scaffold frames other than the top run, a very hazardous structural
situation is created. This is due to the lack of triangulation which
crossbraces provide.
The SIA (Ex. 2-368) argued that:
Each time workers completed one level they would have to remove
the guardrail posts and rails, install frames and cross braces,
plank the next level, install guardrail posts and rails and repeat
the procedure at each level.
The increased work would create a greater possibility of
accident than that which it proposes to prevent.
The SIA also commented, argued that:
It is impractical and economically unfeasible to require
manufacturers to call in all their scaffolds for refurbishing. There
is no way the owners of scaffolds would comply nor any way the
manufacturer could force them to do so. The result would be a far
greater hazard due to alteration of the scaffold frames by persons
not qualified to perform the delicate welding required on steel
scaffold. It is further impossible when you consider the fact that
there are hundreds of thousands of separate owners of scaffold
frames manufactured by numerous manufacturers, many of which are no
longer in business.
The AGC (Exs. 2-20, 2-55, and 2-390) stated that crossbracing can
be used as an effective guardrail, because ``studies do not reflect
actual field conditions and accident statistics do not reflect the need
for the existing standard.'' OSHA notes, however, that inadequate
accident statistics and that lack of detailed annotation about the
details of accidents that are reported should not be taken as evidence
that no relationship exists.
Based on its review of the above-discussed comments, OSHA decided
that more information was needed in order to determine if the Agency
should allow the use of crossbracing in lieu of guardrail top rails or
midrails. Accordingly, on March 29, 1993, OSHA reopened the public
record on subpart L (58 FR 16509) for additional input. In particular,
the Agency requested comments regarding the extent to which
supplemental rail systems could be used with crossbraces to meet the
guardrail requirements of subpart L.
The commenters to the Reopening of the record either agreed with or
opposed the use of crossbracing in lieu of a guardrail in about the
same proportions as the earlier commenters. Their comments, which are
closely related to those addressed by the earlier commenters on this
issue, are only briefly summarized below:
--Those opposed to the use of crossbracing (Exs. 34-1, 34-11, 34-19,
34-22, 34-29, 34-34, and 34-35) argued that crossbraces would not
provide protection equivalent to that provided by standard guardrails,
because crossbracing lacks the uniform height and consistent spacing
between toprails and midrails that are found in guardrail systems and
are necessary for adequate protection (Ex. 34-11); because there are
variations in attachment heights, distances between crossmembers, and
the strength of the attachment points where crossbracing is used (Ex.
34-34); and because the use of crossbraces may promote shortcuts in
scaffold erection since employers might fail to measure the points of
the crossbracing or to add toeboards (Ex. 34-19). In addition, one
commenter stated that crossbraces should be supplemented by midrails
and toprails because employees may fall through the triangular void on
either side of the intersection of the braces, and added that
crossbraces may give a false sense of security (Ex. 34-35), and another
(Ex. 34-22) stated that commercial scaffolds are all capable of being
fitted with conventional guardrails, and that crossbraces can, at best,
only be used to replace either the toprail or midrail, not both.
--Those supporting the use of crossbracing in lieu of guardrails
(midrail or toprail) urged OSHA to adopt certain height requirements
for the crossing points of the crossbracing. For example, five
commenters (Exs. 34-9, 34-10, 34-12, 34-17, 34-37) stated that
crossbracing could be substituted for a midrail as the crossing point
of the brace is between 20 and 31 inches above the work surface, while
others argued that crossbracing could be used in lieu of a toprail or
midrail if the crossing point fell in the range of 30 to 48 inches
above the working surface. Another group of participants (Exs. 34-9,
34-10, 34-12, and 34-17) were of the opinion that crossbracing
substituting for a midrail should have a crossing point in the 20- to
30-inch range. A large number of commenters (Exs. 34-9, 34-10, 34- 12,
34-17, 34-32, 34-37, and 34-39) stated that end points of the
crossbraces must be no more than 54 inches apart.
[[Page 46075]]
Another group of commenters (Exs. 34-5, 34-9, 34-10, 34-12, 34-17,
34-22, and 34-29) provided information on supplemental rail systems,
such as those produced by Waco, Safway or Nail. These commenters stated
that such systems are feasible and would provide protection equivalent
to guardrails that comply with proposed subpart L in certain
situations.
Donald Nail (Ex. 34-15) commented as follows:
* * * I have devised a way to enhance scaffold safety. The
safety rail which I invented can be conveniently attached to
scaffold crossbraces, thus eliminating the excuses of those
employers and employees who simply do not want to put them up.
This invention is not currently on the market due to resistance
from the scaffold and construction industries. If OSHA regulations
were changed to require a guardrail with scaffolding, employer
compliance would follow without undue economic hardship. The average
cost would be about $5 (plus the rail) per frame as opposed to
current systems averaging $30.
The basic concept for my automatic guard rail is that you cannot
erect a welded-frame scaffold without crossbraces. The automatic
guardrail would be permanently attached to the crossbraces with a
slide ring on each end of the rail . . . The guard rail will fold up
with the crossbraces when they are taken down for shipping or
storage. The crossbraces are easier and quicker to install with the
guard rail attached than without, not to mention safer. If the guard
rail is permanently attached to the crossbraces the workmen will
have installed the guard rails automatically, thereby helping to
reduce numerous fatalities and thousands of scaffold injuries each
year.
However, commenters opposed to the use of supplemental rail systems
(Exs. 34-32, 34-37, and 34-39) argued that the Safway panel can only be
installed on walk-through frames that have attachment members on both
sides. They added that these systems were designed to be used in cases
where crossbracing is not required in every bay.
SIA (Ex. 34-37) commented that the Waco system has not been
accepted by industry because: (a) It can only be used on a specific
type scaffold frame; (b) It increases the number of pieces three-fold
because it also requires two additional rails; (c) It significantly
increases the dead load on the scaffold; (d) It has not proved to be
economically feasible. The commenter added that Patent Scaffolding Co.
has had a similar device consisting of four pieces for 10 years, but
that it has not been widely used for the same reasons.
In addition, the SIA contended that the Nails Safety Rails system
is not feasible because:
(a) It is a proprietary system which cannot be used universally.
(b) It cannot be used with angle braces which account for 60% of
most inventory.
(c) When attached to the crossbrace it becomes permanent (since
it is riveted on) and therefore, by its very nature must be used
(with the crossbrace) where it would not be required--thus adding
considerable more dead load to the scaffold.
(d) It requires another inventory item not usually included in
stock.
(e) It requires extra attachments to the scaffold frame.
(f) It creates costly maintenance problems when plaster and
cement hinder sliding the rail.
(g) It is not cost effective.
The Agency finds that the supplemental railings discussed above can
be used as guardrails in some situations. However, these supplemental
systems are not compatible with all scaffolds, and will thus not
address the guardrail vs. crossbracing issue. In addition, based on the
determination, discussed above, that crossbracing can be used safely in
lieu of either a midrail or a toprail, but not both, the Agency finds
no reason to mandate the use of these supplemental railings. Employers
may still use these railing in situations where they are appropriate to
protect employees working on scaffolds from fall hazards.
After carefully reviewing the extensive record on this issue, the
Agency has determined that it is appropriate to allow crossbracing in
lieu of a midrail or a toprail (but not both). The crossing point
heights and crossbrace endpoint distance spelled out in the final rule
are based on a combination of those raised in Issue 13 of the NPRM and
those specified in the California code and reflect OSHA's evaluation of
the record as a whole.
OSHA disagrees that crossbracing can be used in lieu of both the
midrail and the toprail of a standard guardrail system. The principal
reasons for this determination are that the voids on each side of the
intersection of the crossbraces present a serious fall hazard to
employees working on scaffolds, and that the uneven height and spacing
of crossbraces also contribute to the fall hazard. For example, if OSHA
permitted crossbracing in lieu of both a toprail and a midrail, the
voids below the crossing point of the crossbrace could be as high as 48
inches. This would be inconsistent with good safety practice and with
subpart M of this part (Fall protection), which requires that openings
in walls or other vertical surfaces not exceed 30 inches in height
unless a guardrail is installed. In addition, Review Commission
decisions (see, for example, 10 OSHRC 1937 and 7 OSHRC 1951) have
consistently upheld OSHA's position that crossbracing is not equivalent
to a guardrail in the degree of protection provided. Support for the
position taken in the final rule also comes from California, where the
State Code initially allowed the use of crossbracing in lieu of a
guardrail system but was changed in 1976 to limit the use of
crossbracing as only a midrail or a toprail, but not both. A review of
California's experience shows that permitting the use of crossbracing
in lieu of either a midrail or a toprail has not compromised employee
safety. Washington State and Arizona both allow such use of
crossbracing; OSHA notes that these three states together account for
well over 10 percent of all U.S. construction work. In addition,
specifics of the California code agree with those in the final rule.
For example, California accepts crossbracing as a toprail if the
intersection of the ``X'' occurs at 45 inches (+/-3 inches). Issue 13
suggested a range of 39 to 49 inches for the height of the crossing
point, and the final rule accepts a range of 38 to 48 inches to reflect
the lower limit of guardrail height permitted by this final subpart L,
and the upper limit permitted by the California code.
In addition, the final rule specifies that the end points of each
upright be no more than 48 inches apart, not 54 inches as suggested by
many commenters and raised in NPRM Issue 13. This spacing (48 inches)
is consistent with the California code and will reduce the slope of the
crossbracing and result in a flatter surface that is more consistent
with that of a standard guardrail, and will provide equivalent
protection.
The Agency has concluded that crossbracing where the crossing point
is between 20 and 30 inches can serve safely as a midrail since the use
of a standard top rail will provide the uniform height that the Agency
has determined is necessary, while the use of a toe board will limit
the size of any openings (voids) on either side of the crossing point.
Similarly, OSHA believes that where the crossing point occurs in
the 38- to 48-inch range the crossbracing must be supplemented by a
midrail. Otherwise, an opening as high as 48 inches could occur,
allowing an employee to fall. These conditions would also occur if
crossbracing were permitted to be used in lieu of a complete standard
guardrail. Accordingly, the final rule contains provisions allowing use
of crossbraces as a substitute for either the midrail or toprail, but
not both, providing that the crossing point and end point distances
specified in the final rule are observed.
[[Page 46076]]
Paragraph 1926.451(h). Falling object protection.
This paragraph addresses the protection of employees from scaffold-
related falling object hazards. Paragraph (h)(1) of the final rule
provides that employees working on scaffolds wear hardhats and be
protected from falling hand tools, debris, and other small objects
through the installation of toeboards, screens, or guardrail systems or
through the erection of debris nets, catch platforms, or canopy
structures that deflect falling objects. In addition, when the falling
objects to which employees on scaffolds may be exposed are too large,
heavy or massive to be contained or deflected by any of the above-
listed measures, the employer must protect affected employees by
placing any such potential falling objects away from the edge of a
surface from which they might fall and must secure those materials as
necessary to prevent their falling.
This provision is similar to proposed paragraph (f)(1), which was
based on existing Secs. 1926.451(a)(16) and (h)(13). OSHA has added the
phrase ``hand tools, debris, and other small'' to describe the type and
size of objects that OSHA expects would be handled by toeboards,
screens, guardrails, canopies, debris nets and catch platforms. In
addition, the Agency has added language which requires that employers
place materials away from an edge over which they might fall and secure
those objects as necessary to prevent their falling, if those materials
are so large, heavy or massive that the above-listed measures would not
contain or deflect them. The changes that have been made to this
requirement since the proposal are based on comments received from the
SSFI and the SIA (Exs. 2-367 and 2-368) indicating that ``compressors,
marble, pipe, large bolts, etc. could be potentially falling objects''
and that it is unreasonable to require guarding against such large
objects.
OSHA agrees that the protective measures required by the proposed
paragraph would not be adequate to withstand large objects. For
example, a slab of marble facing would smash through screens or
guardrails if it had not been properly stored and retained. In fact, an
object of this mass would probably crash through a debris net or even a
catch platform or protective canopy. As provided by the final rule, the
appropriate way to protect affected employees from such large items is
to locate those items away from the edge and to secure them to keep
them from falling.
Because objects falling from scaffolds may injure employees working
below, final rule paragraph (h)(2) requires employers to protect
affected employees from that hazard and sets forth several alternative
means by which employers can provide the required protection. The
provisions of proposed paragraph (f)(2) were identical, except that
debris nets and catch platforms have been added to the final rule,
because, based on review of the rulemaking record, OSHA considers such
measures to be acceptable alternatives.
Paragraph (h)(2)(i) provides for the use of barricades on lower
levels to exclude employees from areas where falling objects might
land. Compliance with this new provision will enable employers to
eliminate employee exposure to the hazard.
Under paragraph (h)(2)(ii), employers would be required to provide
toeboards along the edge of platforms more than ten feet above lower
levels for a distance sufficient to protect workers below, except that
on float (ship) scaffolds, an edging of \3/4\ inch x 1\1/2\ inch
wood, or a material with equivalent strength, may be used in lieu of a
toeboard. This provision differs from existing Sec. 1926.451(a)(4),
which requires toeboards to be erected along the entire length of all
open sides and ends of all scaffolds more than 10 feet high. The final
rule, like proposed paragraph (f)(2)(ii), requires toeboards only where
needed to protect employees below from falling object hazards.
For example, on a long scaffold where employees are working on the
ground near one end of the scaffold, compliance with this provision
would require the scaffold to have a toeboard at the end over the
employees below, but not at the other end. This would be the case
regardless of the height of the scaffold work platform. This change
recognizes that toeboards and equivalent members are for the protection
of employees below. Accordingly, if no employees are exposed, no
protective measures are necessary.
Paragraph (h)(2)(iii) of the final rule provides, as an
alternative, for erection of paneling or screening in cases where tools
or other materials are piled to a height higher than the top edge of a
toeboard. The panel or screen must extend from the toeboard (or
platform) to the top of the guardrail and be erected for a distance
sufficient to protect employees below. In addition, the panel or screen
would need to be capable of withstanding, without failure, a force of
at least 150 pounds, applied in any downward or outward direction at
any point along the screen (to comply with paragraph (g)(4)(ix)). This
provision is effectively identical to proposed paragraph (f)(2)(iii).
The proposed rule referenced the proposed Sec. 1926.502 criteria for
screens, while the final rule directly incorporates the applicable
strength requirement from Sec. 1926.502(b)(5), Fall protection (subpart
M). OSHA believes that this revision will facilitate compliance by
eliminating the need for employers to look up a cross reference.
Paragraph (h)(2)(iv) of the final rule allows employers to protect
employees from falling objects through the installation of a guardrail
system which complies with Sec. 1926.451(g)(4) and which has openings
small enough to reject passage of potential falling objects. This
provision is identical to proposed paragraph (f)(2)(iv).
Paragraph (h)(2)(v) of the final rule provides that employers can
protect employees working below scaffolds from falling objects through
the installation of debris nets, catch platforms, or canopies that have
sufficient strength to withstand the impact forces of potential falling
objects.
In contrast to final rule paragraph (h)(2)(v), proposed paragraph
(f)(2)(v) provided only for the use of a canopy structure. OSHA has
added debris nets and catch platforms to this provision in response to
the statement by Bristol Steel (Ex. 5a-3) that debris nets or catch
platforms immediately below a scaffold could be more protective than a
canopy many feet below. The Agency agrees that properly installed
debris nets and catch platforms in place immediately below a scaffold
will stop objects from falling closer to the source, and will lessen
the possibility that these falling objects will pick up momentum and
bounce off the canopy, injuring workers some distance from the area
below the scaffold.
Hearing Notice Issue L-13 sought testimony and comments on a
suggestion by the ACCSH (Tr. 6/9/87, 214-15) that proposed
Sec. 1926.451(f)(2)(v) specify nine feet as the proper height for the
placement of a canopy. The ACCSH noted that the proposed requirement
did not specify a height for canopy placement. According to the ACCSH,
a canopy set at 15 or 20 feet would not protect employees below.
However, the Advisory Committee did not provide a supporting rationale
for its position.
Both the SIA (Exs. 10 and 5a-16, and Tr. 3/22/88, pp. 162-163) and
SSFI (Ex. 5a-19) supported the placement of the canopy at a height of
10 feet. The SIA pointed out that standard scaffold frames are six-feet
high and adding a three-foot frame would raise the canopy top,
including the plank, to a height of
[[Page 46077]]
almost 10 feet. The SIA suggested that OSHA specify a ``maximum''
distance of 10 feet, noting that the proposed standard would not have
allowed for any variation to accommodate these standard frames. The
SSFI's comment stated that canopies ``should be erected no greater than
10 feet above the work surface'' and that because the intent of this
requirement was to provide employee protection from small falling
objects and/or light debris, ``the term `reasonable' should be included
within the definition.'' In addition, the SSFI asked what anticipated
impact forces such canopies would be required to withstand.
The National Chimney & Cooling Tower Association (Ex. 2-593)
indicated that no height restriction was appropriate for canopies. The
commenter stated that restricting the height would severely hamper
equipment access. Bristol Steel (Ex. 5a-3) supported allowing maximum
flexibility for designing various types of falling object protection
for varying situations. This commenter stated that there should be no
limitation on canopy height as long as the canopy functions as
intended.
After carefully considering the comments and testimony received in
response to this issue, OSHA believes that specifying a maximum height
for canopy placement could unnecessarily restrict the use of equipment.
In addition, the Agency believes that the use of performance-oriented
language, requiring that canopies be strong enough to withstand the
impact forces of potential falling objects, will ensure employee safety
and at the same time provide the flexibility necessary to respond
adequately to advances in technology as well as unusual or changing
work-site conditions. The employer is responsible for determining the
maximum size of potential falling objects and providing the appropriate
protection.
Final rule paragraph (h)(3) sets criteria for the use of canopies.
Paragraph (h)(3)(i) of the final rule, which is identical to proposed
paragraph (f)(1)(i), requires that canopies be installed between the
falling object hazard and the employees. Paragraph (h)(3)(ii) of the
final rule, which is identical to proposed paragraph (f)(1)(ii),
requires the use of additional independent support lines to support the
scaffold in the event of suspension support rope failure, in cases
where canopies are used for falling object protection on suspended
scaffolds. The reason for this requirement, as stated in the discussion
of final rule paragraph (g)(3), is that in the event of a suspension
rope failure, the additional lines would keep the scaffold from
falling.
Paragraph (h)(3)(iii) of the final rule, which is identical to
proposed paragraph (f)(1)(iii), requires that independent support lines
and suspension ropes not be attached to the same point of anchorage.
This new provision will prevent the loss of the backup safety systems
in the event of suspension rope anchorage failure.
Final rule paragraph (h)(4) sets strength criteria for toeboards.
Paragraph (h)(4)(i), which is a new requirement, requires that
toeboards be capable of withstanding, without failure, a force of at
least 50 pounds applied in any downward or horizontal direction at any
point along the toeboard. This provision contains a note which
indicates that toeboards built in accordance with Appendix A of subpart
L will be deemed to comply with the standard. This provision, which is
consistent with the corresponding requirement in OSHA's Fall Protection
standard, Sec. 1926.502(j)(2) (subpart M), is identical to proposed
paragraph (f)(3)(i).
Final rule paragraph (h)(4)(ii) sets forth the construction
requirements for toeboards. This provision requires that toeboards be
at least three and one-half inches high, fastened securely in place,
and have not more than \1/4\-inch clearance above the walking/working
surface. In addition, toeboards must be solid or have openings no
greater than one inch in the greatest dimension. This provision, which
is consistent with the corresponding requirement of the Fall Protection
standard, Sec. 1926.502(j)(3) (subpart M), is identical to proposed
paragraph (f)(3)(ii), except as discussed below.
OSHA received one comment on proposed paragraph (f)(3)(ii). That
commenter (Ex. 2-29) recommended a maximum space of \1/4\-inch between
the lower edge of the toeboard and the platform instead of the proposed
\1/2\-inch on the grounds that ``many small tools and fastener
materials can pass through a \1/2\-inch opening.'' OSHA agrees that
reducing this opening will enhance employee protection and has changed
the language of the final rule accordingly.
Other Issues Related to Sec. 1926.451
Issue L-7 of the hearing notice solicited testimony and related
information on the extent to which proposed Sec. 1926.451 (``General
requirements'') adequately covers smokestack hoist scaffolds. The
Agency also requested testimony and information on stack hoist hazards
not addressed by the general requirements, and explained that the issue
was being raised in light of ongoing efforts to update ANSI standard
A10.22, Safety Requirements for Rope Guided and Non-Guided Workmen's
Hoists. OSHA noted that the final rule might need to include provisions
to address the hazards unique to stack hoist scaffolds. However,
because stack hoist scaffolds are included in the definitions of
``scaffold'' and ``suspension scaffold'' used in the scaffold rules,
OSHA concludes that the final rule does not need to include specific
coverage for stack hoist scaffolds. OSHA notes that, since the
proposal, the ANSI A10.22-1977 standard for stack hoist scaffolds has
been rescinded and has not been replaced.
Sec. 1926.452 Additional Requirements Applicable to Specific Types of
Scaffolds
Section 1926.452 of the final rule contains requirements that
supplement the requirements of Sec. 1926.451 with regard to particular
types of scaffolds. The identified scaffolds have unique features which
require specific attention. This approach is consistent with that taken
in existing Secs. 1926.451 (b) through (y), which set out additional
provisions for specific types of scaffolds.
OSHA received comments (Exs. 2-13 and 2-23) which suggested that
specific scaffold design criteria and fall protection requirements be
added to proposed Sec. 1926.452 (particularly to proposed paragraphs
(i), (l), (m), (q), (r), (s), (t), (u) and (v)). OSHA has determined
that compliance with the performance-oriented provisions of final rule
Secs. 1926.451 and 1926.452, taken together, will provide adequate
protection for employees working on scaffolds. Further, the Agency
believes that the specification language suggested by the commenters
would limit innovation and impose unreasonable burdens on employers.
As discussed in the preamble to the proposed rule (51 FR 42691-6),
many existing Sec. 1926.451 requirements are not being carried forward
in final rule Sec. 1925.452 because the topics they address (capacity,
construction, access, fall protection and falling object protection)
are covered by provisions in final rule Sec. 1926.451. The provisions
being reordered are presented in Table 1, which shows the requirement
in OSHA's existing rule and the corresponding provision in the final
rule being published today.
[[Page 46078]]
Table 1.--Provisions Being Reordered in the Final Rule
----------------------------------------------------------------------------------------------------------------
Existing paragraph Final rule paragraph
----------------------------------------------------------------------------------------------------------------
Sec. 1926.451(b)(1)..................... Sec. 1926.451(c)(3), (d)(1)
Sec. 1926.451(b)(3)..................... Sec. 1926.451(b)(3)
Sec. 1926.451(b)(4)..................... Sec. 1926.451(c)(2)
Sec. 1926.451(b)(6)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(b)(8)..................... Sec. 1926.451(d)(1)
Sec. 1926.451(b)(11).................... Sec. 1926.451(b)(1)
Sec. 1926.451(b)(12).................... Sec. 1926.451(b)(4), (6) and Sec. 1926.451(a)(1)
Sec. 1926.451(b)(13).................... Sec. 1926.451(b)(7)
Sec. 1926.451(b)(15).................... Sec. 1926.451(g)
Tables L-4 through L-9................... Sec. 1926.451(a)(1) and (g)
Sec. 1926.451(c)(1)..................... Sec. 1926.451(a)(1) and (c)(1)
Sec. 1926.451(c)(2)..................... Sec. 1926.451(a)(1) and (c)(1)
Sec. 1926.451(c)(3)..................... Sec. 1926.451(a)(1) and (c)(1)
Sec. 1926.451(c)(5)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(c)(6)..................... Sec. 1926.451(d)(1)
Sec. 1926.451(c)(7) [last sentence]..... Sec. 1926.451(a)(1)
Sec. 1926.451(c)(12).................... Sec. 1926.451(c)(2)
Sec. 1926.451(c)(13).................... Sec. 1926.451(g)
Tables L-10 through L-12................. Sec. 1926.451(a)(1)
Sec. 1926.451(d)(1)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(d)(4)..................... Sec. 1926.451(b)(15)
Sec. 1926.451(d)(7)..................... Sec. 1926.451(b)(14)
Sec. 1926.451(d)(8)..................... Sec. 1926.451(a)(1) and Appendix A
Sec. 1926.451(d)(10).................... Sec. 1926.451(g)
Sec. 1926.451(q)(2)..................... Sec. 1926.451(b)(1)
Sec. 1926.451(q)(3)..................... Sec. 1926.451(e)
Sec. 1926.451(q)(4)..................... Sec. 1926.451(g)
Sec. 1926.451(n)(1)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(n)(2)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(n)(5)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(n)(7)..................... Sec. 1926.451(c)(3)
Table 15................................. Sec. 1926.451(a)(1)
Sec. 1926.451(o)(2)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(o)(3)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(o)(6)..................... Sec. 1926.451(f)(5)
Sec. 1926.451(o)(7)..................... Sec. 1926.451(g)
Table 16................................. Sec. 1926.451(a)(1)
Sec. 1926.451(m)(1)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(m)(3)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(m)(4)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(m)(5)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(b)(4)
Sec. 1926.451(b)(5)
Sec. 1926.451(m)(6)..................... Sec. 1926.451(g)
Sec. 1926.451(x)(1)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(x)(2)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(b)(4)
Sec. 1926.451(b)(5)
Sec. 1926.451(x)(3)..................... Sec. 1926.451(f)(2)
Sec. 1926.451(x)(4)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(b)(1)
Sec. 1926.451(b)(4)
Sec. 1926.451(b)(5)
Sec. 1926.451(x)(5)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(b)(4)
Sec. 1926.451(b)(5)
Sec. 1926.451(g)
Sec. 1926.451(x)(6)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(b)(4)
Sec. 1926.451(b)(5)
Sec. 1926.451(g)
Tables L-17, 18 and 19................... Sec. 1926.451(a)(1)
Sec. 1926.451(g)
Sec. 1926.451(g)(1) (in part)........... Sec. 1926.451(a)(1)
Sec. 1926.451(g)(4)..................... Sec. 1926.451(b)(3)
Sec. 1926.452(i)(8)
Sec. 1926.451(g)(5)..................... Sec. 1926.451(g)
Table L-13............................... Sec. 1926.451(a)(1)
Sec. 1926.451(y)(1)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(f)(2)
Sec. 1926.451(y)(3)..................... Sec. 1926.451(b)(1)
Sec. 1926.451(y)(4) (i) and (ii) (also Sec. 1926.451(a)(1)
(iii) in part).
[[Page 46079]]
Sec. 1926.451(y)(5) (also (y)(6) and Sec. 1926.451(c)(3)
(y)(7) in part).
Sec. 1926.451(y)(9)..................... Sec. 1926.451(e)
Sec. 1926.451(y)(10).................... Sec. 1926.451(a)
Sec. 1926.451(y)(11).................... Sec. 1926.451(g)
Sec. 1926.451(s)(5)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(b)(5)
Sec. 1926.451(s)(6)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(f)(2)
Sec. 1926.451(t)(3)..................... Sec. 1926.451(g)
Sec. 1926.451(t)(4)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(f)(2)
Sec. 1926.451(k)(1)..................... Sec. 1926.451(d)(13)
Sec. 1926.451(k)(2)..................... Sec. 1926.451(d)(14)
Sec. 1926.451(k)(3)..................... Sec. 1926.451(d)(15)
Sec. 1926.451(k)(4)..................... Sec. 1926.451(d)(16)
Sec. 1926.451(k)(5)..................... Sec. 1926.451(f)(3)
Sec. 1926.451(k)(8)..................... Sec. 1926.451(d)(2) through (d)(16)
Sec. 1926.451(k)(9)..................... Sec. 1926.451(g)
Sec. 1926.451(k)(10).................... Sec. 1926.451
Sec. 1926.451(l)(4)..................... Sec. 1926.451(g)
Sec. 1926.451(l)(6)..................... Sec. 1926.451(d)(5)
Sec. 1926.451(h)(1)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(f)(2)
Sec. 1926.451(h)(2)..................... Sec. 1926.451(d)(13)
Sec. 1926.451(h)(3)..................... Sec. 1926.451(a)(2)
Sec. 1926.451(h)(4)..................... Sec. 1926.451(d)(4)
Sec. 1926.451(h)(5)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(h)(6)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(d)(3)(i)
Sec. 1926.451(h)(7)..................... Sec. 1926.451(d)(4)(iii)
Sec. 1926.451(h)(8)..................... Sec. 1926.451(d)(4)(i)
Sec. 1926.451(h)(9)..................... Sec. 1926.451(d)(2)
Sec. 1926.451(h)(10).................... Sec. 1926.451(d)(9)
Sec. 1926.451(d)(7)
Sec. 1926.451(h)(11).................... Sec. 1926.451(d)(4)(iv)
Sec. 1926.451(h)(12).................... Sec. 1926.451(a)(1)
Sec. 1926.451(i)(2)..................... Sec. 1926.451(g)
Sec. 1926.451(i)(9)..................... Sec. 1926.451(d)(18)
Sec. 1926.451(j)(1)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(f)(2)
Sec. 1926.451(j)(2)..................... Sec. 1926.451(d)(13)
Sec. 1926.451(j)(3)..................... Sec. 1926.451(b)(4)
Sec. 1926.451(b)(5)
Sec. 1926.451(j)(4)..................... Sec. 1926.451(d)(4)
Sec. 1926.451(d)(5)
Sec. 1926.451(j)(5)..................... Sec. 1926.451(d)(4)(iii)
Sec. 1926.451(d)(3)
Sec. 1926.451(d)(4)(i)
Sec. 1926.451(j)(6)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(a)(2)
Sec. 1926.451(j)(7)..................... Sec. 1926.451(d)(9)
Sec. 1926.451(d)(7)
Sec. 1926.451(j)(8)..................... Sec. 1926.452(q)(1)
Sec. 1926.452(q)(2)
Sec. 1926.451(j)(9)..................... Sec. 1926.451(g)
Sec. 1926.451(w)(1)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(f)(2)
Sec. 1926.451(w)(2)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(w)(4)..................... Sec. 1926.451(g)
Sec. 1926.451(w)(5)..................... Sec. 1926.451(a)(2)
Sec. 1926.451(f)(4)
Sec. 1926.451(w)(6)..................... Sec. 1926.451(g)
Sec. 1926.451(r)(2)..................... Sec. 1926.451(a)(2)
Sec. 1926.452(t)(3)
Sec. 1926.451(r)(3)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(r)(4)..................... Sec. 1926.451(a)(1)
Sec. 1926.451(r)(5)..................... Sec. 1926.451(g)
Sec. 1926.451(e)(1)..................... Sec. 1926.451(c)(2)
Sec. 1926.451(e)(2)..................... Sec. 1926.451(a)(1)
Sec. 1926.452(w)(2)
Sec. 1926.451(e)(4)..................... Sec. 1926.451(b)(1)
[[Page 46080]]
Sec. 1926.451(e)(5)..................... Sec. 1926.451(e)(1)
Sec. 1926.451(e)(2)
Sec. 1926.451(e)(3)
Sec. 1926.451(e)(8)..................... Sec. 1926.451(c)(3)
Sec. 1926.451(d)(1)
Sec. 1926.452(w)(2)
Sec. 1926.451(e)(10).................... Sec. 1926.451(g)
----------------------------------------------------------------------------------------------------------------
Paragraph (a) Pole Scaffolds
Final rule paragraph (a) sets requirements for the proper use of
bearers, braces and runners on pole scaffolds. The corresponding
provision in existing Sec. 1926.451(b) is titled ``Wood pole
scaffolds.'' The final rule has deleted the word ``wood'' from the
title of the paragraph, since pole scaffolds can be constructed of
other materials. In addition, the final rule provides that pole
scaffolds over 60 feet in height be designed by a registered
professional engineer, and must be constructed and loaded in accordance
with that design. The provision also notes that non-mandatory Appendix
A contains examples of criteria that will enable an employer to comply
with design and loading requirements for pole scaffolds under 60 feet
in height. These provisions are virtually identical to those in the
proposal, except for minor editorial revisions for the sake of clarity,
as discussed below. In addition, as illustrated by Table 2, many
existing Sec. 1926.451(b) requirements are being carried forward in
paragraph (a) of Sec. 1926.452 of the final rule.
Table 2.--Provisions Being Renumbered in the Final Rule
------------------------------------------------------------------------
Existing paragraph Final rule paragraph
------------------------------------------------------------------------
Sec. 1926.451(b)(14)................. Sec. 1926.452(a)(1)
Sec. 1926.451(b)(9).................. Sec. 1926.452(a)(2)
Sec. 1926.451(b)(10)................. Sec. 1926.452(a)(3)
Sec. 1926.451(b)(10)................. Sec. 1926.452(a)(4)
Sec. 1926.451(b)(5).................. Sec. 1926.452(a)(5)
Sec. 1926.451(b)(5).................. Sec. 1926.452(a)(6)
Sec. 1926.451(b)(6).................. Sec. 1926.451(a)
Sec. 1926.451(b)(7).................. Sec. 1926.452(a)(7)
Sec. 1926.451(b)(7), (10)............ Sec. 1926.452(a)(8)
Sec. 1926.451(b)(2).................. Sec. 1926.452(a)(9)
Sec. 1926.451(b)(16)................. Sec. 1926.452(a)(10)
------------------------------------------------------------------------
OSHA received three comments (Exs. 2-13, 2-367 and 2-368) on
proposed Sec. 1926.452(a). The SSFI (Ex. 2-367) recommended that OSHA
change the term ``Ledger'' to ``Runners'' because ``Runners'' is the
correct terminology. OSHA agrees and has incorporated that change into
paragraph (a) of the final rule.
The other commenters (Exs. 2-13 and 2-368) objected to the proposed
deletion of the word ``wood'' from the title of this paragraph, stating
that this section refers only to wood pole scaffolds. OSHA believes
that all pole scaffolds, whatever their composition, need to be covered
by the criteria of proposed paragraph (a) and, accordingly, has not
made the suggested change.
Finally, the Agency has editorially revised the text of final rule
Sec. 1296.452(a)(10) to clarify that non-mandatory Appendix A contains
examples of criteria that will enable an employer to comply with design
and loading requirements for pole scaffolds under 60 feet in height,
and that pole scaffolds over 60 feet in height must be designed by a
registered professional engineer. This revision highlights the fact
that the proposed criteria and now the final rule criteria in non-
mandatory Appendix A are limited to heights of less than 60 feet.
Paragraph (b) Tube and Coupler Scaffolds
Paragraph (b) sets requirements for the use of bearers, bracing,
runners and couplers on tube and coupler scaffolds. In addition, the
final rule provides that tube and coupler scaffolds over 125 feet in
height be designed by a registered professional engineer, and be
constructed and loaded in accordance with such design. The provision
also notes that non-mandatory Appendix A contains examples of criteria
that will enable an employer to comply with design and loading
requirements for tube and coupler scaffolds under 125 feet in height.
These provisions are virtually identical to the proposed provisions,
except as discussed below.
Final rule paragraph (b)(1), which is identical to the
corresponding provision of the proposed rule, is a new requirement for
tube and coupler scaffolds. This provision requires that platforms not
be moved until the next location has been properly prepared to support
the platform being moved. This is the same requirement as existing
Sec. 1926.451(b)(14) (final rule Sec. 1926.452(a)(1)) for wood pole
(pole) scaffolds. This rule was added to this section because it
addressed the problem of platform stability during construction, a
problem which exists for tube and coupler scaffolds as well as pole
scaffolds.
Paragraph (b)(2) of the final rule requires the installation of
transverse bracing at the scaffold ends and, at least, at every third
set of posts horizontally and every fourth post vertically. This
paragraph provides for diagonal bracing from the outer or inner posts
or runners upward to the next outer or inner posts or runners. In
addition, building ties must be installed at the bearer levels between
the diagonal braces in conformance with Sec. 1926.451(c)(1). This
provision is consistent with existing Sec. 1926.451(c)(10).
This requirement differs from the proposed paragraph (b)(2), which
required transverse bracing to be installed for each section of six
levels between the fourth and sixth level.
The SSFI and the SIA (Exs. 2-367 and 2-368) recommended that
transverse bracing be installed at the base and be repeated every third
and fourth level vertically, and that building ties be installed ``at
bearer levels adjacent to the bracing'' (Ex. 2-367), or at ``the bearer
levels between the diagonal brace[s]'' (Ex. 2-368). In support of the
suggested change, the SIA (Ex. 2-368) stated ``[t]his revision would
correct the inaccuracy which has existed for years in the current
standard and will conform to proper engineering criteria.'' Another
commenter (Ex. 2-15) pointed out that the proposal did not require
transverse bracing at the base of the scaffold. In addition, a
commenter (Ex. 2-42) recommended that transverse bracing be installed
at the scaffold ends and at least at every third set of posts, that
such bracing be installed on every level and that it extend diagonally
from the inner or outer posts or runners.
OSHA has determined that the proposed bracing specifications would
not provide adequate structural stability for tube and coupler
scaffolds. In
[[Page 46081]]
particular, OSHA has concluded that bracing at the third and fourth
levels, as suggested by the SSFI and the SIA and as provided in ANSI
A10.8-1988, paragraph 8.11, will provide appropriate stability. On the
other hand, the Agency believes that bracing at every level would be
unnecessarily burdensome, perhaps even affecting the capacity of the
scaffold. Therefore, OSHA is returning to the approach taken by
existing Sec. 1926.451(c)(10). The Agency has concluded that compliance
with the suggested provisions will increase scaffold stability
appropriately and has revised the final rule to reflect this finding.
In addition, OSHA has drafted the final provision to indicate clearly
that the placement of building ties must comply with final rule
Sec. 1926.451(c)(1) (proposed as Sec. 1926.451(b)(13)).
Paragraph (b)(3) of the final rule, which is basically the same as
the proposed paragraph, is based on existing Sec. 1926.451(c)(11). This
provision sets requirements for the installation of longitudinal
bracing across the inner and outer rows of posts for straight run
scaffolds. In particular, such bracing must be installed diagonally in
both directions and shall extend from the base of the end posts upward
to the top of the scaffold at a 45 degree angle. Where scaffold length
is greater than height, bracing shall be repeated at least at every
fifth post. Where scaffold length is less than height, such bracing
shall be installed from the base of the end posts upward to the
opposite end posts and then in alternating directions until reaching
the top of the scaffold. In addition, bracing shall be installed as
close as possible to the intersection of the bearer and post or of the
runner and post. The proposed provision was identical, except that it
did not specify that only straight run scaffolds were covered or that
the bracing had to be installed as close as possible to a post's
intersection with bearers or runners.
The SSFI and the SIA (Exs. 2-367 and 2-368) suggested that OSHA
limit application of the proposed provision to straight run scaffolds
and that the Agency specify the proximity of bracing to the
intersection of posts with bearers or runners. The Agency believes that
limiting the provision to straight run scaffolds is appropriate, since
when a tube and coupler scaffold is installed around circular
structures or at corners, the inside leg is braced in the direction
perpendicular to the walkway (platform) because the runners come in at
less than 180 degrees. In addition, OSHA agrees that it is appropriate
to include requirements regarding where to position bracing, and the
final provision has been written accordingly. (Bracing requirements for
those tube and coupler scaffolds that are not straight run scaffolds
are found in final rule Sec. 1926.451(c).)
Paragraph (b)(4) of the final rule requires that bracing be
attached to the runners as close to the post as possible, where
conditions preclude attachment of bracing to posts. This provision is
basically the same as the proposed provision, which was based on
existing Sec. 1926.451(c)(11). OSHA has modified this provision based
on comments from the SSFI and the SIA (Exs. 2-367 and 2-368) which
suggested that ``as close to the post as possible'' be added to the end
of this paragraph. The Agency recognizes that attachment to the post,
while the most desirable option, is not always possible. In
circumstances where such attachment is not possible, OSHA has
determined that attachment to the runner, as close as possible to the
post, will still maximize directional stability and provide the
strength necessary to properly brace the scaffold.
Paragraphs (b)(5) through (b)(10) of the final rule are identical
to corresponding provisions of the proposed rule, except for some minor
editorial revision to paragraph (b)(10). As explained in the preamble
to the proposed rule (51 FR 42691), these provisions are based on
existing Secs. 1926.451 (b) and (c).
Paragraph (c) Fabricated Frame Scaffolds
Paragraph (c) of the final rule provides additional requirements
for fabricated frame scaffolds (tubular welded frame scaffolds). Two
commenters (Exs. 2-13 and 2-320) recommended that OSHA retain the
title, ``Tubular Welded Frame Scaffolds'' used in the existing rule. As
discussed above in reference to the definitions in Sec. 1926.450(b),
however, OSHA has not followed this suggestion but has retained the
existing title in parentheses after the new title. Paragraph (c) of the
final rule is virtually identical to the corresponding provision in the
proposal except as discussed below.
Paragraph (c)(1) of the final rule is a new requirement for
fabricated frame scaffolds. It requires that platforms not be moved
until the next location is properly prepared and ready to support the
platform being moved. This provision is necessary to ensure that the
scaffold is positioned on a level and stable surface, as discussed for
final rule Sec. 1926.451(b)(1), above.
Final rule paragraphs (c)(2), (c)(3) and (c)(6), which are
identical to the corresponding proposed paragraphs, are effectively
identical to existing Sec. 1926.451(d) (3), (5) and (9), respectively.
Final rule paragraph (c)(4), which is identical to the parallel
provision of the proposed rule, requires the locking together of end
frames, and is essentially the same as existing Sec. 1926.451(d)(6).
This requirement only applies where uplift forces are strong enough to
displace the end frames or panels, such as when a hoist is being used
that could snag the scaffold during a hoist operation.
Final rule paragraph (c)(5) specifies the proper placement of
platform support brackets. Improper placement of such cantilever
supports can significantly reduce their support capacity and thus
endanger employees working on top of the platform. Proposed paragraph
(c)(5) set seating requirements for brackets and required that brackets
not be bent or twisted from those positions. This provision of the
final rule is identical except that it also allows the use of bracket
systems to support loads other than employees only where the system has
been designed and built to withstand the tipping forces imposed by
those other loads.
OSHA received comments from the SSFI and the SIA (Exs. 2-367 and 2-
368) suggesting that such brackets be allowed for the support of
personnel but not for the storage or support of materials. Based on
those comments, Issue L-8 of the hearing notice solicited testimony and
supporting information regarding the revision of proposed
Sec. 1926.452(c)(5) to require that side brackets on fabricated frame
scaffolds ``* * * be used to support personnel only and shall not be
used for storage or support of materials.'' OSHA also indicated that,
in the Agency's opinion, this area would be adequately covered by
proposed Sec. 1926.451(a)(1), which sets capacity requirements, and
proposed Sec. 1926.451(d)(1), which prohibits overloading.
The SIA (Exs. 5a-16 and 10) stated that, since users may not know
the load capacities of their side brackets without consulting a loading
table, they may unintentionally overload the units. The SIA explained
that ``employees tend not to respect the dangers involved'' with side
bracket loads, which ``induce an eccentric load and overturning
propensity on the scaffold system.'' They further noted that the
``aisle'' provided by a series of side brackets is typically 20 inches
wide, which provides insufficient room for employees to step around
stored material. The SIA testimony (Tr. 3/22/88, p. 160) repeated these
concerns but added that bracket systems properly
[[Page 46082]]
designed to take loads other than workers should not be prohibited by
the final rule.
Bristol Steel (Exs. 5a-3 and 13) stated that proposed
Sec. 1926.451(a)(1) and (d)(1) would adequately address the SIA and
SSFI concerns, and therefore did not support the suggested additional
language.
After carefully considering the above-described comments, OSHA has
determined that fabricated frame scaffolds which utilize bracket
systems must be used only to support personnel, unless the scaffold has
been designed for other loads by a qualified engineer and been built to
withstand the tipping forces caused by the loads being placed on the
bracket supported section of the scaffold. The final rule reflects this
determination (paragraph (c)(5)(iii)). OSHA believes that compliance
with this requirement will provide employees working on fabricated
frame scaffolds with the protection they need while working on this
type of scaffold.
Paragraph (d) Plasterers', Decorators' and Large Area Scaffolds
(d) of the final rule requires that plasterers', decorators' and
large area scaffolds be constructed in accordance with
Sec. 1926.452(a), (b), or (c) of this section. This requirement is
identical to that in the proposed rule. Paragraph (d) references the
provisions of paragraphs (a), (b), and (c) because plasters',
decorators' and large area scaffolds are almost always constructed
using pole scaffolds, tube and coupler scaffolds, or fabricated frame
scaffolds. The existing rule, Sec. 1926.451(q)(1), required that the
scaffolds in question be built only according to the existing rules for
pole scaffolds. OSHA believes that compliance with the provisions of
Secs. 1926.452(a), (b) or (c) will provide appropriate protection for
employees covered by paragraph (d).
Paragraph (e) Bricklayers' Square Scaffolds (Squares)
Paragraph (e) provides additional requirements for bricklayers'
square scaffolds (squares). This paragraph requires that scaffolds made
of wood be reinforced with gussets on both sides of each corner
(paragraph (e)(1)); that diagonal braces be installed on all sides of
each square (paragraph (e)(2)); that diagonal braces be installed
between squares on the rear and front sides of the scaffold, and extend
from the bottom of each square to the top of the next square (paragraph
(e)(3)); and that scaffolds of this type not exceed three tiers in
height, that they be constructed and arranged so that one square rests
directly above the other, and that the upper tiers stand on a
continuous row of planks laid across the next lower tier and be nailed
down or otherwise secured to prevent displacement (paragraph (e)(4)).
These requirements are identical to those in the proposed rule.
Final rule paragraphs (e)(1), (2), and (3) contain essentially the
same requirements as existing Secs. 1926.451(n)(3) and (4), except that
the specific requirements for the size of the member are being replaced
by the capacity requirements of Sec. 1926.451(a)(1). OSHA notes that
non-mandatory Appendix A of this final rule provides examples of
component dimensions for bricklayers' square scaffolds that would be
deemed to comply with Sec. 1926.451(a)(1). Final rule paragraph (e)(4)
contains the same requirement as existing Sec. 1926.451(n)(6).
Paragraph (f) Horse Scaffolds
Paragraph (f) provides additional requirements for horse scaffolds.
This paragraph requires that horse scaffolds not be constructed or
arranged more than two tiers or 10 feet (3.0 m) in height, whichever is
less (paragraph (f)(1)); when arranged in tiers, that each horse be
placed directly over the horse in the tier below (paragraph (f)(2));
when arranged in tiers, the legs of each horse shall be nailed down or
otherwise secured to prevent displacement (paragraph (f)(3)); and that,
when arranged in tiers, each tier shall be crossbraced (paragraph
(f)(4)). These requirements, which are identical to the parallel
provisions of the proposed rule, correspond to existing
Sec. 1926.451(o)(1), (o)(4) and (o)(5), respectively.
Paragraph (g) Form Scaffolds and Carpenters' Bracket Scaffolds
Paragraph (g) of the final rule, which is effectively unchanged
since the proposal, provides additional rules for form scaffolds and
carpenters' bracket scaffolds. Under the existing standard, carpenters'
bracket scaffolds and form scaffolds are addressed separately (existing
Secs. 1926.451(m) and (x), respectively). However, OSHA has determined
that the two types are so similar that it is appropriate to address
them in a single paragraph.
Final rule paragraph (g)(1) carries forward the requirements for
attachment of a scaffold to a supporting framework or structure set by
existing Sec. 1926.451(m)(2), (x)(4)(ii), and (x)(5).
Paragraph (g)(2), in turn, maintains the existing
Sec. 1926.451(x)(6)(i) requirement that wooden bracket form scaffolds
be an integral part of the form panel. Paragraph (g)(3), like existing
Sec. 1926.451(x)(5)(i), requires that folding type metal brackets, when
extended for use, shall be either bolted or secured with a locking-type
pin.
Paragraph (h) Roof Bracket Scaffolds
Paragraph (h) of the final rule provides additional requirements
for roof bracket scaffolds. This paragraph requires that scaffold
brackets be constructed to fit the pitch of the roof and provide a
level support for the platform (paragraph (h)(1)); and that brackets be
anchored in place by nails unless it is impractical to use nails
(paragraph (h)(2)). Paragraph (h)(2) further provides that brackets
shall be held in place with first-grade manila rope of at least three-
fourth inch diameter, or a rope with equivalent strength, when nails
are not used. These provisions are essentially identical to the
corresponding proposed provisions and to existing Secs. 1926.451(u)(1)
and (u)(2), respectively.
Existing Sec. 1926.451(u)(3) requires the installation of catch
platforms below the working area of roofs more than 16 feet from the
ground and having a slope greater than 4 inches in 12 inches without a
parapet. This provision also requires that the platform extend at least
2 feet from the eaves and that employees be protected from falls by a
guardrail system unless employees are using personal fall arrest
systems. The existing provision is being replaced by the general fall
protection requirements of Sec. 1926.451(g). The final rule, like the
proposal, allows guardrails on roof bracket scaffolds to be mounted on
a catch platform or be attached to the eaves. Therefore, the Agency has
concluded that there is no need to mention catch platforms in this
provision. OSHA has determined that it is appropriate to allow
employers flexibility in choosing where to attach guardrails. The
Agency notes that a catch platform is an elevated work platform that
meets the definition of a scaffold and therefore must comply with the
pertinent provisions of this final rule.
Paragraph (i) Outrigger Scaffolds
Paragraph Sec. 1926.452(i) of the final rule provides additional
requirements for outrigger scaffolds. Except for editorial changes, as
noted below, the requirements of the final rule are identical to those
of the proposed rule. Paragraphs (i)(1) through (i)(4), which set
requirements for the proper positioning and securing of outrigger
beams, are consistent with existing Sec. 1926.451(g)(1). Some editorial
changes have been made to proposed paragraph (i)(2), as suggested by a
commenter (Ex. 2-64), in order to clarify OSHA's
[[Page 46083]]
regulatory intent that the supporting beam be used in its strongest
orientation. Paragraphs (i)(5) and (i)(6), which require that the
inboard ends of outrigger beams be securely anchored and that the
entire supporting structure be securely braced, respectively, are
effectively identical to existing Sec. 1926.451(g)(2). Proposed
paragraph (i)(5) has undergone minor editorial changes since the
proposal: the existing provisions have been broken down into their
component parts to facilitate compliance.
Final rule paragraph (i)(7), which is identical to the
corresponding requirement in the proposed rule, requires that platform
units be nailed, bolted or otherwise secured to outriggers, to prevent
displacement. The corresponding language in existing
Sec. 1926.451(g)(4) required simply that planking be secured to the
beams. OSHA believes that the revised language better expresses the
Agency's intention that employers use effective means when securing
platform units to outrigger beams.
Paragraph (i)(8) requires that scaffolds and scaffold components be
designed by a registered professional engineer and constructed and
loaded in accordance with such design. This provision has been revised
to reflect OSHA's determination that the design of this type of
scaffold involves calculations that required the skills of a registered
professional engineer, and that the criteria in the proposed rule had
such limited applicability as to be of virtually no help to employers
in almost all situations. The proposed rule was based on existing
Sec. 1926.451(g)(3).
Paragraph (j) Pump Jack Scaffolds
Paragraph 1926.452(j) of the final rule provides additional rules
for pump jack scaffolds. Paragraph (j)(1) requires that pump jack
brackets, braces, and accessories be fabricated from metal plates and
angles. In addition, each pump jack bracket shall have two positive
gripping mechanisms to prevent any failure or slippage. This provision
is identical to the proposed paragraph and to existing
Sec. 1926.451(y)(2).
Paragraph (j)(2) requires that poles be secured to the structure by
rigid triangular bracing or equivalent, at the bottom, top, and other
points as necessary. In addition, that provision further requires that
when the pump jack has to pass bracing that is already installed, an
additional brace must be installed approximately four feet (1.2 m)
above the brace to be passed. That additional brace must be left in
place until the pump jack has been moved and the original brace
reinstalled. These requirements, which are identical to the proposed
paragraph except for an editorial revision, are essentially the same as
existing Secs. 1926.451(y)(4) (iii) and (iv).
NPRM Issues 9 and 22 asked for comments about whether OSHA should
remove the requirement for bottom braces on pump jack scaffolds. One
commenter (Ex. 2-13) stated that from his experience, * * * ``no one
uses any but the top pole brace.'' Another commenter (Ex. 2-31) agreed
with this assessment, saying, in part, ``[i]n terms of common practice,
the bottom brace is virtually nonexistent. In terms of practicality,
homeowners do not permit holes made in their foundation.'' This same
commenter continued that ``[i]n terms of functions, the bottom brace
does not relieve the pole from breaking,'' and added as follows:
There exists the misconception that a pumpjack pole will shoot
out when a load is applied to it. Fact is, the greater the load, the
greater the anchorage. Our in plant testing is done with no brace
securement. This, along with my 10 years plus of field inspections,
substantiates the unreality of a bottom brace. More accidents would
be experienced from tripping over bottom braces; and eye accidents
from securement to concrete. Overwhelmingly, the bottom brace simply
does not belong. When a wooden pumpjack pole is used,
Sec. 1926.451(a)(1) can better be achieved with mid-bracing. The
location of a pumpjack on a pole is not a true fulcrum point. That
is an erroneous assumption that precedes the pole pulling away from
the wall at the bottom assumption.
NIOSH recommended (Ex. 2-40) bracing or securing the bottom of pump
scaffold columns ``in some manner at all times.'' NIOSH stated that if
``the employer chooses to brace in a different manner than suggested by
the [existing] regulations, then the method used must be shown to be
equivalent to that required by the regulations.''
Another commenter (Ex. 2-54) stated the ``bottom brace should
remain for poles, [because that part of the scaffold] is the one part
that is easiest to hit and move.'' The commenter added that the
``bottom brace seems like the one that is needed the most * * *'' After
reviewing this issue, the ACCSH also recommended that the requirement
for a bottom brace be retained (Tr. 6/9/87, pp. 95-96).
Based on its review of the comments, OSHA has determined that
employers do need to brace the bottom of the support pole to keep it in
place, but that it is not necessary to specify the use of a rigid
triangular bottom brace. Other methods, such as anchoring the pole to
the ground, would provide equivalent support. Therefore, the final rule
requires, as did the proposal, that pumpjack poles be braced at the
bottom by triangular bracing or equivalent means.
A commenter (Ex. 2-52) stated that ``[a] requirement for braces
every ten vertical feet has been eliminated. Insofar as the same
applies to wooden poles, we believe this requirement should be
maintained in the Regulations.'' OSHA is aware that existing
Sec. 1926.451(y)(4)(i) provides for 10 foot spacing of poles (center to
center) when wood scaffold planks are used as platforms for pump jack
scaffolds. That paragraph further provides that pole spacing may exceed
10 feet center to center when fabricated platforms are used that fully
comply with all other provisions of existing paragraph (y). The Agency
proposed to delete existing paragraph (y)(4)(i) because OSHA believed
that compliance with the capacity requirements of proposed
Sec. 1926.451 (a)(1) would provide adequate assurance that a pump jack
scaffold was structurally sound and able to hold the anticipated loads.
As indicated above, the Agency believes that it is appropriate to focus
on the capacity of the scaffold, not on the exact spacing of the
braces, when evaluating the adequacy of a particular pump jack
scaffold. Accordingly, OSHA has not made the suggested change.
That commenter also stated ``The explanation for additional bracing
is confusing. We believe the phrase `on the side opposite the brace
from the pump jack' should read: `above the brace to be passed'.'' OSHA
agrees that the suggested language, which appears in existing
Sec. 1926.451(y)(4)(iv), more clearly expresses the Agency's intent,
and this is reflected in the final rule at paragraph (j)(2).
Paragraph (j)(3) provides, when guardrails are used for fall
protection, that a workbench may be used as the toprail only if the
workbench complies with the requirements of Secs. 1926.451(g)(4) (ii),
(vii), (viii) and (xiii). This provision is effectively identical both
to the proposed provision and to existing Sec. 1926.451(y)(12).
Paragraph (j)(4) provides that work benches shall not be used as
scaffold platforms. This provision, which is identical to the
corresponding provision of the proposed rule, is effectively identical
to existing Sec. 1926.451(y)(13).
Paragraph (j)(5) provides, when poles are made of wood, that the
pole lumber shall be straight-grained, free of shakes, large loose or
dead knots, and other defects which might impair strength. This
provision, which is unchanged from that in the proposed rule, is based
on existing Sec. 1926.451(y)(6). OSHA has deleted existing
specification language
[[Page 46084]]
which addressed the dimensions and type of wood to be used, because
OSHA believes that wood poles which comply with the performance
requirements of final rule Sec. 1926.451(a)(1) will provide adequate
protection for affected employees.
Paragraph (j)(6) provides, when wood poles are constructed of two
continuous lengths, that the lengths shall be joined together with the
seam parallel to the bracket. This provision, which is unchanged from
the corresponding provision of the proposed rule, is based on existing
Sec. 1926.451(y)(7). The Agency has deleted the existing specification
language, which addressed the dimensions of the wood to be used and the
means of joining, because OSHA believes, again, that compliance with
Sec. 1926.451(a)(1) will provide adequate protection for affected
employees. The Agency notes that the language in question has been
included in non-mandatory Appendix A to provide an example of how an
employer could comply with Sec. 1926.451(a).
Final rule paragraph (j)(7) requires, when two by fours are spliced
to make a pole, that mending plates be installed at all splices to
develop the full strength of the member. This provision differs from
the proposed requirement because it requires mending plates at splices.
Proposed paragraph (j)(7) required that splices be constructed to
develop the full strength of the member, but did not require mending
plates.
NPRM Issue 9 asked whether proposed paragraph (j)(7) should require
mending plates on all spliced wooden poles. One commenter (Ex. 2-13)
wanted the Agency to prohibit the splicing of wood poles used for pump
jack scaffolds. His explanation was that:
[t]here is no splice that can equal the strength of the total
pole cross section. Wood pole lengths should be limited to
commercially available lengths.
From my experience, at work sites across this nation, no one
uses any but the top pole brace. All the more reason to eliminate
splicing to gain added pole lengths.
The same commenter added ``[t]he vast majority of the accidents
involving pump jack scaffolds are caused by pole failure at a splice''.
Another commenter (Ex. 2-31) said that a mending plate addresses
the typical way a wooden pole breaks, i.e., laterally. He added that
in-house tests conducted by his firm showed that poles with the plates
are three times stronger than those without them, and went on to say
that the cost factor for plate use is negligible. The ACCSH also
recommended that mending plates be used on all splices (Tr. 6/9/87, pp.
95-96).
Based on its review of the comments and its knowledge of pumpjack
scaffolds, OSHA has determined that mending plates provide an
appropriate increase in the strength of spliced poles, and final rule
paragraph (j)(7) reflects this determination. OSHA also believes that
requiring wood poles to be made entirely of one piece of wood (i.e., no
splices) would not be realistic because many contractors use this type
of scaffold and splices with mending plates are at least as strong as
unspliced wood. Although OSHA is aware that splices are potential weak
points in a pole, the Agency finds that mending plates provide
assurance that the spliced pole has adequate strength.
Several commenters (Exs. 2-23, 2-31 and 2-52) suggested that the
final rule include the general requirements applicable to pump jack
scaffolds found in this section of OSHA's existing scaffold standard.
However, the final rule sets out general requirements for all
scaffolds, including pump jack scaffolds, in Sec. 1926.451, and OSHA
has therefore not made the suggested change.
Paragraph (k) Ladder Jack Scaffolds
Paragraph 1926.452(k) of the final rule provides additional
requirements for ladder jack scaffolds. Paragraph (k)(1) provides that
platforms shall not exceed a height of 20 feet (6.1 m). This provision,
which is identical to that in the proposed rule, is based on existing
Sec. 1926.451(s)(1) and current safe industry practice.
Paragraph (k)(2) requires that all ladders used to support ladder
jack scaffolds meet the requirements of subpart X of 29 CFR part 1926--
Stairways and Ladders, except that job-made ladders, which are
permitted by subpart X, are not permitted to be used to support ladder
jack scaffolds. This provision, which is identical to the parallel
requirement in the proposed rule, is consistent with existing
Sec. 1926.451(s)(2). The existing standard referenced two national
consensus standards which, as subsequently updated, have been
incorporated into the pertinent provisions of subpart X. In particular,
existing Sec. 1926.451(s)(2) implicitly prohibited the use of job-built
ladders.
Two commenters (Exs. 2-20 and 2-55) opposed the proposed
prohibition on the use of job-made ladders as ladder jack scaffold
support, and stated that job-made ladders constructed according to
proposed Sec. 1926.1053 (subpart X) could serve as adequate supports
for ladder jack scaffolds. However, OSHA concludes, based on the record
and the Agency's experience in the construction industry, that job-made
ladders that comply with the requirements of Sec. 1926.1053 may not be
able to support the heavy point loading imposed by ladder jack scaffold
brackets. OSHA has therefore determined that the use of a job-made
ladder to support a ladder jack scaffold could lead to scaffold
collapse, and the final rule reflects this finding. OSHA's final rule
is thus consistent on this point with the position taken by the
corresponding ANSI standard, A10.8-1988, paragraph 17.2.2, which
provides that only manufactured ladders may be used to support ladder-
type scaffolds or platforms.
Paragraph (k)(3) provides that the ladder jack be so designed and
constructed that it will bear either on the side rails and ladder rungs
or on the ladder rungs alone. This paragraph further requires that the
bearing area for a ladder jack that bears only on the rungs shall be at
least 10 inches (25.4 cm) on each rung to ensure adequate support. This
provision, which is identical to that in the proposed rule, is
effectively identical to existing Sec. 1926.451(s)(3).
Paragraph (k)(4) requires that ladders used to support ladder jacks
be placed, fastened, or equipped with devices to prevent slipping. This
provision, which is identical to that in the proposed rule, is
effectively identical to existing Sec. 1926.451(s)(4) and is intended
to prevent employee falls caused by displacement of the ladder.
Paragraph (k)(5) provides that scaffold platforms shall not be
bridged one to another. This paragraph, which is identical to the
proposed requirement, is a new requirement that is intended to ensure
the stability of the system and to prevent accidental overloading. The
provision would prohibit situations where, for example, four ladders
are used to support three platforms. OSHA is prohibiting bridging
because this practice often leads to overloading of the two ladders in
the middle. This provision does not prohibit passage from one scaffold
to another if the scaffolds are close enough for employees to walk (but
not to jump or swing) from one scaffold to the other.
Three commenters [Exs. 2-23, 2-367, and 2-368] urged OSHA to
include specific language in the final rule addressing acceptable
dimensions and loading of ladder jack scaffolds. OSHA has not made the
suggested revisions because the Agency believes that the capacity
requirements found in final rule Sec. 1926.451(a) adequately address
these matters.
Another commenter (Ex. 2-308) recommended that ladder jack
scaffolds be prohibited because they ``cannot be
[[Page 46085]]
secured at the top,'' safe access is not possible, and an anchorage for
attaching a lifeline or lanyard is not available. Although the Agency
agrees that the conditions described by this commenter may occur in
some construction situations, they are not characteristic of ladder
jack scaffolds per se. Employers using ladder jack scaffolds must still
comply with the applicable general requirements of Sec. 1926.451, such
as those addressing capacity, access and fall protection, i.e., the
three situations mentioned by the commenter. In particular, employees
working on ladder jack scaffolds must be protected from fall hazards by
personal fall arrest systems which comply with the criteria set in
subpart M, Sec. 1926.502(d) (Fall protection) (final rule
Sec. 1926.451(g)(1)(ii)). Ladder jack scaffolds which do not comply
with those requirements must not be used.
Based on the rulemaking record and the Agency's own experience,
OSHA has determined that ladder jack scaffolds used in compliance with
the requirements of the final rule provide acceptable and safe working
surfaces for employees. Accordingly, the final rule does not prohibit
the use of ladder jack scaffolds.
Paragraph (l) Window Jack Scaffolds
Paragraph (l) of the final rule provides additional requirements
for window jack scaffolds. This paragraph provides that window jack
scaffolds shall be securely attached to the window opening (paragraph
(l)(1)), shall be used only for the purpose of working at the window
opening through which the jack is placed (paragraph (l)(2)) and shall
not be used to support planks placed between one window jack and
another, or to support other elements of scaffolding. These
requirements are necessary to ensure the safety of employees working
from these platforms.
These provisions of the final rule are identical to the
corresponding proposed provisions. Paragraph (l)(1) is a new
requirement, and is intended to ensure that the scaffold is not
accidentally displaced. Final rule paragraphs (l)(2) and (l)(3) are
identical to existing Secs. 1926.451(t)(1) and (t)(2), respectively.
Paragraph (m) Crawling Boards
Paragraph (m) of the final rule provides additional requirements
for crawling boards (chicken ladders). The final rule requires that
crawling boards extend from the roof peak to the eaves when used in
connection with roof construction, repair, or maintenance (paragraph
(m)(1)), and that crawling boards be secured to the roof by ridge hooks
or by means which satisfy equivalent criteria (e.g., strength and
durability) (paragraph (m)(2)). These requirements are designed to
ensure that crawling boards used by employees performing roof work are
as secure as possible.
The provisions of the final rule, which are effectively identical
to those of the proposed paragraph, are based on requirements in
existing Secs. 1926.451(v) (1) and (3), respectively. The other
provisions of existing Sec. 1926.451(v)(1) are being relocated to non-
mandatory Appendix A since they have been replaced by the capacity
requirements of revised Sec. 1926.451(a)(1). The existing rule's
requirement to clinch nails has been deleted because the
inaccessibility of many nail points makes clinching impossible.
Existing Sec. 1926.451(v)(2) is being replaced by the fall protection
requirements of revised Sec. 1926.451(e)(1).
Paragraph (n) Step, Platform, and Trestle Ladder Scaffolds
Paragraph (n) of the final rule provides additional requirements
for step, platform, and trestle ladder scaffolds. The provisions of
final rule paragraph (n) are virtually identical to the provisions of
the proposed paragraph.
Paragraph (n)(1) provides that scaffold platforms not be placed any
higher than the second highest rung or step of the ladder supporting
the platform. This provision is consistent with paragraphs 17.4 and
17.5 of ANSI A10.8-1988, and is intended to ensure the stability of
this type of scaffold.
Paragraph (n)(2) requires that all ladders used in conjunction with
step, platform and trestle ladder scaffolds meet the requirements of
subpart X of 29 CFR part 1926--Stairways and Ladders, except that job-
made ladders must not be used to support such scaffolds. A commenter
(Ex. 2-23) suggested that ladders used in conjunction with step,
platform and trestle ladder scaffolds be required to comply with
subpart X or with the pertinent ANSI standards. The commenter also
suggested that OSHA prohibit the use of job-made ladders to support
such scaffolds. Final rule paragraph (n)(2), which is identical to the
proposed paragraph, addresses both of these concerns.
Paragraph (n)(3) provides that ladders used to support step,
platform, and trestle ladder scaffolds shall be placed, fastened, or
equipped with devices to prevent slipping. Paragraph (n)(4) requires
that scaffolds not be bridged one to another. Bridging, as discussed
above under paragraph (k)(5), occurs when four ladders are used to
support three platforms. OSHA is prohibiting bridging because this
practice often leads to overloading of the two ladders in the middle.
Although step, platform and trestle ladder scaffolds were not
specifically addressed in OSHA's existing scaffold rule, they are
covered by the general requirements in existing rule Sec. 1926.451(a).
Final rule paragraphs (n) (2), (3), and (4) correspond to the
ladder jack scaffold provisions in final rule Sec. 1926.451(k) (2), (4)
and (5), respectively. The ``ladder-type'' scaffolds covered by
paragraph (n) differ from ladder jack scaffolds in that the platform
rests directly on the ladder step or rung, whereas ladder jack scaffold
platforms rest on brackets.
Paragraph (o) Single-point Adjustable Scaffolds
Paragraph (o) provides additional requirements for single-point
adjustable scaffolds. This paragraph combines existing
Sec. 1926.451(k), single-point adjustable suspension scaffolds, and
Sec. 1926.451(l), boatswains' chairs, because boatswains' chairs are a
form of single-point adjustable suspension scaffold. One commenter (Ex.
2-23) opposed the combining of these paragraphs from the existing rule
because they [boatswains' chairs and other single-point adjustable
scaffolds] ``have different requirements because of the different
positions in which the rider rides.'' OSHA has determined, however,
that the characteristics of single-point adjustable suspension
scaffolds and boatswains' chairs are sufficiently similar so that the
requirements of final rule paragraph (o), along with the general
requirements in Sec. 1926.451, appropriately address both types of
scaffolds.
Paragraph (o)(1) provides, when two single-point adjustable
suspension scaffolds are combined to form a two-point adjustable
suspension scaffold, that the resulting scaffold meet the requirements
for two-point adjustable suspension scaffolds in final rule paragraph
(p). This provision, which is identical to the proposed paragraph, is
based on existing Sec. 1926.451(k)(6).
Paragraph (o)(2) addresses the circumstances under which the
supporting rope between a scaffold and a suspension device is permitted
to deviate from a vertical position (i.e., at a 90 degree angle from
level grade). This paragraph requires that the supporting rope between
the scaffold and the suspension device be kept vertical unless the
following four conditions are met: the rigging must have been designed
by a qualified person; the scaffold must be accessible to rescuers;
[[Page 46086]]
the supporting rope must be protected to ensure that it will not chafe
at any point where a change in direction occurs; and the scaffold must
not be able to sway into another surface. Whenever swaying of the
scaffold could bring the scaffold into contact with another surface,
the supporting rope must be vertical, with no exceptions.
Proposed paragraph 1926.452(o)(2) required that supporting ropes be
vertical and be kept from swaying, except where the scaffold is on the
outside of a dome-like or slanted structure and the appropriate
supports have been designed and installed. NPRM Issue 10 noted that
existing Sec. 1926.451(k)(7) requires the support rope for single-point
adjustable suspension scaffolds to be vertical. OSHA asked if the
exception provided by proposed paragraph (o)(2) was appropriate. The
Agency further requested suggestions regarding a maximum permissible
angle and any other conditions that needed to be specified.
The AGC (Exs. 2-20, 2-55, and 2-390) stated that ``[a]ngles that
are too severe would impair work operation and thus preclude the use of
suspensions.'' Another commenter (Ex. 2-69) echoed that view, and added
that ``[f]lexibility is needed for certain operations when using
suspended scaffolds.'' A manufacturer (Ex. 2-43) mentioned skylight and
barrel-vault work as examples of situations which preclude the use of
vertical lines. The commenter also stated ``* * * when suspended, the
worker must be accessible to rescuers. One can envision a worker
dangling in space below a dome with no way to get to him.''
Another commenter (Ex. 2-64) stated ``[t]he supporting rope for
single-point adjustable suspension scaffolds should be allowed to
deviate from vertical without defining any maximum limits. Each
situation under these conditions is a special case and has its own
limiting circumstances. It would not be feasible to establish standard
limits for all possible special situations.'' (emphasis in original)
Another commenter (Ex. 2-22) stated that deviation from vertical
should be permitted. The commenter further stated ``[t]he same
practical field problems arise in the case of a curved surface of any
type as does in the case of the dome-type or slanted structure. There
is no safety difference in the three special situations and they
require an exception because of their unique character.''
One commenter (Ex. 2-13) stated as follows:
There never was a reason for the suspension rope for a single
point suspension scaffold to be vertical. In fact, most are used
with the rope other than vertical. The same applies for two point
suspension scaffolds. There is no maximum or minimum angle of
deviation from the vertical. The load reaction to the rope does not
change; but the rope(s) must be protected from sharp edges at the
change in direction.
In addition, the SSFI and the SIA (Exs. 2-367 and 2-368) addressed
this issue in their comments on proposed 1926.452(o)(2). They
recommended that, when a scaffold is on the outside of a dome-type,
slanted or set-in structure, the use of intermediate supports to change
the direction of the rope from the vertical be allowed provided that
such supports have been designed by a competent person and have been
installed in a manner that prevents chafing of the rope.
The SIA (Ex. 2-368) commented that ``[m]any work operations require
non-vertical lines due to set-backs, curved surfaces, areas under
soffits, following a bowser line, spherical water tanks, etc.'' In
addition, the SSFI responded to Issue 10 as follows ``[t]he SSFI agrees
that some deviation from vertical support should be allowed. Cases in
which this would occur are special in nature and should only be allowed
when designed by a competent person.''
The ACCSH (Tr. 96-97, 6-9-87) recommended that deviation from
vertical should be allowed only under the supervision of a ``qualified
person.'' A member of the ACCSH stated that the qualified person would
be ``a competent design engineer that has experience in this
discipline.''
OSHA agrees that there are circumstances where the support lines of
single-point adjustable suspension scaffolds need to deviate from
vertical, and that under controlled circumstances, the swaying of
support lines should be allowed. The Agency concludes that the
requirements for design by a qualified person, accessibility to
rescuers, protection of supporting rope from chafing, and prohibition
of swaying where the scaffold could contact another surface are
appropriate measures, and final rule paragraph (o)(2) reflects this
determination.
Paragraph (o)(3) requires that the tackle used with boatswains'
chairs be ball bearing or bushed blocks containing safety hooks and
properly ``eye'' spliced minimum five-eight (\5/8\) inch (1.6 cm)
diameter first grade manila rope, or other rope that meets the
performance criteria of the above-specified manila rope. The proposed
provision, based on existing Sec. 1926.451(l)(5), was effectively
identical, except that it did not specifically address the hook used to
suspend the boatswains' chair. OSHA recognizes that the use of an open
hook could allow a chair to be dislodged if the rigging hung up on an
obstruction. The corresponding ANSI standard, A10.8-1988, paragraph
6.14.5, provides for the use of a hook with a safety latch over the
opening (safety hook) to prevent dislodging of the chair. The Agency
agrees that it is appropriate to explicitly require that employers who
have their employees use boatswains' chair rig their scaffolds with
safety hooks and has revised the proposed rule accordingly. In
addition, OSHA believes that locking safety hooks, such as are required
for use with crane and derrick suspended personnel platforms
(Sec. 1926.550(g)(4)(iv)(B)), would provide the most effective
protection for affected employees. A minor editorial revision to the
proposed paragraph replaces the phrase ``or equivalent'' with language
which states clearly that any rope used in lieu of \5/8\ inch diameter
first grade manila rope must, at least, satisfy the final rule's
criteria (e.g., strength and durability) for manila rope.
Paragraph (o)(4) provides that boatswains' chair seat slings be
reeved through four corner holes in the seat; shall cross each other on
the underside of the seat; and shall be rigged so as to prevent
slippage which could cause an out-of-level condition. This paragraph,
which is identical to the proposed provision and is based on existing
Sec. 1926.451(l)(2), is intended to prevent tipping of the chair.
Paragraph (o)(5) requires, except as provided in paragraph (o)(6),
that boatswains' chair seat slings be a minimum of five-eight (\5/8\)
inch (1.6 cm) diameter fiber or synthetic rope or other rope which
satisfies equivalent performance criteria. This provision, which is
substantively identical to the proposed provision, is based on existing
Sec. 1926.451(l)(2). A minor editorial revision to the proposed
paragraph replaces the phrase ``or equivalent'' with language which
states clearly that any rope used in lieu of \5/8\ inch diameter fiber
or synthetic rope must, at least, satisfy the final rule's criteria
(e.g., strength, slip resistance, and durability) for fiber or
synthetic rope. In addition, the final rule has deleted the proposed
language ``when employees are not using a heat-producing process such
as gas or arc welding'' as being unnecessary since final rule paragraph
(o)(6) specifically addresses the issue of rope use when heat producing
processes are in operation.
Paragraph (o)(6) requires that boatswains' chair seat slings be a
[[Page 46087]]
minimum of three-eight (\3/8\) inch (1.0 cm) wire rope, when a heat-
producing process such as gas or arc welding is being conducted. This
provision, which is substantively identical to the proposed provision
and is based on existing Sec. 1926.451(l)(3), is necessary to ensure
that the chair's sling is made of fire-resistant materials.
Paragraph (o)(7) requires that non-cross-laminated wood
boatswains's chairs be reinforced on their underside by cleats securely
fastened to prevent the board from splitting. This provision is
identical to the proposed provision. Existing Sec. 1926.451(l)(1)
requires all boatswains' chairs to be cleated. As noted in the preamble
to the proposed rule (51 FR 42694), this paragraph recognizes that
plywood-type wood seats which comply with Sec. 1926.451(a)(1) are
strong enough to use as boatswains' chairs without being reinforced
with cleats.
Paragraph (p) Two-point Adjustable Suspension Scaffolds (Swing Stages)
Paragraph (p) provides additional requirements for two-point
adjustable suspension scaffolds (swing stages). The introduction to
this paragraph states that paragraph (q) addresses stonesetters' multi-
point adjustable suspension scaffolds, masons' multi-point adjustable
suspension scaffolds or other multi-point suspension scaffolds.
Paragraph (p)(1) provides that platforms not be more than 36 inches
(0.9 m) wide unless designed by a qualified person to prevent unstable
conditions. This provision, which is identical to proposed paragraph
(p)(1), is essentially the same as existing Sec. 1926.451(i)(1), which
limits platform width to 36 inches.
A commenter (Ex. 2-23) recommended that such platforms ``* * * not
be less than 20 inches nor more than 36 (0.9 m) inches wide unless
designed by a registered civil or mechanical engineer to prevent
unstable conditions.'' OSHA has not adopted the commenter's
recommendation for a 20-inch minimum width, because the Agency
considers the 18-inch minimum platform width set in final rule
Sec. 1926.451(b)(2) to be adequate. In addition, OSHA has not adopted a
requirement for a platform wider than 36 inches to be designed by a
registered engineer, because the Agency believes that a person who is
``qualified'' as defined in both Sec. 1926.450(b) and Sec. 1926.32(m)
will have the skills and expertise needed to design such a platform.
Paragraph (p)(2) requires that the platform be securely fastened to
hangers (stirrups) by U-bolts or other means which satisfy
Sec. 1926.451(a). This provision is based on existing
Sec. 1926.451(i)(1). Proposed paragraph (p)(2) has been editorially
revised to replace the term ``equivalent means'' with language which
indicates clearly that ``other'' means of fastening the platform to
hangers must satisfy the criteria of Sec. 1926.451(a).
Paragraph (p)(3) provides that the blocks for fiber or synthetic
ropes consist of at least one double and one single block, and that the
sheaves of all blocks fit the size of the rope used. This provision,
which is identical to the proposed provision and is based on existing
Sec. 1926.451(i)(6), is intended to ensure that these types of rope are
maintained under proper tension and do not slip out of their sheaves.
Paragraph (p)(4) requires that platforms be of the ladder-type,
plank-type, beam-type, or light-metal type. Light metal-type platforms
having a rated capacity of 750 pounds or less and platforms 40 feet
(12.2 m) or less in length shall be tested and listed by a nationally-
recognized testing laboratory. This provision is based on existing
Sec. 1926.451(i)(10). Proposed paragraph (p)(4) was similar to this
provision of the final rule, except that the final rule excludes
platforms rated over 750 pounds or platforms longer than 40 feet. This
revision has been made based on a comment (Ex. 2-539) which stated:
Underwriters' Laboratories has issued a standard for safety
called UL 1322 covering fabricated scaffold stages. This standard
covers stage platforms with loads up to 750 pounds and lengths up to
40 feet. They do not have standards covering heavier loads or longer
lengths. It is not practical to have a requirement for UL testing
and approval on products that UL arbitrarily refuses to test or
approve.
The Agency notes that the 1994 edition of UL 1322 has the same limits
cited by the commenter, and agrees with the commenter that it is not
realistic to require testing and approval of a product that nationally-
recognized testing laboratories do not test or approve.
Proposed paragraph (p)(5) provided that two-point suspension
scaffolds be securely lashed to the building or structure to prevent
them from swaying. The paragraph further required that window cleaners'
anchors not be used for this purpose. The requirement now appears in
final rule Sec. 1926.451(d)(18) and is applicable to all multi-point
suspended scaffolds. The provision is based on existing
Sec. 1926.451(i)(9).
Final paragraph (p)(5), proposed as paragraph (p)(6), requires that
two-point scaffolds not be bridged or otherwise connected one to
another during raising and lowering operations unless the bridge
connections are articulated and the hoists properly sized. This
paragraph is similar to the proposed paragraph, except for editorial
revisions made for clarity. No comments were received on this
provision.
OSHA notes that paragraph (p)(5) is not intended to prohibit
passage from one scaffold to another, but to prevent significant
overloading of the hoist nearest the bridging device during operation
of the hoist, or displacement of the bridge if the hoist is used to
raise or lower one of the scaffolds. Many hoists are only sized to
support one end of a two-point system. If one of two bridged scaffolds
were to be raised by a hoist, a bridge laid between the scaffolds could
be displaced unless the bridge is articulated (connected). This could
also significantly increase the load on the hoist if it is not properly
sized. The final rule addresses these two hazards by requiring bridge
connections to be articulated and requiring that hoists be properly
sized. These requirements thus allow for properly engineered solutions.
Final rule paragraph (p)(6), identical to proposed paragraph
(p)(7), is a new requirement. It allows passage from one platform to
another only when the platforms are at the same height, when the
platforms abut each other, and when walk-through stirrups specifically
designed for this purpose are used.
Paragraph (q) Multi-point Suspension Scaffolds, Stonesetters' Multi-
point Adjustable Suspension Scaffolds, and Masons' Multi-point
Adjustable Suspension Scaffolds
Paragraph 1926.452(q) of the final rule provides additional
requirements for multi-point suspension scaffolds, stonesetters' multi-
point adjustable suspension scaffolds, and masons' multi-point
adjustable suspension scaffolds. This paragraph combines and clarifies
the provisions of existing Sec. 1926.451(h), stonesetters' adjustable
multi-point suspension scaffolds, and existing Sec. 1926.451(j),
masons' adjustable multi-point suspension scaffolds, and indicates
clearly that paragraph (q) applies to other multi-point adjustable
suspension scaffolds as well.
Paragraph (q)(1) provides that, when two or more scaffolds are
used, they shall not be bridged one to another unless they are designed
to be bridged, the bridge connections are articulated (connected), and
the hoists are properly sized. This paragraph of the final rule, which
is identical to proposed paragraph (q)(1), is based on the same
concerns about displacement of the
[[Page 46088]]
bridge and hoist overloading that resulted in final rule
Sec. 1926.452(p)(5).
Paragraph (q)(2) provides that, if bridges are not used, passage
may be made from one platform to another only when the platforms are at
the same height and are abutting. This provision, which is essentially
identical to that in the proposed rule, is based on the same concerns
that resulted in final rule Sec. 1926.452(p)(6). OSHA has editorially
revised proposed paragraph (q)(2) to delete the word ``closely''
because that word is redundant with the word ``abutting.''
Paragraph (q)(3) requires that scaffolds be suspended from metal
outriggers, brackets, wire rope slings, hooks, or equivalent means.
This provision, which is essentially identical to the corresponding
requirement in the proposed rule, is virtually the same as existing
Sec. 1926.451(j)(4), which addresses stonesetters' adjustable multi-
point suspension scaffolds. OSHA has deleted the word ``iron'' from the
proposed language, based on comments from the SSFI and the SIA (Exs. 2-
367 and 2-368) stating that it is appropriate to have brackets or hooks
fabricated from material other than iron. OSHA agrees with this point
and concludes that employees on these scaffolds will be adequately
protected by brackets or hooks made of other materials, as long as
those components satisfy the strength criteria set in final rule
Sec. 1926.451(a)(1). The final rule reflects this conclusion.
Paragraph (r) Catenary Scaffolds
Paragraph 1926.452(r) of the final rule provides additional
requirements for catenary scaffolds. In OSHA's existing scaffold
standard, catenary scaffolds were addressed only by the general
provisions applicable to all scaffolds. The new provisions in paragraph
(r) thus address specific concerns not directly addressed by the
existing standard. These provisions are identical to proposed
Sec. 1926.452(r).
Paragraph (r)(1) allows no more than one platform to be placed
between consecutive vertical pickups, and no more than two platforms to
be used on a catenary scaffold. These requirements are intended to
prevent overloading of this type of scaffold. This paragraph is
consistent with the corresponding provision of ANSI A10.8-1988,
paragraph 20.4.
Paragraph (r)(2) requires that platforms supported by wire ropes
have hook-shaped stops on each end of the platforms to prevent the
platforms from slipping off the wire ropes. These hooks shall be so
placed that they will prevent the platforms from falling if one of the
horizontal wire ropes breaks. This language is consistent with the
corresponding provision of ANSI A10.8-1988, paragraph 20.1.
Paragraph (r)(3) of the final rule provides that wire ropes shall
not be tightened to the extent that the application of a scaffold load
will overstress them. This provision is consistent with the
corresponding language of ANSI A10.8-1988, paragraph 20.2.
Paragraph (r)(4) requires that wire ropes be continuous and without
splices between anchors. This language is consistent with the
corresponding language in ANSI A10.8-1988, paragraph 20.2, and is
necessary to ensure that the rope has sufficient integrity to handle
the load.
Paragraph (s) Float (Ship) Scaffolds
Paragraph (s) provides additional requirements for float (ship)
scaffolds. These provisions are identical to those in proposed
Sec. 1926.452(s), which were based on existing Sec. 1926.451(w) (3) and
(5).
Paragraph (s)(1) requires that the platform be supported by a
minimum of two bearers, each of which shall project a minimum of six
inches (15.2 cm) beyond the platform on both sides. This will ensure
that the platform will be fully supported. In addition, each bearer
shall be securely fastened to the platform to prevent slippage.
Paragraph (s)(2) provides that rope connections shall be such that
the platform cannot shift or slip. Platform slippage is a significant
factor in scaffold accidents.
Paragraph (s)(3) provides that, when only two ropes are used with
each float, those ropes shall be arranged so as to provide four ends
which are securely fastened to overhead supports, and each supporting
rope shall be hitched around one end of the bearer and pass under the
platform to the other end of the bearer where it is hitched again,
leaving sufficient rope at each end for the supporting ties. This
requirement is necessary to ensure that the supporting ropes are
properly attached to both the platform and to the overhead support to
prevent the scaffold from falling. These requirements are designed to
ensure safe use of these commonly used job-built scaffolds.
Paragraph (t) Interior Hung Scaffolds
Paragraph (t) provides additional requirements for interior hung
scaffolds. These provisions are identical to those of the proposed
paragraph. Paragraph (t)(1) requires that scaffolds be suspended only
from the roof structure or other structural members such as ceiling
beams. This requirement is necessary to ensure that these suspended
scaffolds are supported by structural members with adequate capacity
for safe use. This is the same requirement as existing
Sec. 1926.451(r)(1).
Paragraph (t)(2), which is a new provision, requires that the
supporting members be inspected and checked for strength before the
scaffold is erected. This requirement is necessary because such points
of support cannot be assumed to be strong enough to support a scaffold
since they may already be loaded to their capacity or they may have
deteriorated over time. This provision is consistent with ANSI A10.8-
1988, paragraph 16.7.
Paragraph (t)(3) provides that suspension ropes and cables be
connected to the overhead supporting members by shackles, clips,
thimbles, or by other means which provide equivalent strength, security
and durability. This paragraph of the final rule (identical to the
proposed paragraph) deletes the specific connection requirements of
existing Sec. 1926.451(r)(2), which OSHA determined were obsolete, and
specifies criteria that OSHA has found to be current safe practice. The
strength requirement of existing Sec. 1926.451(r)(2) is now covered by
final rule paragraph Sec. 1926.451(a)(3), which specifies strength
criteria for suspension ropes on all types of scaffolds.
Paragraph (u) Needle Beam Scaffolds
Paragraph (u) of the final rule provides additional requirements
for needle beam scaffolds. These provisions are identical to proposed
paragraph 1926.452(u) except for minor editorial revisions. Paragraph
(u)(1) requires that scaffold support beams be installed on edge. This
provision is based on existing Sec. 1926.451(p)(1), and is necessary to
ensure that support beams are installed in a way that maximizes their
strength.
Paragraph (u)(2) provides that ropes or hangers be used for
supports, except that one end of a needle beam scaffold may be
supported by a permanent structural member. This provision is based on
existing Secs. 1926.451(p)(2) and (8), and is necessary to ensure that
these scaffolds are properly supported by rope or hangers that meet the
strength criteria of Sec. 1926.451(a).
Paragraph (u)(3) requires that the ropes be securely attached to
the needle beams. This is a change from existing Sec. 1926.451(p)(3),
which specified that all rope attachments must be either a scaffold
hitch or properly made eye splices. OSHA determined that the existing
rule is too restrictive, because other knots and means of attachment,
such as wire rope clips, can adequately
[[Page 46089]]
support the scaffold without decreasing employee safety.
Paragraph (u)(4) provides that the support connection be arranged
so as to prevent the needle beam from rolling or becoming displaced,
which could result in tipping of the platform. This provision is based
on existing Sec. 1926.451(p)(4).
Paragraph (u)(5) provides that platform units shall be securely
attached to the needle beams by bolts or equivalent means. In addition,
cleats and overhang are not considered to be adequate means of
attachment. Final rule paragraph (u)(5) clarifies the requirements of
existing Sec. 1926.451(p)(6), which only required that planks be
secured against slipping. Also, under the existing rule, cleats and
overhang could be used to secure the units. As stated in the preamble
to the NPRM (51 FR 42695), OSHA has concluded that cleats or overhang
do not adequately secure platform units to needle beam scaffolds,
because needle beam scaffolds have a tendency to twist, and cleats and
overhangs used to secure platforms will not provide sufficient means of
holding the platforms. This could result in platforms coming loose and
falling.
Paragraph (v) Multi-level Suspended Scaffolds
Paragraph 1926.452(v) of the final rule provides additional
requirements for multi-level suspended scaffolds. These scaffolds are
suspended scaffolds with more than one working level. The provisions of
paragraph (v) are identical to those in the proposed paragraph, except
for minor editorial changes. Although these types of scaffolds are not
specifically addressed in the existing standard, they are covered by
the general requirements in existing Sec. 1926.451. The new provisions
address concerns not covered by the existing standard or by final rule
Sec. 1926.451.
Paragraph (v)(1) requires that multi-level suspended platform
scaffolds be equipped with additional independent support lines, equal
in number to the number of points supported and of equivalent strength
to the suspension ropes, and be rigged to support the scaffold in the
event the suspension rope(s) fail. These additional lines would support
the scaffold, and prevent collapse in the event of primary support line
failure.
Paragraph (v)(2) provides that the independent support lines and
suspension ropes shall not be attached to the same points of anchorage.
This provision reflects OSHA concern that the independent support lines
would not protect workers from scaffold collapse if the independent
lines and the suspension ropes were attached to the same anchorage
point when the anchorage failed.
Paragraph (v)(3) requires that supports for platforms be attached
directly to the support stirrup and not to any other platform. This
provision is intended to protect against platform overloading.
Paragraph (w) Mobile Scaffolds
Paragraph (w) provides additional rules for mobile scaffolds. This
paragraph consolidates and clarifies the provisions of existing
Sec. 1926.451(e) and existing Sec. 1926.453. This paragraph applies to
all mobile scaffolds, not just to those which are manually propelled.
This paragraph of the final rule is effectively identical to that in
the proposed rule, except as discussed below.
Paragraph (w)(1) provides that scaffolds shall be braced by cross,
horizontal, or diagonal braces, or combination thereof, to prevent
racking or collapse of the scaffold and to secure vertical members
together laterally so as to automatically square and align the vertical
members. In addition, scaffolds shall be plumb, level, and squared. All
brace connections shall be secured. This paragraph also provides that
scaffolds constructed of tube and coupler components shall conform to
the requirements of Sec. 1926.452(b) (paragraph (w)(1)(i)), and that
scaffolds constructed of fabricated frame components shall conform to
the requirements of Sec. 1926.452(c) (paragraph (w)(1)(ii)). The
provisions of paragraph (w)(1) are substantively identical to the
corresponding provisions in existing Secs. 1926.451(e)(3) and (e)(9).
Paragraph (w)(2) requires that scaffold casters and wheels be
locked with positive wheel and/or wheel and swivel locks, or equivalent
means, to prevent movement of the scaffold while the scaffold is used
in a stationary manner. This provision is effectively identical to
existing Sec. 1926.451(e)(8).
Paragraph (w)(3) provides that manual force used to move the
scaffold shall be applied as close to the base as practicable, but not
more than five feet (1.5 m) above the supporting surface. This
paragraph is essentially the same as existing Sec. 1926.451(e)(6),
which required that propelling forces be applied as close to the base
as possible. However, the final rule limits the height at which the
force can be applied to 5 feet above the supporting surface, to
minimize overturning forces. One commenter (Ex. 2-23) recommended that
scaffolds not be moved manually unless the propelling force is applied
to the wheels only. Although such a requirement may be appropriate for
powered scaffolds, the Agency sees no rationale for applying this
provision to scaffolds being moved manually. OSHA has not adopted the
suggested change because compliance would be unwieldy and would expose
employees to hazards from the rolling wheels.
The proposed language has been modified in the final rule to
indicate clearly that final paragraph (w)(3) applies only when mobile
scaffolds are being moved manually. This provision is consistent with
ANSI A10.8-1988, paragraph 11.3.1.
Paragraph (w)(4), which is a new provision, requires that power
systems used to propel mobile scaffolds be designed for such use. In
addition, forklifts, trucks, similar motor vehicles, or add-on motors
shall not be used to propel scaffolds unless the scaffold is designed
for such propulsion systems.
Paragraph (w)(5) requires that scaffolds be stabilized to prevent
tipping during movement. This provision is effectively identical to the
corresponding provision in existing Sec. 1926.451(e)(6).
Paragraph (w)(6) provides that employees shall not be allowed to
ride on scaffolds unless the following conditions exist:
1. The surface on which the scaffold is being moved shall be
within three degrees of level, and free of pits, holes, and
obstructions (paragraph (w)(6)(i));
2. The height-to-base width ratio of the scaffold during
movement shall be two to one or less, unless the scaffold is
designed and constructed to meet or exceed nationally-recognized
stability test requirements (paragraph (w)(6)(ii));
3. Outrigger frames, when used, shall be installed on both sides
of the scaffold (paragraph (w)(6)(iii));
4. When power systems are used, the propelling force shall be
applied directly to the wheels, and shall not produce a speed in
excess of one foot per second (0.3 mps) (paragraph (w)(6)(iv)); and
5. No employee is on any part of the scaffold which extends
outward beyond the wheels, casters, or other supports (paragraph
(w)(6)(v)).
These provisions are based in part on the provisions of existing
Sec. 1926.451(e)(7).
Proposed paragraph (w)(6)(ii) set the maximum height-to-base width
ratio at two to one or less. OSHA has revised the proposed provision to
allow a higher ratio when the scaffold is designed and constructed in
accordance with nationally-recognized stability test requirements. This
change is discussed in relation to Issue 4, below.
Proposed paragraph (x)(6)(iv) required that the propelling force be
applied
[[Page 46090]]
directly to the wheels (not to the frame) when power systems are used
to propel scaffolds, and limited the speed of the scaffold to 2 feet
per second. The proposed provision was intended to protect against a
scaffold toppling over should it strike an object.
One commenter (Ex. 2-423) stated as follows:
In our initial testing we tested several speeds including 2'/Sec
and found these to be far too fast for an operator to drive through
narrow areas and through debris that would be encountered on a
construction site. With all the units sold by our company, I have
never had anyone say the Motorized Scaffold (r) was too slow. I
cannot speak for other means of propelling scaffold but we would not
allow our Motorized Scaffold (r) to drive faster than one foot per
second.
OSHA agrees that allowing motor-propelled scaffolds to drive faster
than one foot per second could create problems for operators and has
revised the rule accordingly.
Issue 4 raised a question regarding existing
Sec. 1926.451(e)(7)(ii), which required manually propelled mobile
scaffolds to be not more than twice as high as they are wide when
employees ride on them. The proposed rule, Sec. 1926.452(w), extended
this requirement to cover both manually propelled and motor-propelled
mobile scaffolds. OSHA asked whether the final rule should raise the
current ratio, 2:1, to 3:1 or higher on those systems which are built
with a lower center of gravity, and, if so, what would be appropriate
limitations.
The ACCSH discussed Issue 4 at length (Tr. 48-61, June 9, 1987).
Several members expressed concern about employees riding mobile
scaffolds while the scaffolds were being moved, regardless of the
height-to-base ratio mandated. As OSHA explained to the Committee,
scaffold equipment manufacturers had informed the Agency that a motor
propelled mobile scaffold which exceeded the existing and proposed 2:1
ratio would be safe for use because the attachment of motor units would
lower the center of gravity, thereby increasing the scaffold's
stability (Tr. 52-53). Members of the Advisory Committee questioned the
extent to which the weight of the motor unit would provide sufficient
stability, citing concerns about the manner in which employers would
calculate the height-to-base ratio using the weight of the motor unit
and the extent to which wind or overhead power lines would pose
hazards. Ultimately, the ACCSH voted to recommend simply that OSHA
prohibit riding on mobile scaffolds (Tr. 61).
One commenter (Ex. 2-53) stated that the ``existing rule on
manually propelled mobile scaffolds'' should not be extended to motor-
propelled mobile scaffolds but did not explain why. The AGC commented
(Exs. 2-20, 2-55, and 2-390) that ``[i]n maintaining a performance-
oriented standard, OSHA should provide for manufacturer's
recommendations when movement of a rolling scaffold is required.''
These three comments further stated that OSHA should allow the use of
those mobile scaffolds that have a lower center of gravity and thus
have the capability ``of being moved at a higher ratio.'' Another
participant (Ex. 2-69) commented that ``[W]hen movement of a rolling
scaffold is required, OSHA should provide for use of manufacturers'
recommendations in keeping with a performance-oriented approach.''
One commenter (Ex. 2-70) stated that 3:1 ratio would be acceptable
if the scaffold had a low center of gravity. Another commenter (Ex. 2-
516) added a number of details and factors involved in calculating or
arriving at a safe ``gross ratio'' for mobile scaffolds, and indicated
that ``higher ratios may be permitted in specific instances when
operated under constant and continuous supervision, and when designed
by qualified engineers.'' In particular, the commenter explained that
the 2:1 ratio ``is a minimum standard, established for uniformity,
simplicity, and safety. Higher ratios can easily be achieved in given
instances, but allowing those ratios to be in general use is unwise''
(emphasis in the original). To illustrate the rationale behind this
assertion, the commenter stated, in part, that:
There is a moment in each vertical rolling scaffold leg due to
caster offset. This moment is increased when the wheel is stopped by
a stone or curb, because the tower inertia then acts on the caster
support as a force acting from the center of gravity of the tower,
to the wheel.
The force from the `pushing' and the inertia change depends on
the weight of the scaffold, its velocity, how fast it stops, and how
hard it is being pushed or driven. The moment felt at the scaffold
leg depends on the force, the height of the center of gravity, the
flatness of the rolling surface, whether only one wheel carries the
load, and where on the scaffold it is being pushed.
The height of the center of gravity depends on how much load is
put on top of the scaffold, and the height of the scaffold.
[emphasis in original]
Another commenter (Ex. 2-50) stated that an extension of the ratio
for some scaffolds should not be limited to 3:1. As an example, the
commenter explained that ``some motorized scaffolding, and batteries,
hydraulics, and motors mounted low on the frame are capable of reaching
20-30 feet high with their bases only 6 feet wide.'' The commenter, a
representative from a building contractor's association, added that
``the manufacturers test the machines extensively for upset.''
One commenter (Ex. 2-15) stated ``[e]ven the 2:1 is too permissive
for small, light towers which are usually the most top[-]heavy,
especially with a man on top. This provision is not enforceable. [It
would be] better to forbid riding at all.'' Another commenter (Ex. 2-
29) commented that ``[i]ncreasing the height-to-base ratio of mobile
scaffolds ridden by employees would expose employees to an unacceptable
fall hazard.'' In addition, a commenter (Ex. 2-54) stated that ``2 to 1
is a good ratio, as there is less chance of tipping over and a better
chance for worker[s] to jump off [the] scaffold, and not get hurt, if
[the] scaffold began to tip.'' The SSFI (Ex. 2-367) recommended that
``under no circumstances should the 2:1 height-to-width ratio be raised
to 3:1 for systems built with a `lower center of gravity.' Tipping of
rolling towers is one of the primary causes of accidents and no changes
should be made.''
The SSFI further stated that they have ``always and will continue
to recommend prohibiting riding rolling scaffolds.'' The commenter
noted that ``riding of motor[-]propelled scaffolds is especially
hazardous as the scaffold is normally not designed for such loads.
Motors should not be added to scaffold towers unless the towers are
specially designed to accommodate those forces.'' Another commenter
(Ex. 2-476), also holding the view that riding rolling scaffolds should
not be allowed, recommended that:
Motorized means should not be attached to frame scaffold towers
to promote riding. The 2 to 1 base-to-height ratio, which allows
riding, is not being used by workers riding rolling towers, and
workers are riding rolling towers with any base-to-height ratio. The
scaffold frame rolling towers were not designed to be ridden, and
were not designed for special add-on motors for propulsion.
Another commenter (Ex. 2-13) stated ``[m]obile scaffolds should
never be moved when occupied. The only time they are involved in
accidents is when they are moved while occupied. To allow any but
specifically designed scaffolds to be moved while occupied is totally
unacceptable.''
The SIA (Ex. 2-368) indicated that:
[M]any of our members advocate prohibiting riding of mobile
scaffolds at any time. Others oppose such drastic action, since this
would place undue hardship on those trades which perform a high
percentage of their work on mobile scaffolds. The
[[Page 46091]]
alternative is to develop provisions for their safe use* * * Motors
should not be added to scaffold towers unless the towers are
specifically designed to accommodate the increased forces exerted on
the legs of the scaffold frames.
The SIA (Ex. 2-368) also stated that statistics they had developed over
the past 10 years ``indicate a high incidence of accidents on rolling
scaffolds,'' and that ``[i]t is our position that any raising of the
2:1 ratio would result in increased accidents.''
A commenter (Ex. 2-476) stated that scaffold frames are not
designed for the forces imposed on them by motors that are added on for
propulsion. OSHA agrees with the commenters who raised concerns about
the ability of scaffold frames to accommodate motors and has modified
proposed Sec. 1926.452(x)(6) accordingly.
OSHA agrees with the commenters who indicated that the riding of
some mobile scaffolds can be hazardous. However, OSHA believes that the
rulemaking record supports modification of the current regulations to
allow greater use of mobile scaffolds for this purpose, provided
additional appropriate precautions are taken.
The key concern in specifying the existing 2:1 ratio is stability
of the scaffold. OSHA believes, based on the evidence submitted, that
the existing 2:1 ratio is still the appropriate limit for all manually-
propelled mobile scaffolds and has promulgated final rule paragraph
(w)(6)(ii) accordingly.
OSHA also believes that, given appropriate engineering design,
there are higher ratios which can be used safely on some power-
propelled mobile scaffolds. As recommended by one commenter (Ex. 2-
423), such designs must be proven to be safe, however, by subjecting
the scaffold to stability tests such as the nationally recognized ANSI
A92 tests used by the manufacturers of elevating and rotating work
platforms. Where such tests have not been made, employees are not
allowed to ride the scaffold. This, OSHA notes, does not preclude
manufacturers or others from conducting or establishing such tests to
demonstrate that a product meets appropriate stability criteria. The
Agency believes that equipment meeting such tests and criteria should
be permissible and has promulgated final rule paragraph (w)(6)(iii)
accordingly.
OSHA also believes that compliance with the requirements of
Sec. 1926.451 and final rule paragraph (w)(6)(iv) (that the power be
applied directly to the wheels and that the speed be limited to no more
than 1 foot per second, as recommended by a commenter (Ex. 2-423))
adequately addresses cases where a mobile scaffold is equipped with a
motor.
Paragraph (w)(7), which is identical to the proposed paragraph,
requires that platforms not extend outward beyond the base supports of
the scaffold unless outrigger frames or equivalent devices are used to
ensure stability. Compliance with this provision will prevent eccentric
loading of the scaffold frame that could cause the scaffold to tip
over.
Paragraph (w)(8) provides that, where leveling of the scaffold is
necessary, screw jacks or equivalent means be used. This is a specific
way of complying with Sec. 1926.451(c)(2) of the final rule, which
requires firm, level foundations. This provision is consistent with the
corresponding provision in ANSI A10.8-1988, paragraph 11.1.4.
Paragraph (w)(9) requires that caster stems and wheel stems be
pinned or otherwise secured to scaffold legs or adjustment screws.
Proposed paragraph (w)(9) was identical, except that it did not
specifically provide for the securing of stems to adjustment screws.
This revision is based on input received on this provision from the
SSFI and SIA (Exs. 2-367 and 2-368). OSHA agrees that adjustment screws
provide appropriate attachment points for caster stems and wheel stems,
so that specifically mentioning them in the final rule will clearly
express the Agency's intent and facilitate compliance.
Paragraph (w)(10) provides that, before a scaffold is moved,
employees on the scaffold shall be made aware of the move. This
requirement, which was not part of the proposal, is based on input
received from a commenter (Ex. 2-23) on this section. OSHA agrees with
this input, and has revised the proposed paragraph accordingly. In
addition, OSHA notes that this requirement is consistent with ANSI
A10.8-1988, paragraph 11.2.3.5.
Issue 14 asked whether OSHA should allow mobile scaffolds to move
only along their longitudinal axes while employees are riding on them.
OSHA noted that compliance with this provision, which was suggested by
ACCSH (Ex. 4), would maximize scaffold stability during movement,
because tipping is more likely to occur when a scaffold is moved along
its transverse axis.
Two commenters (Exs. 2-50 and 2-368) stated that such a provision
would be difficult to enforce. Three commenters (Exs. 2-22, 2-53, and
2-368) also stated that this provision would be impractical. The SIA
(Ex. 2-368) went on to explain that:
[S]uch a provision would make it difficult for workers to
perform their duties without violating standards. Sometimes it is
necessary to make even slight adjusting movement of the scaffold in
order to reach the area of work. If workers were prohibited from
moving the scaffold even the slightest amount along the narrow axis,
they would tend to extend their reach over the side of the scaffold,
thus creating an even greater hazard.
Some mobile scaffolds are almost square, which would require a
tape measure to determine when there would be a violation. The
fatigue created by the worker climbing up and down each time he
wished to move the scaffold would tend to increase the likelihood of
an accident.
Another commenter (Ex. 2-50) reasoned that it had never had a
scaffold accident under the existing standards, so it expected that the
proposed requirement would be unreasonably restrictive and difficult to
monitor. Another commenter (Ex. 2-22) foresaw no increase in employee
safety to balance against possible problems encountered by those
required to implement the provisions.
On the other hand, one commenter (Ex. 2-29) simply favored adopting
the suggested provision. Another commenter (Ex. 2-43) agreed that
``rolling scaffolds should be moved in a safe manner'' but added that
``[e]nforcing this requirement will continue to provide special
challenges.''
Five commenters (Exs. 2-13, 2-15, 2-37, 2-54, and 2-367) found the
provision unacceptable, because they felt employees should not be
permitted to ride mobile scaffolds at all. Another commenter (Ex. 2-
308), responding to proposed 1926.452(w), also said that employees
should never be allowed to ride scaffolds. One other commenter (Ex. 2-
13) agreed but added an exception for scaffolds ``that have been
specifically designed for such movement.''
OSHA agrees with the SIA (Ex. 2-368), which indicated that such a
requirement would make it difficult for workers to perform their duties
without violating the standard because it would sometimes be necessary
to make slight adjustments of a scaffold to safely reach the work area.
OSHA is concerned that if workers were prohibited from moving the
scaffold along its transverse axis, even slightly, they would find
themselves in circumstances where they would extend their bodies over
the side of the scaffold to reach a place where they need to perform
work, instead of climbing down the scaffold to reposition it. This
would create a greater hazard because the employee would be at risk of
falling or of tipping the scaffold.
Accordingly, the Agency has not adopted the suggested language in
the
[[Page 46092]]
final rule. OSHA believes the proposed provisions set forth in
Sec. 1926.452(w), Mobile Scaffolds, appropriately address the concerns
of employees riding scaffolds.
(x) Repair Bracket Scaffolds
The March 29, 1993, Federal Register notice reopening the
rulemaking record (58 FR 16509) sought information regarding ``chimney
bracket scaffolds.'' The Agency described such scaffolds as consisting
of platforms supported by brackets which are secured in place by one or
more wire ropes placed in an approximately horizontal plane around the
circumference of the structure and tensioned by a turnbuckle. The
Agency noted that it had recently received information (Exs. 31 and 32)
which suggested that proposed Sec. 1926.451 might not adequately
protect employees on these scaffolds from falls and other hazards.
OSHA noted that it was considering whether specific fall protection
requirements were needed in subpart L for protection of employees on
chimney bracket scaffolds. The Agency also noted that it was
considering the appropriateness of promulgating technical requirements
for chimney bracket scaffolds that are more detailed than those
proposed for scaffolds in general. Accordingly, the March 29, 1993,
Federal Register notice presented a series of questions aimed at
developing criteria for safe use of chimney bracket scaffolds. One
commenter (Ex. 34-35) stated ``[u]nless it can be determined by a
competent person beforehand that the chimney can support a bracket and
an independent safety line and fall protection is used, other means
such as balling, explosives or remote crane suspended hydraulic
attachments should be used.'' OSHA also received substantive input on
chimney bracket scaffolds [repair bracket scaffolds] from one
commenter, the National Advisory Committee for Health & Safety in the
Chimney, Stack, Silo and Natural Draft Cooling Tower Industry (NACHS)
(Ex. 34-33). Those comments are discussed below in relation to the
pertinent provisions of the final rule. The NACHS, a trade association
presenting the experience and views of companies which use the
scaffolds in question, referred to these scaffolds as ``repair bracket
work platforms'' in its comment. Based on that input, the Agency has
determined that the term ``repair bracket scaffold'' should be used in
place of the term ``chimney bracket scaffold.''
The NACHS (Ex. 34-33) indicated that a ``repair bracket scaffold''
is a type of supported scaffold that has been used safely for over 80
years for tuckpointing on brick chimneys; crack repairs; the
installation of bands on brick or concrete chimneys; painting; access
to caps, hoods, and lightning protection systems; installation of
permanent platforms; piece-meal demolition of brick, concrete, and
steel chimneys; waterproofing brick and concrete chimneys; 360 degree
access at any given elevation for any activity; and steeple access.
According to the commenter, these scaffolds are installed by encircling
a structure with a minimum one-half-inch diameter wire, tensioned by a
minimum one-inch turnbuckle. Brackets are then placed over the wire
rope, and scaffold planking (12-inch minimum width), guardrail posts
and handrails are installed on the brackets.
Based on the information received, OSHA again reopened the
rulemaking record (59 FR 4615, February 1, 1994) to solicit comment on
draft regulatory text that the Agency was considering for inclusion in
the final rule. In addition, the Agency noted that it was considering
whether employees working on chimney bracket scaffolds needed to be
protected from fall hazards by both a ``Type I'' guardrail, as would
have been required by proposed Sec. 1926.451(e)(4), and a personal fall
arrest system. Also, OSHA noted that it was considering what provisions
must be made for rescue of employees from chimney bracket scaffolds in
the event of scaffold collapse or a medical emergency. The Agency
indicated that it was developing criteria for employers who would need
to comply with these provisions. As is discussed below in relation to
the provisions of final rule paragraph (x), the Agency also raised
Items (a) through (l) for consideration as prospective provisions of
the final rule. (All references to Items and Issues in this paragraph
of the preamble relate to the February 1, 1994 reopening notice.) The
one commenter, Monsanto, (Ex. 43-45) who responded to those Items
stated that they should be adopted in the final rule.
Based on the rulemaking record, OSHA has determined that it is
appropriate to add a new paragraph (x) to Sec. 1926.452 to address the
use of `repair bracket scaffolds'. In addition, a definition of that
term, based on the NACHS comment, is being added to Sec. 1926.450(b),
Definitions.
Paragraph (x)(1) requires employers to secure brackets in place
with \1/2\ inch diameter wire rope that extends around the
circumference of the chimney. This provision, which incorporates the
language from Items (a) and (b) of the February 1, 1994 notice (59 FR
4617), codifies established good industry practice as described by the
NACHS (Ex. 34-33).
Final rule paragraph (x)(2) requires that each bracket be attached
to the securing wire rope (or ropes) by a positive locking device
capable of preventing the unintentional detachment of the bracket from
the rope, or by some other means which prevents unintentional
detachment. The NACHS (Ex. 34-33) indicated that brackets are
positioned on the cable in the course of erecting the scaffold. Issue 6
asked if OSHA should require a positive locking device on the bracket
hook that is placed over the wire rope to prevent unintentional
separation of the bracket from the wire rope. Continental Chimney Inc.
(CCI) and NACHS (Exs. 43-1 and 43-21) supported such a requirement.
Final rule paragraph (x)(3) requires that each bracket, at the
contact point between the supporting structure and the bottom of the
bracket, be provided with a ``shoe'' (heel block or foot) capable of
preventing the lateral movement of the bracket. Issue 7 asked if OSHA
should incorporate such a requirement in the final rule. CCI and NACHS
(Exs. 43-1 and 43-21) commented that a ``shoe'' was needed to prevent
lateral movement. In addition, CCI stated ``The bottom of our [bracket]
feet have an angle cut into them to prevent them from getting caught up
on obstructions on the chimney and becoming disconnected if the
scaffold system should slip.''
Final rule paragraph (x)(4) requires that platform units be secured
to brackets in a manner that prevents the separation of platform units
from brackets and prevents movement of platform units or brackets on a
completed scaffold. This provision is based on Item (e), which provided
that platform units shall be secured to the brackets. Issue 4 asked how
employers should fasten platform units to brackets so that they do not
inadvertently detach. CCI (Ex. 43-1) stated ``We have used \1/8\''
cable with \1/4\'' rope. \1/4\'' rope is enough most of the time. The
\1/8\'' cable provides added security and can be secured adequately be
tying it in right along side the \1/4\'' rope. Using clamps here would
never work.'' The NACHS (Ex. 43-21) responded that employers should
secure platform units to brackets ``[b]y any positive system available,
i.e., wire, rope, etc.'' OSHA has determined that it is appropriate to
allow employers flexibility in choosing the means of securing platform
units and has added final rule paragraph (x)(4) accordingly.
Final rule paragraph (x)(5) provides that, when a wire rope is
placed around
[[Page 46093]]
a structure to provide safe anchorage for personal fall arrest systems
that are used by employees erecting or dismantling repair bracket
scaffolds, the wire rope shall be at least \5/16\ inches in diameter
and shall, in all other respects, satisfy the requirements of subpart
M, OSHA's Fall Protection Standard. This paragraph, which is
effectively identical to Item (l) of the February Notice, codifies
established good practices as described by the NACHS (Ex. 34-33).
Final rule paragraph (x)(6) requires that each wire rope used for
securing brackets in place or as an anchorage for personal fall arrest
systems be protected from damage due to contact with edges, corners,
protrusions, or other discontinuities of the supporting structure or
scaffold components. Issue 10 of the Reopening Notice asked how
employers protected wire ropes from abrasion. CCI (Ex. 43-1) stated
``Our brackets hold the cable 3'' below our decking.'' The NACHS (Ex.
43-21) responded ``[t]he bracket scaffold support cable is static, and
abrasion experienced from * * * installation does not affect its
integrity. The hardwood cable block spacers (@ [+ or -] 36'' centers)
minimize and often prevent the cable from making contact with the
structure's surface.'' OSHA has determined, based on the comments, that
adequate means of protecting wire rope from abrasion are readily
available to affected employers.
Final rule paragraph (x)(7) provides that tensioning of each wire
rope used for securing brackets in place or as an anchorage for
personal fall arrest systems shall be by means of a turnbuckle at least
1 inch in diameter, or by some other equivalent means. This paragraph,
which is very similar to Item (b) of the Reopening Notice, codifies
established good practice as described by the NACHS (Ex. 34-33). OSHA
has allowed employers the flexibility to use means other than a single
turnbuckle for tensioning wire ropes, where the alternative means
provide equivalent tension, because the Agency wants to encourage
innovation and provide flexibility. In addition, OSHA anticipates,
based on information from NACHS (Ex. 34-33), that there may be
circumstances where more than one turnbuckle will be needed to tension
the wire rope, depending on the diameter of the chimney.
Final rule paragraph (x)(8) requires that each turnbuckle be
connected to the other end of its rope by use of a proper-size
eyesplice thimble. Issue 8 of the February Notice asked if OSHA should
add such a requirement to the final rule. CCI (Ex. 43-1) stated
``Thimbles are very helpful in keeping the cable in good condition.
These can be fit over the turn buckle eye and then closed back up.''
Also, the NACHS (Ex. 43-21) commented that OSHA should add a
requirement for the use of a proper size thimble.
Final rule paragraph (x)(9) provides that U-bolt wire rope clips
shall not be used on any wire rope used to secure brackets or to serve
as an anchor for personal fall arrest systems. OSHA expressed concern
in the February 1, 1994 reopening notice that the use of U-bolt wire
rope clips as wire rope fasteners on the horizontal support ropes could
result in damage to the dead end of the rope. Further, if a segment of
damaged dead end later were to become part of the live end due to an
increase in the circumference of the structure, the Agency was
concerned that the wire rope would be unable to support the loads
imposed on it.
CCI responded (Ex. 43-1) ``The use of U wire rope clips does not
damage the wire rope significantly when they are not over-tightened.
Double-saddle clips are not as strong as U wire rope clips and are
difficult to put on the cable.'' Also, Charles Greene (Ex. 43-47), a
safety consultant, stated he ``[w]ould recommend that fist or saddle
clips be used to fasten the horizontal support ropes that support the
bracket scaffolds.''
OSHA disagrees with CCI regarding the safety of using U-bolt wire
rope clips, based on the Agency's review of Rosnagles Handbook of
Rigging and the Wire Rope User's Handbook. The information in those
publications clearly indicates that the use of U-bolt wire rope clips
could significantly damage wire ropes. Where wire rope is used to
secure brackets, U-bolt clips shall not be used because a segment of
damaged dead end could later become part of the live end due to an
increase in the circumference of the structure. By contrast, the
standard allows U-bolts in other applications, such as where the U-bolt
is used at the end (dead end) of the wire rope and that part of the
wire rope is never moved into the live section. Accordingly, because of
the risk of damaging the wire rope, OSHA is prohibiting the use of U-
bolt wire rope clips on repair bracket scaffold support cables.
Final rule paragraph (x)(10) requires employers to ensure that
materials are not dropped to the outside of the supporting structure.
This paragraph is based on Item (j) of the February Notice. In
addition, Issue 2 of the Reopening Notice asked if requirements other
than those in proposed Sec. 1926.451(f) (Sec. 1926.451(h) of the final
rule) were needed to address the hazards of materials falling to the
outside of the structure. The NACHS (Ex. 34-33) indicated that chunks
of material generated during demolition operations are ``dropped
piecemeal down the inside of the chimney and kept off the scaffold.''
There was no response to Issue 2. OSHA believes that this requirement
simply codifies existing good industry practice and provides an
appropriate supplement to the provisions of final rule
Sec. 1926.451(h).
Final rule paragraph (x)(11) requires that erection of a repair
bracket scaffold be performed in only one direction around the
structure. This provision is based on item (k); as with the other
``items'' from the February 1, 1994 notice, the Agency believes that
this paragraph simply codifies established good industry practice.
In addition, the February 1, 1994 reopening notice raised several
Issues and Items which did not result in the addition of requirements
to the final rule. For example, Reopening Issue 1 asked how employers
would provide a safe anchorage point for personal fall arrest systems
and whether compliance with the General Industry standard for powered
platforms, Sec. 1910.66, Appendix C would be appropriate. The NACHS
(Ex. 43-21) stated that a wire rope anchorage point could be attached
to a structure ``by means of tensioning devices i.e., turnbuckles and
hardwood cable spacer (stand off) blocks.'' The commenter also stated
that conformance with Sec. 1910.66, Appendix C, should not be required
``because the chimney bracket scaffold erector is secured to an
independent anchor (ladder) during the installation process.'' Based on
this information, OSHA has not added the cross-reference to the General
Industry standard to the final rule.
In addition, Item (i) provided for a competent person to inspect
the supporting structure before scaffold erection begins, and Issue 3
asked what criteria a competent person should apply when inspecting the
supporting structure. The NACHS (Ex. 43-21) stated that the criteria
should be determined by the ``competent person'' (as defined in
existing Sec. 1926.32(f)) and ``should be the responsibility of each
contractor on a project by project basis.'' Charles Greene (Ex. 43-47)
stated that OSHA should require inspection of wire rope before each
use. The Agency believes that compliance with the general requirements
in final rule Sec. 1926.451(f)(3), which provides that a competent
person shall inspect scaffolds (including supporting structures and
anchorage points) for visible defects prior to each work shift and
after any occurrence that could affect the
[[Page 46094]]
scaffolds' structural integrity, will provide adequate assurance that
unsafe scaffolds are not used. Accordingly, the Agency has not added
additional specific criteria for inspection of repair bracket scaffolds
to the final rule.
Reopening Issue 3 sought comment on the use of a wire rope placed
at the platform level in lieu of an inner guardrail system on tank
builders' scaffolds. The Steel Tank Institute (STI) (Ex. 43-5) stated:
One STI member uses a fabricated hook with an eyelet for
attaching a safety lanyard and harness. The hook is hooked over the
top plate of steel on the tank being erected. This system allows a
high degree of mobility for workers since the hook can slide
horizontally along the steel plate, and results in 100% fall
protection. If such a system is used, the space between the scaffold
planks and the tank shell should not be an issue.
OSHA believes that, in general, the use of guardrail systems or
personal fall arrest systems would provide more effective protection
than the system described by the STI. The Agency also believes,
however, that the method described by this commenter to use personal
fall arrest systems could be used in many cases to provide protection
equivalent to the wire rope guardrail described in Issue 3.
Reopening Issue 5 asked what criteria, if any, should be set for
brackets used with repair bracket scaffolds. CCI (Ex. 43-1) stated that
there was ``no need'' to set such criteria. In addition, the NACHS (Ex.
43-21) responded ``[n]o criteria should be set by OSHA that may
restrict material and system improvements that are in constant change
due to modern technology.'' The Agency agrees that it is important to
encourage development of improved systems and materials. Furthermore,
OSHA believes that compliance with the requirements in final rule
Secs. 1926.451 (a), (b) and (c), will ensure that brackets used on
repair bracket scaffolds provide adequate protection for employees.
Accordingly, the Agency has not added specific criteria for brackets to
the final rule.
Reopening Issue 9 asked whether the safety factor for wire rope
used with repair bracket scaffolds should be 4:1, as recommended by the
NACHS (Ex. 34-33), or 6:1, as provided in proposed Sec. 1926.451(a) and
in Item (d). OSHA noted that a 4:1 safety factor might be inadequate
because the use of wire rope clips reduces the strength of the rope.
The NACHS (Ex. 43-21) stated ``[t]he Committee unanimously recommends a
safety factor of 4:1 be satisfied.'' OSHA believes that the strength of
wire ropes used with repair bracket scaffolds is just as important as
the strength of ropes used with other scaffolds. Therefore, the Agency
has determined that the 6:1 safety factor which OSHA has set as a
general requirement for wire ropes (final rule Sec. 1926.451(a)) is
also appropriate for wire ropes used with repair brackets.
Reopening Issue 11 asked if OSHA should specify that each platform
unit on a chimney bracket scaffold shall extend at least 12 inches over
its supports, as recommended by NACHS (Ex. 34-33) and provided by Item
(f), or extend at least 6 inches (unless cleated or otherwise
restrained) as provided by proposed Sec. 1926.451(b). CCI (Ex. 43-1)
stated that platform units should extend out at least 12 inches. The
NACHS (Ex. 43-21) stated that OSHA should require minimum extension of
6 inches unless cleated or otherwise restrained as provided by proposed
Sec. 1926.451(b), but did not explain why it had changed its position.
OSHA believes that compliance with the 6-inch requirement as set forth
in final rule Sec. 1926.451(b)(4) will adequately protect employees
working on repair bracket scaffolds.
Items (c) and (h) would have incorporated strength and guardrail
requirements into paragraph (x). These provisions are not needed
because the general requirements in final rule Sec. 1926.451 (a) and
(g) adequately address scaffold capacity and fall protection.
Item (g) provided that the span of platform units from bracket to
bracket shall not exceed 5 feet on the outside of the brackets. As
noted above, Monsanto (Ex. 43-45) supported the inclusion of this
provision in the final rule. The Agency notes that while span is a
factor, the issue is already addressed by the general requirements for
minimum and maximum overhang (final rule Sec. 1926.451(b)(4) and (5)),
and the capacity requirements of Sec. 1926.451(a). There is thus no
need to add this requirement to the final rule.
Paragraph (y) Stilts
Final rule paragraph (y) provides requirements for the use of
stilts. Neither OSHA's existing scaffold standard (subpart L) nor the
proposed rule directly addressed the use of stilts. NPRM Issue 20 asked
if OSHA should prohibit or regulate the use of stilts. In particular,
the Agency requested suggestions as to the appropriate construction and
use of stilts, fall protection for employees wearing stilts, floor
conditions in areas where stilts are being used, and other necessary
considerations.
The SSFI (Ex. 2-367) stated that they ``would support OSHA's
prohibition on using stilts while undertaking work on scaffolds'' as
this ``would be considered unsafe.'' Another commenter (Ex. 2-29)
stated, ``stilts are not recommended for construction conditions.
Unlevel working surfaces, debris, etc. are particular problems when
using stilts.''
On the other hand, a commenter (Ex. 2-13) stated, ``OSHA should not
prohibit the use of stilts. They have been used safely for many years.
They should never be used near any unprotected opening.'' The SIA (Exs.
2-368, 5a-16) agreed that the Agency should promulgate a rule
permitting the use of stilts but should spell out ``some safety rules,
particularly when their use places the worker at heights above the
standard guardrail protection.'' Many commenters on Issue 20 used a
specific height (length) of no more than 40 inches as a cut off point
above which they considered the use of stilts to be unsafe (Exs. 2-47,
2-61, 2-63, 2-67, 2-78, 2-156, and 2-304).
Over 460 other commenters expressed the view that Issue 20 was the
first step towards a prohibition on the use of stilts. Those comments
stated that prohibiting the use of stilts would cause employees to
sustain injuries from over-reaching and falling from ladders, stools,
platforms, homemade benches, boards, inverted buckets and other devices
they would otherwise use to elevate themselves when doing painting,
finishing or ceiling work. In particular, one commenter (Ex. 2-99)
stated
Based on our experiences over these many years, we have found
stilts to be a very safe and effective means to perform work in a
timely and efficient and safe manner. Whenever stilts are used on a
project, we have found that general housekeeping improves. There is
much less debris found even on a short term basis than there would
be with conventional scaffolding. We are able to use stilts to reach
areas where conventional scaffolding and even ladders would be
unsafe due to jobsite conditions. We do not let just any employee
work on stilts. Our safety record attests to that. During the twenty
(20) years we have used stilts, we have only had two (2) accidents
involving the stilts--and both of these accidents were by the same
employee.
Most of the commenters stressed the need for proper training for
employees who use stilts (Exs. 2-6, 2-301, 2-379, and 2-406B). Most of
the comments also indicated that some safety provisions, such as debris
control, are needed if stilts are to be used.
Based on the concerns expressed by commenters, Issue L-4 of the
hearing notice (53 FR 2048, January 26, 1988) set out four provisions
that OSHA was considering for inclusion in the final rule for subpart L
and solicited public input. Final rule Secs. 1926.452(y)(1) and (2)
address the use of stilts on large area
[[Page 46095]]
scaffolds, and Secs. 1926.452 (y)(3) and (4) provide criteria for the
use of stilts in general. These are based on the first through fourth
provisions, respectively, raised in Hearing Notice Issue L-4.
The Association of the Wall and Ceiling Industries International
testified (Tr. 3/22/88, p. 86, Ex. 5a-14) in favor of the proposed
provisions. The SIA testified that stilt use was widespread and that
stilts were considered a useful tool by the ceiling and wall industries
(Tr. 3/22/88, pp. 157-158). The SIA testimony supported three
provisions that OSHA is adopting, but did not express an opinion on the
fourth provision (final paragraph (y)(2)).
Paragraph (y)(1) requires that employees not wear stilts on
scaffolds except when the employees are on large area scaffolds. This
paragraph is effectively identical to the language in the first
provision raised for consideration in Issue L-4.
Paragraph (y)(2) provides, when employees wearing stilts are on
large area scaffolds where guardrail systems are being used, that the
dimensions of the guardrail system shall be increased to offset the
height of the stilts. This paragraph corresponds to the language in the
second provision raised for consideration in Issue L-4.
The SIA (Ex. 2-368) commented that a standard providing for the use
of stilts on scaffolds should address guardrail height on scaffolds
where stilts are being used.
Paragraph (y)(3) of the final rule provides that all surfaces on
which stilts are used shall be flat and free of pits, holes and
obstructions, such as debris, as well as all other tripping and falling
hazards. This paragraph is identical to the language in the third
provision raised for consideration in Issue L-4.
Many commenters noted the importance of removing potential tripping
hazards where stilts are used (Exs. 2-54, 2-71, 2-99, 2-149, 2-166, 2-
205, 2-219, 2-256, 2-272, 2-283, 2-295, 2-307, and 2-324). For example,
a commenter (Ex. 2-54) stated:
It would seem those that would have the opportunity to use
stilts the most would be stepping into a lot of loose debris that
has fallen and quite vulnerable to injury from slipping and falling.
Paragraph (y)(4) of the final rule provides that stilts shall be
properly maintained and that any alterations of the original equipment
must be approved by the manufacturer. This paragraph is identical to
the language in the fourth provision raised for consideration in Issue
L-4.
Several commenters who responded to Issue 20 addressed the
condition of stilts. Those commenters (Exs. 2-59, 2-62, 2-71, 2-72, 2-
108, 2-211, 2-219, 2-237, 2-243, 2-301, 2-304, 2-304, 2-313, 2-324, 2-
379, 2-406B, and 2-409), generally, indicated that requirements for
proper maintenance and inspection of stilt equipment, including straps
and fittings, were needed. A number of manufacturers, contractors, and
workers who use stilts also expressed strong approval for the use of
manufactured stilts (as opposed to the use of job-made stilts) (Exs. 2-
47, 2-127, 2-154, 2-257, 2-304-25, and 2-411A). The Agency has no
information which indicates that job-made stilts pose a greater hazard
than manufactured stilts, and therefore is not covering them
differently under this paragraph. OSHA will monitor work experience
under this provision to determine if it is appropriate to treat
manufactured and job-built stilts differently.
Section 1926.453 Aerial Lifts
OSHA proposed to delete existing Sec. 1926.451(f), Elevating and
rotating work platforms, because the Agency believed that the existing
provision was redundant with existing Sec. 1926.556, Aerial lifts,
which is in subpart N, Cranes, Derricks, Hoists, Elevators and
Conveyors, of the Construction Standards. Existing Sec. 1926.451(f)
provides only that employers comply with ANSI A92.2-1969, Vehicle
Mounted Elevating and Rotating Work Platforms. This requirement is also
found in Sec. 1926.556. Section 1926.556, in turn, sets some specific
requirements for specified lift operations, but primarily references
ANSI A92.2-1969.
The SIA (Ex. 2-368) objected to the proposed deletion, stating that
equipment which falls under the definition of ``scaffold'' should be
addressed by subpart L. ANSI A92.2-1969 classifies elevating and
rotating work platforms as ``scaffolds.''
Based on consideration of the comment, OSHA believes that the
retention of existing Sec. 1926.451(f) would not be appropriate.
However, the Agency agrees with the commenter that this type of
equipment is a scaffold and that it should be addressed by subpart L.
In order to facilitate the efforts of construction employers to
safeguard employees who use elevating and rotating work platforms, the
Agency has decided to move the requirements of Sec. 1926.556 to a new
Sec. 1926.453, Aerial lifts, in subpart L. The introductory text to
this section indicates that Sec. 1926.453 applies only to ANSI A92.2
type equipment (vehicle mounted elevating and rotating work platforms),
and further notes that the requirements of Sec. 1926.451 and
Sec. 1926.452 do not apply to this type of equipment.
In addition, OSHA recognizes that the A92 Committee has updated
A92.2-1969 and has adopted other A92 standards which address
technological advances and evolving safe industry practices regarding
elevating and rotating work platforms. The Agency has determined that
compliance with the pertinent A92 standards adopted by ANSI since 1969
will provide employee safety at least equivalent to that attained
through compliance with ANSI A92.2-1969. Accordingly, OSHA is providing
a list of post-1969 ANSI A92 standards which are presently available,
and is placing this list in a new non-mandatory Appendix C to this
standard (subpart L). This non-mandatory appendix can be updated as
necessary to include future revisions of the A92 standards or other
relevant information.
Paragraph (a) addresses general requirements for aerial lifts,
while paragraph (b) contains specific requirements for this equipment.
Paragraph (b)(1) through (b)(5) specify requirements for ladder trucks
and tower trucks, extensible and articulating boom platforms,
electrical tests, bursting safety factors, and welding standards for
aerial lifts, respectively
Section 1926.454 Training Requirements
Section 1926.454 addresses training for employees working with
scaffolds. The introductory text indicates clearly that this section
both supplements and clarifies the training provisions in existing
Sec. 1926.21(b)(2). That standard, which applies to all construction
work, requires employers to ``instruct each employee in the recognition
and avoidance of unsafe conditions and the regulations applicable to
his work environment to control or eliminate any hazards or other
exposure to illness or injury.'' While that language clearly
articulates the employer's general duty to provide training, OSHA
believes it is appropriate to provide more specific direction regarding
the training necessary for employees who work on scaffolds.
Accordingly, Sec. 1926.454 sets certain criteria allowing employers to
tailor training to fit their workplace circumstances.
The introductory text of proposed Sec. 1926.460 indicated that OSHA
would cite employers for violations of the added training requirements
in this section only when a citation was issued concurrently under the
provisions of proposed Secs. 1926.450, 1926.451 or 1926.452. However,
it is clear to OSHA that this approach is not appropriate and does not
provide adequate
[[Page 46096]]
employee protection, because the training of an employee does not
necessarily ensure that an employee will follow the substantive safety
provisions of the standard in every case.
OSHA's enforcement of the standard's training requirement does not
depend on the extent to which an employer is fulfilling other
compliance obligations under subpart L. In this regard, the scaffold
standard is like any other OSHA standard that provides for both hazard
prevention and employee training. The employer has separate duties to
provide protection and to train employees, and may be cited for
violating either or both types of requirements.
Paragraph (a) of the final rule sets training requirements for
employers who have employees working on scaffolds. The introductory
text requires employers to ensure that each employee whose employment
involves being on a scaffold is trained to recognize the hazards
associated with the type of scaffold being used and to understand the
procedures which must be followed to control or minimize those hazards.
Proposed paragraph (a) required that all employees using scaffolds
to perform a job task be instructed in the proper construction, use,
placement and care of the scaffolds they are using, and in the
applicable provisions of this subpart. OSHA has determined that the
proposed provision should be revised to provide more specific direction
regarding how employees working on scaffolds are to be trained. In
addition, the Agency recognizes that it is appropriate to distinguish
between the training needed by employees erecting and dismantling
scaffolds and the training needed by employees who are on scaffolds in
the course of their work. Accordingly, final rule paragraph (a)
addresses employees who are working on scaffolds and final rule
paragraph (b) addresses employees who are erecting and dismantling
scaffolds. OSHA anticipates that some employees, such as those who use
adjustable suspension scaffolds, will need training that complies with
both paragraph (a) and paragraph (b).
The SIA and the Duke Power Company (Exs. 2-368 and 2-465) commented
that employees who use scaffolds do not need to know how to construct,
place, and care for these scaffolds. The SIA (Ex. 2-368) stated ``Does
every single worker on the job need to know how the scaffold is
constructed, or how it was placed, or how it is to be cared for? This
should be the responsibility of some ``competent'' person, but not
everyone on the scaffold.'' In addition, Duke Power (Ex. 2-465) noted
``the majority of scaffolds used are not constructed by the employees
using them.'' As noted above, OSHA agrees with these concerns and final
rule Sec. 1926.454 reflects this thinking.
The introductory language of final rule paragraph (a) also requires
employers to ensure that each affected employee has been trained by a
person who is qualified in the pertinent subject matters. The
requirement for training by a qualified person has been added to the
final rule to ensure that the training is adequate. The ACCSH (Tr. 6/9/
87, p. 266) recommended that OSHA require the involvement of a
competent person in the program to provide appropriate assurance that
employees will be adequately trained. However, the Agency has decided
that a qualified person would be more appropriate because it is the
knowledge, skill or experience of the trainer, not the trainers
authority, which determines the adequacy of the training provided.
Limiting the delivery of the required training only to a competant
person would prevent employers from taking advantage of outside sources
of training, such as scaffold manufacturers and suppliers, that
regularly provide these types of services to clients.
Paragraphs (a)(1) through (a)(5) address five areas in which
training must be provided, as applicable. Final rule paragraph (a)(1)
requires that affected employees be trained in the nature of any
electrical hazards, fall hazards and falling object hazards in the work
area. Many employees have been killed or seriously injured because they
were unaware of workplace hazards or did not understand the
consequences of exposure to those hazards. This provision clearly
indicates the hazards (i.e., electrocution, falls and falling objects)
regarding which training must be provided. This paragraph elaborates on
the requirements of existing Sec. 1926.21(b)(2), which addresses
training in the general recognition and avoidance of hazards.
Final rule paragraph (a)(2) requires that affected employees be
trained in the correct procedures for protection from electrical
hazards and for erecting, maintaining, and disassembling the required
fall protection systems and falling object protection systems.
Employees who are on scaffolds while working need to know how
protective systems function, so that they know how to install, maintain
or remove these systems, as necessary. For example, where a scaffold
has been erected without the protective measures necessary for work to
be performed on or from the scaffold, the employees subsequently coming
onto the scaffold would need to install them. Even where the scaffold
erectors have installed the required protection for affected employees,
the employees working on the scaffold need to know when and how to
maintain that protection, so that a hazardous situation does not
develop during scaffold use. Proposed paragraph (a) addressed this
subject only in general terms.
The ANSI Z359 Committee stated (Ex. 2-57)
``[P]ersons who work on scaffolds should be required to undergo
fall protection training. This is not specified in sufficient detail
in 1926.460. The content, specificity and training environment for a
fall protection training program should perhaps be considered as the
subject of a national standard.'' OSHA agrees with this comment and
has revised the proposed training provision accordingly.
Paragraph (a)(3) requires that employees be trained in the proper
use of the scaffold and in the proper handling of materials on the
scaffold. This paragraph is effectively identical to the corresponding
provision of proposed paragraph (a). The language regarding the proper
handling of materials has been added to facilitate compliance with the
requirements for falling object protection.
Paragraph (a)(4) requires that employees be trained in the maximum
intended load and the load-carrying capacities of the scaffolds used.
This language is effectively identical with the corresponding language
of proposed paragraph (a).
Paragraph (a)(5) requires that employees be trained in the
pertinent requirements of subpart L. This provision is effectively
identical to the corresponding language in proposed paragraph (a).
Paragraph (b) of the final rule addresses training for employees
assembling, maintaining or dismantling scaffolds. The introductory
language of paragraph (b) requires that the employer have each employee
who erects, disassembles, moves, operates, repairs, maintains, or
inspects a scaffold trained by a competent person so that the employee
can recognize any hazards related to such work duties. This provision
is effectively identical to the language in proposed paragraph (a). As
noted above, final rule paragraph (b) is designed to differentiate
clearly between the training needed by employees erecting and
dismantling scaffolds and the training needed by employees who are on
scaffolds in the course of their work. In addition, this provision
corresponds, in part, to the language in proposed paragraph (b), which
required that employees repairing scaffolds be
[[Page 46097]]
competent individuals ``trained and familiar with the design criteria,
intended use, and the proper procedures for repairing the defective
component(s).''
The introductory language of final paragraph (b) requires the
employer to ensure that each affected employee has been trained by a
competent person in four areas, as applicable. As discussed above in
relation to final rule Sec. 1926.454(a), OSHA has added this
requirement in response to a recommendation from the ACCSH (Tr. 266, 2/
9/87).
Paragraph (b)(1) requires that affected employees be trained in the
nature of scaffold hazards. This provision effectively restates the
existing Sec. 1926.21(b)(2) requirement that employees be instructed in
the recognition and avoidance of unsafe conditions.
Paragraph (b)(2) requires that affected employees be trained in the
correct procedures for erecting, disassembling, moving, operating,
repairing, inspecting, and maintaining the type of scaffold in
question. This language, which is consistent with the corresponding
language in proposed paragraphs (a) and (b), indicates clearly that
training must address the particular type(s) of scaffold with which
each affected employee will be working. Training provided to an
employee to construct, repair or dismantle one type of scaffold will
not necessarily enable that employee to repair another type.
Paragraph (b)(3) requires that affected employees be trained in the
design criteria, maximum load-carrying capacity, and intended use of
the scaffold. This provision is consistent with the corresponding
language in final rule paragraph (a)(4).
Final rule paragraph (b)(4) requires that affected employees be
trained in the pertinent requirements of subpart L. This provision,
like final rule paragraph (a)(5), is effectively identical to the
corresponding language in proposed paragraph (a).
Non-mandatory Appendix D lists various training topics that may be
important for the employers and employees erecting or dismantling
scaffolds. The list is not all-inclusive, and OSHA is providing it
solely as informational guidance. The employer may need to address
topics or situations not mentioned in the Appendix which are specific
to the employer's particular circumstances.
Proposed paragraph (c), which addressed training specifically for
employees who operate suspended scaffolds, has been deleted from the
final rule, because the Agency has determined that training for these
employees is adequately covered by the requirements in paragraphs (a),
(b) and (c) of the final rule.
Final paragraph (c) requires the employer to retrain any employee
when the employer has reason to believe that the employee does not have
the understanding and skill required by paragraph (a) or (b) of this
section. Employees must be retrained, as necessary, to restore the
requisite scaffold-related proficiency. Circumstances where the
provision requires retraining include, but are not limited to, the
following situations: first, whenever there is a change at the worksite
that presents a hazard about which the employee has not been trained
(paragraph (c)(1)(i)); second, where changes in the types of scaffolds,
fall protection, falling object protection, or other equipment present
a hazard about which the employee has not been trained (paragraph
(c)(1)(ii)); and, third, where inadequacies in an affected employee's
work practices involving scaffolds indicate that the employee has not
retained the requisite proficiency (paragraph (c)(1)(iii)). This
provision simply clarifies the language of proposed Sec. 1926.460(d),
which stated that employees would receive training and retraining as
necessary. OSHA notes that this provision is essentially identical to
the corresponding retraining requirements in the Construction Industry
fall protection standard (Sec. 1926.503(d)) and the General Industry
standards for permit-required confined spaces (Sec. 1910.146(g)(2)) and
personal protective equipment (Sec. 1910.132(f)(3)).
NPRM Issue 15 solicited comments regarding employee training and
retraining on scaffold use. In particular, OSHA asked for data on the
costs and effectiveness of training requirements in reducing the risk
of injuries or fatalities, and whether more or less specific
requirements were appropriate. Commenters were also asked to provide
the Agency with information about currently available safety programs
and their adequacy; the safety records of employees who have been
trained; the scope and necessary elements of training programs; the
relationship of the additional specific provisions in proposed
Sec. 1926.460 to the more general Sec. 1926.21 requirements; the costs
and benefits of these provisions; and possible recordkeeping burdens
these provisions might involve.
The SIA (Ex. 2-368) stated: ``[T]he SIA devotes a considerable
portion of its budget to promotion of safety and training through
audio-visual programs and training courses for the safe use of
scaffolds. We believe that training will reduce accidents and would
like to see some additional requirements in the scaffold standards.''
However, the SIA expressed concern that employers would have to
``establish and maintain extensive records on each employee'' because
the rule would expose them to ``increased liability from an insurance
standpoint'' and to OSHA citations. The SIA also indicated that
training would not be able to cover all foreseeable equipment use, and
that an employer who assumed that training was all-encompassing would
be compromising the safety of its employees. Furthermore, the SIA
stated that the proposed training requirements would pose practical
problems for employers because of employee mobility and related
staffing concerns.
Based on the above-discussed concerns, the SIA made the following
recommendations regarding `additional' training requirements:
As a minimum, employers should be required to furnish to
employees working on scaffolds printed safety rules (Codes of Safe
Practice) for the particular type scaffold they are using. The
employee should be required to read the rules in the presence of the
employer or his agent (a competent person) and be questioned as to
whether the employee understands the rules.
Due to the extreme hazard associated with the use of suspended
scaffolds, a written training program should be required. The
program should include formal certification by the employer upon
completion of the program by the employee. Persons without such
training should not be allowed to work on suspended scaffolds.
OSHA notes that the training requirements in both the final rule
and the proposed rule have been framed in performance-oriented
language. This approach allows employers the flexibility to establish
programs which reconcile the need for training with the circumstances
at particular workplaces.
The AGC (Exs. 2-20, 2-55, and 2-390) contended that any additional
training requirements would be redundant and economically infeasible,
given the construction industry's high employee turnover. The GLFEA and
ABC (Exs. 2-22 and 2-69) commented that training requirements would
``impose practical problems'' due to workforce mobility. In addition,
the GLFEA, ABC and the Builders' Association of Missouri (Ex. 2-50)
stated that the requirements of Sec. 1926.21 already adequately address
training. The GLFEA added that ``other constraints * * * such as
insurance costs and workers compensation rates, impose a requirement on
* * * employers to train their employees and * * * follow safety
requirements.''
[[Page 46098]]
OSHA recognizes that employee turnover can increase an employer's
training responsibilities. The Agency notes, however, that the existing
standard already requires construction employers to provide training
for their employees, notwithstanding employee turnover or other day-to-
day changes in the employer's workforce. Furthermore, the Agency
believes that Sec. 1926.454, insofar as it elaborates on the training
requirements of existing Sec. 1926.21(b)(2), simply codifies good
industry practice and provides useful direction for how training
programs can ``do it right.'' Accordingly, OSHA has determined, based
on the rulemaking record, that any additional responsibilities imposed
by final rule Sec. 1926.454 are reasonable and necessary to protect
employees from serious hazards.
Furthermore, employers need not retrain employees who are trained
by a previous employer or were trained prior to the effective date of
the standard, as long as the employee demonstrates the proficiency
required by the pertinent provisions of this section. This approach is
consistent with that taken in part 1910, subpart I (Personal protective
equipment) and part 1926, subpart M (Fall protection).
A manufacturer of suspended scaffolds, Sky Climber, recommended
(Ex. 2-64) requiring that all riggers and operators of suspension
scaffold equipment be formally trained and certified and carry a
certificate or license to evidence their completion of training. That
commenter provided the following to explain their position:
Improper rigging and operator error were the second and third
major cause and cost of our product incidents. We believe that
training of operators and riggers will substantially reduce the
frequency and cost of incidents. In fact, of the over 1500 persons
who complete our Training Program in operation, maintenance and
rigging since 1980, to our knowledge, not one has been involved in a
suspension scaffold incident.
Sky Climber added that this training should be mandatory, and since
``[t]he primary responsibility for training rests with the employer * *
* he or some other qualified party should provide the required
training.''
Seedorff Masonry Inc.(Ex. 2-407) commented
We have always used our foreman as the instructor and this has
worked out very well. We can agree that there could be an additional
rule on this point, however additional paperwork would not be
feasible. We could find our superintendents only doing paperwork
without enough time to oversee job sites and develop good safety on
the job sites.
The SSFI (Ex. 2-367) commented in favor of proposed Sec. 1926.460,
stating as follows:
Members of the SSFI are in full support of the training
requirements for the contractor provided within the OSHA revision.
If followed, the training requirements would reduce the number of
accidents on construction projects. There currently exist many
Institute Safety Rules and Recommendations as well as many
recommendations developed by the manufacturers of the equipment. As
a minimum, those requirements can be used and, if followed, should
dramatically reduce the accidents of construction employees. These
construction employees should be trained by the contractor at the
construction site prior to their actual start of work, and should
not be trained on-the-job as they are working.
Alum-A-Pole Corporation, a manufacturer of pumpjack scaffolds,
stated (Ex. 2-31) ``[o]n-the-job training is the mode in which pumpjack
users gain proficiency in proper installation. On that basis,
sequential pictorial instructions with minimal verbiage * * * if
adhered to, would virtually eliminate accidents.''
Two commenters (Exs. 2-2 and 2-13) expressed the view that cost
should not be an issue in matters of safety. In addition, one of these
commenters (Ex. 2-13) found from his own experience that both employers
and employees should be trained and retrained.
Another commenter (Ex. 2-54) supported training and retraining and
provided details of the commenter's training program. The comment
touched on the value of discussions, involving both workers and
apprentices, regarding the proper way to use equipment. In particular,
the commenter indicated that employees are more productive when they
are confident that they have the right equipment and know how to use
it.
In addition, discussion by the ACCSH on Issue 15 noted that
training is cost-effective and beneficial for both employees and
employers (Tr. 6/9/87, pp. 130-136). One member stated: ``I've heard
several employers state that these training programs save 4 to 5
percent of the gross cost of the project, which oftentimes is more than
double the amount that they got the bid by in the first place.
They might have gotten the bid by less than 2 percent, but they
save 5 percent with the proper training program.''
Issue L-1 of the hearing notice (53 FR 2049) requested testimony
and related information on any current training programs which issue
certificates or licenses to indicate that employees have been
adequately trained to erect, use or dismantle specific types of
scaffolds. The Agency indicated that it was considering adding a
requirement for verification of compliance through a written
certification. In particular, OSHA sought comment on the following
language:
Sec. 1926.461 Certification. (a) The employer shall certify that
all employees who are erecting, maintaining and dismantling
scaffolds, have been adequately trained in the appropriate
precautions and safe practices before they are allowed to perform
any such scaffold work.
(b) The employer shall certify that the employee has been
trained by preparing a certification record which includes the
identity of the person trained, the signature of the employer or the
person who conducted the training, and the date the training or
retraining was completed. The certification record shall be prepared
at the completion of training and shall be maintained on file for
the duration of the employee's employment. The certification record
shall be made available upon request to the Assistant Secretary for
Occupational Safety and Health or designee.
Issue L-1 stated that the above language would not require the
``collection of information,'' and would not, therefore, impose a
paperwork burden on the employer under the terms of the Paperwork
Reduction Act (44 U.S.C. Chapter 35) and the implementing regulations
(5 CFR 1320.7(j)).
The Association of Wall and Ceiling Industries (AWCI) (Ex. 9; Tr.
3/22/88, p. 83-84) testified that certifying somebody as adequately
trained ``opens up a potential of increased liability so what I'm
asking OSHA to do for us is to provide some definition of `adequately
trained.' Whether this is a model training program or perhaps a listing
of the subjects to be covered under this adequacy of training and also
some indication of who's going to do the training.'' AWCI also asked
whether any employee who works on a scaffold must be trained in its
proper construction, placement, and care.
The AWCI (Ex. 9; Tr. 3/22/88, p. 84-85) also noted that, given the
constant exchange of employees in the construction industry,
``portability'' of training was a point of concern. They questioned,
for example, whether a contractor who has trained employees on a
project and rehires them a month and half later would have to retrain
them. Similarly, in response to a question regarding the type of
training scaffold erectors typically receive, AWCI stated that:
* * * most of it is on-the-job training that's handed down to
new employees as they come aboard the company or is brought by the
employees from the previous
[[Page 46099]]
company. The training programs could have been derived from the
manufacturer of the scaffolding equipment, could be derived from the
in-house training program that the contractor has and some of these
contractors have extensive programs in place on-site. It could also
be derived from the scaffold industry association * * * programs
that they have in place * * * '' (Ex. 9; Tr. 3/22/88, pp. 91-92.)
The AWCI further testified (Ex. 9; Tr. 3/22/88, p. 90) that EPA's
asbestos abatement certification program provided ``[t]he ground floor
of employee protection.'' They pointed out that the program requires 3
days of classroom training, including some ``hands-on,'' and includes a
listing of all points the program is to cover. In addition, the AWCI
testified that ``[the program] gives employees an added margin of
safety by making them aware of the hostile environment they're going to
be in, and added that a foreman, contractor, or supervisor must go for
an additional day of training and that they receive instruction
regarding insurance programs and legal ramifications.'' When asked to
comment on EPA's certification program versus that which might be
required for scaffold erection, the AWCI replied (Tr. 3/22/88, p. 91)
that OSHA should specify the points ``to be covered in the training
program and the credentials of the trainer'' if OSHA is going to
require a certification program.
In addition, Bristol Steel (Ex. 13; Tr. 3/23/88, pp. 2-147 and 2-
148) stated that certification is a weighty responsibility with
significant legal implications. Bristol Steel also contended that any
legal liability arising from a certification program should be the
burden of a trade organization (Tr. 3/23/88, pp. 2-181-182).
Bristol Steel also stated (Ex. 13) that the proposed certification
requirement would add a paperwork burden to employers. The commenter
added that before requiring certification, OSHA should show that such a
requirement could be ``implemented and universally enforced and will
cause a material reduction in scaffold accidents.''
The SIA testified (Ex. 10; Tr. 3/22/88 p. 151) that a certification
requirement would expose employers to ``tremendous liability to civil
and even criminal negligence suits in addition to those penalties
prescribed under OSHA.'' The SIA added that they ``worked closely with
Cal-OSHA in developing a certification program in 1981, which had to be
abandoned because the SIA and its members could not assume the
liability created by Cal-OSHA's insistence that we `certify the
competency of the worker'.''
The Montague-Betts Company, Inc. and SEAVAC testified that training
and certification of workers using scaffolds were appropriate and
useful, but that ``a lot of definition of scope and what certification
consists of is necessary before * * * people can take a final position
as to the complete merits and workings of such a proposal'' (Tr. 3/23/
88, pp. 2-198). Montague-Betts (Ex. 5a-5) stated that certification of
employees using scaffolds is appropriate. On the other hand, SEAVAC
(Ex. 5a-17) stated that certification is appropriate for employees who
erect or dismantle scaffolds but not for other employees.
The SSFI (Ex. 5a-19) stated that training for individuals who use
and erect scaffolds had been a subject of great debate within the
institute and stated that their members were ``very supportive of a
[s]tandard that would require training for the use, erection, and
dismantling of scaffolds.'' They recommended the following elements for
training:
--Two categories of training: one for scaffold users and one for
scaffold erectors and dismantlers;
--Issuing employee ``qualification cards'' that could be presented to
employers, and which would certify completion of a sanctioned training
program;
--Nationally uniform training programs;
--A national program requiring certification to balance economic
consideration among contractors;
--A gradual transition for the implementation of such a training
program;
--Permitting vocational trades, technical, or other qualified teaching
organizations or contractors to provide this type of training service;
--Not allowing training and certification to be substituted for
existing safety requirements, such as those provided by the equipment
manufacturer.
Some commenters opposed the certification language in Issue L-1.
One (Ex. 2-593) indicated that the training requirements in
Sec. 1926.21 and proposed Sec. 1926.460 were sufficient. Another (Ex.
2-594) called the section regarding certification ``too restrictive.''
Monsanto (Ex. 2-595) disagreed with certification of training and
retention of the certification in a file. Monsanto indicated that it
had not had problems with scaffold erection, maintenance, and
dismantling that would warrant certification of training. They added
that the proposed retention requirement for certification information
documents would ``present an unwarranted paperwork burden on the
employer.''
The Edison Electric Institute (Ex. 5a-6) responded that a written
certification was unnecessary and would add a significant paperwork
burden for employers. EEI added that regular training would assure that
employees know how to safely ``handle scaffolds.'' EEI also stated that
the work involved in these operations is not so sophisticated that
routine training should be considered inadequate.
OSHA has determined, based on its review of the record, that a
written certification would impose an additional burden on employers
without a demonstrable increase in worker safety. OSHA can determine if
workers have been adequately trained by talking with the employees and
observing their work habits. In addition, the Paperwork Reduction Act,
as recently revised, classifies certification as a type of information
burden for which OSHA must present a justification. Given the Agency's
conclusion that the necessary information can be obtained without
referring to documents, such a burden would not be justified.
Therefore, the final rule will not contain a requirement for training
certification.
Non-Mandatory Appendix A to Subpart L--Scaffold Specifications
This appendix is provided as a guide to assist employers in
complying with the requirements of Sec. 1926.451. This appendix is non-
mandatory. As stated above in the discussion of paragraph 1926.451(a),
scaffolds built in accordance with this Appendix A will be considered
to meet the intent of this revised subpart L. A full discussion of the
contents of this Appendix A, and any comments on the proposed Appendix
A, is found above, in the discussion of Sec. 1926.451(a).
Non-Mandatory Appendix B to Subpart L--Criteria for Determining the
Feasibility and Safety of Providing Safe Access and Fall Protection for
Scaffold Erectors and Dismantlers
This space is being reserved for publication of informational
guidance at a later date.
Non-Mandatory Appendix C to Subpart L--List of National Consensus
Standards
This Appendix is provided to serve as a guide to employers required
to provide appropriate employee protection under Sec. 1926.453, Aerial
Lifts. This Appendix reflects the proliferation of equipment-specific
ANSI A92 standards since the adoption of ANSI A92.2-1969.
[[Page 46100]]
Non-Mandatory Appendix D to Subpart L--List of Training Topics for
Scaffold Erectors and Dismantlers
OSHA has developed this Appendix to assist employers in identifying
appropriate topics for training scaffold erectors and dismantlers.
Non-Mandatory Appendix E to Subpart L--Drawings and Illustrations
This Appendix provides drawings of particular types of scaffolds
and scaffold components, and graphic illustrations of bracing patterns
and tie spacing patterns. It is intended to provide visual guidance to
assist the user in complying with the requirements of this standard.
IV. Economic Assessment and Regulatory Flexibility Analysis
Introduction
Executive Order (EO) 12866 requires regulatory agencies to conduct
an economic analysis for rules that meet certain criteria. The most
frequently used criterion under EO 12866 is that the rule will impose
annual costs on the economy of $100 million or more. OSHA's final
standard for scaffolds in construction does not meet this criterion, or
any of the other criteria specified by EO 12866, and therefore does not
require an economic analysis. Nevertheless, OSHA has decided to conduct
such an analysis to provide the regulated community with as much
information about the rule as possible. The Regulatory Flexibility Act
of 1980, as amended in 1996, requires OSHA to determine whether the
Agency's regulatory actions will have a significant impact on a
substantial number of small entities. Making this determination
requires OSHA to perform a screening analysis to identify any such
impacts. Consistent with these requirements, OSHA has prepared this
economic analysis and regulatory flexibility screening analysis of the
final rule for scaffolds in construction. The final rule being
published today will replace the outdated consensus standard addressing
scaffolds in construction that was adopted by OSHA in 1971 and has
remained largely unchanged since then.
This analysis includes a description of the industries affected by
the regulation, an evaluation of the risks addressed, an assessment of
the benefits attributable to the final standard, a determination of the
technological feasibility of the new requirements, an estimate of the
costs of compliance with the standard, a determination of the economic
feasibility of compliance with the standard, and an analysis of the
economic and other impacts associated with this rulemaking, including
those on small businesses. The following is a summary of this analysis,
which is available from OSHA's docket office.
The Final Standard for Scaffolds in Construction
This final standard for scaffolds in the construction industry
makes many changes to the consensus standard adopted by OSHA in 1971
and codified at 29 CFR 1926.450 to 1926.453 (Subpart L of OSHA's
construction industry standards). Appendix A of the Final Economic
Analysis compares, on a provision-by-provision basis, the final
standard with the standard that has been on the books since 1971. In
this economic analysis, the standard being published today is referred
to as the final standard, while the standard it replaces is termed the
``existing'' standard.
One of the important distinctions between the two standards is the
clarity and simplicity of the final standard, which is written in
language that people in the construction industry use to describe
scaffolds and their components. Technical terms required to convey
information accurately and unambiguously are defined clearly in
paragraph (b) of final rule Sec. 1926.450. The final rule also updates
the regulatory text to reflect changes in technology that have occurred
in the quarter century since the existing standard was written. These
changes will permit scaffold manufacturers and users to benefit from
technological change and give them additional flexibility in using up-
to-date equipment. The final standard also clarifies and resolves
issues of terminology or areas of confusion that have been identified
by scaffold users over the years. In the past, OSHA has addressed
implementation problems of this sort in letters of interpretation or
compliance memoranda or directives; the final standard corrects and
revises the provisions that gave rise to these interpretations.
Finally, the final standard adds protection for employees using
scaffolds. The principal areas in the new standard that have been
strengthened are employee training, protection from electrical hazards,
and procedures for employees engaged in the erection and dismantling of
scaffolds. These requirements reflect OSHA's long experience in
accident investigation in the construction industry, as well as an
extensive analysis of the leading causes of scaffold-related fatalities
and injuries.
Affected Industries
The requirements of the final standard apply to all establishments
in the construction industry. As classified by the 1987 Standard
Industrial Classification (SIC) manual, the industry can be divided
into three broad types of activities: building construction general
contractors (SIC 15), heavy construction general and special trade
contractors (SIC 16), and construction by other special trade
contractors (SIC 17).
There are 572,850 establishments in the construction sector
employing approximately 4.7 million employees. Small establishments
with one to nine employees, which represent 82 percent (or 469,349) of
establishments, collectively employ only 1.4 million employees (30
percent). The number of construction workers is estimated to be
approximately 3.6 million. OSHA estimates that there are approximately
2.34 million construction workers (65 percent of all construction
workers) who frequently work on scaffolds and who would be affected by
the final standard for scaffolds.
Evaluation of Risk and Potential Benefits
Of the 510,500 injuries and illnesses reportedly occurring in the
construction industry annually, an estimated 9,750 are related to
scaffolds. Similarly, of the estimated 924 occupational fatalities
occurring annually among construction employees, at least 79 fatalities
are associated with work on scaffolds. OSHA estimates that the new
requirements in the final rule will prevent 47 of these fatalities and
4,455 of these injuries annually; these numbers are above and beyond
the fatalities and injuries that would be prevented if construction
employers complied with OSHA's existing scaffold standard. OSHA
estimates that the total value of the cost savings associated with this
revised standard is $90 million per year. This estimate of cost savings
considers only those scaffold related injuries that involve lost
workdays.
Costs and Technological Feasibility
The total estimated costs associated with the final standard amount
to about $12.62 million annually. The largest single cost ($5.85
million) is associated with inspections of non-suspended scaffolds
before use. The remaining costs are attributable to requirements for
additional training for employees exposed to potential hazards
involving work on scaffolds ($5.30 million) and for fall protection for
employees erecting and dismantling scaffolds\1\ ($1.47 million). Table
ES-1 shows the annual costs of compliance associated with the final
rule.
[[Page 46101]]
Table ES-1.--Annual Costs of Compliance With the Final Rule for
Scaffolds in Construction
------------------------------------------------------------------------
Provision Annual cost
------------------------------------------------------------------------
Training: $5,298,708
Training for Workers Who Use Scaffolds.................. 3,014,949
Training for Scaffold Erectors, Dismantlers, Inspectors
and Repairers.......................................... 2,283,759
Fall Protection for Erectors and Dismantlers of
Scaffolds\1\............................................. 1,466,431
Scaffold Inspection....................................... 5,851,823
-------------
Total............................................... 12,616,962
------------------------------------------------------------------------
Source: US Department of Labor, OSHA, Office of Regulatory Analysis,
1996.
(1) This requirement has a one year delayed implementation date.
Because the requirements of the final standard can be met with
existing equipment and methods, the standard is technologically
feasible.
Economic Impacts
Compliance with the requirements of the final standard has been
determined to be economically feasible and is not expected to produce
significant adverse economic impacts on firms in the construction
industry. The estimated compliance costs represent less than 0.002
percent of construction revenues. Given the minimal price increase
necessary to cover the costs of the final standard, employers should be
able to pass these compliance costs on their customers. However, even
if all costs were absorbed by the affected firms (a highly unlikely
scenario), the average reduction in profits would be only 0.04 percent.
Regulatory Flexibility Screening Analysis
Pursuant to the Regulatory Flexibility Act of 1980 as amended (5
U.S.C. 601 et seq.), OSHA has assessed the small-business impact of the
final standard for scaffolds used in construction, and has certified
based on that assessment and the underlying data, that the standard
will not have a significant impact on a substantial number of small
entities. The controlling consideration for a regulatory flexibility
analysis is whether the standard would impose significant economic
impacts on a substantial number of small entities. The significance of
any economic impact is measured by the effect on profits, market share,
and an entity's financial viability.
The small establishment size standards established by the U.S.
Small Business Administration (SBA) for the construction industry,
which are based on establishment receipts, are $17 million for
establishments in SICs 15 and 16, and $7 million for establishments in
SIC 17. Of the 572,850 establishments affected by the revised standard,
493,637 1 establishments, or about 86 percent of all construction
establishments, are considered small establishments as defined by the
SBA.
---------------------------------------------------------------------------
\1\ 144,671 establishments in SIC 15, 28,206 establishments in
SIC 16 and 320,637 establishments in SIC 17.
---------------------------------------------------------------------------
OSHA assessed the potential economic impacts of the rule on all
affected establishments and has concluded that the rule is economically
feasible and will not impose a substantial burden on construction
employers. As indicated above, firms would only have to increase the
price charged for their services by, at most, 0.002 percent of the
value of their sales in order to recover the money they expended on
compliance. In the unlikely event that firms could not pass any of
these costs to their customers and had to absorb all of the costs
themselves (a highly unlikely scenario), the average reduction in
profits caused by these costs would be only 0.04 percent. On average,
the value of receipts for establishments in the construction industry
is estimated to be $1.12 million. Firms with sales in this range
clearly fall within the SBA size standard.
To ensure that even the smallest firms in this industry would not
be significantly impacted by the costs of compliance associated with
the final standard, OSHA also examined the financial profile for small
construction establishments with 9 or fewer employees at the four-digit
SIC code level, which constitutes the overwhelming majority of firms in
this industry. To examine the impact of the standard on the smallest
and potentially most affected firms, OSHA made a series of extreme-case
assumptions: that all employees in these establishments use scaffolds
in the course of their work and that these establishments have not
implemented any of the new work practices or procedures required by the
final rule. In addition, OSHA assumed that two employees at each firm
would require fall protection systems and training in the erection and
dismantling of supported-scaffolds. Assuming a baseline turnover rate
of 15 percent, and using the formulas presented in Chapter V of the
Economic Analysis, such a small establishment, which represents an
extreme-case impact situation, would incur compliance costs of $603
2 annually.
---------------------------------------------------------------------------
\2\ Annual 15 minute-training for workers who use scaffolds =
$11, annual training cost for erectors and dismantlers = $130,
annual cost of fall protection = $106, and annual scaffold
inspection cost = $356.
---------------------------------------------------------------------------
Table ES-2 presents the results of this extreme-case analysis. It
shows estimated compliance costs and economic impacts relative to
revenues and pre-tax income for small businesses by four-digit SIC code
level. OSHA compared the baseline financial data for these firms with
OSHA's estimate of the standard's annual compliance cost by computing
compliance costs as a percentage of revenue. This approach (Table ES-2)
reflects extreme case impacts because it assumes that employers have to
recover the costs of achieving compliance by increasing their prices.
Under this full cost pass-through scenario, the maximum average
expected price increase required to recover the full costs of
compliance with this standard would be extremely small, approximately
0.1 percent. The four-digit industry estimated to experience the
highest potential price increase would be Painting and Paper Hanging
(SIC 1721), where firms could have to increase prices by 0.18 percent.
Again, since these impacts are based on extreme-case costs, they are
likely to be overestimating.
Under the second scenario used to test the impacts of actions on
markets--the no cost pass-through scenario--firms are assumed not to be
able to pass any of their costs through to their customers in the form
of price increases. If no costs can be passed on, firms would have to
absorb these costs entirely from their profits (a highly unlikely
scenario). Using this assumption, the average expected decline in
profits for these very small firms would be only 1.44 percent. The
largest potential impact of the standard would be anticipated in the
Plastering, Drywall and Acoustical industry (SIC 1742), where firms
could experience a decline in profits of 2.71 percent. Such impacts are
not large enough to be significant because they mean, for example, that
the profit rate for such a company would decline only from 5.0 percent
to 4.9 3 percent. As noted, these figures are based on highly
conservative assumptions and are therefore likely to overestimate
standard's impact.
---------------------------------------------------------------------------
\3\ $22,265/$445,303 = 5.0%, $22,265 x (100 - 2.71%) /$445,303
= 4.9%.
---------------------------------------------------------------------------
Because fixed costs, such as those for preparing training
materials, are larger as a percentage of revenues the smaller the firm,
the smallest firms will experience the greatest economic
[[Page 46102]]
impacts. If the smallest firms, with extreme-case costs, will
experience no significant impact, it is reasonable to conclude that
larger firms will not experience significant economic impacts. Thus,
because this standard will not have a significant impact either on the
smallest establishments (those with 9 or fewer employees) or on the
typical establishment in this industry, OSHA certifies that this final
standard will not have a significant economic impact on a substantial
number of small entities, as defined by the SBA.
Table ES-2.--Economic Impacts of the Final Scaffold Standard on Construction Businesses With 5 Employees. By 4-
Digit SIC, Using Worst-Case Compliance Assumptions
----------------------------------------------------------------------------------------------------------------
Value of Compliance
industry Pre-tax Compliance costs as a
SIC industry receipts per income per costs as a percent of
establishment establishment percent of pre-tax
[a] [b] revenues income
----------------------------------------------------------------------------------------------------------------
15 Building Construction-General Contractors......... $1,039,353 $56,692 0.06 1.06
1521 General Contractors-Single-Family Houses.......... 824,664 61,225 .07 0.98
1522 General Contractors-Residential Buildings......... 989,058 73,430 .06 0.82
1531 Operative Builders................................ 2,459,972 81,999 .02 0.73
1541 General Contractors-Industrial Buildings &
Warehouses............................................. 1,159,689 52,713 .05 1.14
1542 General Contractors-Non-residential Buildings..... 1,278,174 61,972 .05 0.97
16 Heavy Construction Other than Building
Construction........................................... 934,365 59,460 .06 1.01
1622 Bridge, Tunnel and Elevated Highway Construction.. 1,312,204 47,717 .05 1.26
1623 Water, Sewer, Pipeline and Communications......... 832,093 50,430 .07 1.19
1629 Heavy Construction, nec........................... 717,664 50,019 .08 1.20
17 Special Trade Contractors......................... 471,876 32,888 .13 1.83
1711 Plumbing, Heating & Air Conditioning.............. 520,496 31,545 .12 1.91
1721 Painting and Paper Hanging........................ 331,775 30,664 .18 1.96
1731 Electrical Work................................... 463,498 34,411 .13 1.75
1741 Masonry, Stone Setting............................ 357,551 25,462 .17 2.37
1742 Plastering, Drywall, Acoustical................... 445,303 22,265 .14 2.71
1743 Terrazzo, Tile, Marble and Mosaic Work............ 404,702 28,820 .15 2.09
1751 Carpentry Work.................................... 414,681 32,672 .15 1.84
1752 Floor Laying and Other Floor Work, nec............ 573,175 39,949 .11 1.51
1761 Roofing, Siding and Sheet Metal Work.............. 470,902 30,680 .13 1.96
1771 Concrete Work..................................... 510,955 36,386 .12 1.66
1791 Structural Steel Erection......................... 541,947 36,130 .11 1.67
1793 Glass and Glazing Work............................ 555,960 32,852 .11 1.83
1796 Installation or Erection of Building Equipment,
nec.................................................... 581,564 30,841 .10 1.95
1799 Special Trade Contractors, nec.................... 504,453 40,509 .12 1.49
-------------------------------------------------------
Average............................................. ............. ............. .10 1.44
----------------------------------------------------------------------------------------------------------------
Source: U.S. Department of Labor, OSHA, Office of Regulatory Analysis, 1996.
[a] Based on Small Business Administration, Office of Advocacy, Table 3: The Number of Firms, Establishments,
Employment, Annual Payroll, and Estimated Receipts by Industry and Firm Size, 1993.
[b] Average revenue per establishment x mean profit rate for SIC (derived from Dun and Bradstreet Information
Services, Industry Norms and Key Business Ratios 1994-95) x conversion formula based on the federal corporate
tax schedule.
[c] Annual cost of compliance of 603 per establishment assumes that all workers (5) would require training in
the initial year and that all new workers in subsequent years would require training. Two workers will be
trained in dismantling and erecting procedures. Estimates also assume that fall protection will be required
for erectors and dismantlers and that inspections of non-suspended scaffolds will be required.
nec=Not elsewhere classified.
In addition, OSHA has drafted the final standard for scaffolds in
the construction industry to achieve adequate protection for affected
employees while imposing minimal impacts on small employers. For
example, the final rule maintains the performance-oriented approach of
the proposed standard, allowing employers the flexibility to take
workplace conditions into account when framing their compliance
strategies. In addition, OSHA considered and adopted several
alternatives designed to minimize small business impacts. For example,
revisions reflected in the final standard's requirements for fall
protection (grandfathering existing guardrail systems and allowing some
use of crossbracing in lieu of guardrails) will enable small entities
to minimize their compliance burdens. Accordingly, OSHA has determined
that the final rule effectively addresses small employer concerns.
V. Environmental Assessment
Finding of No Significant Impact
This final rule and its major alternatives have been reviewed in
accordance with the requirements of the National Environmental Policy
Act (NEPA) of 1969 (42 U.S.C. 4321 et seq.), the Guidelines of the
Council on Environmental Quality (CEQ) (40 CFR part 1500), and OSHA's
DOL NEPA Procedures (29 CFR part 11). As a result of this review, the
Assistant Secretary for OSHA has determined that the final rule will
have no significant environmental impact.
The revisions to Subpart L--Scaffolds focus on the reduction of
accidents or injuries by means of work practices and procedures, proper
use and handling of equipment, and training, as well as on changes in
language, definition, and format of the standard. These revisions do
not impact on air, water, or soil quality, plant or animal life, the
use of land, or other aspect of the environment. As such, these
revisions are, therefore, categorized as excluded actions according to
subpart B, Sec. 11.10, of the DOL NEPA regulation.
VI. Pertinent Legal Authority
The purpose of the Occupational Safety and Health Act, 29 U.S.C.
Secs. 651
[[Page 46103]]
et seq. (``the Act''), is ``to assure so far as possible every working
man and woman in the Nation safe and healthful working conditions and
to preserve our human resources.'' 29 U.S.C. Sec. 651(b). To achieve
this goal, Congress authorized the Secretary of Labor to promulgate and
enforce occupational safety and health standards. 29 U.S.C.
Secs. 655(a) (authorizing summary adoption of existing consensus and
federal standards within two years of Act's enactment), 655(b)
(authorizing promulgation of standards pursuant to notice and comment),
654(b) (requiring employers to comply with OSHA standards).
A safety or health standard is a standard ``which requires
conditions, or the adoption or use of one or more practices, means,
methods, operations, or processes, reasonably necessary or appropriate
to provide safe or healthful employment.'' 29 U.S.C. Sec. 652(8).
A standard is reasonably necessary or appropriate within the
meaning of Section 652(8) if it substantially reduces or eliminates
significant risk, and is economically feasible, technologically
feasible, cost effective, consistent with prior Agency action or a
justified departure, supported by substantial evidence, and is better
able to effectuate the Act's purposes than any national consensus
standard it supersedes. See 58 Fed. Reg. 16612-16616 (March 30, 1993).
OSHA has generally considered, at minimum, a fatality risk of 1/
1000 over a 45-year working lifetime to be a significant health risk.
See the Benzene standard, Industrial Union Dep't v. American Petroleum
Institute, 448 U.S. 607, 646 (1980); the Asbestos standard, Building
and Constr. Trades Dep't, AFL-CIO v. Brock, 838 F.2d 1258, 1265 (D.C.
Cir 1988); the Formaldehyde standard, International Union, UAW v.
Pendergrass, 878 F.2d 389, 392 (D.C. Cir 1989).
A standard is technologically feasible if the protective measures
it requires already exist, can be brought into existence with available
technology, or can be created with technology that can reasonably be
expected to be developed. American Textile Mfrs. Institute v. OSHA, 452
U.S. 490, 513 (1981) (``ATMI''); AISI v. OSHA, 939 F.2d 975, 980 (D.C.
Cir. 1991).
A standard is economically feasible if industry can absorb or pass
on the costs of compliance without threatening its long term
profitability or competitive structure. See ATMI, 452 U.S. at 530 n.
55; AISI, 939 F.2d at 980.
A standard is cost effective if the protective measures it requires
are the least costly of the available alternatives that achieve the
same level of protection. ATMI, 453 U.S. at 514 n. 32; International
Union, UAW v. OSHA, 37 F.3d 665, 668 (D.C. Cir. 1994) (``LOTO III'').
Section 6(b)(7) authorizes OSHA to include among a standard's
requirements labeling, monitoring, medical testing and other
information gathering and transmittal provisions. 29 U.S.C.
Sec. 655(b)(7).
All standards must be highly protective. See 58 Fed. Reg. at 16614-
16615; LOTO III, 37 F.3d at 669. Finally, whenever practical, standards
shall ``be expressed in terms of objective criteria and of the
performance desired.'' Id.
VII. Recordkeeping
The Agency has estimated the paperwork burden of the final rule
entitled ``Scaffolds Used in the Construction Industry'' under the
guidelines of the Paperwork Reduction Act of 1995. Under that Act,
burden is defined as the total time, effort, or financial resources
expended by persons to generate, maintain, retain, or disclose or
provide information to or for a Federal Agency. The Agency has
concluded that there is only one collection of information in the final
rule on ``Scaffolds Used in the Construction Industry'' that
potentially could create a burden [as defined above] for the
construction industry. The collection of information in located in
Sec. 1926.453(a)(2). This provision requires the employer to obtain a
written certification from the manufacture of aerial lifts under
certain specified conditions. In particular, the requirement reads as
follows:
Aerial lifts may be ``field modified'' for uses other than those
intended by the manufacturer provided the modification has been
certified in writing by the manufacturer or by any other equivalent
entity, such as a nationally recognized testing laboratory, to be in
conformity with all the applicable provisions of the ANSI A92.2-1969
and this section and to be at least as safe as the equipment was
before modification.
This provision was adopted by OSHA in May 1971 as an established
Federal standard which had been promulgated by the Bureau of Labor
Standards for the Construction Industry in April 1971. OSHA failed to
identify this provision as subject to the Paperwork Reduction Act of
1995 (PRA-95) and did not obtain approval from OMB for this collection
as required by PRA-95. This error was discovered in the course of
preparing the final rule for Scaffolds Used in the Construction
Industry. This provision, currently located in Sec. 1926.556(a)(2) is
redesignated as Sec. 1926.453(a)(2) and removed unchanged from its
present location in Subpart N to Subpart L (Scaffolds Used in the
Construction Industry). Through this final rule, OSHA is soliciting
comments on the burden associated with the collection. It is OSHA
intent to review and analyze all comments received on the collection of
information and then to seek proper approvals from OMB under PRA-95.
Once approval is received, OSHA will publish a notice in the Federal
Register to indicate the OMB Approval Number and the effective date of
the provision.
Collections of Information: Request for Comments
The Department of Labor, as part of its continuing effort to reduce
paperwork and respondent burden, conducts a preclearance consultation
program to provide the general public and Federal agencies with an
opportunity to comment on proposed and/or continuing collections of
information in accordance with the Paperwork Reduction Act of 1995
(PRA95) (44 U.S.C. 3506(c)(2)(A)). This program helps to ensure that
requested data can be provided in the desired format, reporting burden
(time and financial resources) is minimized, collection instruments are
clearly understood, and the impact of collection requirements on the
respondents can be properly assessed. Currently, OSHA is soliciting
comments concerning the proposed approval for the paperwork
requirements of 29 CFR part 1926, subpart L, Scaffolds used in the
Construction Industry. Written comments should:
Evaluate whether the proposed collection of information is
necessary for the proper performance of the function of the agency,
including whether the information will have a practical utility;
Evaluate the accuracy of the Agency's estimate of the
burden of the proposed collection of information, including the
validity of the methodology and assumptions used;
Enhance the quality, utility, and clarity of the
information to be collected; and
Minimize the burden of the collection of information on
those who are to respond, including through the use of appropriate
automated, electronic, mechanical, or other technological collection
techniques or other forms of information technology, e.g., permitting
electronic submissions of responses.
Background
OSHA in its final rule for Scaffolds Used in the Construction
Industry is
[[Page 46104]]
redesignating existing Sec. 1926.556 (subpart N), Aerial Lifts to
Sec. 1926.453 (subpart L), Aerial Lifts because these type of equipment
are, in fact, scaffolds. The existing regulation, Sec. 1926.556(a)(2),
contained a requirement for manufacturer certification of ``field
modified'' aerial lifts. This provision, along with the rest of
Sec. 1296.556, is being redesignated Sec. 1926.453(a)(2) in this final
rule.
OSHA believes that manufacturer certification of ``field modified''
aerial lifts is necessary to ensure that modifications to these types
of scaffolds will not adversely affect the strength, stability, or
other characteristics necessary for their safe use.
Current Actions
This notice requests OMB approval of the paperwork requirements in
Scaffolds Used in the Construction Industry (29 CFR 1926, subpart L).
Type of Review: New.
Agency: Occupational Safety and Health Administration, U.S.
Department of Labor.
Title: Scaffolds Used in the Construction Industry (29 CFR 1926,
subpart L).
OMB Number: 1218-AA40.
Agency Docket No.: S-205.
Frequency: On occasion.
Affected Public: Business or other for-profit, Federal government,
State and local governments.
Number of respondents: 10,000.
Estimated Time per Respondent: 2 hours.
Total Estimated Cost: $513,200.
Total Burden Hours: 20,000.
Comments submitted in response to this notice will be summarized
and/or included in the request for Office of Management and Budget
approval of the information collection request. They will also become a
matter of public record.
VIII. State Plan Standards
The 25 states and territories with their own OSHA-approved
occupational safety and health plans must adopt a comparable standard
within 6 months of the publication date of the final rule. These states
and territories are: Alaska, Arizona, California, Connecticut (for
State and local government employees only), Hawaii, Indiana, Iowa,
Kentucky, Maryland, Michigan, Minnesota, New York (for State and local
government employees only), Nevada, New Mexico, North Carolina, Oregon,
Puerto Rico, South Carolina, Tennessee, Utah, Vermont, Virginia, Virgin
Islands, Washington, and Wyoming. Until such time as a comparable
standard is promulgated, Federal OSHA will provide interim enforcement
assistance, as appropriate, in these states and territories.
IX. Federalism
The final rule has been reviewed in accordance with Executive Order
12612 (52 FR 41685, October 30, 1987) regarding Federalism. The Order
requires that agencies, to the extent possible, refrain from limiting
State policy options, consult with states prior to taking any actions
that would restrict State policy options, and take such actions only
when there is clear constitutional authority and the presence of a
problem of national scope. The Order provides for preemption of State
law only if there is a clear Congressional intent for the agency to do
so. Any such preemption is to be limited to the extent possible.
Section 18 of the Occupational Safety and Health Act (OSH Act),
expresses Congress' clear intent to preempt State laws relating to
issues with respect to which Federal OSHA has promulgated occupational
safety and health standards. Under the OSH Act, a State can avoid
preemption only if it submits, and obtains Federal approval of a plan
for the development of such standards and their enforcement.
Occupational safety and health standards developed by such Plan States
must, among other things, be at least as effective in providing safe
and healthful employment and places of employment as the Federal
standards. Where such standards are applicable to products distributed
or used in interstate commerce, they may not unduly burden commerce and
must be justified by compelling local conditions, see section 18(c)(2).
The Federal standard on construction operations involving scaffolds
addresses hazards that are not unique to any one state or region of the
country. Nonetheless, States with occupational safety and health plans
approved under section 18 of the OSH Act will be able to develop their
own State standards to deal with any special problems which might be
encountered in a particular State. Moreover, because this standard is
written in general, performance-oriented terms, there is considerable
flexibility to State plans to require, and for affected employers to
use, methods of compliance which are appropriate to the working
conditions covered by the standard.
In brief, this final rule addresses a clear national problem
related to occupational safety and health in the construction industry.
Those states which have elected to participate under section 18 of the
OSH Act are not preempted by this standard, and will be able to address
any special conditions within the framework of the Federal Act while
ensuring that the state standards are at least as effective as that
standard.
List of Subjects in 29 CFR Part 1926
Construction industry, Construction safety, Occupational safety and
health, Protective equipment, Safety, Scaffolds.
Authority
This document was prepared under the direction of Joseph A. Dear,
Assistant Secretary of Labor for Occupational Safety and Health, U.S.
Department of Labor, 200 Constitution Avenue, N.W., Washington, D.C.
20210.
Accordingly, pursuant to sections 4, 6, and 8 of the Occupational
Safety and Health Act of 1970 (29 U.S.C. 653, 655, 657), section 107 of
the Contract Work Hours and Safety Standards Act (40 U.S.C. 333),
Secretary of Labor's Order No. 1-90 (55 FR 9033), and 29 CFR part 1911,
29 CFR part 1926 is amended as set forth below.
Signed at Washington, D.C., this 16th day of August 1996.
Joseph A. Dear,
Assistant Secretary of Labor.
PART 1926--[AMENDED]
1. Subpart L of Part 1926 is revised to read as follows:
Subpart L--Scaffolds
Sec.
1926.450 Scope, application and definitions applicable to this
subpart.
1926.451 General requirements.
1926.452 Additional requirements applicable to specific types of
scaffolds.
1926.453 Aerial lifts.
1926.454 Training.
Appendix A to Subpart L--Scaffolds
Appendix B to Subpart L--Scaffolds
Appendix C to Subpart L--Scaffolds
Appendix D to Subpart L--Scaffolds
Appendix E to Subpart L--Scaffolds
Authority: Section 107, Contract Work Hours and Safety Standards
Act (Construction Safety Act) (40 U.S.C. 333); Secs. 4, 6, 8,
Occupational Safety and Health Act of 1970 (29 U.S.C. 653, 655,
657); Secretary of Labor's Order No. 1-90 (55 FR 9033); and 29 CFR
Part 1911.
Subpart L--Scaffolds
Sec. 1926.450 Scope, application and definitions applicable to this
subpart.
(a) Scope and application. This subpart applies to all scaffolds
used in workplaces covered by this part. It does not apply to crane or
derrick suspended personnel platforms, which are covered by
Sec. 1926.550(g). The criteria for aerial lifts are set out exclusively
in Sec. 1926.453.
[[Page 46105]]
(b) Definitions. Adjustable suspension scaffold means a suspension
scaffold equipped with a hoist(s) that can be operated by an
employee(s) on the scaffold.
Bearer (putlog) means a horizontal transverse scaffold member
(which may be supported by ledgers or runners) upon which the scaffold
platform rests and which joins scaffold uprights, posts, poles, and
similar members.
Boatswains' chair means a single-point adjustable suspension
scaffold consisting of a seat or sling designed to support one employee
in a sitting position.
Body belt (safety belt) means a strap with means both for securing
it about the waist and for attaching it to a lanyard, lifeline, or
deceleration device.
Body harness means a design of straps which may be secured about
the employee in a manner to distribute the fall arrest forces over at
least the thighs, pelvis, waist, chest and shoulders, with means for
attaching it to other components of a personal fall arrest system.
Brace means a rigid connection that holds one scaffold member in a
fixed position with respect to another member, or to a building or
structure.
Bricklayers' square scaffold means a supported scaffold composed of
framed squares which support a platform.
Carpenters' bracket scaffold means a supported scaffold consisting
of a platform supported by brackets attached to building or structural
walls.
Catenary scaffold means a suspension scaffold consisting of a
platform supported by two essentially horizontal and parallel ropes
attached to structural members of a building or other structure.
Additional support may be provided by vertical pickups.
Chimney hoist means a multi-point adjustable suspension scaffold
used to provide access to work inside chimneys. (See ``Multi-point
adjustable suspension scaffold''.)
Cleat means a structural block used at the end of a platform to
prevent the platform from slipping off its supports. Cleats are also
used to provide footing on sloped surfaces such as crawling boards.
Competent person means one who is capable of identifying existing
and predictable hazards in the surroundings or working conditions which
are unsanitary, hazardous, or dangerous to employees, and who has
authorization to take prompt corrective measures to eliminate them.
Continuous run scaffold (Run scaffold) means a two- point or multi-
point adjustable suspension scaffold constructed using a series of
interconnected braced scaffold members or supporting structures erected
to form a continuous scaffold.
Coupler means a device for locking together the tubes of a tube and
coupler scaffold.
Crawling board (chicken ladder) means a supported scaffold
consisting of a plank with cleats spaced and secured to provide
footing, for use on sloped surfaces such as roofs.
Deceleration device means any mechanism, such as a rope grab, rip-
stitch lanyard, specially-woven lanyard, tearing or deforming lanyard,
or automatic self-retracting lifeline lanyard, which dissipates a
substantial amount of energy during a fall arrest or limits the energy
imposed on an employee during fall arrest.
Double pole (independent pole) scaffold means a supported scaffold
consisting of a platform(s) resting on cross beams (bearers) supported
by ledgers and a double row of uprights independent of support (except
ties, guys, braces) from any structure.
Equivalent means alternative designs, materials or methods to
protect against a hazard which the employer can demonstrate will
provide an equal or greater degree of safety for employees than the
methods, materials or designs specified in the standard.
Exposed power lines means electrical power lines which are
accessible to employees and which are not shielded from contact. Such
lines do not include extension cords or power tool cords.
Eye or Eye splice means a loop with or without a thimble at the end
of a wire rope.
Fabricated decking and planking means manufactured platforms made
of wood (including laminated wood, and solid sawn wood planks), metal
or other materials.
Fabricated frame scaffold (tubular welded frame scaffold) means a
scaffold consisting of a platform(s) supported on fabricated end frames
with integral posts, horizontal bearers, and intermediate members.
Failure means load refusal, breakage, or separation of component
parts. Load refusal is the point where the ultimate strength is
exceeded.
Float (ship) scaffold means a suspension scaffold consisting of a
braced platform resting on two parallel bearers and hung from overhead
supports by ropes of fixed length.
Form scaffold means a supported scaffold consisting of a platform
supported by brackets attached to formwork.
Guardrail system means a vertical barrier, consisting of, but not
limited to, toprails, midrails, and posts, erected to prevent employees
from falling off a scaffold platform or walkway to lower levels.
Hoist means a manual or power-operated mechanical device to raise
or lower a suspended scaffold.
Horse scaffold means a supported scaffold consisting of a platform
supported by construction horses (saw horses). Horse scaffolds
constructed of metal are sometimes known as trestle scaffolds.
Independent pole scaffold (see ``Double pole scaffold'').
Interior hung scaffold means a suspension scaffold consisting of a
platform suspended from the ceiling or roof structure by fixed length
supports.
Ladder jack scaffold means a supported scaffold consisting of a
platform resting on brackets attached to ladders.
Ladder stand means a mobile, fixed-size, self-supporting ladder
consisting of a wide flat tread ladder in the form of stairs.
Landing means a platform at the end of a flight of stairs.
Large area scaffold means a pole scaffold, tube and coupler
scaffold, systems scaffold, or fabricated frame scaffold erected over
substantially the entire work area. For example: a scaffold erected
over the entire floor area of a room.
Lean-to scaffold means a supported scaffold which is kept erect by
tilting it toward and resting it against a building or structure.
Lifeline means a component consisting of a flexible line that
connects to an anchorage at one end to hang vertically (vertical
lifeline), or that connects to anchorages at both ends to stretch
horizontally (horizontal lifeline), and which serves as a means for
connecting other components of a personal fall arrest system to the
anchorage.
Lower levels means areas below the level where the employee is
located and to which an employee can fall. Such areas include, but are
not limited to, ground levels, floors, roofs, ramps, runways,
excavations, pits, tanks, materials, water, and equipment.
Masons' adjustable supported scaffold (see ``Self-contained
adjustable scaffold'').
Masons' multi-point adjustable suspension scaffold means a
continuous run suspension scaffold designed and used for masonry
operations.
Maximum intended load means the total load of all persons,
equipment, tools, materials, transmitted loads, and other loads
reasonably anticipated to be applied to a scaffold or scaffold
component at any one time.
[[Page 46106]]
Mobile scaffold means a powered or unpowered, portable, caster or
wheel-mounted supported scaffold.
Multi-level suspended scaffold means a two-point or multi-point
adjustable suspension scaffold with a series of platforms at various
levels resting on common stirrups.
Multi-point adjustable suspension scaffold means a suspension
scaffold consisting of a platform(s) which is suspended by more than
two ropes from overhead supports and equipped with means to raise and
lower the platform to desired work levels. Such scaffolds include
chimney hoists.
Needle beam scaffold means a platform suspended from needle beams.
Open sides and ends means the edges of a platform that are more
than 14 inches (36 cm) away horizontally from a sturdy, continuous,
vertical surface (such as a building wall) or a sturdy, continuous
horizontal surface (such as a floor), or a point of access. Exception:
For plastering and lathing operations the horizontal threshold distance
is 18 inches (46 cm).
Outrigger means the structural member of a supported scaffold used
to increase the base width of a scaffold in order to provide support
for and increased stability of the scaffold.
Outrigger beam (Thrustout) means the structural member of a
suspension scaffold or outrigger scaffold which provides support for
the scaffold by extending the scaffold point of attachment to a point
out and away from the structure or building.
Outrigger scaffold means a supported scaffold consisting of a
platform resting on outrigger beams (thrustouts) projecting beyond the
wall or face of the building or structure, the inboard ends of which
are secured inside the building or structure.
Overhand bricklaying means the process of laying bricks and masonry
units such that the surface of the wall to be jointed is on the
opposite side of the wall from the mason, requiring the mason to lean
over the wall to complete the work. It includes mason tending and
electrical installation incorporated into the brick wall during the
overhand bricklaying process.
Personal fall arrest system means a system used to arrest an
employee's fall. It consists of an anchorage, connectors, a body belt
or body harness and may include a lanyard, deceleration device,
lifeline, or combinations of these.
Platform means a work surface elevated above lower levels.
Platforms can be constructed using individual wood planks, fabricated
planks, fabricated decks, and fabricated platforms.
Pole scaffold (see definitions for ``Single-pole scaffold'' and
``Double (independent) pole scaffold'').
Power operated hoist means a hoist which is powered by other than
human energy.
Pump jack scaffold means a supported scaffold consisting of a
platform supported by vertical poles and movable support brackets.
Qualified means one who, by possession of a recognized degree,
certificate, or professional standing, or who by extensive knowledge,
training, and experience, has successfully demonstrated his/her ability
to solve or resolve problems related to the subject matter, the work,
or the project.
Rated load means the manufacturer's specified maximum load to be
lifted by a hoist or to be applied to a scaffold or scaffold component.
Repair bracket scaffold means a supported scaffold consisting of a
platform supported by brackets which are secured in place around the
circumference or perimeter of a chimney, stack, tank or other
supporting structure by one or more wire ropes placed around the
supporting structure.
Roof bracket scaffold means a rooftop supported scaffold consisting
of a platform resting on angular-shaped supports.
Runner (ledger or ribbon) means the lengthwise horizontal spacing
or bracing member which may support the bearers.
Scaffold means any temporary elevated platform (supported or
suspended) and its supporting structure (including points of
anchorage), used for supporting employees or materials or both.
Self-contained adjustable scaffold means a combination supported
and suspension scaffold consisting of an adjustable platform(s) mounted
on an independent supporting frame(s) not a part of the object being
worked on, and which is equipped with a means to permit the raising and
lowering of the platform(s). Such systems include rolling roof rigs,
rolling outrigger systems, and some masons' adjustable supported
scaffolds.
Shore scaffold means a supported scaffold which is placed against a
building or structure and held in place with props.
Single-point adjustable suspension scaffold means a suspension
scaffold consisting of a platform suspended by one rope from an
overhead support and equipped with means to permit the movement of the
platform to desired work levels.
Single-pole scaffold means a supported scaffold consisting of a
platform(s) resting on bearers, the outside ends of which are supported
on runners secured to a single row of posts or uprights, and the inner
ends of which are supported on or in a structure or building wall.
Stair tower (Scaffold stairway/tower) means a tower comprised of
scaffold components and which contains internal stairway units and rest
platforms. These towers are used to provide access to scaffold
platforms and other elevated points such as floors and roofs.
Stall load means the load at which the prime-mover of a power-
operated hoist stalls or the power to the prime-mover is automatically
disconnected.
Step, platform, and trestle ladder scaffold means a platform
resting directly on the rungs of step ladders or trestle ladders.
Stilts means a pair of poles or similar supports with raised
footrests, used to permit walking above the ground or working surface.
Stonesetters' multi-point adjustable suspension scaffold means a
continuous run suspension scaffold designed and used for stonesetters'
operations.
Supported scaffold means one or more platforms supported by
outrigger beams, brackets, poles, legs, uprights, posts, frames, or
similar rigid support.
Suspension scaffold means one or more platforms suspended by ropes
or other non-rigid means from an overhead structure(s).
System scaffold means a scaffold consisting of posts with fixed
connection points that accept runners, bearers, and diagonals that can
be interconnected at predetermined levels.
Tank builders' scaffold means a supported scaffold consisting of a
platform resting on brackets that are either directly attached to a
cylindrical tank or attached to devices that are attached to such a
tank.
Top plate bracket scaffold means a scaffold supported by brackets
that hook over or are attached to the top of a wall. This type of
scaffold is similar to carpenters' bracket scaffolds and form scaffolds
and is used in residential construction for setting trusses.
Tube and coupler scaffold means a supported or suspended scaffold
consisting of a platform(s) supported by tubing, erected with coupling
devices connecting uprights, braces, bearers, and runners.
Tubular welded frame scaffold (see ``Fabricated frame scaffold'').
Two-point suspension scaffold (swing stage) means a suspension
scaffold consisting of a platform supported by hangers (stirrups)
suspended by two ropes from overhead supports and equipped with means
to permit the
[[Page 46107]]
raising and lowering of the platform to desired work levels.
Unstable objects means items whose strength, configuration, or lack
of stability may allow them to become dislocated and shift and
therefore may not properly support the loads imposed on them. Unstable
objects do not constitute a safe base support for scaffolds, platforms,
or employees. Examples include, but are not limited to, barrels, boxes,
loose brick, and concrete blocks.
Vertical pickup means a rope used to support the horizontal rope in
catenary scaffolds.
Walkway means a portion of a scaffold platform used only for access
and not as a work level.
Window jack scaffold means a platform resting on a bracket or jack
which projects through a window opening.
Sec. 1926.451 General requirements.
This section does not apply to aerial lifts, the criteria for which
are set out exclusively in Sec. 1926.453.
(a) Capacity (1) Except as provided in paragraphs (a)(2), (a)(3),
(a)(4), (a)(5) and (g) of this section, each scaffold and scaffold
component shall be capable of supporting, without failure, its own
weight and at least 4 times the maximum intended load applied or
transmitted to it.
(2) Direct connections to roofs and floors, and counterweights used
to balance adjustable suspension scaffolds, shall be capable of
resisting at least 4 times the tipping moment imposed by the scaffold
operating at either the rated load of the hoist, or 1.5 (minimum) times
the tipping moment imposed by the scaffold operating at the stall load
of the hoist, whichever is greater.
(3) Each suspension rope, including connecting hardware, used on
non-adjustable suspension scaffolds shall be capable of supporting,
without failure, at least 6 times the maximum intended load applied or
transmitted to that rope.
(4) Each suspension rope, including connecting hardware, used on
adjustable suspension scaffolds shall be capable of supporting, without
failure, at least 6 times the maximum intended load applied or
transmitted to that rope with the scaffold operating at either the
rated load of the hoist, or 2 (minimum) times the stall load of the
hoist, whichever is greater.
(5) The stall load of any scaffold hoist shall not exceed 3 times
its rated load.
(6) Scaffolds shall be designed by a qualified person and shall be
constructed and loaded in accordance with that design. Non-mandatory
Appendix A to this subpart contains examples of criteria that will
enable an employer to comply with paragraph (a) of this section.
(b) Scaffold platform construction. (1) Each platform on all
working levels of scaffolds shall be fully planked or decked between
the front uprights and the guardrail supports as follows:
(i) Each platform unit (e.g., scaffold plank, fabricated plank,
fabricated deck, or fabricated platform) shall be installed so that the
space between adjacent units and the space between the platform and the
uprights is no more than 1 inch (2.5 cm) wide, except where the
employer can demonstrate that a wider space is necessary (for example,
to fit around uprights when side brackets are used to extend the width
of the platform).
(ii) Where the employer makes the demonstration provided for in
paragraph (b)(1)(i) of this section, the platform shall be planked or
decked as fully as possible and the remaining open space between the
platform and the uprights shall not exceed 9\1/2\ inches (24.1 cm).
Exception to paragraph (b)(1): The requirement in paragraph (b)(1)
to provide full planking or decking does not apply to platforms used
solely as walkways or solely by employees performing scaffold erection
or dismantling. In these situations, only the planking that the
employer establishes is necessary to provide safe working conditions is
required.
(2) Except as provided in paragraphs (b)(2)(i) and (b)(2)(ii) of
this section, each scaffold platform and walkway shall be at least 18
inches (46 cm) wide.
(i) Each ladder jack scaffold, top plate bracket scaffold, roof
bracket scaffold, and pump jack scaffold shall be at least 12 inches
(30 cm) wide. There is no minimum width requirement for boatswains'
chairs.
(ii) Where scaffolds must be used in areas that the employer can
demonstrate are so narrow that platforms and walkways cannot be at
least 18 inches (46 cm) wide, such platforms and walkways shall be as
wide as feasible, and employees on those platforms and walkways shall
be protected from fall hazards by the use of guardrails and/or personal
fall arrest systems.
(3) Except as provided in paragraphs (b)(3) (i) and (ii) of this
section, the front edge of all platforms shall not be more than 14
inches (36 cm) from the face of the work, unless guardrail systems are
erected along the front edge and/or personal fall arrest systems are
used in accordance with paragraph (g) of this section to protect
employees from falling.
(i) The maximum distance from the face for outrigger scaffolds
shall be 3 inches (8 cm);
(ii) The maximum distance from the face for plastering and lathing
operations shall be 18 inches (46 cm).
(4) Each end of a platform, unless cleated or otherwise restrained
by hooks or equivalent means, shall extend over the centerline of its
support at least 6 inches (15 cm).
(5)(i) Each end of a platform 10 feet or less in length shall not
extend over its support more than 12 inches (30 cm) unless the platform
is designed and installed so that the cantilevered portion of the
platform is able to support employees and/or materials without tipping,
or has guardrails which block employee access to the cantilevered end.
(ii) Each platform greater than 10 feet in length shall not extend
over its support more than 18 inches (46 cm), unless it is designed and
installed so that the cantilevered portion of the platform is able to
support employees without tipping, or has guardrails which block
employee access to the cantilevered end.
(6) On scaffolds where scaffold planks are abutted to create a long
platform, each abutted end shall rest on a separate support surface.
This provision does not preclude the use of common support members,
such as ``T'' sections, to support abutting planks, or hook on
platforms designed to rest on common supports.
(7) On scaffolds where platforms are overlapped to create a long
platform, the overlap shall occur only over supports, and shall not be
less than 12 inches (30 cm) unless the platforms are nailed together or
otherwise restrained to prevent movement.
(8) At all points of a scaffold where the platform changes
direction, such as turning a corner, any platform that rests on a
bearer at an angle other than a right angle shall be laid first, and
platforms which rest at right angles over the same bearer shall be laid
second, on top of the first platform.
(9) Wood platforms shall not be covered with opaque finishes,
except that platform edges may be covered or marked for identification.
Platforms may be coated periodically with wood preservatives, fire-
retardant finishes, and slip-resistant finishes; however, the coating
may not obscure the top or bottom wood surfaces.
(10) Scaffold components manufactured by different manufacturers
shall not be intermixed unless the components fit together without
force and the scaffold's structural integrity is maintained by the
[[Page 46108]]
user. Scaffold components manufactured by different manufacturers shall
not be modified in order to intermix them unless a competent person
determines the resulting scaffold is structurally sound.
(11) Scaffold components made of dissimilar metals shall not be
used together unless a competent person has determined that galvanic
action will not reduce the strength of any component to a level below
that required by paragraph (a)(1) of this section.
(c) Criteria for supported scaffolds. (1) Supported scaffolds with
a height to base width (including outrigger supports, if used) ratio of
more than four to one (4:1) shall be restrained from tipping by guying,
tying, bracing, or equivalent means, as follows:
(i) Guys, ties, and braces shall be installed at locations where
horizontal members support both inner and outer legs.
(ii) Guys, ties, and braces shall be installed according to the
scaffold manufacturer's recommendations or at the closest horizontal
member to the 4:1 height and be repeated vertically at locations of
horizontal members every 20 feet (6.1 m) or less thereafter for
scaffolds 3 feet (0.91 m) wide or less, and every 26 feet (7.9 m) or
less thereafter for scaffolds greater than 3 feet (0.91 m) wide. The
top guy, tie or brace of completed scaffolds shall be placed no further
than the 4:1 height from the top. Such guys, ties and braces shall be
installed at each end of the scaffold and at horizontal intervals not
to exceed 30 feet (9.1 m) (measured from one end [not both] towards the
other).
(iii) Ties, guys, braces, or outriggers shall be used to prevent
the tipping of supported scaffolds in all circumstances where an
eccentric load, such as a cantilevered work platform, is applied or is
transmitted to the scaffold.
(2) Supported scaffold poles, legs, posts, frames, and uprights
shall bear on base plates, mud sills or other adequate firm foundation.
(i) Footings shall be level, sound, rigid, and capable of
supporting the loaded scaffold without settling or displacement.
(ii) Unstable objects shall not be used to support scaffolds or
platform units.
(iii) Unstable objects shall not be used as working platforms.
(iv) Front-end loaders and similar pieces of equipment shall not be
used to support scaffold platforms unless they have been specifically
designed by the manufacturer for such use.
(v) Fork-lifts shall not be used to support scaffold platforms
unless the entire platform is attached to the fork and the fork-lift is
not moved horizontally while the platform is occupied.
(3) Supported scaffold poles, legs, posts, frames, and uprights
shall be plumb and braced to prevent swaying and displacement.
(d) Criteria for suspension scaffolds. (1) All suspension scaffold
support devices, such as outrigger beams, cornice hooks, parapet
clamps, and similar devices, shall rest on surfaces capable of
supporting at least 4 times the load imposed on them by the scaffold
operating at the rated load of the hoist (or at least 1.5 times the
load imposed on them by the scaffold at the stall capacity of the
hoist, whichever is greater).
(2) Suspension scaffold outrigger beams, when used, shall be made
of structural metal or equivalent strength material, and shall be
restrained to prevent movement.
(3) The inboard ends of suspension scaffold outrigger beams shall
be stabilized by bolts or other direct connections to the floor or roof
deck, or they shall have their inboard ends stabilized by
counterweights, except masons' multi-point adjustable suspension
scaffold outrigger beams shall not be stabilized by counterweights.
(i) Before the scaffold is used, direct connections shall be
evaluated by a competent person who shall confirm, based on the
evaluation, that the supporting surfaces are capable of supporting the
loads to be imposed. In addition, masons' multi-point adjustable
suspension scaffold connections shall be designed by an engineer
experienced in such scaffold design.
(ii) Counterweights shall be made of non-flowable material. Sand,
gravel and similar materials that can be easily dislocated shall not be
used as counterweights.
(iii) Only those items specifically designed as counterweights
shall be used to counterweight scaffold systems. Construction materials
such as, but not limited to, masonry units and rolls of roofing felt,
shall not be used as counterweights.
(iv) Counterweights shall be secured by mechanical means to the
outrigger beams to prevent accidental displacement.
(v) Counterweights shall not be removed from an outrigger beam
until the scaffold is disassembled.
(vi) Outrigger beams which are not stabilized by bolts or other
direct connections to the floor or roof deck shall be secured by
tiebacks.
(vii) Tiebacks shall be equivalent in strength to the suspension
ropes.
(viii) Outrigger beams shall be placed perpendicular to its bearing
support (usually the face of the building or structure). However, where
the employer can demonstrate that it is not possible to place an
outrigger beam perpendicular to the face of the building or structure
because of obstructions that cannot be moved, the outrigger beam may be
placed at some other angle, provided opposing angle tiebacks are used.
(ix) Tiebacks shall be secured to a structurally sound anchorage on
the building or structure. Sound anchorages include structural members,
but do not include standpipes, vents, other piping systems, or
electrical conduit.
(x) Tiebacks shall be installed perpendicular to the face of the
building or structure, or opposing angle tiebacks shall be installed.
Single tiebacks installed at an angle are prohibited.
(4) Suspension scaffold outrigger beams shall be:
(i) Provided with stop bolts or shackles at both ends;
(ii) Securely fastened together with the flanges turned out when
channel iron beams are used in place of I-beams;
(iii) Installed with all bearing supports perpendicular to the beam
center line;
(iv) Set and maintained with the web in a vertical position; and
(v) When an outrigger beam is used, the shackle or clevis with
which the rope is attached to the outrigger beam shall be placed
directly over the center line of the stirrup.
(5) Suspension scaffold support devices such as cornice hooks, roof
hooks, roof irons, parapet clamps, or similar devices shall be:
(i) Made of steel, wrought iron, or materials of equivalent
strength;
(ii) Supported by bearing blocks; and
(iii) Secured against movement by tiebacks installed at right
angles to the face of the building or structure, or opposing angle
tiebacks shall be installed and secured to a structurally sound point
of anchorage on the building or structure. Sound points of anchorage
include structural members, but do not include standpipes, vents, other
piping systems, or electrical conduit.
(iv) Tiebacks shall be equivalent in strength to the hoisting rope.
(6) When winding drum hoists are used on a suspension scaffold,
they shall contain not less than four wraps of the suspension rope at
the lowest point of scaffold travel. When other types of hoists are
used, the suspension ropes shall be long enough to allow the scaffold
to be lowered to the level below without the rope end passing through
[[Page 46109]]
the hoist, or the rope end shall be configured or provided with means
to prevent the end from passing through the hoist.
(7) The use of repaired wire rope as suspension rope is prohibited.
(8) Wire suspension ropes shall not be joined together except
through the use of eye splice thimbles connected with shackles or
coverplates and bolts.
(9) The load end of wire suspension ropes shall be equipped with
proper size thimbles and secured by eyesplicing or equivalent means.
(10) Ropes shall be inspected for defects by a competent person
prior to each workshift and after every occurrence which could affect a
rope's integrity. Ropes shall be replaced if any of the following
conditions exist:
(i) Any physical damage which impairs the function and strength of
the rope.
(ii) Kinks that might impair the tracking or wrapping of rope
around the drum(s) or sheave(s).
(iii) Six randomly distributed broken wires in one rope lay or
three broken wires in one strand in one rope lay.
(iv) Abrasion, corrosion, scrubbing, flattening or peening causing
loss of more than one-third of the original diameter of the outside
wires.
(v) Heat damage caused by a torch or any damage caused by contact
with electrical wires.
(vi) Evidence that the secondary brake has been activated during an
overspeed condition and has engaged the suspension rope.
(11) Swaged attachments or spliced eyes on wire suspension ropes
shall not be used unless they are made by the wire rope manufacturer or
a qualified person.
(12) When wire rope clips are used on suspension scaffolds:
(i) There shall be a minimum of 3 wire rope clips installed, with
the clips a minimum of 6 rope diameters apart;
(ii) Clips shall be installed according to the manufacturer's
recommendations;
(iii) Clips shall be retightened to the manufacturer's
recommendations after the initial loading;
(iv) Clips shall be inspected and retightened to the manufacturer's
recommendations at the start of each workshift thereafter;
(v) U-bolt clips shall not be used at the point of suspension for
any scaffold hoist;
(vi) When U-bolt clips are used, the U-bolt shall be placed over
the dead end of the rope, and the saddle shall be placed over the live
end of the rope.
(13) Suspension scaffold power-operated hoists and manual hoists
shall be tested and listed by a qualified testing laboratory.
(14) Gasoline-powered equipment and hoists shall not be used on
suspension scaffolds.
(15) Gears and brakes of power-operated hoists used on suspension
scaffolds shall be enclosed.
(16) In addition to the normal operating brake, suspension scaffold
power-operated hoists and manually operated hoists shall have a braking
device or locking pawl which engages automatically when a hoist makes
either of the following uncontrolled movements: an instantaneous change
in momentum or an accelerated overspeed.
(17) Manually operated hoists shall require a positive crank force
to descend.
(18) Two-point and multi-point suspension scaffolds shall be tied
or otherwise secured to prevent them from swaying, as determined to be
necessary based on an evaluation by a competent person. Window
cleaners' anchors shall not be used for this purpose.
(19) Devices whose sole function is to provide emergency escape and
rescue shall not be used as working platforms. This provision does not
preclude the use of systems which are designed to function both as
suspension scaffolds and emergency systems.
(e) Access. This paragraph applies to scaffold access for all
employees. Access requirements for employees erecting or dismantling
supported scaffolds are specifically addressed in paragraph (e)(9) of
this section.
(1) When scaffold platforms are more than 2 feet (0.6 m) above or
below a point of access, portable ladders, hook-on ladders, attachable
ladders, stair towers (scaffold stairways/towers), stairway-type
ladders (such as ladder stands), ramps, walkways, integral
prefabricated scaffold access, or direct access from another scaffold,
structure, personnel hoist, or similar surface shall be used.
Crossbraces shall not be used as a means of access.
(2) Portable, hook-on, and attachable ladders (Additional
requirements for the proper construction and use of portable ladders
are contained in subpart X of this part--Stairways and Ladders):
(i) Portable, hook-on, and attachable ladders shall be positioned
so as not to tip the scaffold;
(ii) Hook-on and attachable ladders shall be positioned so that
their bottom rung is not more than 24 inches (61 cm) above the scaffold
supporting level;
(iii) When hook-on and attachable ladders are used on a supported
scaffold more than 35 feet (10.7 m) high, they shall have rest
platforms at 35-foot (10.7 m) maximum vertical intervals.
(iv) Hook-on and attachable ladders shall be specifically designed
for use with the type of scaffold used;
(v) Hook-on and attachable ladders shall have a minimum rung length
of 11\1/2\ inches (29 cm); and
(vi) Hook-on and attachable ladders shall have uniformly spaced
rungs with a maximum spacing between rungs of 16\3/4\ inches.
(3) Stairway-type ladders shall:
(i) Be positioned such that their bottom step is not more than 24
inches (61 cm) above the scaffold supporting level;
(ii) Be provided with rest platforms at 12 foot (3.7 m) maximum
vertical intervals;
(iii) Have a minimum step width of 16 inches (41 cm), except that
mobile scaffold stairway-type ladders shall have a minimum step width
of 11\1/2\ inches (30 cm); and
(iv) Have slip-resistant treads on all steps and landings.
(4) Stairtowers (scaffold stairway/towers) shall be positioned such
that their bottom step is not more than 24 inches (61 cm.) above the
scaffold supporting level.
(i) A stairrail consisting of a toprail and a midrail shall be
provided on each side of each scaffold stairway.
(ii) The toprail of each stairrail system shall also be capable of
serving as a handrail, unless a separate handrail is provided.
(iii) Handrails, and toprails that serve as handrails, shall
provide an adequate handhold for employees grasping them to avoid
falling.
(iv) Stairrail systems and handrails shall be surfaced to prevent
injury to employees from punctures or lacerations, and to prevent
snagging of clothing.
(v) The ends of stairrail systems and handrails shall be
constructed so that they do not constitute a projection hazard.
(vi) Handrails, and toprails that are used as handrails, shall be
at least 3 inches (7.6 cm) from other objects.
(vii) Stairrails shall be not less than 28 inches (71 cm) nor more
than 37 inches (94 cm) from the upper surface of the stairrail to the
surface of the tread, in line with the face of the riser at the forward
edge of the tread.
(viii) A landing platform at least 18 inches (45.7 cm) wide by at
least 18 inches (45.7 cm) long shall be provided at each level.
(ix) Each scaffold stairway shall be at least 18 inches (45.7 cm)
wide between stairrails.
(x) Treads and landings shall have slip-resistant surfaces.
[[Page 46110]]
(xi) Stairways shall be installed between 40 degrees and 60 degrees
from the horizontal.
(xii) Guardrails meeting the requirements of paragraph (g)(4) of
this section shall be provided on the open sides and ends of each
landing.
(xiii) Riser height shall be uniform, within \1/4\ inch, (0.6 cm)
for each flight of stairs. Greater variations in riser height are
allowed for the top and bottom steps of the entire system, not for each
flight of stairs.
(xiv) Tread depth shall be uniform, within \1/4\ inch, for each
flight of stairs.
(5) Ramps and walkways. (i) Ramps and walkways 6 feet (1.8 m) or
more above lower levels shall have guardrail systems which comply with
subpart M of this part--Fall Protection;
(ii) No ramp or walkway shall be inclined more than a slope of one
(1) vertical to three (3) horizontal (20 degrees above the horizontal).
(iii) If the slope of a ramp or a walkway is steeper than one (1)
vertical in eight (8) horizontal, the ramp or walkway shall have cleats
not more than fourteen (14) inches (35 cm) apart which are securely
fastened to the planks to provide footing.
(6) Integral prefabricated scaffold access frames shall:
(i) Be specifically designed and constructed for use as ladder
rungs;
(ii) Have a rung length of at least 8 inches (20 cm);
(iii) Not be used as work platforms when rungs are less than 11\1/
2\ inches in length, unless each affected employee uses fall
protection, or a positioning device, which complies with Sec. 1926.502;
(iv) Be uniformly spaced within each frame section;
(v) Be provided with rest platforms at 35-foot (10.7 m) maximum
vertical intervals on all supported scaffolds more than 35 feet (10.7
m) high; and
(vi) Have a maximum spacing between rungs of 16\3/4\ inches (43
cm). Non-uniform rung spacing caused by joining end frames together is
allowed, provided the resulting spacing does not exceed 16\3/4\ inches
(43 cm).
(7) Steps and rungs of ladder and stairway type access shall line
up vertically with each other between rest platforms.
(8) Direct access to or from another surface shall be used only
when the scaffold is not more than 14 inches (36 cm) horizontally and
not more than 24 inches (61 cm) vertically from the other surface.
(9) Effective September 2, 1997, access for employees erecting or
dismantling supported scaffolds shall be in accordance with the
following:
(i) The employer shall provide safe means of access for each
employee erecting or dismantling a scaffold where the provision of safe
access is feasible and does not create a greater hazard. The employer
shall have a competent person determine whether it is feasible or would
pose a greater hazard to provide, and have employees use a safe means
of access. This determination shall be based on site conditions and the
type of scaffold being erected or dismantled.
(ii) Hook-on or attachable ladders shall be installed as soon as
scaffold erection has progressed to a point that permits safe
installation and use.
(iii) When erecting or dismantling tubular welded frame scaffolds,
(end) frames, with horizontal members that are parallel, level and are
not more than 22 inches apart vertically may be used as climbing
devices for access, provided they are erected in a manner that creates
a usable ladder and provides good hand hold and foot space.
(iv) Cross braces on tubular welded frame scaffolds shall not be
used as a means of access or egress.
(f) Use. (1) Scaffolds and scaffold components shall not be loaded
in excess of their maximum intended loads or rated capacities,
whichever is less.
(2) The use of shore or lean-to scaffolds is prohibited.
(3) Scaffolds and scaffold components shall be inspected for
visible defects by a competent person before each work shift, and after
any occurrence which could affect a scaffold's structural integrity.
(4) Any part of a scaffold damaged or weakened such that its
strength is less than that required by paragraph (a) of this section
shall be immediately repaired or replaced, braced to meet those
provisions, or removed from service until repaired.
(5) Scaffolds shall not be moved horizontally while employees are
on them, unless they have been designed by a registered professional
engineer specifically for such movement or, for mobile scaffolds, where
the provisions of Sec. 1926.452(w) are followed.
(6) The clearance between scaffolds and power lines shall be as
follows: Scaffolds shall not be erected, used, dismantled, altered, or
moved such that they or any conductive material handled on them might
come closer to exposed and energized power lines than as follows:
----------------------------------------------------------------------------------------------------------------
Insulated lines voltage Minimum distance Alternatives
----------------------------------------------------------------------------------------------------------------
Less than 300 volts................ 3 feet (0.9 M).......................
More than 50 kv.................... 10 feet (3.1 M) plus 4.0 inches (10 2 times the length of the line
cm) for each 1 kv over 50 kv. insulator, but never less than 10
feet (3.1 m).
----------------------------------------------------------------------------------------------------------------
----------------------------------------------------------------------------------------------------------------
Uninsulated lines voltage Minimum distance Alternatives
----------------------------------------------------------------------------------------------------------------
Less than 50 kv.................... 10 feet (3.1 M)......................
More than 50 kv.................... 10 feet (3.1 M) plus 4.0 inches (10 2 times the length of the line
cm) for each 1 kv over 50 kv. insulator, but never less than 10
feet (3.1 m).
----------------------------------------------------------------------------------------------------------------
Exception to paragraph (b)(6): Scaffolds and materials may be
closer to power lines than specified above where such clearance is
necessary for performance of work, and only after the utility company,
or electrical system operator, has been notified of the need to work
closer and the utility company, or electrical system operator, has
deenergized the lines, relocated the lines, or installed protective
coverings to prevent accidental contact with the lines.
(7) Scaffolds shall be erected, moved, dismantled, or altered only
under the supervision and direction of a competent person qualified in
scaffold erection, moving, dismantling or alteration. Such activities
shall be performed only by experienced and trained employees selected
for such work by the competent person.
(8) Employees shall be prohibited from working on scaffolds covered
with snow, ice, or other slippery material except as necessary for
removal of such materials.
[[Page 46111]]
(9) Where swinging loads are being hoisted onto or near scaffolds
such that the loads might contact the scaffold, tag lines or equivalent
measures to control the loads shall be used.
(10) Suspension ropes supporting adjustable suspension scaffolds
shall be of a diameter large enough to provide sufficient surface area
for the functioning of brake and hoist mechanisms.
(11) Suspension ropes shall be shielded from heat-producing
processes. When acids or other corrosive substances are used on a
scaffold, the ropes shall be shielded, treated to protect against the
corrosive substances, or shall be of a material that will not be
damaged by the substance being used.
(12) Work on or from scaffolds is prohibited during storms or high
winds unless a competent person has determined that it is safe for
employees to be on the scaffold and those employees are protected by a
personal fall arrest system or wind screens. Wind screens shall not be
used unless the scaffold is secured against the anticipated wind forces
imposed.
(13) Debris shall not be allowed to accumulate on platforms.
(14) Makeshift devices, such as but not limited to boxes and
barrels, shall not be used on top of scaffold platforms to increase the
working level height of employees.
(15) Ladders shall not be used on scaffolds to increase the working
level height of employees, except on large area scaffolds where
employers have satisfied the following criteria:
(i) When the ladder is placed against a structure which is not a
part of the scaffold, the scaffold shall be secured against the
sideways thrust exerted by the ladder;
(ii) The platform units shall be secured to the scaffold to prevent
their movement;
(iii) The ladder legs shall be on the same platform or other means
shall be provided to stabilize the ladder against unequal platform
deflection, and
(iv) The ladder legs shall be secured to prevent them from slipping
or being pushed off the platform.
(16) Platforms shall not deflect more than \1/60\ of the span when
loaded.
(17) To reduce the possibility of welding current arcing through
the suspension wire rope when performing welding from suspended
scaffolds, the following precautions shall be taken, as applicable:
(i) An insulated thimble shall be used to attach each suspension
wire rope to its hanging support (such as cornice hook or outrigger).
Excess suspension wire rope and any additional independent lines from
grounding shall be insulated;
(ii) The suspension wire rope shall be covered with insulating
material extending at least 4 feet (1.2 m) above the hoist. If there is
a tail line below the hoist, it shall be insulated to prevent contact
with the platform. The portion of the tail line that hangs free below
the scaffold shall be guided or retained, or both, so that it does not
become grounded;
(iii) Each hoist shall be covered with insulated protective covers;
(iv) In addition to a work lead attachment required by the welding
process, a grounding conductor shall be connected from the scaffold to
the structure. The size of this conductor shall be at least the size of
the welding process work lead, and this conductor shall not be in
series with the welding process or the work piece;
(v) If the scaffold grounding lead is disconnected at any time, the
welding machine shall be shut off; and
(vi) An active welding rod or uninsulated welding lead shall not be
allowed to contact the scaffold or its suspension system.
(g) Fall protection. (1) Each employee on a scaffold more than 10
feet (3.1 m) above a lower level shall be protected from falling to
that lower level. Paragraphs (g)(1) (i) through (vii) of this section
establish the types of fall protection to be provided to the employees
on each type of scaffold. Paragraph (g)(2) of this section addresses
fall protection for scaffold erectors and dismantlers.
Note to paragraph (g)(1): The fall protection requirements for
employees installing suspension scaffold support systems on floors,
roofs, and other elevated surfaces are set forth in subpart M of
this part.
(i) Each employee on a boatswains' chair, catenary scaffold, float
scaffold, needle beam scaffold, or ladder jack scaffold shall be
protected by a personal fall arrest system;
(ii) Each employee on a single-point or two-point adjustable
suspension scaffold shall be protected by both a personal fall arrest
system and guardrail system;
(iii) Each employee on a crawling board (chicken ladder) shall be
protected by a personal fall arrest system, a guardrail system (with
minimum 200 pound toprail capacity), or by a three-fourth inch (1.9 cm)
diameter grabline or equivalent handhold securely fastened beside each
crawling board;
(iv) Each employee on a self-contained adjustable scaffold shall be
protected by a guardrail system (with minimum 200 pound toprail
capacity) when the platform is supported by the frame structure, and by
both a personal fall arrest system and a guardrail system (with minimum
200 pound toprail capacity) when the platform is supported by ropes;
(v) Each employee on a walkway located within a scaffold shall be
protected by a guardrail system (with minimum 200 pound toprail
capacity) installed within 9\1/2\ inches (24.1 cm) of and along at
least one side of the walkway.
(vi) Each employee performing overhand bricklaying operations from
a supported scaffold shall be protected from falling from all open
sides and ends of the scaffold (except at the side next to the wall
being laid) by the use of a personal fall arrest system or guardrail
system (with minimum 200 pound toprail capacity).
(vii) For all scaffolds not otherwise specified in paragraphs
(g)(1)(i) through (g)(1)(vi) of this section, each employee shall be
protected by the use of personal fall arrest systems or guardrail
systems meeting the requirements of paragraph (g)(4) of this section.
(2) Effective September 2, 1997, the employer shall have a
competent person determine the feasibility and safety of providing fall
protection for employees erecting or dismantling supported scaffolds.
Employers are required to provide fall protection for employees
erecting or dismantling supported scaffolds where the installation and
use of such protection is feasible and does not create a greater
hazard.
(3) In addition to meeting the requirements of Sec. 1926.502(d),
personal fall arrest systems used on scaffolds shall be attached by
lanyard to a vertical lifeline, horizontal lifeline, or scaffold
structural member. Vertical lifelines shall not be used when overhead
components, such as overhead protection or additional platform levels,
are part of a single-point or two-point adjustable suspension scaffold.
(i) When vertical lifelines are used, they shall be fastened to a
fixed safe point of anchorage, shall be independent of the scaffold,
and shall be protected from sharp edges and abrasion. Safe points of
anchorage include structural members of buildings, but do not include
standpipes, vents, other piping systems, electrical conduit, outrigger
beams, or counterweights.
(ii) When horizontal lifelines are used, they shall be secured to
two or more structural members of the scaffold, or they may be looped
around both suspension and independent
[[Page 46112]]
suspension lines (on scaffolds so equipped) above the hoist and brake
attached to the end of the scaffold. Horizontal lifelines shall not be
attached only to the suspension ropes.
(iii) When lanyards are connected to horizontal lifelines or
structural members on a single-point or two-point adjustable suspension
scaffold, the scaffold shall be equipped with additional independent
support lines and automatic locking devices capable of stopping the
fall of the scaffold in the event one or both of the suspension ropes
fail. The independent support lines shall be equal in number and
strength to the suspension ropes.
(iv) Vertical lifelines, independent support lines, and suspension
ropes shall not be attached to each other, nor shall they be attached
to or use the same point of anchorage, nor shall they be attached to
the same point on the scaffold or personal fall arrest system.
(4) Guardrail systems installed to meet the requirements of this
section shall comply with the following provisions (guardrail systems
built in accordance with Appendix A to this subpart will be deemed to
meet the requirements of paragraphs (g)(4) (vii), (viii), and (ix) of
this section):
(i) Guardrail systems shall be installed along all open sides and
ends of platforms. Guardrail systems shall be installed before the
scaffold is released for use by employees other than erection/
dismantling crews.
(ii) The top edge height of toprails or equivalent member on
supported scaffolds manufactured or placed in service after January 1,
2000 shall be installed between 38 inches (0.97 m) and 45 inches (1.2
m) above the platform surface. The top edge height on supported
scaffolds manufactured and placed in service before January 1, 2000,
and on all suspended scaffolds where both a guardrail and a personal
fall arrest system are required shall be between 36 inches (0.9 m) and
45 inches (1.2 m). When conditions warrant, the height of the top edge
may exceed the 45-inch height, provided the guardrail system meets all
other criteria of paragraph (g)(4).
(iii) When midrails, screens, mesh, intermediate vertical members,
solid panels, or equivalent structural members are used, they shall be
installed between the top edge of the guardrail system and the scaffold
platform.
(iv) When midrails are used, they shall be installed at a height
approximately midway between the top edge of the guardrail system and
the platform surface.
(v) When screens and mesh are used, they shall extend from the top
edge of the guardrail system to the scaffold platform, and along the
entire opening between the supports.
(vi) When intermediate members (such as balusters or additional
rails) are used, they shall not be more than 19 inches (48 cm) apart.
(vii) Each toprail or equivalent member of a guardrail system shall
be capable of withstanding, without failure, a force applied in any
downward or horizontal direction at any point along its top edge of at
least 100 pounds (445 n) for guardrail systems installed on single-
point adjustable suspension scaffolds or two-point adjustable
suspension scaffolds, and at least 200 pounds (890 n) for guardrail
systems installed on all other scaffolds.
(viii) When the loads specified in paragraph (g)(4)(vii) of this
section are applied in a downward direction, the top edge shall not
drop below the height above the platform surface that is prescribed in
paragraph (g)(4)(ii) of this section.
(ix) Midrails, screens, mesh, intermediate vertical members, solid
panels, and equivalent structural members of a guardrail system shall
be capable of withstanding, without failure, a force applied in any
downward or horizontal direction at any point along the midrail or
other member of at least 75 pounds (333 n) for guardrail systems with a
minimum 100 pound toprail capacity, and at least 150 pounds (666 n) for
guardrail systems with a minimum 200 pound toprail capacity.
(x) Suspension scaffold hoists and non-walk-through stirrups may be
used as end guardrails, if the space between the hoist or stirrup and
the side guardrail or structure does not allow passage of an employee
to the end of the scaffold.
(xi) Guardrails shall be surfaced to prevent injury to an employee
from punctures or lacerations, and to prevent snagging of clothing.
(xii) The ends of all rails shall not overhang the terminal posts
except when such overhang does not constitute a projection hazard to
employees.
(xiii) Steel or plastic banding shall not be used as a toprail or
midrail.
(xiv) Manila or plastic (or other synthetic) rope being used for
toprails or midrails shall be inspected by a competent person as
frequently as necessary to ensure that it continues to meet the
strength requirements of paragraph (g) of this section.
(xv) Crossbracing is acceptable in place of a midrail when the
crossing point of two braces is between 20 inches (0.5 m) and 30 inches
(0.8 m) above the work platform or as a toprail when the crossing point
of two braces is between 38 inches (0.97 m) and 48 inches (1.3 m) above
the work platform. The end points at each upright shall be no more than
48 inches (1.3 m) apart.
(h) Falling object protection. (1) In addition to wearing hardhats
each employee on a scaffold shall be provided with additional
protection from falling hand tools, debris, and other small objects
through the installation of toeboards, screens, or guardrail systems,
or through the erection of debris nets, catch platforms, or canopy
structures that contain or deflect the falling objects. When the
falling objects are too large, heavy or massive to be contained or
deflected by any of the above-listed measures, the employer shall place
such potential falling objects away from the edge of the surface from
which they could fall and shall secure those materials as necessary to
prevent their falling.
(2) Where there is a danger of tools, materials, or equipment
falling from a scaffold and striking employees below, the following
provisions apply:
(i) The area below the scaffold to which objects can fall shall be
barricaded, and employees shall not be permitted to enter the hazard
area; or
(ii) A toeboard shall be erected along the edge of platforms more
than 10 feet (3.1 m) above lower levels for a distance sufficient to
protect employees below, except on float (ship) scaffolds where an
edging of \3/4\ x 1\1/2\ inch (2 x 4 cm) wood or equivalent may be
used in lieu of toeboards;
(iii) Where tools, materials, or equipment are piled to a height
higher than the top edge of the toeboard, paneling or screening
extending from the toeboard or platform to the top of the guardrail
shall be erected for a distance sufficient to protect employees below;
or
(iv) A guardrail system shall be installed with openings small
enough to prevent passage of potential falling objects; or
(v) A canopy structure, debris net, or catch platform strong enough
to withstand the impact forces of the potential falling objects shall
be erected over the employees below.
(3) Canopies, when used for falling object protection, shall comply
with the following criteria:
(i) Canopies shall be installed between the falling object hazard
and the employees.
(ii) When canopies are used on suspension scaffolds for falling
object protection, the scaffold shall be equipped with additional
independent
[[Page 46113]]
support lines equal in number to the number of points supported, and
equivalent in strength to the strength of the suspension ropes.
(iii) Independent support lines and suspension ropes shall not be
attached to the same points of anchorage.
(4) Where used, toeboards shall be:
(i) Capable of withstanding, without failure, a force of at least
50 pounds (222 n) applied in any downward or horizontal direction at
any point along the toeboard (toeboards built in accordance with
Appendix A to this subpart will be deemed to meet this requirement);
and
(ii) At least three and one-half inches (9 cm) high from the top
edge of the toeboard to the level of the walking/working surface.
Toeboards shall be securely fastened in place at the outermost edge of
the platform and have not more than \1/4\ inch (0.7 cm) clearance above
the walking/working surface. Toeboards shall be solid or with openings
not over one inch (2.5 cm) in the greatest dimension.
Sec. 1926.452 Additional requirements applicable to specific types of
scaffolds.
In addition to the applicable requirements of Sec. 1926.451, the
following requirements apply to the specific types of scaffolds
indicated. Scaffolds not specifically addressed by Sec. 1926.452, such
as but not limited to systems scaffolds, must meet the requirements of
Sec. 1926.451.
(a) Pole scaffolds. (1) When platforms are being moved to the next
level, the existing platform shall be left undisturbed until the new
bearers have been set in place and braced, prior to receiving the new
platforms.
(2) Crossbracing shall be installed between the inner and outer
sets of poles on double pole scaffolds.
(3) Diagonal bracing in both directions shall be installed across
the entire inside face of double-pole scaffolds used to support loads
equivalent to a uniformly distributed load of 50 pounds (222 kg) or
more per square foot (929 square cm).
(4) Diagonal bracing in both directions shall be installed across
the entire outside face of all double- and single-pole scaffolds.
(5) Runners and bearers shall be installed on edge.
(6) Bearers shall extend a minimum of 3 inches (7.6 cm) over the
outside edges of runners.
(7) Runners shall extend over a minimum of two poles, and shall be
supported by bearing blocks securely attached to the poles.
(8) Braces, bearers, and runners shall not be spliced between
poles.
(9) Where wooden poles are spliced, the ends shall be squared and
the upper section shall rest squarely on the lower section. Wood splice
plates shall be provided on at least two adjacent sides, and shall
extend at least 2 feet (0.6 m) on either side of the splice, overlap
the abutted ends equally, and have at least the same cross-sectional
areas as the pole. Splice plates of other materials of equivalent
strength may be used.
(10) Pole scaffolds over 60 feet in height shall be designed by a
registered professional engineer, and shall be constructed and loaded
in accordance with that design. Non-mandatory Appendix A to this
subpart contains examples of criteria that will enable an employer to
comply with design and loading requirements for pole scaffolds under 60
feet in height.
(b) Tube and coupler scaffolds. (1) When platforms are being moved
to the next level, the existing platform shall be left undisturbed
until the new bearers have been set in place and braced prior to
receiving the new platforms.
(2) Transverse bracing forming an ``X'' across the width of the
scaffold shall be installed at the scaffold ends and at least at every
third set of posts horizontally (measured from only one end) and every
fourth runner vertically. Bracing shall extend diagonally from the
inner or outer posts or runners upward to the next outer or inner posts
or runners. Building ties shall be installed at the bearer levels
between the transverse bracing and shall conform to the requirements of
Sec. 1926.451(c)(1).
(3) On straight run scaffolds, longitudinal bracing across the
inner and outer rows of posts shall be installed diagonally in both
directions, and shall extend from the base of the end posts upward to
the top of the scaffold at approximately a 45 degree angle. On
scaffolds whose length is greater than their height, such bracing shall
be repeated beginning at least at every fifth post. On scaffolds whose
length is less than their height, such bracing shall be installed from
the base of the end posts upward to the opposite end posts, and then in
alternating directions until reaching the top of the scaffold. Bracing
shall be installed as close as possible to the intersection of the
bearer and post or runner and post.
(4) Where conditions preclude the attachment of bracing to posts,
bracing shall be attached to the runners as close to the post as
possible.
(5) Bearers shall be installed transversely between posts, and when
coupled to the posts, shall have the inboard coupler bear directly on
the runner coupler. When the bearers are coupled to the runners, the
couplers shall be as close to the posts as possible.
(6) Bearers shall extend beyond the posts and runners, and shall
provide full contact with the coupler.
(7) Runners shall be installed along the length of the scaffold,
located on both the inside and outside posts at level heights (when
tube and coupler guardrails and midrails are used on outside posts,
they may be used in lieu of outside runners).
(8) Runners shall be interlocked on straight runs to form
continuous lengths, and shall be coupled to each post. The bottom
runners and bearers shall be located as close to the base as possible.
(9) Couplers shall be of a structural metal, such as drop-forged
steel, malleable iron, or structural grade aluminum. The use of gray
cast iron is prohibited.
(10) Tube and coupler scaffolds over 125 feet in height shall be
designed by a registered professional engineer, and shall be
constructed and loaded in accordance with such design. Non-mandatory
Appendix A to this subpart contains examples of criteria that will
enable an employer to comply with design and loading requirements for
tube and coupler scaffolds under 125 feet in height.
(c) Fabricated frame scaffolds (tubular welded frame scaffolds).
(1) When moving platforms to the next level, the existing platform
shall be left undisturbed until the new end frames have been set in
place and braced prior to receiving the new platforms.
(2) Frames and panels shall be braced by cross, horizontal, or
diagonal braces, or combination thereof, which secure vertical members
together laterally. The cross braces shall be of such length as will
automatically square and align vertical members so that the erected
scaffold is always plumb, level, and square. All brace connections
shall be secured.
(3) Frames and panels shall be joined together vertically by
coupling or stacking pins or equivalent means.
(4) Where uplift can occur which would displace scaffold end frames
or panels, the frames or panels shall be locked together vertically by
pins or equivalent means.
(5) Brackets used to support cantilevered loads shall:
(i) Be seated with side-brackets parallel to the frames and end-
brackets at 90 degrees to the frames;
(ii) Not be bent or twisted from these positions; and
(iii) Be used only to support personnel, unless the scaffold has
been designed for other loads by a qualified
[[Page 46114]]
engineer and built to withstand the tipping forces caused by those
other loads being placed on the bracket-supported section of the
scaffold.
(6) Scaffolds over 125 feet (38.0 m) in height above their base
plates shall be designed by a registered professional engineer, and
shall be constructed and loaded in accordance with such design.
(d) Plasterers', decorators', and large area scaffolds. Scaffolds
shall be constructed in accordance with paragraphs (a), (b), or (c) of
this section, as appropriate.
(e) Bricklayers' square scaffolds (squares). (1) Scaffolds made of
wood shall be reinforced with gussets on both sides of each corner.
(2) Diagonal braces shall be installed on all sides of each square.
(3) Diagonal braces shall be installed between squares on the rear
and front sides of the scaffold, and shall extend from the bottom of
each square to the top of the next square.
(4) Scaffolds shall not exceed three tiers in height, and shall be
so constructed and arranged that one square rests directly above the
other. The upper tiers shall stand on a continuous row of planks laid
across the next lower tier, and shall be nailed down or otherwise
secured to prevent displacement.
(f) Horse scaffolds. (1) Scaffolds shall not be constructed or
arranged more than two tiers or 10 feet (3.0 m) in height, whichever is
less.
(2) When horses are arranged in tiers, each horse shall be placed
directly over the horse in the tier below.
(3) When horses are arranged in tiers, the legs of each horse shall
be nailed down or otherwise secured to prevent displacement.
(4) When horses are arranged in tiers, each tier shall be
crossbraced.
(g) Form scaffolds and carpenters' bracket scaffolds. (1) Each
bracket, except those for wooden bracket-form scaffolds, shall be
attached to the supporting formwork or structure by means of one or
more of the following: nails; a metal stud attachment device; welding;
hooking over a secured structural supporting member, with the form
wales either bolted to the form or secured by snap ties or tie bolts
extending through the form and securely anchored; or, for carpenters'
bracket scaffolds only, by a bolt extending through to the opposite
side of the structure's wall.
(2) Wooden bracket-form scaffolds shall be an integral part of the
form panel.
(3) Folding type metal brackets, when extended for use, shall be
either bolted or secured with a locking-type pin.
(h) Roof bracket scaffolds. (1) Scaffold brackets shall be
constructed to fit the pitch of the roof and shall provide a level
support for the platform.
(2) Brackets (including those provided with pointed metal
projections) shall be anchored in place by nails unless it is
impractical to use nails. When nails are not used, brackets shall be
secured in place with first-grade manila rope of at least three-fourth
inch (1.9 cm) diameter, or equivalent.
(i) Outrigger scaffolds. (1) The inboard end of outrigger beams,
measured from the fulcrum point to the extreme point of anchorage,
shall be not less than one and one-half times the outboard end in
length.
(2) Outrigger beams fabricated in the shape of an I-beam or channel
shall be placed so that the web section is vertical.
(3) The fulcrum point of outrigger beams shall rest on secure
bearings at least 6 inches (15.2 cm) in each horizontal dimension.
(4) Outrigger beams shall be secured in place against movement, and
shall be securely braced at the fulcrum point against tipping.
(5) The inboard ends of outrigger beams shall be securely anchored
either by means of braced struts bearing against sills in contact with
the overhead beams or ceiling, or by means of tension members secured
to the floor joists underfoot, or by both.
(6) The entire supporting structure shall be securely braced to
prevent any horizontal movement.
(7) To prevent their displacement, platform units shall be nailed,
bolted, or otherwise secured to outriggers.
(8) Scaffolds and scaffold components shall be designed by a
registered professional engineer and shall be constructed and loaded in
accordance with such design.
(j) Pump jack scaffolds. (1) Pump jack brackets, braces, and
accessories shall be fabricated from metal plates and angles. Each pump
jack bracket shall have two positive gripping mechanisms to prevent any
failure or slippage.
(2) Poles shall be secured to the structure by rigid triangular
bracing or equivalent at the bottom, top, and other points as
necessary. When the pump jack has to pass bracing already installed, an
additional brace shall be installed approximately 4 feet (1.2 m) above
the brace to be passed, and shall be left in place until the pump jack
has been moved and the original brace reinstalled.
(3) When guardrails are used for fall protection, a workbench may
be used as the toprail only if it meets all the requirements in
paragraphs (g)(4) (ii), (vii), (viii), and (xiii) of Sec. 1926.451.
(4) Work benches shall not be used as scaffold platforms.
(5) When poles are made of wood, the pole lumber shall be straight-
grained, free of shakes, large loose or dead knots, and other defects
which might impair strength.
(6) When wood poles are constructed of two continuous lengths, they
shall be joined together with the seam parallel to the bracket.
(7) When two by fours are spliced to make a pole, mending plates
shall be installed at all splices to develop the full strength of the
member.
(k) Ladder jack scaffolds. (1) Platforms shall not exceed a height
of 20 feet (6.1 m).
(2) All ladders used to support ladder jack scaffolds shall meet
the requirements of subpart X of this part--Stairways and Ladders,
except that job-made ladders shall not be used to support ladder jack
scaffolds.
(3) The ladder jack shall be so designed and constructed that it
will bear on the side rails and ladder rungs or on the ladder rungs
alone. If bearing on rungs only, the bearing area shall include a
length of at least 10 inches (25.4 cm) on each rung.
(4) Ladders used to support ladder jacks shall be placed, fastened,
or equipped with devices to prevent slipping.
(5) Scaffold platforms shall not be bridged one to another.
(l) Window jack scaffolds. (1) Scaffolds shall be securely attached
to the window opening.
(2) Scaffolds shall be used only for the purpose of working at the
window opening through which the jack is placed.
(3) Window jacks shall not be used to support planks placed between
one window jack and another, or for other elements of scaffolding.
(m) Crawling boards (chicken ladders). (1) Crawling boards shall
extend from the roof peak to the eaves when used in connection with
roof construction, repair, or maintenance.
(2) Crawling boards shall be secured to the roof by ridge hooks or
by means that meet equivalent criteria (e.g., strength and durability).
(n) Step, platform, and trestle ladder scaffolds. (1) Scaffold
platforms shall not be placed any higher than the second highest rung
or step of the ladder supporting the platform.
(2) All ladders used in conjunction with step, platform and trestle
ladder scaffolds shall meet the pertinent requirements of subpart X of
this part--Stairways and Ladders, except that job-
[[Page 46115]]
made ladders shall not be used to support such scaffolds.
(3) Ladders used to support step, platform, and trestle ladder
scaffolds shall be placed, fastened, or equipped with devices to
prevent slipping.
(4) Scaffolds shall not be bridged one to another.
(o) Single-point adjustable suspension scaffolds. (1) When two
single-point adjustable suspension scaffolds are combined to form a
two-point adjustable suspension scaffold, the resulting two-point
scaffold shall comply with the requirements for two-point adjustable
suspension scaffolds in paragraph (p) of this section.
(2) The supporting rope between the scaffold and the suspension
device shall be kept vertical unless all of the following conditions
are met:
(i) The rigging has been designed by a qualified person, and
(ii) The scaffold is accessible to rescuers, and
(iii) The supporting rope is protected to ensure that it will not
chafe at any point where a change in direction occurs, and
(iv) The scaffold is positioned so that swinging cannot bring the
scaffold into contact with another surface.
(3) Boatswains' chair tackle shall consist of correct size ball
bearings or bushed blocks containing safety hooks and properly ``eye-
spliced'' minimum five-eighth (\5/8\) inch (1.6 cm) diameter first-
grade manila rope, or other rope which will satisfy the criteria (e.g.,
strength and durability) of manila rope.
(4) Boatswains' chair seat slings shall be reeved through four
corner holes in the seat; shall cross each other on the underside of
the seat; and shall be rigged so as to prevent slippage which could
cause an out-of-level condition.
(5) Boatswains' chair seat slings shall be a minimum of five-eight
(\5/8\) inch (1.6 cm) diameter fiber, synthetic, or other rope which
will satisfy the criteria (e.g., strength, slip resistance, durability,
etc.) of first grade manila rope.
(6) When a heat-producing process such as gas or arc welding is
being conducted, boatswains' chair seat slings shall be a minimum of
three-eight (\3/8\) inch (1.0 cm) wire rope.
(7) Non-cross-laminated wood boatswains' chairs shall be reinforced
on their underside by cleats securely fastened to prevent the board
from splitting.
(p) Two-point adjustable suspension scaffolds (swing stages). The
following requirements do not apply to two-point adjustable suspension
scaffolds used as masons' or stonesetters' scaffolds. Such scaffolds
are covered by paragraph (q) of this section.
(1) Platforms shall not be more than 36 inches (0.9 m) wide unless
designed by a qualified person to prevent unstable conditions.
(2) The platform shall be securely fastened to hangers (stirrups)
by U-bolts or by other means which satisfy the requirements of
Sec. 1926.451(a).
(3) The blocks for fiber or synthetic ropes shall consist of at
least one double and one single block. The sheaves of all blocks shall
fit the size of the rope used.
(4) Platforms shall be of the ladder-type, plank-type, beam-type,
or light-metal type. Light metal-type platforms having a rated capacity
of 750 pounds or less and platforms 40 feet (12.2 m) or less in length
shall be tested and listed by a nationally recognized testing
laboratory.
(5) Two-point scaffolds shall not be bridged or otherwise connected
one to another during raising and lowering operations unless the bridge
connections are articulated (attached), and the hoists properly sized.
(6) Passage may be made from one platform to another only when the
platforms are at the same height, are abutting, and walk-through
stirrups specifically designed for this purpose are used.
(q) Multi-point adjustable suspension scaffolds, stonesetters'
multi-point adjustable suspension scaffolds, and masons' multi-point
adjustable suspension scaffolds. (1) When two or more scaffolds are
used they shall not be bridged one to another unless they are designed
to be bridged, the bridge connections are articulated, and the hoists
are properly sized.
(2) If bridges are not used, passage may be made from one platform
to another only when the platforms are at the same height and are
abutting.
(3) Scaffolds shall be suspended from metal outriggers, brackets,
wire rope slings, hooks, or means that meet equivalent criteria (e.g.,
strength, durability).
(r) Catenary scaffolds. (1) No more than one platform shall be
placed between consecutive vertical pickups, and no more than two
platforms shall be used on a catenary scaffold.
(2) Platforms supported by wire ropes shall have hook-shaped stops
on each end of the platforms to prevent them from slipping off the wire
ropes. These hooks shall be so placed that they will prevent the
platform from falling if one of the horizontal wire ropes breaks.
(3) Wire ropes shall not be tightened to the extent that the
application of a scaffold load will overstress them.
(4) Wire ropes shall be continuous and without splices between
anchors.
(s) Float (ship) scaffolds. (1) The platform shall be supported by
a minimum of two bearers, each of which shall project a minimum of 6
inches (15.2 cm) beyond the platform on both sides. Each bearer shall
be securely fastened to the platform.
(2) Rope connections shall be such that the platform cannot shift
or slip.
(3) When only two ropes are used with each float:
(i) They shall be arranged so as to provide four ends which are
securely fastened to overhead supports.
(ii) Each supporting rope shall be hitched around one end of the
bearer and pass under the platform to the other end of the bearer where
it is hitched again, leaving sufficient rope at each end for the
supporting ties.
(t) Interior hung scaffolds. (1) Scaffolds shall be suspended only
from the roof structure or other structural member such as ceiling
beams.
(2) Overhead supporting members (roof structure, ceiling beams, or
other structural members) shall be inspected and checked for strength
before the scaffold is erected.
(3) Suspension ropes and cables shall be connected to the overhead
supporting members by shackles, clips, thimbles, or other means that
meet equivalent criteria (e.g., strength, durability).
(u) Needle beam scaffolds. (1) Scaffold support beams shall be
installed on edge.
(2) Ropes or hangers shall be used for supports, except that one
end of a needle beam scaffold may be supported by a permanent
structural member.
(3) The ropes shall be securely attached to the needle beams.
(4) The support connection shall be arranged so as to prevent the
needle beam from rolling or becoming displaced.
(5) Platform units shall be securely attached to the needle beams
by bolts or equivalent means. Cleats and overhang are not considered to
be adequate means of attachment.
(v) Multi-level suspended scaffolds. (1) Scaffolds shall be
equipped with additional independent support lines, equal in number to
the number of points supported, and of equivalent strength to the
suspension ropes, and rigged to support the scaffold in the event the
suspension rope(s) fail.
(2) Independent support lines and suspension ropes shall not be
attached to the same points of anchorage.
(3) Supports for platforms shall be attached directly to the
support stirrup and not to any other platform.
(w) Mobile scaffolds. (1) Scaffolds shall be braced by cross,
horizontal, or
[[Page 46116]]
diagonal braces, or combination thereof, to prevent racking or collapse
of the scaffold and to secure vertical members together laterally so as
to automatically square and align the vertical members. Scaffolds shall
be plumb, level, and squared. All brace connections shall be secured.
(i) Scaffolds constructed of tube and coupler components shall also
comply with the requirements of paragraph (b) of this section;
(ii) Scaffolds constructed of fabricated frame components shall
also comply with the requirements of paragraph (c) of this section.
(2) Scaffold casters and wheels shall be locked with positive wheel
and/or wheel and swivel locks, or equivalent means, to prevent movement
of the scaffold while the scaffold is used in a stationary manner.
(3) Manual force used to move the scaffold shall be applied as
close to the base as practicable, but not more than 5 feet (1.5 m)
above the supporting surface.
(4) Power systems used to propel mobile scaffolds shall be designed
for such use. Forklifts, trucks, similar motor vehicles or add-on
motors shall not be used to propel scaffolds unless the scaffold is
designed for such propulsion systems.
(5) Scaffolds shall be stabilized to prevent tipping during
movement.
(6) Employees shall not be allowed to ride on scaffolds unless the
following conditions exist:
(i) The surface on which the scaffold is being moved is within 3
degrees of level, and free of pits, holes, and obstructions;
(ii) The height to base width ratio of the scaffold during movement
is two to one or less, unless the scaffold is designed and constructed
to meet or exceed nationally recognized stability test requirements
such as those listed in paragraph (x) of Appendix A to this subpart
(ANSI/SIA A92.5 and A92.6);
(iii) Outrigger frames, when used, are installed on both sides of
the scaffold;
(iv) When power systems are used, the propelling force is applied
directly to the wheels, and does not produce a speed in excess of 1
foot per second (.3 mps); and
(v) No employee is on any part of the scaffold which extends
outward beyond the wheels, casters, or other supports.
(7) Platforms shall not extend outward beyond the base supports of
the scaffold unless outrigger frames or equivalent devices are used to
ensure stability.
(8) Where leveling of the scaffold is necessary, screw jacks or
equivalent means shall be used.
(9) Caster stems and wheel stems shall be pinned or otherwise
secured in scaffold legs or adjustment screws.
(10) Before a scaffold is moved, each employee on the scaffold
shall be made aware of the move.
(x) Repair bracket scaffolds. (1) Brackets shall be secured in
place by at least one wire rope at least \1/2\ inch (1.27 cm) in
diameter.
(2) Each bracket shall be attached to the securing wire rope (or
ropes) by a positive locking device capable of preventing the
unintentional detachment of the bracket from the rope, or by equivalent
means.
(3) Each bracket, at the contact point between the supporting
structure and the bottom of the bracket, shall be provided with a shoe
(heel block or foot) capable of preventing the lateral movement of the
bracket.
(4) Platforms shall be secured to the brackets in a manner that
will prevent the separation of the platforms from the brackets and the
movement of the platforms or the brackets on a completed scaffold.
(5) When a wire rope is placed around the structure in order to
provide a safe anchorage for personal fall arrest systems used by
employees erecting or dismantling scaffolds, the wire rope shall meet
the requirements of subpart M of this part, but shall be at least \5/
16\ inch (0.8 cm) in diameter.
(6) Each wire rope used for securing brackets in place or as an
anchorage for personal fall arrest systems shall be protected from
damage due to contact with edges, corners, protrusions, or other
discontinuities of the supporting structure or scaffold components.
(7) Tensioning of each wire rope used for securing brackets in
place or as an anchorage for personal fall arrest systems shall be by
means of a turnbuckle at least 1 inch (2.54 cm) in diameter, or by
equivalent means.
(8) Each turnbuckle shall be connected to the other end of its rope
by use of an eyesplice thimble of a size appropriate to the turnbuckle
to which it is attached.
(9) U-bolt wire rope clips shall not be used on any wire rope used
to secure brackets or to serve as an anchor for personal fall arrest
systems.
(10) The employer shall ensure that materials shall not be dropped
to the outside of the supporting structure.
(11) Scaffold erection shall progress in only one direction around
any structure.
(y) Stilts. Stilts, when used, shall be used in accordance with the
following requirements:
(1) An employee may wear stilts on a scaffold only if it is a large
area scaffold.
(2) When an employee is using stilts on a large area scaffold where
a guardrail system is used to provide fall protection, the guardrail
system shall be increased in height by an amount equal to the height of
the stilts being used by the employee.
(3) Surfaces on which stilts are used shall be flat and free of
pits, holes and obstructions, such as debris, as well as other tripping
and falling hazards.
(4) Stilts shall be properly maintained. Any alteration of the
original equipment shall be approved by the manufacturer.
Sec. 1926.453 Aerial lifts.
(a) General requirements. (1) Unless otherwise provided in this
section, aerial lifts acquired for use on or after January 22, 1973
shall be designed and constructed in conformance with the applicable
requirements of the American National Standards for ``Vehicle Mounted
Elevating and Rotating Work Platforms,'' ANSI A92.2-1969, including
appendix. Aerial lifts acquired before January 22, 1973 which do not
meet the requirements of ANSI A92.2-1969, may not be used after January
1, 1976, unless they shall have been modified so as to conform with the
applicable design and construction requirements of ANSI A92.2-1969.
Aerial lifts include the following types of vehicle-mounted aerial
devices used to elevate personnel to job-sites above ground:
(i) Extensible boom platforms;
(ii) Aerial ladders;
(iii) Articulating boom platforms;
(iv) Vertical towers; and
(v) A combination of any such devices. Aerial equipment may be made
of metal, wood, fiberglass reinforced plastic (FRP), or other material;
may be powered or manually operated; and are deemed to be aerial lifts
whether or not they are capable of rotating about a substantially
vertical axis.
(2) Aerial lifts may be ``field modified'' for uses other than
those intended by the manufacturer provided the modification has been
certified in writing by the manufacturer or by any other equivalent
entity, such as a nationally recognized testing laboratory, to be in
conformity with all applicable provisions of ANSI A92.2-1969 and this
section and to be at least as safe as the equipment was before
modification.
(b) Specific requirements. (1) Ladder trucks and tower trucks.
Aerial ladders shall be secured in the lower traveling position by the
locking device on top of the truck cab, and the manually operated
device at the base of the ladder before the truck is moved for highway
travel.
[[Page 46117]]
(2) Extensible and articulating boom platforms. (i) Lift controls
shall be tested each day prior to use to determine that such controls
are in safe working condition.
(ii) Only authorized persons shall operate an aerial lift.
(iii) Belting off to an adjacent pole, structure, or equipment
while working from an aerial lift shall not be permitted.
(iv) Employees shall always stand firmly on the floor of the
basket, and shall not sit or climb on the edge of the basket or use
planks, ladders, or other devices for a work position.
(v) A body belt shall be worn and a lanyard attached to the boom or
basket when working from an aerial lift.
(vi) Boom and basket load limits specified by the manufacturer
shall not be exceeded.
(vii) The brakes shall be set and when outriggers are used, they
shall be positioned on pads or a solid surface. Wheel chocks shall be
installed before using an aerial lift on an incline, provided they can
be safely installed.
(viii) An aerial lift truck shall not be moved when the boom is
elevated in a working position with men in the basket, except for
equipment which is specifically designed for this type of operation in
accordance with the provisions of paragraphs (a) (1) and (2) of this
section.
(ix) Articulating boom and extensible boom platforms, primarily
designed as personnel carriers, shall have both platform (upper) and
lower controls. Upper controls shall be in or beside the platform
within easy reach of the operator. Lower controls shall provide for
overriding the upper controls. Controls shall be plainly marked as to
their function. Lower level controls shall not be operated unless
permission has been obtained from the employee in the lift, except in
case of emergency.
(x) Climbers shall not be worn while performing work from an aerial
lift.
(xi) The insulated portion of an aerial lift shall not be altered
in any manner that might reduce its insulating value.
(xii) Before moving an aerial lift for travel, the boom(s) shall be
inspected to see that it is properly cradled and outriggers are in
stowed position except as provided in paragraph (b)(2)(viii) of this
section.
(3) Electrical tests. All electrical tests shall conform to the
requirements of ANSI A92.2-1969 section 5. However equivalent d.c.;
voltage tests may be used in lieu of the a.c. voltage specified in
A92.2-1969; d.c. voltage tests which are approved by the equipment
manufacturer or equivalent entity shall be considered an equivalent
test for the purpose of this paragraph (b)(3).
(4) Bursting safety factor. The provisions of the American National
Standards Institute standard ANSI A92.2-1969, section 4.9 Bursting
Safety Factor shall apply to all critical hydraulic and pneumatic
components. Critical components are those in which a failure would
result in a free fall or free rotation of the boom. All noncritical
components shall have a bursting safety factor of at least 2 to 1.
(5) Welding standards. All welding shall conform to the following
standards as applicable:
(i) Standard Qualification Procedure, AWS B3.0-41.
(ii) Recommended Practices for Automotive Welding Design, AWS D8.4-
61.
(iii) Standard Qualification of Welding Procedures and Welders for
Piping and Tubing, AWS D10.9-69.
(iv) Specifications for Welding Highway and Railway Bridges, AWS
D2.0-69.
Note to Sec. 1926.453: Non-mandatory Appendix C to this subpart
lists examples of national consensus standards that are considered
to provide employee protection equivalent to that provided through
the application of ANSI A92.2-1969, where appropriate. This
incorporation by reference was approved by the Director of the
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part
51. Copies may be obtained from the American National Standards
Institute. Copies may be inspected at the Docket Office,
Occupational Safety and Health Administration, U.S. Department of
Labor, 200 Constitution Avenue, NW., room N2634, Washington, DC or
at the Office of the Federal Register, 800 North Capitol Street,
NW., suite 700, Washington, DC.
Sec. 1926.454 Training requirements.
This section supplements and clarifies the requirements of
Sec. 1926.21(b)(2) as these relate to the hazards of work on scaffolds.
(a) The employer shall have each employee who performs work while
on a scaffold trained by a person qualified in the subject matter to
recognize the hazards associated with the type of scaffold being used
and to understand the procedures to control or minimize those hazards.
The training shall include the following areas, as applicable:
(1) The nature of any electrical hazards, fall hazards and falling
object hazards in the work area;
(2) The correct procedures for dealing with electrical hazards and
for erecting, maintaining, and disassembling the fall protection
systems and falling object protection systems being used;
(3) The proper use of the scaffold, and the proper handling of
materials on the scaffold;
(4) The maximum intended load and the load-carrying capacities of
the scaffolds used; and
(5) Any other pertinent requirements of this subpart.
(b) The employer shall have each employee who is involved in
erecting, disassembling, moving, operating, repairing, maintaining, or
inspecting a scaffold trained by a competent person to recognize any
hazards associated with the work in question. The training shall
include the following topics, as applicable:
(1) The nature of scaffold hazards;
(2) The correct procedures for erecting, disassembling, moving,
operating, repairing, inspecting, and maintaining the type of scaffold
in question;
(3) The design criteria, maximum intended load-carrying capacity
and intended use of the scaffold;
(4) Any other pertinent requirements of this subpart.
(c) When the employer has reason to believe that an employee lacks
the skill or understanding needed for safe work involving the erection,
use or dismantling of scaffolds, the employer shall retrain each such
employee so that the requisite proficiency is regained. Retraining is
required in at least the following situations:
(1) Where changes at the worksite present a hazard about which an
employee has not been previously trained; or
(2) Where changes in the types of scaffolds, fall protection,
falling object protection, or other equipment present a hazard about
which an employee has not been previously trained; or
(3) Where inadequacies in an affected employee's work involving
scaffolds indicate that the employee has not retained the requisite
proficiency.
Non-Mandatory Appendices
(Non-mandatory) Appendix A to Subpart L--Scaffold Specifications
This Appendix provides non-mandatory guidelines to assist
employers in complying with the requirements of subpart L of this
part. An employer may use these guidelines and tables as a starting
point for designing scaffold systems. However, the guidelines do not
provide all the information necessary to build a complete system,
and the employer is still responsible for designing and assembling
these components in such a way that the completed system will meet
the requirements of Sec. 1926.451(a). Scaffold components which are
not selected and loaded in accordance with this Appendix, and
components for which no specific guidelines or tables are given in
this Appendix (e.g., joints, ties, components for wood pole
scaffolds more than 60 feet in height, components for heavy-duty
horse
[[Page 46118]]
scaffolds, components made with other materials, and components with
other dimensions, etc.) must be designed and constructed in
accordance with the capacity requirements of Sec. 1926.451(a), and
loaded in accordance with Sec. 1926.451(d)(1).
Index to Appendix A for Subpart L
1. General guidelines and tables.
2. Specific guidelines and tables.
(a) Pole scaffolds:
Single-pole wood pole scaffolds.
Independent wood pole scaffolds.
(b) Tube and coupler scaffolds.
(c) Fabricated frame scaffolds.
(d) Plasterers', decorators' and large area scaffolds.
(e) Bricklayers' square scaffolds.
(f) Horse scaffolds.
(g) Form scaffolds and carpenters' bracket scaffolds.
(h) Roof bracket scaffolds.
(i) Outrigger scaffolds (one level).
(j) Pump jack scaffolds.
(k) Ladder jack scaffolds.
(l) Window jack scaffolds.
(m) Crawling boards (chicken ladders).
(n) Step, platform and trestle ladder scaffolds.
(o) Single-point adjustable suspension scaffolds.
(p) Two-point adjustable suspension scaffolds.
(q)(1) Stonesetters' multi-point adjustable suspension
scaffolds.
(q)(2) Masons' multi-point adjustable suspension scaffolds.
(r) Catenary scaffolds.
(s) Float (ship) scaffolds.
(t) Interior hung scaffolds.
(u) Needle beam scaffolds.
(v) Multi-level suspension scaffolds.
(w) Mobile scaffolds.
(x) Repair bracket scaffolds.
(y) Stilts.
(z) Tank builders' scaffolds.
1. General Guidelines and Tables
(a) The following tables, and the tables in Part 2--Specific
guidelines and tables, assume that all load-carrying timber members
(except planks) of the scaffold are a minimum of 1,500 lb-f/in\2\
(stress grade) construction grade lumber. All dimensions are nominal
sizes as provided in the American Softwood Lumber Standards, dated
January 1970, except that, where rough sizes are noted, only rough
or undressed lumber of the size specified will satisfy minimum
requirements.
(b) Solid sawn wood used as scaffold planks shall be selected
for such use following the grading rules established by a recognized
lumber grading association or by an independent lumber grading
inspection agency. Such planks shall be identified by the grade
stamp of such association or agency. The association or agency and
the grading rules under which the wood is graded shall be certified
by the Board of Review, American Lumber Standard Committee, as set
forth in the American Softwood Lumber Standard of the U.S.
Department of Commerce.
(i) Allowable spans shall be determined in compliance with the
National Design Specification for Wood Construction published by the
National Forest Products Association; paragraph 5 of ANSI A10.8-1988
Scaffolding-Safety Requirements published by the American National
Standards Institute; or for 2 x 10 inch (nominal) or 2 x 9 inch
(rough) solid sawn wood planks, as shown in the following table:
------------------------------------------------------------------------
Maximum Maximum
permissible permissible
Maximum intended nominal load (lb/ span using span using
ft\2\) full thickness nominal
undressed thickness
lumber (ft) lumber (ft)
------------------------------------------------------------------------
25...................................... 10 8
50...................................... 8 6
75...................................... 6
------------------------------------------------------------------------
(ii) The maximum permissible span for 1\1/4\ x 9-inch or wider
wood plank of full thickness with a maximum intended load of 50 lb/
ft.\2\ shall be 4 feet.
(c) Fabricated planks and platforms may be used in lieu of solid
sawn wood planks. Maximum spans for such units shall be as
recommended by the manufacturer based on the maximum intended load
being calculated as follows:
------------------------------------------------------------------------
Rated load capacity Intended load
------------------------------------------------------------------------
Light-duty............... 25 pounds per square foot applied
uniformly over the entire span area.
Medium-duty.............. 50 pounds per square foot applied
uniformly over the entire span area.
Heavy-duty............... 75 pounds per square foot applied
uniformly over the entire span area.
One-person............... 250 pounds placed at the center of
the span (total 250 pounds).
Two-person............... 250 pounds placed 18 inches to the
left and right of the center of the span
(total 500 pounds).
Three-person............. 250 pounds placed at the center of
the span and 250 pounds placed 18 inches to
the left and right of the center of the span
(total 750 pounds).
------------------------------------------------------------------------
Note: Platform units used to make scaffold platforms intended
for light-duty use shall be capable of supporting at least 25 pounds
per square foot applied uniformly over the entire unit-span area, or
a 250-pound point load placed on the unit at the center of the span,
whichever load produces the greater shear force.
(d) Guardrails shall be as follows:
(i) Toprails shall be equivalent in strength to 2 inch by 4 inch
lumber; or
1\1/4\ inch x \1/8\ inch structural angle iron; or
1 inch x .070 inch wall steel tubing; or 1.990 inch x .058
inch wall aluminum tubing.
(ii) Midrails shall be equivalent in strength to 1 inch by 6
inch lumber; or
1\1/4\ inch x 1\1/4\ inch x \1/8\ inch structural angle
iron; or
1 inch x .070 inch wall steel tubing; or
1.990 inch x .058 inch wall aluminum tubing.
(iii) Toeboards shall be equivalent in strength to 1 inch by 4
inch lumber; or
1\1/4\ inch x 1\1/4\ inch structural angle iron; or
1 inch x .070 inch wall steel tubing; or
1.990 inch x .058 inch wall aluminum tubing.
(iv) Posts shall be equivalent in strength to 2 inch by 4 inch
lumber; or
1\1/4\ inch x 1\1/4\ inch x \1/8\ structural angle iron; or
1 inch x .070 inch wall steel tubing; or
1.990 inch x .058 inch wall aluminum tubing.
(v) Distance between posts shall not exceed 8 feet.
(e) Overhead protection shall consist of 2 inch nominal planking
laid tight, or \3/4\-inch plywood.
(f) Screen installed between toeboards and midrails or toprails
shall consist of No. 18 gauge U.S. Standard wire one inch mesh.
2. Specific guidelines and tables.
(a) Pole Scaffolds.
Single Pole Wood Pole Scaffolds
--------------------------------------------------------------------------------------------------------------------------------------------------------
Light duty up to 60 feet Medium duty up to 60 feet Heavy duty up to 60 feet
Light duty up to 20 feet high high high high
--------------------------------------------------------------------------------------------------------------------------------------------------------
Maximum intended load (lbs/ft 25........................... 25.......................... 50.......................... 75
\2\).
Poles or uprights.............. 2 x 4 in..................... 4 x 4 in.................... 4 x 4 in.................... 4 x 6 in.
Maximum pole spacing 6 feet....................... 10 feet..................... 8 feet...................... 6 feet
(longitudinal).
Maximum pole spacing 5 feet....................... 5 feet...................... 5 feet...................... 5 feet
(transverse).
[[Page 46119]]
Runners........................ 1 x 4 in..................... 1\1/4\ x 9 in............... 2 x 10 in................... 2 x 10 in.
Bearers and maximum spacing of
bearers:
3 feet..................... 2 x 4 in..................... 2 x 4 in.................... 2 x 10 in. or 3 x 4 in...... 2 x 10 in. or 3 x 5 in.
5 feet..................... 2 x 6 in. or 3 x 4 in........ 2 x 6 in. or 3 x 4 in. 2 x 10 in. or 3 x 4 in...... 2 x 10 in. or 3 x 5 in.
(rough).
6 feet..................... ............................. ............................ 2 x 10 in. or 3 x 4 in...... 2 x 10 in. or 3 x 5 in.
8 feet..................... ............................. ............................ 2 x 10 in. or 3 x 4 in...... ............................
Planking....................... 1\1/4\ x 9 in................ 2 x 10 in................... 2 x 10 in................... 2 x 10 in.
Maximum vertical spacing of 7 feet....................... 9 feet...................... 7 feet...................... 6 ft. 6 in.
horizontal members.
Bracing horizontal............. 1 x 4 in..................... 1 x 4 in.................... 1 x 6 in. or 1\1/4\ x 4 in.. 2 x 4 in.
Bracing diagonal............... 1 x 4 in..................... 1 x 4 in.................... 1 x 4 in.................... 2 x 4 in.
Tie-ins........................ 1 x 4 in..................... 1 x 4 in.................... 1 x 4 in.................... 1 x 4 in.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: All members except planking are used on edge. All wood
bearers shall be reinforced with \3/16\ x 2 inch steel strip, or the
equivalent, secured to the lower edges for the entire length of the
bearer.
Independent Wood Pole Scaffolds
--------------------------------------------------------------------------------------------------------------------------------------------------------
Light duty up to 60 feet Medium duty up to 60 feet Heavy duty up to 60 feet
Light duty up to 20 feet high high high high
--------------------------------------------------------------------------------------------------------------------------------------------------------
Maximum intended load.......... 25 lbs/ft\2\................. 25 lbs/ft\2\................ 50 lbs/ft\2\................ 75 lbs/ft\2\.
Poles or uprights.............. 2 x 4 in..................... 4 x 4 in.................... 4 x 4 in.................... 4 x 4 in.
Maximum pole spacing 6 feet....................... 10 feet..................... 8 feet...................... 6 feet.
(longitudinal).
Maximum (transverse)........... 6 feet....................... 10 feet..................... 8 feet...................... 8 feet.
Runners........................ 1\1/4\ x 4 in................ 1\1/4\ x 9 in............... 2 x 10 in................... 2 x 10 in.
Bearers and maximum spacing of
bearers:
3 feet..................... 2 x 4 in..................... 2 x 4 in.................... 2 x 10 in................... 2 x 10 in. (rough).
6 feet..................... 2 x 6 in. or 3 x 4 in........ 2 x 10 in. (rough) or 3 x 8 2 x 10 in................... 2 x 10 in. (rough).
in.
8 feet..................... 2 x 6 in. or 3 x 4 in........ 2 x 10 in. (rough) or 3 x 8 2 x 10 in................... ............................
in.
10 feet.................... 2 x 6 in. or 3 x 4 in........ 2 x 10 in.-- (rough) or 3 x ............................ ............................
3 in.
Planking....................... 1\1/4\ x 9 in................ 2 x 10 in................... 2 x 10 in................... 2 x 10 in.
Maximum vertical spacing of 7 feet....................... 7 feet...................... 6 feet...................... 6 feet.
horizontal members.
Bracing horizontal............. 1 x 4 in..................... 1 x 4 in.................... 1 x 6 in. or 1\1/4\ x 4 in.. 2 x 4 in.
Bracing diagonal............... 1 x 4 in..................... 1 x 4 in.................... 1 x 4 in.................... 2 x 4 in.
Tie-ins........................ 1 x 4 in..................... 1 x 4 in.................... 1 x 4 in.................... 1 x 4 in.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: All members except planking are used on edge. All wood
bearers shall be reinforced with \3/16\ x 2 inch steel strip, or the
equivalent, secured to the lower edges for the entire length of the
bearer.
(b) Tube and coupler scaffolds.
Minimum Size of Members
----------------------------------------------------------------------------------------------------------------
Light duty Medium duty Heavy duty
----------------------------------------------------------------------------------------------------------------
Maximum intended load................ 25 lbs/ft\2\........... 50 lbs/ft\2\........... 75 lbs/ft\2\.
Posts, runners and braces............ Nominal 2 in. (1.90 Nominal 2 in. (1.90 Nominal 2 in. (1.90
inches) OD steel tube inches) OD steel tube inches) OD steel tube
or pipe. or pipe. or pipe.
Bearers.............................. Nominal 2 in. (1.90 Nominal 2 in. (1.90 Nominal 2\1/2\ in.
inches). inches). (2.375 in.).
OD steel tube or pipe OD steel tube or pipe OD steel tube or pipe
and a maximum post and a maximum post and a maximum post
spacing of 4 ft. x 10 spacing of 4 ft. x 7 spacing of 6 ft. x 6
ft.. ft. or. ft.
Nominal 2\1/2\ in.
(2.375 in.).
OD steel tube or pipe
and a maximum post
spacing of 6 ft. x 8
ft.*.
Maximum runner spacing vertically.... 6 ft. 6 in............. 6 ft. 6 in............. 6 ft. 6 in.
----------------------------------------------------------------------------------------------------------------
* Bearers shall be installed in the direction of the shorter dimension.
Note: Longitudinal diagonal bracing shall be installed at an
angle of 45 deg. (5 deg.).
[[Page 46120]]
Maximum Number of Planked Levels
------------------------------------------------------------------------
Maximum number of
additional planked levels Maximum
--------------------------- height of
Light Medium Heavy scaffold
duty duty duty (in feet)
------------------------------------------------------------------------
Number of Working Levels:
1........................... 16 11 6 125
2........................... 11 1 0 125
3........................... 6 0 0 125
4........................... 1 0 0 125
------------------------------------------------------------------------
(c) Fabricated frame scaffolds. Because of their prefabricated
nature, no additional guidelines or tables for these scaffolds are
being adopted in this Appendix.
(d) Plasterers', decorators', and large area scaffolds. The
guidelines for pole scaffolds or tube and coupler scaffolds
(Appendix A (a) and (b)) may be applied.
(e) Bricklayers' square scaffolds.
Maximum intended load: 50 lb/ft.\2\*
---------------------------------------------------------------------------
* The squares shall be set not more than 8 feet apart for light
duty scaffolds and not more than 5 feet apart for medium duty
scaffolds.
---------------------------------------------------------------------------
Maximum width: 5 ft.
Maximum height: 5 ft.
Gussets: 1 x 6 in.
Braces: 1 x 8 in.
Legs: 2 x 6 in.
Bearers (horizontal members): 2 x 6 in.
(f) Horse scaffolds.
Maximum intended load (light duty): 25 lb/ft.\2\ **
---------------------------------------------------------------------------
** Horses shall be spaced not more than 8 feet apart for light
duty loads, and not more than 5 feet apart for medium duty loads.
---------------------------------------------------------------------------
Maximum intended load (medium duty): 50 lb/ft.\2\ **
Horizontal members or bearers:
Light duty: 2 x 4 in.
Medium duty: 3 x 4 in.
Legs: 2 x 4 in.
Longitudinal brace between legs: 1 x 6 in.
Gusset brace at top of legs: 1 x 8 in.
Half diagonal braces: 2 x 4 in.
(g) Form scaffolds and carpenters' bracket scaffolds.
(1) Brackets shall consist of a triangular-shaped frame made of
wood with a cross-section not less than 2 inches by 3 inches, or of
1\1/4\ inch x 1\1/4\ inch x \1/8\ inch structural angle iron.
(2) Bolts used to attach brackets to structures shall not be
less than \5/8\ inches in diameter.
(3) Maximum bracket spacing shall be 8 feet on centers.
(4) No more than two employees shall occupy any given 8 feet of
a bracket or form scaffold at any one time. Tools and materials
shall not exceed 75 pounds in addition to the occupancy.
(5) Wooden figure-four scaffolds:
Maximum intended load: 25 lb/ft.\2\
Uprights: 2 x 4 in. or 2 x 6 in.
Bearers (two): 1 x 6 in.
Braces: 1 x 6 in.
Maximum length of bearers (unsupported): 3 ft. 6 in.
(i) Outrigger bearers shall consist of two pieces of 1 x 6
inch lumber nailed on opposite sides of the vertical support.
(ii) Bearers for wood figure-four brackets shall project not
more than 3 feet 6 inches from the outside of the form support, and
shall be braced and secured to prevent tipping or turning. The knee
or angle brace shall intersect the bearer at least 3 feet from the
form at an angle of approximately 45 degrees, and the lower end
shall be nailed to a vertical support.
(6) Metal bracket scaffolds:
Maximum intended load: 25 lb/ft.\2\
Uprights: 2 x 4 inch
Bearers: As designed.
Braces: As designed.
(7) Wood bracket scaffolds:
Maximum intended load: 25 lb/ft.\2\
Uprights: 2 x 4 in or 2 x 6 in
Bearers: 2 x 6 in
Maximum scaffold width: 3 ft 6 in
Braces: 1 x 6 in
(h) Roof bracket scaffolds. No specific guidelines or tables are
given.
(i) Outrigger scaffolds (single level). No specific guidelines
or tables are given.
(j) Pump jack scaffolds. Wood poles shall not exceed 30 feet in
height. Maximum intended load--500 lbs between poles; applied at the
center of the span. Not more than two employees shall be on a pump
jack scaffold at one time between any two supports. When 2 x 4's
are spliced together to make a 4 x 4 inch wood pole, they shall be
spliced with ``10 penny'' common nails no more than 12 inches center
to center, staggered uniformly from the opposite outside edges.
(k) Ladder jack scaffolds. Maximum intended load--25 lb/ft\2\.
However, not more than two employees shall occupy any platform at
any one time. Maximum span between supports shall be 8 feet.
(l) Window jack scaffolds. Not more than one employee shall
occupy a window jack scaffold at any one time.
(m) Crawling boards (chicken ladders). Crawling boards shall be
not less than 10 inches wide and 1 inch thick, with cleats having a
minimum 1 x 1\1/2\ inch cross-sectional area. The cleats shall be
equal in length to the width of the board and spaced at equal
intervals not to exceed 24 inches.
(n) Step, platform, and trestle ladder scaffolds. No additional
guidelines or tables are given.
(o) Single-point adjustable suspension scaffolds. Maximum
intended load--250 lbs. Wood seats for boatswains' chairs shall be
not less than 1 inch thick if made of non-laminated wood, or \5/8\
inches thick if made of marine quality plywood.
(p) Two-point adjustable suspension scaffolds. (1) In addition
to direct connections to buildings (except window cleaners' anchors)
acceptable ways to prevent scaffold sway include angulated roping
and static lines. Angulated roping is a system of platform
suspension in which the upper wire rope sheaves or suspension points
are closer to the plane of the building face than the corresponding
attachment points on the platform, thus causing the platform to
press against the face of the building. Static lines are separate
ropes secured at their top and bottom ends closer to the plane of
the building face than the outermost edge of the platform. By
drawing the static line taut, the platform is drawn against the face
of the building.
(2) On suspension scaffolds designed for a working load of 500
pounds, no more than two employees shall be permitted on the
scaffold at one time. On suspension scaffolds with a working load of
750 pounds, no more than three employees shall be permitted on the
scaffold at one time.
(3) Ladder-type platforms. The side stringer shall be of clear
straight-grained spruce. The rungs shall be of straight-grained oak,
ash, or hickory, at least 1\1/8\ inches in diameter, with \7/8\ inch
tenons mortised into the side stringers at least \7/8\ inch. The
stringers shall be tied together with tie rods not less than \1/4\
inch in diameter, passing through the stringers and riveted up tight
against washers on both ends. The flooring strips shall be spaced
not more than \5/8\ inch apart, except at the side rails where the
space may be 1 inch. Ladder-type platforms shall be constructed in
accordance with the following table:
[[Page 46121]]
Schedule for Ladder-Type Platforms
----------------------------------------------------------------------------------------------------------------
----------------------------------------------------------------------------------------------------------------
Length of Platform............... 12 feet.................. 14 & 16 feet............ 18 & 20 feet.
Side stringers, minimum cross
section (finished sizes):
At ends...................... 1\3/4\ x 2\3/4\ in..... 1\3/4\ x 2\3/4\ in.... 1\3/4\ x 3 in.
At middle.................... 1\3/4\ x 3\3/4\ in..... 1\3/4\ x 3\3/4\ in.... 1\3/4\ x 4 in.
Reinforcing strip (minimum)......
(2)A \1/8\ x \7/8\ inch steel
reinforcing strip shall be
attached to the side or
underside, full length.
Rungs............................
(2)Rungs shall be 1\1/8\ inch
minimum diameter with at least
\7/8\ inch in diameter tenons,
and the maximum spacing shall be
12 inches to center.
Tie rods:
Number (minimum)............. 3........................ 4....................... 4
Diameter (minimum)........... \1/4\ inch............... \1/4\ inch.............. \1/4\ inch
Flooring, minimum finished size.. \1/2\ x 2\3/4\ in...... \1/2\ x 2\3/4\ in..... \1/2\ x 2\3/4\ in.
----------------------------------------------------------------------------------------------------------------
Schedule for Ladder-Type Platforms
------------------------------------------------------------------------
------------------------------------------------------------------------
Length of Platform.......... 22 & 24 ft.......... 28 & 30 ft.
Side stringers, minimum
cross section (finished
sizes):
At ends................. 1\3/4\ x 3 in....... 1\3/4\ x 3\1/2\
in.
At middle............... 1\3/4\ x 4\1/4\ in 1\3/4\ x 5 in.
Reinforcing strip (minimum).
(1)A \1/8\ x \7/8\-inch
steel reinforcing strip
shall be attached to the
side or underside, full
length.
Rungs.......................
(1)Rungs shall be 1\1/8\
inch minimum diameter with
at least \7/8\ inch in
diameter tenons, and the
maximum spacing shall be 12
inches to center. Tie rods.
Number (minimum)........ 5................... 6.
Diameter (minimum)...... \1/4\ in............ \1/4\ in.
Flooring, minimum finished \1/2\ x 2\3/4\ in. \1/2\ x 2\3/4\ in.
size.
------------------------------------------------------------------------
(4) Plank-Type Platforms. Plank-type platforms shall be composed
of not less than nominal 2 x 8 inch unspliced planks, connected
together on the underside with cleats at intervals not exceeding 4
feet, starting 6 inches from each end. A bar or other effective
means shall be securely fastened to the platform at each end to
prevent the platform from slipping off the hanger. The span between
hangers for plank-type platforms shall not exceed 10 feet.
(5) Beam-Type Platforms. Beam platforms shall have side
stringers of lumber not less than 2 x 6 inches set on edge. The
span between hangers shall not exceed 12 feet when beam platforms
are used. The flooring shall be supported on 2 x 6 inch cross
beams, laid flat and set into the upper edge of the stringers with a
snug fit, at intervals of not more than 4 feet, securely nailed to
the cross beams. Floor-boards shall not be spaced more than \1/2\
inch apart.
(q)(1) Multi-point adjustable suspension scaffolds and
stonesetters' multi-point adjustable suspension scaffolds. No
specific guidelines or tables are given for these scaffolds.
(q)(2) Masons' multi-point adjustable suspension scaffolds.
Maximum intended load--50 lb/ft2. Each outrigger beam shall be
at least a standard 7 inch, 15.3 pound steel I-beam, at least 15
feet long. Such beams shall not project more than 6 feet 6 inches
beyond the bearing point. Where the overhang exceeds 6 feet 6
inches, outrigger beams shall be composed of stronger beams or
multiple beams.
(r) Catenary scaffolds. (1) Maximum intended load--500 lbs.
(2) Not more than two employees shall be permitted on the
scaffold at one time.
(3) Maximum capacity of come-along shall be 2,000 lbs.
(4) Vertical pickups shall be spaced not more than 50 feet
apart.
(5) Ropes shall be equivalent in strength to at least \1/2\ inch
(1.3 cm) diameter improved plow steel wire rope.
(s) Float (ship) scaffolds. (1) Maximum intended load--750 lbs.
(2) Platforms shall be made of \3/4\ inch plywood, equivalent in
rating to American Plywood Association Grade B-B, Group I, Exterior.
(3) Bearers shall be made from 2 x 4 inch, or 1 x 10 inch rough
lumber. They shall be free of knots and other flaws.
(4) Ropes shall be equivalent in strength to at least 1 inch
(2.5 cm) diameter first grade manila rope.
(t) Interior hung scaffolds.
Bearers (use on edge): 2 x 10 in.
Maximum intended load: Maximum span
25 lb/ft.\2\: 10 ft.
50 lb/ft.\2\: 10 ft.
75 lb/ft.\2\: 7 ft.
(u) Needle beam scaffolds.
Maximum intended load: 25 lb/ft.\2\
Beams: 4 x 6 in.
Maximum platform span: 8 ft.
Maximum beam span: 10 ft.
(1) Ropes shall be attached to the needle beams by a scaffold
hitch or an eye splice. The loose end of the rope shall be tied by a
bowline knot or by a round turn and a half hitch.
(2) Ropes shall be equivalent in strength to at least 1 inch
(2.5 cm) diameter first grade manila rope.
(v) Multi-level suspension scaffolds. No additional guidelines
or tables are being given for these scaffolds.
(w) Mobile Scaffolds. Stability test as described in the ANSI
A92 series documents, as appropriate for the type of scaffold, can
be used to establish stability for the purpose of
Sec. 1926.452(w)(6).
(x) Repair bracket scaffolds. No additional guidelines or tables
are being given for these scaffolds.
(y) Stilts. No specific guidelines or tables are given.
(z) Tank builder's scaffold.
(1) The maximum distance between brackets to which scaffolding
and guardrail supports are attached shall be no more than 10 feet 6
inches.
(2) Not more than three employees shall occupy a 10 feet 6 inch
span of scaffold planking at any time.
(3) A taut wire or synthetic rope supported on the scaffold
brackets shall be installed at the scaffold plank level between the
innermost edge of the scaffold platform and the curved plate
structure of the tank shell to serve as a safety line in lieu of an
inner guardrail assembly where the space between the scaffold
platform and the tank exceeds 12 inches (30.48 cm). In the event the
open space on either side of the rope exceeds 12 inches (30.48 cm),
a second wire or synthetic rope appropriately placed, or guardrails
in accordance with Sec. 1926.451(e)(4), shall be installed in order
to reduce that open space to less than 12 inches (30.48 cm).
[[Page 46122]]
(4) Scaffold planks of rough full-dimensioned 2-inch (5.1
cm) x 12-inch (30.5 cm) Douglas Fir or Southern Yellow Pine of
Select Structural Grade shall be used. Douglas Fir planks shall have
a fiber stress of at least 1900 lb/in\2\ (130,929 n/cm\2\) and a
modulus of elasticity of at least 1,900,000 lb/in\2\ (130,929,000 n/
cm\2\), while Yellow Pine planks shall have a fiber stress of at
least 2500 lb/in\2\ (172,275 n/cm\2\) and a modulus of elasticity of
at least 2,000,000 lb/in\2\ (137,820,000 n/cm\2\).
(5) Guardrails shall be constructed of a taut wire or synthetic
rope, and shall be supported by angle irons attached to brackets
welded to the steel plates. These guardrails shall comply with
Sec. 1926.451(e)(4). Guardrail supports shall be located at no
greater than 10 feet 6 inch intervals.
Non-Mandatory Appendix B to Subpart L--Criteria for Determining the
Feasibility of Providing Safe Access and Fall Protection for Scaffold
Erectors and Dismantlers
[Reserved]
Non-Mandatory Appendix C to Subpart L--List of National Consensus
Standards
ANSI/SIA A92.2-1990 Vehicle-Mounted Elevating and Rotating Aerial
Devices
ANSI/SIA A92.3-1990 Manually Propelled Elevating Aerial Platforms
ANSI/SIA A92.5-1990 Boom Supported Elevating Work Platforms
ANSI/SIA A92.6-1990 Self-Propelled Elevating Work Platforms
ANSI/SIA A92.7-1990 Airline Ground Support Vehicle-Mounted Vertical
Lift Devices
ANSI/SIA A92.8-1993 Vehicle-Mounted Bridge Inspection and
Maintenance Devices
ANSI/SIA A92.9-1993 Mast-Climbing Work Platforms
Non-Mandatory Appendix D to Subpart L--List of Training Topics for
Scaffold Erectors and Dismantlers
This Appendix D is provided to serve as a guide to assist
employers when evaluating the training needs of employees erecting
or dismantling supported scaffolds.
The Agency believes that employees erecting or dismantling
scaffolds should be trained in the following topics:
General Overview of Scaffolding
regulations and standards
erection/dismantling planning
PPE and proper procedures
fall protection
materials handling
access
working platforms
foundations
guys, ties and braces
Tubular Welded Frame Scaffolds
specific regulations and standards
components
parts inspection
erection/dismantling planning
guys, ties and braces
fall protection
general safety
access and platforms
erection/dismantling procedures
rolling scaffold assembly
putlogs
Tube and Clamp Scaffolds
specific regulations and standards
components
parts inspection
erection/dismantling planning
guys, ties and braces
fall protection
general safety
access and platforms
erection/dismantling procedures
buttresses, cantilevers, & bridges
System Scaffolds
specific regulations and standards
components
parts inspection
erection/dismantling planning
guys, ties and braces
fall protection
general safety
access and platforms
erection/dismantling procedures
buttresses, cantilevers, & bridges
Scaffold erectors and dismantlers should all receive the general
overview, and, in addition, specific training for the type of
supported scaffold being erected or dismantled.
(Non-mandatory) Appendix E to Subpart L--Drawings and Illustrations
This Appendix provides drawings of particular types of scaffolds
and scaffold components, and graphic illustrations of bracing
patterns and tie spacing patterns.
This Appendix is intended to provide visual guidance to assist
the user in complying with the requirements of subpart L, part 1926.
BILLING CODE 4510-26-P
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Sec. 1926.556 [Removed]
2. Section 1926.556 is removed.
[FR Doc. 96-21289 Filed 8-29-96; 8:45 am]
BILLING CODE 4510-26-P
