[Federal Register Volume 61, Number 48 (Monday, March 11, 1996)]
[Rules and Regulations]
[Pages 9764-9846]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-5453]
[[Page 9763]]
_______________________________________________________________________
Part III
Department of Labor
_______________________________________________________________________
Mine Safety and Health Administration
_______________________________________________________________________
30 CFR Part 75
Safety Standards for Underground Coal Mine Ventilation; Final Rule
Federal Register / Vol. 61, No. 48 / Monday, March 11, 1996 / Rules
and Regulations
[[Page 9764]]
DEPARTMENT OF LABOR
Mine Safety and Health Administration
30 CFR Part 75
RIN 1219-AA11
Safety Standards for Underground Coal Mine Ventilation
AGENCY: Mine Safety and Health Administration, (MSHA) Labor.
ACTION: Final rule.
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SUMMARY: This final rule revises the Mine Safety and Health
Administration's (MSHA's) existing safety standards for ventilation of
underground coal mines. After publication of the existing standards,
the U.S. Court of Appeals in the D.C. Circuit stayed the application of
one standard and MSHA stayed two standards. The rule revises these
stayed provisions, revises or clarifies other provisions in the rule
and includes some new provisions. The provisions of the final rule are
expected to decrease the potential for fatalities, particularly
accidents which can result in multiple deaths, and to reduce the risk
of injuries and illnesses in underground coal mines. For the
convenience of the reader, MSHA has published the full text of the
ventilation standards for underground coal mines in this document.
EFFECTIVE DATE: The final rule is effective June 10, 1996.
FOR FURTHER INFORMATION CONTACT: Patricia W. Silvey, Director, Office
of Standards, Regulations and Variances, MSHA, phone 703/ 235-1910; fax
703/235-5551.
SUPPLEMENTARY INFORMATION:
I. Background
The mining of coal underground has historically been recognized as
one of the more hazardous occupations in the world. It is a universally
recognized principle of underground coal mine safety that there must be
proper ventilation of the mine. Indeed, no aspect of safety in
underground coal mining is more fundamental than proper ventilation. A
basic tenet of mining safety states that ventilation must be
sufficient: (1) To dilute, render harmless and carry away the hazardous
components of mine air, such as potentially explosive methane; and (2)
to provide necessary levels of oxygen to the miners' working
environment. Ventilation safety programs are designed around this
philosophy. The history of mining is replete with tragic incidents
where one aspect or another of a necessary ventilation safety
protection was either not in place or not followed, with disastrous
results. Examples include the explosion at the Monogah mine in 1907 in
which 362 miners perished, the worst mining disaster in the history of
the United States. Other more recent examples include the Farmington
disaster in 1968 in which 78 miners died, the Scotia mine in 1976 where
26 died, Grundy No. 17 in 1981 where 13 died, Wilberg in 1984 where 27
died, Pyro in 1989 with 10 deaths and Southmountain in 1992 where 8
miners died. In 1969 and again in 1977, Congress recognized the hazards
of improper ventilation and established a role for the government in
addressing ventilation hazards. MSHA, with the cooperation of labor and
industry, has met with a large measure of success in reducing the
accidents, injuries and fatalities that have resulted from poor
ventilation practices. For example, explosions and fires in a 29 year
period from 1940 to 1968 resulted in the deaths of 491 miners. Since
the passage of the Federal Coal Mine Health and Safety Act of 1969, 178
explosion and fire related deaths have occurred. While MSHA recognizes
that this number is still unacceptable, the significant reduction in
loss of life cannot be ignored. To a great extent, the framework for
this success has been the implementation of effective ventilation
standards.
Preventing recurrence of disasters like those of the past remains
the top priority of MSHA. MSHA believes that a serious commitment by
management, labor, and government is necessary to develop effective,
yet reasonable and practical regulations that protect the safety and
health of our nation's miners. MSHA anticipates that this rulemaking,
which revises portions of the comprehensive ventilation rule published
in 1992 (57 FR 20868, May 15, 1992) and adds new provisions, will bring
the coal mining industry closer to that objective.
The comprehensive 1992 ventilation rulemaking was closely followed
by interested industry and labor groups, who frequently expressed
divergent views on approaches to resolving ventilation issues. Certain
commenters exercised their right to challenge the rule and the U.S.
Court of Appeals for the D.C. Circuit Court stayed one provision
relating to oxygen and carbon dioxide in the bleeder entries. MSHA held
a series of informational meetings around the country during which it
explained the application of the rule. In so doing, MSHA listened to
many questions about the implementation of the rule. MSHA was sensitive
to the views expressed at these meetings and gave serious consideration
to these issues. Some of these comments became the basis for portions
of this rulemaking. Internal discussions of MSHA's experience with the
implementation of the rule led MSHA to include still other issues in
this rulemaking. In fact, MSHA stayed the application of two additional
provisions in response to potential problems pointed out by interested
parties. These stayed provisions relate to actions following the
stoppage of the main mine fan with persons underground and to a
potential fire hazard from the enclosure of compressors in a
noncombustible structure. MSHA addresses these issues in the
rulemaking. Once MSHA decided that it was going to proceed with a
rulemaking to address these issues, it added other provisions to the
package to allow all parties an opportunity to comment where they
expressed the view that they had insufficient opportunity to comment on
the existing rule (The comprehensive rule that was published in the
Federal Register on May 15, 1992). The rule MSHA proposed also included
issues raised by parties in litigation challenging the existing rule.
MSHA anticipates that the final rule should resolve matters included in
the challenge raised by the litigation of the existing rule. Finally,
in an effort to address confusion that seemed to exist with certain
provisions of the existing ventilation rule promulgated in May of 1992,
MSHA either proposed clarifications to the existing rule or discussed
the affected provisions in the preambles to the proposed and final
rules in an effort to clarify them.
The issues in the rulemaking are complex and highly technical.
Comments to the proposal (published on May 19, 1994, 59 FR 26536) and
comments following the public hearings (held in September and October
1994, in Price, Utah, Logan, West Virginia, and Washington,
Pennsylvania) were extensive. One party alone submitted over two
thousand pages of written comments and over 275 exhibits. Not only were
the safety issues involved complex, but in many cases, MSHA's task was
made more difficult by hearing diametrically opposed viewpoints.
Major Improvements in the Final Rule
The final rule provides a number of significant improvements to the
existing ventilation regulations. For example, the final rule provides
for the electronic storage of records. A major portion of the mining
industry has this capability at the present time through computer
technology at the mine site. Electronic
[[Page 9765]]
record retention can reduce the cost of storage and maintenance of
records and provide for ease in access and transfer of information
without reducing the protection afforded miners. Additionally, having
records electronically stored can facilitate trend analysis, allowing
for earlier detection and correction of potential hazards.
The final rule also requires pressure recorders or an option of the
use of a fan monitoring system on main mine fans at all mines. This
represents a major step toward monitoring the mine fans controlling the
ventilation at the mines and helps assure that the miners have
uncontaminated air at all times. The final rule also provides for
methane testing at the face during mining operations. This technology
is especially useful for taking methane tests during extended cut
mining operations. The methane testing evaluates air flow to the face
to determine that methane is sufficiently diluted, rendered harmless,
and carried away so as to reduce or eliminate the hazards associated
with methane liberated during mining operations.
Other improvements in the rule include revisions to the three
stayed provisions in the existing rule. Air quality levels for oxygen
and carbon dioxide in bleeders are established to protect mine
examiners who are required to travel to determine if the bleeders are
functioning properly. A second stayed provision is revised to limit the
use of transportation equipment during the withdrawal of miners after
an unintentional fan stoppage. This revision to the existing rule
reduces the likelihood of an ignition from methane that can accumulate
during the fan stoppage. The third stayed provision is revised to allow
the option of attending rather than housing compressors in a
noncombustible enclosure. The hazards associated with the operation of
compressors in underground mines were demonstrated at the Wilberg mine
disaster, where 27 people lost their lives as a result of a compressor
fire.
This final rule provides for an alert and alarm device to be
located outside of noncombustible structures housing electrical
installations. The alert and alarm assures that miners are made aware
of a problem in time to extinguish a fire or safely evacuate an area or
the mine as necessary for safety. Another change to the existing rule
involves miners or their representatives in the mine ventilation plan
approval process before the plan is submitted for approval. This
provides for the opportunity for input from those having first hand
knowledge in the particular mining conditions and practices that impact
the plan approval.
Other safety enhancements from the existing rule include: requiring
the use of extendable probes to conduct methane tests at deep cuts;
requiring on-shift examinations on other than coal producing shifts;
and accepting a performance test to determine minimum dimensions at
certain locations in escapeways.
Finally, the final rule clarifies existing regulations that were
considered vague by some parties or were misunderstood. For example,
the final rule provides that certified pumpers can conduct their own
examination rather than requiring the examination to be conducted
during the preshift segment of the mining operation.
To serve the interests of the mining community, MSHA has
republished the full text of subpart D of 30 CFR part 75 as it will
read upon promulgation of this rule.
II. Discussion of the Final Rule
A. General Discussion
In developing the final rule, MSHA has made every effort to address
the comments received during the rulemaking, and to develop practical
requirements for real safety problems. Both the costs and the benefits
of each standard were also considered. In addition, each standard, as
well as revisions and deletions, was carefully considered against the
statutory requirement that nothing in the final rule shall reduce the
protection afforded miners by an existing mandatory health or safety
standard. Where appropriate, MSHA has provided for a phase in period to
allow mine operators time to effectively plan and implement the
necessary changes.
MSHA carefully analyzed the comments received and responded in many
instances by revising the proposed requirements. For example, unlike
the proposal, the final rule does not require the second level
countersigning of records; allows the use of nonpermissible equipment
when conducting an examination upon restart of a fan following
unintentional fan stoppages, and requires pressure recording devices or
an option of the use of a fan monitoring system to be used on all main
mine fans.
Several commenters strongly urged MSHA to proceed in this
rulemaking on the issue of using air coursed through the belt entries
(``belt air'') to ventilate the working face. MSHA has completed its
consideration of the Report of the Secretary's Advisory Committee
Report on Belt Air and has placed the issue of using belt air to
ventilate the working face on the rulemaking agenda for development of
a proposed rule. Thus, ``belt air'' is not addressed in this
rulemaking.
MSHA has also received comments and recommendations on a number of
other issues that are outside the scope of this rulemaking. For
example, much of the extensive testimony directed toward the use of
atmospheric monitoring systems was beyond the issues dealt with in this
rulemaking. Also, recommendations for the use of transparent or
translucent material for check curtains exceed the scope of this
rulemaking. The final rule, therefore, does not include these
recommendations.
Commenters to the proposal frequently included a discussion of
various accident reports, most written by MSHA. In addition, there were
discussions of other documents related to specific incidents or mines,
such as MSHA Internal Review Reports or specific mine plans. In some
cases, the documents were submitted for inclusion in the record. In
other cases, the documents were merely referenced.
MSHA is independently aware of the extensive history of ventilation
related explosions, and has considered this information. Where
appropriate, this information is discussed in the section-by-section
analysis in the preamble of this rule. MSHA is aware that accidents can
result from or be contributed to by the violation of one or more of the
existing standards. In that context, MSHA has found that the solution
is not necessarily to promulgate another standard. (The offender may be
as likely to ignore it as well.) Instead, for demonstrated
noncompliance with existing standards, the solution is often found in
increased emphasis, training, or enforcement, rather than in the
promulgation of additional rules.
Several sections of the final rule deal with requirements for
sections and areas where mechanized mining equipment is being installed
or removed. These provisions, which were included in the existing
standard published in May 1992, were reproposed without change for the
purpose of receiving additional comments from all interested parties.
One commenter cited the William Station mine explosion as evidence of
the need for these requirements. Other commenters reiterated an earlier
objection that the standards were procedurally flawed. MSHA does not
agree that these provisions are procedurally flawed and notes that each
of these standards was reproposed and not simply restated as part of
this rulemaking. Comments relative to the
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technical merits of an individual standard are addressed in the
section-by-section portion of this preamble.
Recordkeeping Requirements in the Final Rule
The final rule revises the recordkeeping requirements for several
standards. The standards affected are Sec. 75.310, Installation of main
mine fans; Sec. 75.312, Main mine fan examinations and records;
Sec. 75.342, Methane monitors; Sec. 75.360, Preshift examination;
Sec. 75.362, On-shift examination; Sec. 75.363, Hazardous conditions;
posting, correcting and recording; Sec. 75.364, Weekly examinations;
and Sec. 75.370, Mine ventilation plan; contents.
Generally, the final rule requires examiners to record the results
of methane tests as a percent of methane detected; records must be made
in a book that is secure and not susceptible to alteration, or
electronically in such a manner as to be secure and not susceptible to
alteration; and records must be countersigned by the mine foreman by
the end of the mine foreman's next regularly scheduled working shift.
These rules are intended to assure that examination results are
maintained and made available, and that the appropriate level of mine
management is made aware of conditions or problems requiring attention.
The revisions also help assure the integrity of records and enable mine
management to review the quality of the examinations. MSHA intends the
term ``secure and not susceptible to alteration'' when applied to
electronic storage to mean that the stored record cannot be modified.
One example of acceptable storage would be a ``write once, read many''
drive.
Numerous comments were received both supporting and opposing the
proposed recordkeeping requirements. MSHA reviewed and fully considered
each of these comments. The proposal would have required that records
be kept in either state-approved books or in bound books with
sequential machine-numbered pages. Commenters argued that under the
existing rule records may be falsified or altered. Commenters also
stated that accident investigations have demonstrated the need for
improved records. Other commenters asserted that the proposed
requirement for bound books with sequential machine-numbered pages adds
an economic burden for the majority of compliant operators and another
way should be found, ``to foil the very few who are recalcitrant.''
Other commenters stated that since all records currently include dates
and times, machine-numbered pages are unnecessary.
Some record books that are currently in use and acceptable under
the existing standards are vulnerable to misuse or manipulation. For
example, under the existing rule, records could be kept in a spiral
notebook or even a loose leaf binder. The final rule addresses this
issue by requiring that records be made in books that are secure and
not susceptible to alteration. Examples of books that are considered by
MSHA to be secure and not susceptible to alteration include, but are
not limited to, record books that are currently approved by state mine
safety agencies, and permanently bound books. Examples of books that
would not be considered books that are secure and not susceptible to
alteration include loose leaf binders and spiral note books.
Several commenters advocated the use of computers for the storage
and retrieval of records. In support of this approach, the commenters
cited computer records as being highly accurate, requiring less storage
space and facilitating data retrieval. Other commenters expressed
concern for the security of records stored electronically, and offered
examples of breaches of security in record systems at banks and
national security installations as evidence to support this concern.
Electronic storage of information and assessing it through
computers is more and more a common business practice generally and in
the mining industry. Recognizing this trend, the final rule permits the
use of electronically stored records provided they are secure and not
susceptible to alteration, are able to capture the information and
signatures required, and are accessible to the representative of the
miners and the representatives of the Secretary. Based on the
rulemaking record, MSHA believes that electronic records meeting these
criteria are practical and as reliable as traditional records.
In the preamble to the proposal, MSHA expressed its intent to
require a hard copy printout of the information stored electronically
to be available within 1 hour of a request, and to require backing up
of the information within 24 hours. Commenters objected to making the
records available within 1 hour as being too stringent and
unnecessarily requiring a person to be on duty at all times. MSHA
agrees that the requirement would be overly burdensome and has not
included it in the final rule. Similarly, MSHA has not included a
specific requirement for backing up the computer data. The final rule
requires that the records be secure. This encompasses backing up the
data as appropriate to the conditions and electronic storage system
used at the mine. Upon reconsideration, MSHA has concluded that an
additional specific requirement would be an unnecessary burden and has
not included it in the rule.
A variety of comments were received regarding the countersigning of
certain records by the mine foreman, and the time frame permitted for
countersigning. The final rule adopts the proposal that the mine
foreman must countersign the record by the end of the mine foreman's
next regularly scheduled working shift. The mine foreman is the person
most responsible for the day-to-day operation of the mine. It is
essential for the health and safety of the miners that the mine foreman
be fully aware of the information contained in examination reports so
as to be able to allocate resources to correct safety problems as they
develop. Allowing until the end of the mine foreman's next regularly
scheduled working shift to countersign the reports assures that the
mine foreman is aware of the results of the examination in sufficient
time to initiate corrective actions. In response to commenters, the
final rule allows a mine official equivalent to a mine foreman to
countersign the records.
Some commenters suggested that the time for countersigning is
unnecessarily long, and that the final rule should restore a previous
requirement that countersigning be completed ``promptly.'' The term
``promptly'' involves a level of ambiguity that is eliminated by
specifying the time for countersigning records. The record does not
show that the time set by the final rule would expose miners to safety
or health risks. Also, hazardous conditions are required to be
corrected immediately.
Commenters suggested that the term ``mine foreman'' be replaced by
a ``certified person responsible for ventilation of the mine or his
designee.'' Another commenter suggested that the record could be
countersigned by the mine foreman or any other mine official
responsible for the day-to-day operation of the mine. Commenters stated
that some operations no longer use the terms ``mine foreman'', ``mine
manager,'' or ``superintendent.'' To provide for alternative management
titles, the final rule incorporates the phrase ``or equivalent mine
official.''
Numerous comments were received regarding the requirement of the
proposal for second level countersigning by the mine superintendent,
mine manager, or other mine official to whom the mine foreman is
directly accountable within 2 scheduled
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production days thereafter. Commenters objecting to the proposal stated
that higher level management should be able to delegate responsibility,
noting that often this level of official has more than one mine to
oversee and may not necessarily be available within the proposed two
days. One commenter suggested allowing three days for second level
countersigning in order to recognize that such an official often has
numerous obligations and to allow for normal absences. Other commenters
simply recommended that the second level countersigning be deleted.
Another commenter stated that some states hold the mine foreman
legally responsible, that the mine foreman should correct hazardous
conditions immediately and withdraw miners as appropriate, and that the
second level countersigning would add no measure of safety. One
commenter noted that in many cases the mine manager or superintendent
is not a certified individual and long periods may elapse during which
this person does not go underground. In these instances, the person
countersigning would have little or no understanding or first hand
knowledge of the conditions in the mine. Commenters stated that
countersigning by the mine foreman is adequate notification to the
operator of any deficiency and that the mine foreman has the necessary
resources and responsibility to correct any situation noted in the
records.
Other commenters supported the proposal noting that second level
countersigning would provide an additional level of accountability.
These commenters also suggested that in the event of a major accident,
the second level countersigning requirement would be important in fully
assessing the contributing causes.
MSHA has determined that countersigning by the mine foreman or
equivalent mine official, as specified in the final rule, provides the
means necessary to detect and correct developing hazards in a mine.
Countersigning by the mine foreman assures the necessary notification
to an official with the knowledge of the day-to-day operation of the
mine having the authority to maintain the mine in a safe operating
condition. Agency experience has demonstrated that higher level mine
officials commonly lack hands-on involvement or in-depth knowledge of
the specific conditions underground or how the highly detailed
ventilation rules impact upon those conditions. Therefore,
countersigning by a mine official at a higher level does not assure any
additional level of safety and imposes an unnecessary burden.
B. Section-by-Section Discussion
The following section-by-section portion of the preamble discusses
each provision affected. The text of the final rule is included at the
end of the document.
Section 75.301 Definitions
The final rule revises the definition of return air to permit
operators to designate certain air courses as return air courses for
the purpose of ventilating structures, areas or installations that are
required to be ventilated to return air courses and for ventilating
seals when the air in the air course will not be used to ventilate
working places. Thus, an operator wishing to split air off of an intake
for the purpose of ventilating shops, electrical installations, or for
other purposes, could designate the air course into which the split is
directed as a return provided the air in the air course would not be
used to ventilate working places or other locations, structures,
installations or areas required to be ventilated with intake air.
Commenters generally agreed with the change. However, one commenter
expressed the concern that air currents ventilating electrical
installations could be coursed to the conveyor belt entry before being
coursed to a redesignated return air course, and thus not vented
directly to a return. The commenter expressed the opinion that because
the air is not vented directly to a return under this scenario, the
rule would not permit this practice. MSHA does not agree with the
commenter's interpretation and the final rule, consistent with
Sec. 75.340, permits this practice.
MSHA does not anticipate that operators will need to redesignate
air courses on a routine basis. When questions arise as to the need to
redesignate an intake as a return, the operator should contact the
local MSHA office. In order that all interested persons are made aware
when an air course is redesignated, the final rule requires in
Sec. 75.372, Mine ventilation map, that such redesignated air courses
be shown on the mine's ventilation map.
Section 75.310 Installation of Main Mine Fans
The main mine fans serve a vital role in providing ventilation to
prevent methane accumulations and possible explosions as well as
providing miners with a healthful working environment. Section 75.310
is primarily directed at protecting the main mine fans from fires and
damage in the event of an underground explosion so that necessary
ventilation can be maintained. Monitoring of the fans to assure that
they are operating properly is an element of this protection. The final
rule for Sec. 75.310 revises paragraphs (a) and (c) of the existing
rule. The revisions address: (1) automatic signals for fan stoppage,
(2) pressure recording devices, and (3) main mine fan monitoring
systems.
Paragraph (a)(3) of Sec. 75.310, like the proposal, requires each
main mine fan to be equipped with an automatic device that gives a
signal at the mine when the fan either slows or stops. The existing
rule does not specify where the signal is to be given. Commenters
supported the proposal stating that a signal alarming at a location
away from the mine site would rely on overland communication lines to
transmit the signal, with the person receiving the signal then
notifying the mine. These overland communication lines are subject to
weather and other potential sources of damage, which could result in a
disruption of the communication. Other commenters objected to the
proposal, however, stating that the ability of a mine operator to
consolidate monitoring of several mines at one single location is a
very efficient and cost-effective practice and should not be
arbitrarily prohibited. Further, they stated that there would be
absolutely no delay in contacting the miners from this central location
should a fan malfunction occur. For clarity and for increased safety,
the final rule requires that the signal be given at the mine. MSHA
believes that in the case of a fan stoppage, this will assure more
timely notice to miners, and hence, a more effective safety response.
The requirement that the signal be given at a surface location at the
mine does not preclude the signal from also being given elsewhere, such
as at a central office, as long as it is given at the mine.
Paragraph (a)(3) of Sec. 75.310 requires that a responsible person,
designated by the operator, shall always be at a surface location at
the mine where the signal can be seen or heard while anyone is
underground. In addition, the responsible person must be provided with
two-way communication with working sections and with other established
locations where persons are normally assigned to work. Commenters
supported the proposal stating that the changes provide clarification
and specificity. Other commenters agreed with the proposed concept of
two-way communication but felt that the wording, ``established
locations where persons are normally assigned to work'' is ambiguous
and subject to misinterpretation. Some commenters
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objected to the proposed requirement stating that (1) it is redundant
of Sec. 75.1600 Communications; (2) properly the subject of a separate
rulemaking under Sec. 75.1600 or; (3) it is vague, ambiguous, or
subjective. Section 75.1600 only requires two-way communication between
the surface and working sections and does not identify that this
communication must be provided to a location where a person can see or
hear the fan alarm signal. Commenters suggested that the requirement be
revised to more specifically quantify locations where persons are
normally assigned to work. MSHA recognizes that, as proposed, the
standard might result in misinterpretation and the final rule has been
reworded to read, ``* * * two-way communication with working sections
and work stations where person(s) are routinely assigned to work for
the majority of a shift.''
Some, but not all, outby areas where two-way communication would be
required by the final rule include; shops, attended belt transfer
points, attended rail car loading points, and attended underground coal
storage bins and hoppers. It is not intended that this communications
capability be provided in areas where secondary roof support is being
installed or where rock dust is being applied, or at unattended
underground pumps, or in areas such as return air courses, bleeder
entries and conveyor belt haulageways other than at belt transfer
points. The requirement that two-way communication be provided to work
stations where persons are routinely assigned to work for the majority
of a shift is intended to help assure that these persons receive prompt
notification of fan stoppages. Because these work stations are off the
working section, a lack of communication capabilities could result in
delays in notification and therefore delays in egress from the mine.
Paragraph (a)(4) of the existing rule requires that main mine fans
be equipped with a pressure recording device or with a main mine fan
monitoring system but exempts from this requirement mines permitted to
shut down main mine fans under Sec. 75.311.
The final rule eliminates this exemption and requires that all main
mine fans be equipped with a pressure recording device or a main mine
fan monitoring device. For mines not currently required to have such a
device, MSHA has provided for a 1 year phase in period to allow mine
operators time to effectively plan and implement the necessary changes.
One commenter suggested that all main mine fans at all mines be
required to operate continually and further suggested that all main
mine fans be equipped with pressure recording devices and main mine fan
monitoring systems. In support of this suggestion, the commenter stated
that continuous fan pressure recording devices would have a positive
impact on safety at these operations. Such devices will provide
necessary information to operators and miners at operations affected by
this change. MSHA has not included one commenter's suggestion that main
mine fan monitoring systems be required for all main mine fans. While
MSHA supports and encourages the use of this advanced technology the
Agency does not believe that it is appropriate to mandate it for all
mines because daily fan examinations coupled with pressure recording
devices have proved to be adequate over the years. Also, MSHA does not
adopt a suggestion that main mine fans at all mines be required to
operate continuously.
Paragraph (a)(4) of the final rule requires that when a pressure
monitoring device is used in lieu of a pressure recording device, it
must produce a continuous graph or chart of the fan pressure. A hard
copy of the continuous graph or chart must be printed at regular
intervals of not more than 7 days. This provision permits the use of
relatively recent advances in technology for monitoring main mine fan
pressure provided a continuous record of the fan pressure is provided.
In the proposal, MSHA specifically solicited comments as to an
appropriate polling frequency that would provide a record that is
substantially continuous. In response to this request, one commenter
proposed that a polling frequency of two seconds is necessary to take
full advantage of available technology. This commenter stated that
continuously means constant or unbroken and that a continuous record
should require a polling frequency of not greater than 2 seconds.
Another commenter, an instrument manufacturer, suggested that a one
minute sampling interval is definitely feasible. Main mine fan
monitoring, when used, is often part of a more comprehensive mine-wide
atmospheric monitoring system (AMS), and to require that the fan be
polled every two seconds could delay the polling of other important
sensors. Additionally, because these pressure monitoring devices are
intended to be used in lieu of the traditional circular pressure
recorder they must provide a substantially equivalent record.
Experience by MSHA engineers following mine explosions and during more
routine ventilation survey work has shown that the accuracy to which a
7-day, circular recording chart of the type normally used can be read
is on the order of several minutes. MSHA would expect that the polling
frequency for a pressure recording device used in lieu of a pressure
recorder would be no more than one (1) minute.
MSHA received a number of comments in response to the proposed
requirement in paragraph (a)(4) that when a pressure recording device
other than a circular pressure recorder is used, a hard copy of the
continuous graph or chart be generated at not more than 7-day
intervals. Comments ranged from requiring daily printouts to not
requiring any printout except when requested by an Authorized
Representative of the Secretary. In response to these comments, the
final rule retains the requirement for a hard copy of the continuous
graph or chart be generated at not more than 7-day intervals. In light
of MSHA's stated position to permit records of examinations to be
stored electronically, the final rule permits the record of main mine
fan pressure to be stored electronically provided the record is secure
and not susceptible to alteration.
Paragraph (c) of Sec. 75.310 specifies requirements for main mine
fan monitoring systems if used under Sec. 75.312. Commenters suggested
that the requirements were repetitive, confusing, and would discourage
mine operators from using monitoring systems which could provide more
protection. MSHA believes that the requirements in paragraph (c) are
necessary to effectively monitor a fan, particularly when these systems
are used in lieu of daily fan examinations.
Paragraph (c)(3) of Sec. 75.310 of the proposal would have required
that main mine fan monitoring systems provide, on demand, a printout of
the monitored parameters, including the mine ventilating pressure.
Several commenters objected to the requirement that a printout be
provided ``on demand.'' As interpreted by these commenters, this
standard would require that the operator provide a printout at any time
it is requested. As explained in the preamble to the proposal, ``* * *
the monitoring system would be required to have the capability of
providing (emphasis added), on demand, a printout of the information
being monitored. This capability is intended to facilitate the review
of the information by mine management required in Sec. 75.312(b).'' The
commenters misinterpreted the purpose for the standard. MSHA
recognizes,
[[Page 9769]]
however, the merits of being able to obtain a printout within a
reasonable period of time. Therefore, the final rule requires that a
main mine fan monitoring system used to satisfy the requirements of
Sec. 75.312 provide a printout of the monitored parameters, including
the mine ventilating pressure, within a reasonable period, not to
exceed the end of the next scheduled shift during which miners are
underground.
Paragraph (c)(5) of Sec. 75.310 requires that two-way communication
be provided between a surface location at the mine where the signals
from the fan monitoring system can be seen or heard and working
sections and other established locations where persons are normally
assigned to work for the majority of the shift. Except for minor
editorial changes, this requirement is the same as the proposal.
Comments on this proposal were the same as comments on proposed
paragraph (a)(3). Several commenters supported the proposal stating
that the changes provide clarification and specificity. Other
commenters agreed with the proposed concept of two-way communication
but felt that the wording, ``established locations where persons are
normally assigned to work'' is ambiguous and subject to
misinterpretation. Some commenters objected to the proposed requirement
stating that (1) it is redundant of Sec. 75.1600 Communications; (2)
properly the subject of a separate rulemaking under Sec. 75.1600 or;
(3) it is vague, ambiguous, or subjective. Section 75.1600 only
requires two-way communication between the surface and working sections
and does not identify that this communication must be provided to a
location where a person can see or hear the fan alarm signal.
Commenters suggested that the requirement be revised to more
specifically quantify locations where persons are normally assigned to
work. MSHA recognizes that, as proposed, the standard might result in
misinterpretation and the final rule has reworded the proposal to read,
``* * * two-way communication with working sections and work stations
where person(s) are routinely assigned to work for the majority of a
shift.''
Some, but not all, outby areas where two-way communication would be
required by the final rule include; shops, attended belt transfer
points, attended rail car loading points, and attended underground coal
storage bins and hoppers. It is not intended that this communications
capability be provided in areas where secondary roof support is being
installed or where rock dust is being applied, or at unattended
underground pumps, or in areas such as return air courses, bleeder
entries and conveyor belt haulageways other than at belt transfer
points. The requirement that two-way communication be provided to work
stations where persons are routinely assigned to work for the majority
of a shift is intended to help assure that these persons receive prompt
notification of fan stoppages or other problems with the fan that might
require withdrawal of miners. Because these work stations are off the
working section, a lack of communication capabilities could result in
delays in notification and therefore delays in egress from the mine.
Section 75.311 Main Mine Fan Operation
The main mine fan provides the pressure that causes air to move
through the mine to dilute and carry away explosive and toxic gases,
dusts and fumes. As such it is the most important part of the
ventilation system. Section 75.311 requires fans to be continuously
operated to provide constant ventilation to underground areas and
specifies precautions for planned fan stoppages. It also addresses the
repair of main mine fans, monitoring of fan signal devices on the
surface, and protection against fires around fans and intake air
openings.
The final rule revises paragraph (d) of Sec. 75.311, which
addresses the notification of mine officials of any unusual variance in
mine ventilation pressure and requires the prompt repair of electrical
or mechanical deficiencies. The final rule requires immediate
notification and the prompt institution of corrective action or
repairs.
Commenters suggested deletion of the word ``unusual'' maintaining
that this term makes the requirement vague and subject to different
interpretations. These commenters suggested substituting the phrase,
``that could materially affect the safety and health of persons in the
mine'' to describe the type of pressure variance that would require
action. In making this recommendation, the commenters cited similar
language in existing Sec. 75.324(a)(1) that, according to the
commenters, is understood throughout the coal mining community. Section
75.324(a)(1) concerns alterations of the main ventilation air current
or any split of the main air current. The final rule does not adopt
this recommendation. Minor fluctuations in fan operating pressure are
normal; however, unusual changes can be indications of changes in fan
operation or changes underground, such as roof falls or loss of
ventilation controls, that require prompt attention and corrective
action. In addition, MSHA has 25 years of experience with the phrase
``unusual variances in mine ventilation pressure'' and is unaware of
significant difficulties with this terminology.
Commenters questioned what constitutes an ``electrical or
mechanical deficiency'' for the purposes of Sec. 75.311. The purpose of
the standard is to assure that a problem with main mine fans is
corrected promptly and that the proper persons are notified that the
problem exists. The types of electrical or mechanical deficiencies
requiring action under paragraph (d) are those that can interfere with
mine ventilation. In addition, MSHA has 25 years of experience with the
phrase ``electrical and mechanical deficiencies'' and is, again,
unaware of any significant difficulties with the use of this
terminology during this time frame.
Commenters also addressed the proposal that the ``mine
superintendent, assistant mine superintendent, or mine foreman'' be
notified immediately when an unusual variance in mine ventilation
pressure is observed, or when an electrical or mechanical deficiency in
a main mine fan is detected. The final rule does not retain the mine
superintendent or the assistant mine superintendent as mine officials
to be notified. Commenters stated that this provision provides a
measure of safety to the miners by requiring that specific mine
managers be notified of possible main mine fan problems, while the
existing standard specifies that such a situation must be investigated.
Other commenters, however, suggested that the persons identified for
notification under the proposal may not be the most qualified to handle
the problem. They also indicated that the notification requirement
could unnecessarily delay appropriate action by other responsible
persons. The commenters further stated that the mine superintendent or
assistant mine superintendent may not be at the mine and that a
certified person would be in charge who should be permitted to take the
appropriate action. The proposed requirement that certain mine managers
be notified immediately was not intended to require that these
individuals personally take the necessary actions to respond to the
problem with the main mine fan. Neither was it intended that they be
notified of such a problem, to the exclusion of all others. The
objective of the rule is to assure that the appropriate actions are
taken as soon as possible. Additionally, notification of specified mine
officials is intended to assure that those persons who are responsible
for the mine are aware of the problem. The
[[Page 9770]]
final rule, therefore, retains the requirement that certain mine
managers be notified of any unusual variance in the mine ventilation
pressure or if an electrical or mechanical deficiency of a main mine
fan is detected.
The final rule does, however, delete reference to notification of
the mine superintendent or assistant mine superintendent. As discussed
in relation to the countersigning of records, the mine superintendent
is quite often not a certified person and is only periodically present
at the mine. In addition, consistent with other sections of the final
rule and recognizing that the term mine foreman is not used at some
mines, the final rule requires that if an unusual variance in the mine
ventilation pressure is observed, or if an electrical or mechanical
deficiency of a main mine fan is detected, the mine foreman or
equivalent mine official, or in the absence of the mine foreman or
equivalent mine official, a designated certified person acting for the
mine foreman or equivalent mine official shall be notified immediately.
As with the proposal, the final rule requires that appropriate action
or repairs shall be instituted promptly. It is not intended that the
appropriate action or repairs be delayed until the mine foreman or
equivalent mine official is notified.
During a series of informational meetings held by MSHA following
publication of the existing rule, questions arose concerning the
operation of back-up fans. For informational purposes, the preamble to
the proposal included a detailed discussion of questions about the
operation of back-up fans under the ventilation regulations and
solicited comments. MSHA did not propose any rule changes, nor does the
final rule contain specific provisions for back-up fans. When a back-up
fan operates in place of the main mine fan, the back-up fan is
considered to be a main mine fan and all subpart D requirements for
main mine fans are applicable.
Section 75.312 Main Mine Fan Examinations and Records
Proper operation of main mine fans is critical to mine ventilation
and the prevention of methane accumulations and possibly methane
explosions. Recognizing the importance of the main mine fan,
Sec. 75.312 requires that each main mine fan be examined at least once
each day that the fan operates unless the fan is continuously monitored
with a main mine fan monitoring system. Through daily examinations or
continuous monitoring of critical parameters, the operator can
determine if problems with the fan are developing and correct these
problems before ventilation is affected.
The final rule removes existing paragraph (g)(2), revises existing
paragraphs (a), (b)(1), (c), (d), (g)(1) and (h), redesignates existing
paragraph (f) as (f)(1), and adds new paragraphs (f)(2) and (g)(2).
Paragraph (a) of the final rule, like the existing rule, requires daily
examination of main mine fans unless a fan monitoring system is used.
In addition, paragraph (a) specifies that an examination of the main
mine fan is not required on days when no person goes underground. An
examination of the fan, however, is required prior to anyone entering
the mine. The purpose of this examination, as stated in paragraph (a),
is to assure the electrical and mechanical reliability of the fan.
When a fan monitoring system is used, the final rule requires a
daily review of the data from the monitoring system to be made, except
on days when no person goes underground. A review of the data from the
monitoring system must be completed, however, prior to anyone entering
the mine.
Fan examinations or review of fan monitoring system data are
required to be performed by a trained person designated by the
operator.
Commenters questioned the use of the term ``assure'' in paragraph
(a) when referring to the electrical and mechanical reliability of main
mine fans. MSHA uses the term ``assure'' in this context as defined in
Webster's Third New International Dictionary, Unabridged, 1993 edition,
to mean, ``to make safe, to give confidence to.'' The sense of this
definition is consistent with the intended purpose of the examination.
The term does not mean to ``guarantee'' safety, as suggested by one
commenter.
Commenters suggested that the final rule require the examination of
main mine fans for proper operation be conducted by an individual
trained as part of the mine operator's training plan required by MSHA's
comprehensive training regulation in part 48 of 30 CFR. Other
commenters understood the proposal to require training of fan examiners
under part 48, and objected to such a requirement. These commenters
suggested that the person conducting the fan examination be one who has
received training through experience or has been trained by an
experienced person, or by the fan manufacturer. The final rule does not
require fan examiners to be trained as part of the operator's part 48
training plan. Instead, the final rule specifies that fan examiners
must be trained sufficiently to have the skill and knowledge to
ascertain whether the fan is in proper working order, mechanically and
electrically.
Paragraph (a) requires a daily physical examination of the main
mine fan, unless a fan monitoring system is used. If a fan monitoring
system is used, paragraph (b) requires a weekly physical examination of
the main mine fan, a weekly test of the monitoring system, and a daily
review of the main mine fan monitoring data. Commenters suggested that
even if a main mine fan is equipped with a monitoring system, the fan
should still be subject to daily physical examinations because a fan
monitoring system is not capable of disclosing all conditions that a
physical inspection could disclose. The final rule does not adopt this
suggestion. A weekly physical examination of the fan and a test of the
monitoring system coupled with a daily review of the monitoring data
provides reasonable assurance that a mine fan is operating reliably.
Commenters suggested that the proposed requirement of paragraph (b)(1)
requiring a daily review of main mine fan monitoring system data is
unnecessary and redundant. These commenters suggested that the system
need only be capable of producing a printout because the systems would
automatically alarm anytime an electrical or mechanical deficiency
exists. Requiring a daily review of the monitoring system data,
according to these commenters, could discourage the use of improved
technology. Other commenters noted that operators currently using fan
monitoring systems conduct a daily review of the data at the present
time and that the requirements to review the data would provide an
additional measure of safety for the miners. MSHA believes that a daily
review of data from fan monitoring systems is needed to assure that
mine management is made aware of any operational changes or trends in
monitored parameters. Main mine fans provide the source for mine
ventilation and, therefore, are critical to miners' safety. As
discussed earlier, these daily reviews of data are designed to
complement the physical examinations of the fan.
The final rule adopts the requirements of proposed paragraphs
(b)(1)(ii) (A) and (B) and requires that when a fan monitoring system
is used as provided under paragraph (a), a trained person designated by
the operator must test the system for proper operation at least every 7
days. Commenters objected that it is redundant because a fan monitoring
system is capable of monitoring itself and can automatically provide a
warning when a fan malfunction occurs. These commenters also stated
that if the
[[Page 9771]]
system is continuously operated, the system is self-tested for proper
operation several times a minute and that the 7-day test is
unnecessary. The commenters suggested that the 7-day test only be
conducted if the fan monitoring system is not continuously operated.
For continuously operating fans an examination of the fan should more
appropriately be conducted monthly, according to these commenters.
Requiring more frequent checks the commenters maintain would discourage
the use of fan monitoring systems.
The final rule does not adopt these suggestions. While MSHA
encourages the use of fan monitoring systems, excessive reliance on the
self-monitoring features of these systems is incompatible with the
importance of reliable operation of main mine fans. MSHA does not
anticipate that the final rules for examination requirements will
discourage the use of fan monitoring systems. Main mine fans without a
monitoring system are required to be examined daily, while fans with
monitoring systems are required to be examined every seven days.
Paragraphs (c) and (d) of Sec. 75.312 of the final rule continue in
effect the requirements that tests of the automatic fan signal device
and automatic closing doors, when these doors are required, be
conducted at intervals not to exceed 31 days. The specified means of
testing these devices and doors is by stopping the fan. The proposal
would have permitted an alternative test not involving stopping the fan
if the alternative method provided the same level of assurance that the
signal device or door would function as intended during fan stoppages.
Two commenters favored the proposal and suggested that there is no need
to approve alternate means of testing fan signal devices in the mine
ventilation plan. These commenters expressed the opinion that each
authorized representative should be capable of ascertaining the
validity of the alternative method. The commenters did not make a
similar suggestion relative to the alternative means provision proposed
in paragraph (d) for automatic closing doors. Another commenter opposed
the use of alternative tests stating that it would be premature to
adopt a provision for an alternative test to stopping the fan when such
a test has not as yet been developed. MSHA has reconsidered the
proposal and the final rule continues to require that the tests of fan
signal devices and automatic closing doors be conducted by stopping the
fan. Should an operator develop an alternative method that provides the
same level of protection as stopping the fan, the petition for
modification process is available for an operator to obtain approval.
Paragraphs (c) and (d) permit underground power to remain energized
during fan signal and automatic closing door testing, notwithstanding
the requirements of Sec. 75.311. If the fan is not restarted within 15
minutes, the final rule requires that underground power be deenergized
and no one is permitted to enter any underground portion of the mine
until the fan is restarted and an examination is conducted.
Additionally, paragraphs (c) and (d) require that only persons
necessary to evaluate the effect of the fan stoppage or restart, or to
perform maintenance or repair work that cannot otherwise be done while
the fan is operating, are permitted underground.
Some commenters objected to limiting the persons who can be
underground during fan signal and closing door tests. Other commenters
objected to anyone being permitted underground during the stoppage of a
fan to conduct the required tests. These commenters expressed the
opinion that all necessary work can be performed with the fan operating
and therefore, when a fan is shut down to test the fan signal device or
the automatic closing doors no one should be underground.
Some work, such as working immediately inby a blowing fan, could
place workers at risk by exposing them to extreme temperatures, effects
of the high velocity air stream, or excessive noise levels when the fan
is operating. In addition, repair work within a shaft can more safely
be done when a fan is stopped. The rule, therefore, retains the
exception that permits persons underground during intentional fan
stoppages to evaluate the effect of the fan stoppage or restart, or to
perform maintenance or repair work that cannot otherwise be done while
the fan is operating.
Paragraphs (c) and (d) of the final rule are reworded to clarify
that during the required tests, power circuits may remain energized
only if no person is underground. Therefore, if an operator elects to
evaluate the effect of the fan stoppage or restart, or to perform
maintenance or repair work that cannot otherwise be done while the fan
is operating, simultaneous with the tests required, power circuits must
be deenergized in accordance with Sec. 75.311(b)(3). Additionally, in
accordance with Sec. 75.311(b)(2), all mechanized equipment must be
shut off.
Paragraph (f)(1) of the final rule retains the longstanding
requirement that the person performing main mine fan examinations
certify by initials and date at the fan or another location specified
by the operator that the examinations were made. Each certification is
required to identify the main mine fan that was examined. When daily
fan examinations are conducted, daily certification is required. When a
main mine fan monitoring system is used and fan examinations are
conducted at 7 day intervals, certification is required each time the
fan is examined.
One commenter offered suggested wording that would eliminate the
option of certifying that the examination was completed at a location
other than the fan being examined. This suggestion has not been adopted
and the final rule retains the flexibility for certifications to be
made away from the fan.
Paragraph (f)(2) of the final rule requires that when a main mine
fan monitoring system is used, a daily printout of the system's data
must be certified to indicate that the daily review was completed.
While some commenters generally agreed with this requirement other
commenters suggested that an alternative should be provided for systems
which are continuously operated and supervised. In such cases, the
commenters suggested that immediate notification of the mine foreman
when a deficiency arises would be appropriate, together with
maintaining the internal records of data gathered by the systems for
one year.
The suggested alternative is not included in the final rule. MSHA
believes that documentation that monitoring system data is being
reviewed is necessary to provide reasonable assurance that mine
management is aware, on a timely basis, of the operating condition of
the fan being monitored. However, to reduce the burden of this
requirement, the final rule in paragraph (f)(2) does permit the
electronic certification of the review of the data generated by a fan
monitoring system. As with electronically kept records, the rule would
require that the electronic certification include handwritten initials
and dates. A discussion of comments concerning the use of computers to
maintain records can be found in the General Discussion of this
preamble.
Paragraph (g)(1) of Sec. 75.312 requires that by the end of the
shift on which the examination is made, persons making main mine fan
examinations must record all uncorrected defects found during the
examination that may affect the operation of the fan. The rule also
specifies that records be maintained in a book that is secure and not
susceptible
[[Page 9772]]
to alteration, or electronically in such a manner as to be secure and
not susceptible to alteration. The proposal would have required all
defects found during the main mine fan examination that may affect the
operation of the fan to be recorded whether corrected or uncorrected.
Some commenters objected to recording defects that ``may'' affect
the operation of the main mine fan, and suggested only defects that do
affect the operation of the main mine fan and that are not corrected by
the end of the shift, need to be recorded.
Some commenters asserted that a record of ``all'' defects should be
required in order to identify recurring problems that may lead to
bigger problems. These commenters interpreted the proposal to require
such a record. The final rule is intended to address problems found
during fan examinations that may indicate more serious defects and
ultimately lead to a fan failure and that cannot be corrected by the
end of the shift. The objective is to record defects of a nature and
seriousness that could result in a fan failure, but not to record
defects that are so minor that it would be unreasonable to expect fan
failure to result. Another commenter stated that recording all defects
that may affect fan operation would result in excessive paperwork of
little value. This commenter also suggested that if mine ventilation
does become ineffective, the workers are to be withdrawn from the mine.
MSHA is sensitive to concerns about recordkeeping. Therefore, the final
rule requires that all uncorrected defects which are found during the
examination that may affect fan operation be recorded. In this manner,
miners on the oncoming shift are aware of problems with the fan that
potentially could impact underground ventilation.
Commenters supported the use of electronic media as a substitute
for specific types of record books. Commenters pointed out that almost
all such systems incorporate recordkeeping functions and that
significant variances from the norm are easily noted. They concluded
that the computer monitoring systems provide superior protection for
the miners. The final rule permits, in paragraph (g)(1), the use of
electronically stored records for main mine fan examinations provided
the records are secure, are able to capture the information and
signatures required, and are accessible to the representative of the
miners and the representatives of the Secretary.
As with other records required by this rule, paragraphs (g)(2) and
(g)(3) require that records required by Sec. 75.312 must be made in
books that are secure and not susceptible to alteration, or
electronically in such a manner as to be secure and not susceptible to
alteration. A detailed discussion of record books and the use of
computers to maintain records can be found in the General Discussion of
this preamble.
Paragraph (g)(2) of the existing rule requires that at mines
permitted to shut down main mine fans under Sec. 75.311, if a pressure
recording device is not used, a record shall be made, in a book
maintained for that purpose, of the time and fan pressure immediately
before the fan is stopped, and after the fan is restarted and the fan
pressure stabilizes. The final rule does not retain this requirement in
light of the new requirement of Sec. 75.310(a)(4) that all main mine
fans be provided with a pressure recording device or an option of the
use of a fan monitoring system. This new requirement eliminates the
need for an additional record of the time and fan pressure made
immediately before the fan is stopped and after the fan is restarted
and the fan pressure stabilizes. This information is obtained from the
pressure recording chart, which records the pressure continuously and
automatically, thus maintaining the protection afforded the miners.
Paragraph (h) of the final rule requires that the records required
by Sec. 75.312 be maintained at a surface location at the mine for one
year and be made available for inspection by authorized representatives
of the Secretary and the representative of miners. Comments were
generally favorable on this proposal. A discussion of comments
concerning the use of computers to maintain records can be found in the
General Discussion of this preamble.
As with the other provisions of the final rule allowing electronic
certification or recordkeeping, sufficient protections have been
included so that there is no reduction in protection from the existing
standards.
Section 75.313 Main Mine Fan Stoppage With Persons Underground
Section 75.313 was stayed by MSHA as explained in the introductory
section of this preamble. Generally, this standard is concerned with
protecting miners from the danger introduced when the main mine fan
stops, such as when there is a loss of power. Under these
circumstances, mine ventilation is interrupted, permitting gases such
as methane to accumulate. These conditions can lead to an explosion
ignited by electric circuits or the operation of equipment.
Paragraph (a)(3) of the final rule requires that if a main mine fan
stops, everyone shall be withdrawn from the working sections and from
areas where mechanized mining equipment is being installed or removed.
The language of the final rule is identical to the wording of stayed
Sec. 75.313 (a)(3). An in-depth discussion of provisions concerning the
installation and removal of mechanized mining equipment is presented in
the General Discussion section of this preamble.
The final rule revises paragraphs (c)(2), (c)(3), (d)(1)(i) and,
(d)(1)(ii) of the stayed standard. Paragraphs (c)(2) and (c)(3) require
that when a main mine fan stops with persons underground, the
underground electric power circuits shall be deenergized and mechanized
equipment shall be shut off. These rules further recognize an exception
to facilitate miners' evacuation from the mine. The exception
temporarily permits some circuits to remain energized and some
mechanized equipment to not be shut off, provided these circuits and
mechanized equipment are necessary to withdraw persons from the mine
and are located in areas where methane is not likely to migrate to or
accumulate. These circuits must be deenergized and the mechanized
equipment must be shut off as persons are withdrawn. The final rule
differs from the stayed standard by limiting the exception permitting
the use of these circuits or equipment to areas where methane is not
likely to migrate to or accumulate.
Paragraph (d)(1)(i) requires that when a fan stoppage lasts for
more than 15 minutes a preshift-type examination must be conducted
before persons other than designated examiners, are permitted to enter
any underground area of the mine. Examiners are permitted to re-enter
the underground area of the mine from which miners have been withdrawn
only after the fan has operated for at least 15 minutes unless a longer
period of time is specified in the mine ventilation plan. Paragraph
(d)(1)(ii) requires that when a fan stoppage lasts for more than 15
minutes, underground power circuits are not to be energized and
nonpermissible mechanized equipment is not to be started until a
preshift-type examination is conducted, except that designated
certified examiners may use nonpermissible transportation equipment in
intake airways to facilitate the conduct of the required examination.
Some commenters suggested that actions following fan stoppages are
best handled on a mine-by-mine basis through a plan approval process.
Along
[[Page 9773]]
these lines, commenters suggested that the fan stoppage plan approval
process previously used by MSHA should be used with only minor
modification to assure that plans do not become standardized, that is,
model the rule on a past standard with criteria for approval of fan
stoppage plans. Other commenters, while supporting the concept of fan
stoppage plans, proposed to tie the submission and approval of such
plans to total mine ventilation surveys and computer simulations
conducted by the operator every three months. According to one
commenter the data provided by these surveys would be used to determine
the adequacy of a fan stoppage plan.
The final rule does not adopt the suggestions of the commenters for
mine fan stoppage plans. One objective in this rulemaking is to reduce
the need for paperwork, such as plans, where reasonable, uniform
requirements can be developed. The final rule establishes the general
requirement that after a fan stoppage lasting more than 15 minutes,
mine power and equipment is to be shut down. However, experience shows
that using transportation equipment to facilitate mine evacuation is
often necessary, provided this is done where gas is not likely to
accumulate, and circuits are deenergized on the way out of the mine.
Some commenters suggested that the requirements in paragraphs
(c)(2) and (c)(3) limiting the use of transportation equipment to areas
and haulageways ``where methane is not likely to migrate to or
accumulate'' are inconsistent with certain state laws. As support for
this assertion, the commenters gave the example of the state of
Illinois' requirements for evacuating mines following an interruption
in ventilation, which does not expressly recognize limited use of power
and equipment to facilitate evacuation. State mine safety laws,
including Illinois', are similar to the final rule provisions for
evacuation after a mine fan stoppage. As a general rule, state mine
safety regulations that are more stringent than MSHA standards are not
considered to be in conflict with federal regulations, and the more
stringent safety requirement applies. In this case, if the Illinois
regulation would not permit temporary use of power and equipment to
facilitate evacuation, then the state law would not be inconsistent
with MSHA.
Several commenters objected to the wording, ``where methane is not
likely to migrate to or accumulate,'' in paragraphs (c)(2) and (c)(3),
as being vague. Other commenters stated that the rule's requirement was
simply good practice that would be heeded by prudent mine managers.
MSHA agrees that the terms and objectives of the final rule are
understood in the mining community, and believes that the determination
of whether methane may migrate from adjacent areas and enter travelways
and haulageways used by miners during withdrawal should be made on a
mine-by-mine basis. Therefore, the final rule retains the exception
that power circuits may remain energized and mechanized equipment may
be operated only if located in areas where methane is not likely to
migrate to or accumulate.
Some commenters stated that history does not support the need for
the requirements of paragraphs (c)(2) and (c)(3). Mine fan stoppages
unquestionably result in the existence of unventilated areas and may
result in highly hazardous methane accumulations. Although there have
been a limited number of ignitions/explosions directly attributable to
the operation of transportation equipment during a fan stoppage, the
true measure of the potential hazard addressed by this standard can be
seen in the ignitions and explosions that were the result of the
operation of transportation equipment in unventilated areas. Examples
of such types of accidents include: The 1972 Itmann No. 3 explosion, in
which 5 miners died; the 1976 Scotia Mine explosion, in which 15 miners
died; the 1982 Virginia Pocahontas No. 6 Mine explosion in which 1
miner was injured; the 1983 McClure No. 1 Mine explosion, in which 7
miners died; the 1983 Homer City Mine explosion in which a mine
examiner was killed; the 1983 Greenwich Collieries No. 1 Mine explosion
in which 3 miners were killed and 4 miners were injured and; the 1993
explosion at the Buck Mountain No. 2 Mine in which 3 miners were
injured. Given this history of explosions, it would not be prudent to
permit electric circuits to remain energized and mechanized equipment
to be operated in areas or haulageways where methane is likely to
migrate to or accumulate during a fan stoppage.
One commenter stated that the in-mine test necessary to determine
the likelihood of methane migration could only be done with the fan
stopped. The commenter questioned whether miners would be permitted
underground during the tests. To the extent the tests require the main
mine fan to be turned off, persons would be allowed underground to
evaluate the effect of the fan stoppage or restart.
Paragraphs (d)(1)(i) and (ii) address safety precautions for
reentering the mine after ventilation is restored. Key objectives of
these standards are the protection of the examiners and the safety of
miners returning to work.
As proposed, paragraph (d)(1)(i) would have required that when a
fan stoppage lasts for more than 15 minutes a preshift- type
examination be conducted covering the requirements of Sec. 75.360(b)
through (e) before persons, other than designated examiners, enter any
underground area of the mine. Commenters suggested that to provide the
level of protection desired, a complete preshift examination, including
the certification and recordkeeping requirements of Sec. 75.360(f)
through (g), should be required. Commenters pointed to the need for
miners reentering evacuated areas to be able to determine if the area
had been examined and urged that the final rule require the examiner to
certify by initial, date and time the areas examined.
MSHA agrees that clear notice to miners about which areas have been
examined is necessary and consistent with the objectives of the rule.
The final rule, therefore, adopts the proposal. A record of the
hazardous conditions found by examiners is required under Sec. 75.363
of the final rule. This record serves the purpose of providing mine
management with the information necessary relative to the existence and
correction of hazardous conditions in the mine. The final rule
incorporates these requirements by specifying that the scope of the
examination be conducted as described in Sec. 75.360(b) through (e).
Under paragraph (d)(1)(i) no one other than designated certified
examiners would re-enter any underground area of the mine until the
entire examination is completed. Commenters suggested that paragraph
(d)(1)(i) be revised to permit partial examinations following fan
stoppages and restarts under certain conditions. Under this suggested
approach, the examination would focus on the effectiveness of the
mine's ventilation system and methane accumulations in travelways, work
places or other areas where miners will work following the interruption
of ventilation. One commenter further suggested that an exception to
this examination be provided for noncoal producing shifts, where
persons are to work in the shaft, slope, drift, or on the immediate
shaft or slope bottom area. The commenter suggested the examination
following a fan stoppage could be limited to this area.
The final rule does not adopt this approach. Limiting the scope of
examinations following an interruption in mine ventilation to general
[[Page 9774]]
ventilation effectiveness and methane accumulation would not focus on
likely areas of concern. For example, no examination for hazards would
be required, and no air measurements to determine if the air is moving
in its proper direction and at its normal volume would be required. As
to the area of the mine required to be examined, only those places
where miners will return to work and the route of travel used to reach
these places must be examined. Thus, the final rule is sufficiently
flexible to meet the commenter's concerns about non- coal producing
shifts.
A question arose during public meetings as to the meaning of the
term on-coming shift in Sec. 75.360 when applied to Sec. 75.313. For
the purposes of Sec. 75.313(d)(1)(i) and (ii) the term ``persons on the
on-coming shift'' is interpreted as meaning persons on the shift on
which the fan is restarted. If a fan outage extends from one shift into
another, a preshift examination as required by Sec. 75.360 must be
completed before any person, except certified examiners designated to
conduct the examination, enters the mine.
Commenters also suggested that the final rule specify a minimum
time for the fan to run before examiners re-enter the mine so that
examiners are not unduly exposed to danger. Several commenters observed
that this is a general practice in the industry.
MSHA agrees that an important measure of safety is gained by
allowing the mine fan to run sufficiently long to begin reventilating
the mine before anyone enters. The final rule, therefore, provides
designated certified examiners shall enter the underground area of the
mine from which miners have been withdrawn only after the fan has
operated for at least 15 minutes unless a longer period of time is
specified in the approved mine ventilation plan. The 15 minute
provision will permit re- ventilation of entries in which examiners
will travel to take place and the examiners will then be traveling into
the mine in fresh air.
Proposed paragraph (d)(1)(ii) would have required that when a fan
stoppage lasts more than 15 minutes underground power circuits are not
to be energized and nonpermissible equipment is not to be started until
a preshift-type examination is completed. Commenters objected to the
proposal for various reasons. One commenter suggested that before power
is permitted to be energized a complete ventilation survey should be
required. Other commenters focused on the practical considerations
involved in conducting examinations and urged that use of
nonpermissible equipment for the transportation of examiners be
permitted.
As revised, paragraph (d)(1)(i) requires that the main fan when
restarted run for at least 15 minutes so that restoration of mine
ventilation is underway before anyone enters the mine. Once this is
accomplished, electrical circuits in shafts and slopes can be energized
safely as these areas are the first places to be reventilated by fresh
air. Accordingly, the final rule permits these circuits to be re-
energized after the mine fan has run for at least 15 minutes.
The final rule also permits examiners to use nonpermissible
equipment for transportation during the examination. The proposal would
have prohibited this practice. Some commenters supported the proposed
prohibition citing two mining accidents involving nonpermissible
equipment in unventilated areas. Other commenters objected to the
proposal not to allow the use of nonpermissible equipment to facilitate
examinations following the restart of a main mine fan. These commenters
stated that travelways and equipment roadways can be examined and
tested for the presence of methane, the results of the examination
called out, and typical nonpermissible transportation equipment placed
into operation to expedite the examination of the mine.
After considering all of the comments, MSHA has revised the
proposal and the final rule permits the use of nonpermissible
transportation equipment, in intake airways, to facilitate making the
examinations after an interruption in mine ventilation. Using
nonpermissible equipment in this fashion, in nonventilated areas, has
been a demonstrably safe practice for many years in the industry. In
addition, the requirement of running the fan for 15 minutes before
reentering the mine, together with keeping the transportation equipment
in the intake airways where the main ventilating current travels first,
provides the desired level of safety.
Under proposed paragraph (d)(2), if ventilation was restored to the
mine before miners reached the surface, all miners would have been
required to continue traveling to the surface. As proposed, designated
certified examiners would have been permitted to remain underground for
the purpose of beginning the required examination. The final rule does
not adopt the proposal and retains the language of the existing
standard.
While supporting the requirement that miners continue to the
surface after a fan is restarted, some commenters objected to
permitting certified persons to remain underground. These commenters
also took the position that once a fan has been off for more than 15
minutes, all efforts to restart the fan should be suspended, unless it
is known that it is safe to restart the fan. Other commenters expressed
significantly different views on both issues. A number of commenters
supported restarting the fan as soon as possible because the longer it
is off, the greater the potential hazard. MSHA concurs with this
reasoning and the final rule adopts this approach.
On the issue of requiring the evacuation to continue once it has
begun until the fan is restarted, even when ventilation is restored, a
number of commenters objected that such a requirement would result in
unnecessary delays and may result in additional safety risks. One
commenter stated that the proposal would not allow for the variables
that exist from mine to mine. Several commenters suggested that if the
operator has reason to believe that the time frame of the fan stoppage
would be less than the travel time or equivalent, the dangers of
traveling outby into possible pockets of dangerous gas buildup (or
other travel hazards) far outweigh the dangers of staying on the
section in intake air back from the face. This would also allow the
miners to remain on the section and proceed to the working places after
the fan has restarted and the working places have been examined by a
certified person.
MSHA disagrees with this position. In some mines, the time to
travel from the outside to the working sections can approach 1 hour.
Following the approach suggested, miners would remain on the section in
an unventilated mine for up to 1 hour. If at the end of this time
ventilation is still not restored, it is unclear whether the miners
then proceed to the surface, traveling through the same area the
commenter suggested might be hazardous some 45 minutes before.
The commenters stated further that, ``Forcing miners to walk out of
the mine could take hours and unnecessarily delay the restoration of
ventilation and resumption of operations.'' While there may be
instances where the time required to withdraw miners is increased, the
requirements in paragraphs (c)(2) and (c)(3) have no impact on the
restoration of ventilation. In fact, MSHA's position is that
ventilation should be restored as soon as possible following a fan
stoppage.
Lastly, a number of commenters suggested that when ventilation is
restored during evacuation, miners should be permitted to remain where
[[Page 9775]]
they are and return to working areas after an examination of inby areas
is completed. These commenters stated that no additional measure of
safety is gained by requiring miners to continue to the surface if
ventilation has been restored and the area in which the miners are
located is free of hazards. MSHA agrees and has retained the language
of the existing rule. By retaining the existing language, the general
practice of miners stopping their evacuation and waiting for examiners
to complete their work will continue. Under this approach, miners
remain in a safe location while ventilation of the mine is restored.
They do not return to any area of the mine until it has been determined
to be safe. The final rule does not prevent mine operators from having
miners continue to the surface if they so choose. Regardless of whether
miners remain where they are or continue to the surface, paragraph
(d)(1)(i) of the final rule requires that the fan operate for at least
15 minutes before the examination of the areas from which miners have
withdrawn is examined.
Section 75.320 Air Quality Detectors and Measurement Devices
Section 75.320 establishes the standards for the devices relied
upon to test for the presence of methane and other dangerous gases that
can accumulate in a mine. It generally requires that these devices be
approved and maintained in permissible and proper operating condition.
The final rule adds a new paragraph (e). It requires that
maintenance of instruments required by paragraphs (a) through (d) of
Sec. 75.320 to detect and measure air quality be done by a trained
person. The final rule does not include the proposal that before each
shift care shall be taken to assure the permissible condition of the
air quality detectors and other measurement devices to be used during
the shift. MSHA has concluded that this requirement would have been
redundant with paragraph (a) and is unnecessary. The final rule permits
an operator to send instruments to a repair facility or to the
manufacturer for regular servicing. Commenters at the informational
meetings and in later discussions on the existing rule stated that
maintenance by trained persons should be specified and that requiring
only that air quality detectors and other measurement devices be
maintained in permissible condition would not be sufficient. They
stated that without a requirement for maintenance to be done by a
trained person, similar to that which existed in the previous standard,
a person with less than the necessary understanding of the instrument
and the permissibility requirements might be assigned the task.
Several commenters suggested that the requirements of paragraph (e)
are redundant with general requirements found elsewhere in the
standards and are unnecessary. Other commenters felt that the current
performance standard is adequate, but that the meaning of ``assure'' is
unclear. Still other commenters indicated that the assurance of
permissibility is properly the responsibility of the user. One
commenter noted that the instruments are intrinsically safe and that
the manufacturer's instructions are sufficient. MSHA agrees that the
general requirement under paragraph (a), together with requiring
trained persons, is adequate.
Another commenter suggested that a formal written maintenance
program be required. Under this suggestion, the program would be
subject to MSHA approval and would include records of all maintenance
and calibrations to be made by the end of the shift. This commenter
also suggested that existing paragraph (a) be revised to provide for
more frequent calibration by inserting the phrase ``* * * or more often
if necessary * * *.'' This suggestion has not been adopted since
compliance with the proper operating and permissibility provisions of
paragraph (a) would result in more frequent calibration, if necessary.
MSHA notes that under the previous standard, there was no written
maintenance program required nor were records required. MSHA believes
that experience under both the previous and existing standards
demonstrates that, with the addition of paragraph (e), maintenance and
calibration is appropriately addressed in the final rule and safety is
not reduced.
Several commenters agreed with the proposal for a ``trained''
person to maintain air quality detectors and measurement devices. These
commenters suggested that the trained person be defined as a person
designated by the operator who has received training through experience
in maintenance of the instrument, has been trained by an experienced
person, or one who has received training by or through the instrument
manufacturer. MSHA has not adopted this suggestion since the operator
should have some flexibility as to the mode of training. The
requirement that the person performing the maintenance must be trained
is intended to mean that the person be capable of doing the required
maintenance, not that they receive a specific course of instruction in
what to do.
Commenters suggested that maintenance and calibration requirements
should parallel those proposed under Sec. 75.342 for machine-mounted
methane monitors. They suggested that, because the detectors and
monitors perform similar functions, the requirements should be similar.
The final rule does not adopt this suggestion. The methane monitoring
instruments under this standard and those governed by Sec. 75.342 are
subject to different mining conditions. For example, machine-mounted
monitors must be calibrated and maintained underground, on the
equipment on which they are installed and on working sections. This
calibration must also be scheduled within production timetables.
Handheld detectors and measurement devices, however, are removed from
the mine and are maintained and calibrated in surface environments.
Calibration and maintenance of handheld detectors is usually done
during shifts when the instruments are rotated out of service. Thus
machine-mounted monitors are calibrated and maintained under more
strenuous conditions than handheld detectors.
One commenter suggested that written records of all maintenance and
calibration should be required. The commenter further suggested that:
Each operator submit a written maintenance program to MSHA for approval
and provide a copy to the miner's representative; the written program
specify training to be provided; records be completed by the person
performing maintenance and be countersigned by the mine foreman within
24 hours; and that records be maintained for one year and be made
available to MSHA and the representative of the miners. These
additional requirements were not included in the proposal and are not
adopted in the final rule. The requirements contained in the final rule
adequately address and are appropriately related to the concerns
relative to maintenance, calibration, permissibility, and the general
condition of air quality detectors and measurement devices.
Section 75.321 Air Quality
The primary function of a mine ventilation system is twofold, to
remove hazardous gases such as methane, and to provide miners with an
respirable environment in areas where they are required to work or
travel. As discussed in the introductory section of this preamble,
Sec. 75.321 of the existing standard was stayed by the United States
Court of Appeals for the District of Columbia Circuit as it pertains to
bleeder entries. The final rule, in
[[Page 9776]]
Sec. 75.321, addresses acceptable levels of oxygen and carbon dioxide
in areas of a mine, including areas of a bleeder entry, where persons
are required to work or travel.
Paragraph (a)(1) continues a basic air quality requirement that has
been in place since 1970 that air in areas where persons work or travel
contain at least 19.5 percent oxygen and not more than 0.5 percent
carbon dioxide, and the volume and velocity of the air current in these
areas be sufficient to dilute, render harmless, and carry away
flammable, explosive, noxious, and harmful gases, dusts, smoke, and
fumes. Paragraph (a)(2) applies the same requirement for oxygen, 19.5
percent, for the air in areas of bleeder entries and worked-out areas
where persons work or travel. The final rule does not require the
carbon dioxide level of 0.5 percent to be applied to bleeder entries
and worked-out areas. Rather paragraph (a)(2) requires that the carbon
dioxide levels in the air in bleeder entries and worked-out areas where
persons work or travel not exceed 0.5 percent time-weighted average
(TWA) and 3.0 percent short-term exposure limit (STEL).
MSHA interpreted former Sec. 75.301 to require at least 19.5
percent oxygen and no greater than 0.5 percent carbon dioxide in
bleeder systems where persons work or travel. It was MSHA's intent that
existing Sec. 75.321 would necessitate compliance with these levels
where persons would be exposed in bleeder entries and in worked-out
areas. However, the application of this provision to bleeders and
worked-out areas was stayed by the United States Court of Appeals
pending the outcome of litigation addressing the promulgation of the
existing rule. MSHA continues to believe that providing necessary air
quality is essential to protect miners and examiners whenever they work
or travel in bleeder entries and worked-out areas. Therefore, the final
rule includes a new provision specifying that the air in bleeder
entries and worked-out areas where persons work or travel contain at
least 19.5 percent oxygen, and that carbon dioxide not exceed 0.5
percent TWA and 3.0 percent STEL. A TWA is the time-weighted average
concentration for a normal 8-hour workday and a 40-hour workweek. A
STEL is the maximum time-weighted average concentration to which miners
can be exposed for a continuous period of up to 15 minutes. Commenters
noted an error in the preamble to the proposal with respect to the time
an individual can be exposed to concentrations between the TWA and the
STEL. MSHA intends to apply TWA and STEL levels in a manner consistent
with the Air Quality rulemaking. The levels for carbon dioxide in the
final rule for areas where persons work or travel in bleeder entries
and worked-out areas are identical to the levels contained in MSHA's
proposed Air Quality standards for coal and metal and nonmetal mines
and the 1992 Threshold Limit Values (TLVs) as specified by the American
Conference of Governmental Industrial Hygienists (ACGIH).
Some commenters suggested that other changes be included in the
final rule. First, they recommended that the permissible minimum oxygen
level for bleeders and worked-out areas be lowered from 19.5 percent to
18 percent. Second, they suggested that the requirements that apply to
bleeders and worked-out areas be expanded to include airways associated
with bleederless mining areas. The rationale given for this second
recommendation was that the conditions in these airways are similar to
bleeders. In light of the ongoing Air Quality rulemaking, MSHA is not
at this time clarifying existing Air Quality standards except those for
worked-out areas and bleeder entries.
Commenters for the most part agreed with the change relative to
carbon dioxide although one commenter indicated that there was no need
for any standard. Bleeder entries and worked-out areas are required to
be traveled or evaluated at least weekly. Generally, this is done by a
person traveling alone who is often required to be in the bleeder
entries or worked-out areas for an extended period. The purpose of this
standard is to protect miners, not to regulate air quality where
persons are not exposed. Therefore, if examinations are performed
remotely or if persons making the examination can otherwise remain in
air that meets the requirements of the standard, oxygen and carbon
dioxide levels at bleeder connectors and bleeder evaluation points
would not have to meet the concentrations required by the final rule.
According to the National Institute for Occupational Safety and
Health (NIOSH) of the U.S. Department of Health and Human Services
(NIOSH Respirator Decision Logic, May 1987), 19.5 percent oxygen
provides an adequate amount of oxygen for most work assignments and
incorporates a safety factor. Also according to NIOSH, the safety
factor is needed because oxygen-deficient atmospheres offer little
warning of danger. In the NIOSH publication, ``A Guide to Safety in
Confined Spaces,'' (page 4), a chart is presented that indicates that
19.5 percent oxygen is the minimum level for safe entry into an area,
and that at a level of 16 percent, judgement and breathing are
impaired. The American National Standards Institute (ANSI), in ANSI
Z88.2-1992, ``American National Standard for Respiratory Protection''
recognizes that at 16 percent oxygen there is an impairment in the
ability to think and pay attention, and a reduction in coordination.
ANSI recognizes that at 19 percent oxygen there are some adverse
physiological effects.
The need for regulating the oxygen level where persons work or
travel in bleeder entries is illustrated by two mining accidents. One
of these accidents resulted in the death of a mine examiner and the
second resulted in the near death of two individuals, one of whom was a
mine examiner. Mine examiners are, through training and experience, the
individuals best able to identify the hazards associated with
irrespirable atmospheres. The first accident occurred at the Arclar
Mine in Equality, Illinois in 1989. Prior to implementation of the
existing standard, a mine examiner entered a worked-out area that was
posted with a danger sign and was asphyxiated. Under the existing
regulation, ventilation or sealing of this area, rather than posting,
would be required. Because the area was not sealed, the existing
regulation would require the area to be examined during the weekly
examination. The final rule would require that the route of travel for
the examiner contain at least 19.5 percent oxygen. Had the final rule
been in place when the examiner entered the worked-out area, the
accident may have been avoided.
The second accident, although not in a bleeder entry or worked-out
area, is illustrative of what can happen when individuals, including
mine examiners, are subjected to oxygen deficient air. In 1983 at the
Bird No. 3 Mine in Riverside, Pennsylvania, an assistant mine foreman,
a certified person, entered the mine for the purpose of conducting an
examination. After traveling approximately 1100 feet, the examiner
became dizzy, noticed that his flame safety lamp had extinguished and
withdrew approximately 200 feet where he sat down and apparently became
unconscious. A second individual upon entering the area in search of
the examiner also became dizzy but was able to withdraw to a location
that was not oxygen deficient. When the mine examiner regained
consciousness, his cap lamp battery had discharged and he traveled in
total darkness until he encountered a mine rescue team. Air samples
collected in the area where the mine examiner first became dizzy
[[Page 9777]]
indicated an oxygen level of about 16.8 percent, while other samples
collected nearby indicated oxygen concentrations of nearly 20 percent.
Because mine examiners are required to work or travel in areas
where oxygen-deficient air could occur without warning, and they
normally travel and work alone, there must be a requirement that
provides them the protection necessary for the performance of their
duties under these conditions. It is important that the level for
oxygen be established above that identified as resulting in impaired
judgement because it is essential that individuals traveling in these
areas remain highly alert. The hazards that can exist in bleeder
entries and worked-out areas include elevated methane levels, poor
footing, loose and unstable roof, and water accumulations. For this
reason, the final rule adopts a minimum level of oxygen of 19.5 percent
as recommended by NIOSH.
MSHA is also concerned with the effects of other gases often found
in bleeder entries. Section 75.322 of the existing regulation limits
the concentration of noxious or poisonous gases to the current (1971)
TLV's as adopted and applied by the ACGIH. Section 75.322 specifically
excludes carbon dioxide since it is covered by Sec. 75.321. However, so
the mining public will clearly understand the application of the
regulation, the final rule establishes a separate standard for carbon
dioxide levels for areas where persons work or travel in bleeder
entries and worked-out areas. The levels set by the final rule, 0.5
percent TWA and 3.0 percent STEL, when considered in conjunction with
the requirements of Sec. 75.322 and the requirement for oxygen, will
provide persons working or traveling in these areas with a safe and
healthful working environment. MSHA recognizes that the effects of
carbon dioxide are both chronic and acute and, therefore, sets both a
TWA and a STEL. NIOSH, in recommending a standard for carbon dioxide,
also recognized this and recommended a similar approach. The NIOSH
recommendation, made in a Criteria Document published in 1976, proposed
a TWA concentration of 1.0 percent and a ceiling value of 3.0 percent
not to exceed 10 minutes. In making this recommendation, NIOSH
recognized that there are additive stress effects of increased carbon
dioxide concentrations and exercise. As support for this, the NIOSH
document cites research that showed that healthy, trained subjects
exposed to 2.8 to 5.2 percent carbon dioxide at maximum exercise levels
experienced respiratory difficulty, impaired vision, severe headache,
and mental confusion; three subjects collapsed.
During rulemaking on the proposed air quality standard, NIOSH
recommended a 0.5 percent TWA and a 3.0 percent STEL. NIOSH made a
similar recommendation to the Occupational Safety and Health
Administration during that Agency's permissible exposure limit
rulemaking. Given the work environment in bleeder entries and worked-
out areas, as described earlier, MSHA believes that the regulatory
approach to bleeders and worked-out areas provided by the final rule is
necessary and appropriate. In addition to examiners, other miners may
be required to work in the bleeder entries and worked-out areas,
performing duties such as installing roof support, pumping water,
recovering materials or adjusting ventilation. The levels established
in the final rule would provide these miners with the necessary
protection.
Section 75.323 Actions for Excessive Methane
Section 75.323 establishes the actions that must be taken when
methane reaches certain levels. Methane is the most dangerous gas
encountered by miners working underground. When the level of methane
reaches 5.0 percent it is explosive. Section 75.323 generally
establishes action levels below this lower explosive limit to permit
appropriate actions to be taken by mine operators in order to prevent
an explosion.
The final rule adopts the proposal for Sec. 75.323. In doing so, it
revises paragraphs (b)(1)(ii), (c)(1), and (d)(2)(i) of the existing
standard. The rule clarifies that corrective actions at specified
methane levels must be taken ``at once'' and provides that actions for
excessive methane include areas where mechanized mining equipment is
being installed or removed. MSHA believes that final rule Sec. 75.323
increases the protection afforded by the existing standard.
Initially, the need for clarification was raised during
informational meetings and subsequent discussions after publication of
the existing rule. As discussed below, the final rule retains the
language of the proposal which is identical to the wording of the
previous standard.
Some commenters indicated that delays in remedial actions to reduce
methane were being experienced at some mines. These commenters
attributed delays to the deletion of the phrase ``at once'' in the
existing standard. These commenters also suggested that the phrase ``at
once'' conveys the proper sense of urgency to correct the condition.
Other commenters stated that the addition of the phrase ``at once''
does nothing to improve health or safety. MSHA has included the phrase
in the final rule for clarity.
Methane poses a significant hazard to miners when it is permitted
to accumulate without corrective action being taken quickly. MSHA has
always intended that corrective changes be made at once. The final rule
revises paragraphs (b)(1)(ii), (c)(1) and (d)(2)(i) to require that
these changes be made ``at once,'' the phrase used in former
Secs. 75.308 and 75.309.
Some commenters stated that the proposal, if literally enforced,
would necessitate changes to be made before the cause or source of the
increase in methane can be investigated. Other commenters stated that
approvals must be obtained for many ventilation changes and that some
changes require extended periods of time to complete. Operators may
take those actions necessary to abate imminent dangers or hazardous
conditions, or to safeguard persons and equipment. A part of this
action would be a determination of the cause of the problem. MSHA knows
of no case where an operator has been prohibited from a necessary
correction for a methane problem pending a plan approval. However, in
cases where intentional changes are made which could materially affect
the safety and health of miners, approval is required before resumption
of normal work if the changes affect the information approved in the
mine ventilation plan. MSHA recognizes that some ventilation changes
take time to accomplish and interprets the phrase ``at once'' as
meaning that the work of making the necessary change to reduce methane
levels begins immediately.
One commenter questioned how the phrase ``at once'' would apply to
a methane feeder which is encountered despite an appropriate and well
thought out ventilation change. MSHA recognizes that methane feeders
may be encountered unexpectedly. As long as a mine operators takes
action as required by the standard, they will be in compliance.
One commenter suggested that some MSHA personnel were improperly
interpreting methane excursions above 1.0 percent to be violations of
the standard. The commenter seemed to suggest the regulations should
provide that the actions specified in Sec. 75.323 for excessive methane
do not apply to concentrations detected on machine-mounted methane
monitors. Other commenters indicated that the standard requires
unnecessary ventilation
[[Page 9778]]
changes in response to instantaneous increases caused by excessive
methane liberation. MSHA recognizes that instantaneous methane monitor
readings for machine mounted monitors may occasionally reach or exceed
1.0 percent. Usually, these are short-lived and the monitor reading
quickly falls below 1.0 percent, even before the machine operator can
react. However, consistent monitor readings of 1.0 percent or more
indicate a problem and should cause appropriate changes and
adjustments. Repeated short duration increases above 1.0 per cent
should also be cause for concern and may necessitate changes or
adjustments to ventilation.
With respect to paragraphs (b)(1), (b)(2), and (c)(1) some
commenters stated that the mere presence of methane does not constitute
a violation of a mandatory health and safety standard. MSHA agrees. In
this context, one commenter suggested replacing the word ``present''
with ``detected.'' The commenter continued that an operator cannot
possibly correct a methane problem until it has been detected, that the
rule should reflect realistic expectations, and that the current term
``present'' is meaningless. MSHA agrees that a methane problem cannot
be corrected unless it has been detected and that the mere presence of
methane does not constitute a violation. Only the failure to properly
respond once being made aware of the presence of methane in excess of
allowable levels is a violation. The standard requires that an operator
properly conduct an examination; and if methane over 1.0 percent or 1.5
percent is found, as applicable, corrective action must be taken at
once.
When 1.0 percent or more methane is present in a working place, an
intake air course, or an area where mechanized mining equipment is
being installed or removed, paragraph (b)(1)(i) of the final rule
requires all electrical, diesel, and battery- powered equipment in the
affected working place, intake air course, or other area, except for
intrinsically safe AMS, to be deenergized or shut off. Deenergizing or
shutting off of this equipment protects miners by preventing this
equipment from providing ignition sources.
One commenter suggested that non-intrinsically safe AMS equipment
should be permitted to run under battery power when 1.0 percent or more
methane is encountered. The commenter stated that the benefit derived
through the system's operation outweighs the hazard of the non-
intrinsically safe system. The commenter continued that since the
batteries will deplete quickly, little hazard would result, or in the
alternative, each battery outstation could be monitored for methane and
automatically trip at some set methane level. The final rule does not
include this suggestion. Where excessive methane concentrations
necessitate that power be deenergized, information from continued
operation of the non-intrinsically safe system would not outweigh the
potential ignition hazard. To permit operation of a non- intrinsically
safe system in areas known to contain excessive levels of methane would
be a departure from accepted, effective, and long standing safety
practice.
Several commenters objected to the requirement in paragraph
(b)(1)(iii) that prohibits any work in the affected area until the
methane is reduced to less than 1.0 percent. Commenters questioned
whether the standard would prohibit an operator from taking steps to
reduce the methane. The language must be given a reasonable
interpretation and should be considered in context of the preceding
requirement in paragraph (ii) that ``changes or adjustments shall be
made at once * * * ''
These requirements are virtually identical to those found in the
previous standard which was in effect for over 20 years. MSHA is
unaware of any instance where an operator was prohibited from
correcting methane problems by such an application of the standard.
Some commenters suggested adding a phrase to paragraph (b)(1)(iii)
to read, ``No work other than removal of the accumulation shall be
permitted * * * '' Similarly, MSHA believes that the suggested change
is unnecessary and has not adopted it. MSHA experience indicates that
the rule is well understood and has been properly applied.
Other commenters thought that the standard, as proposed, would
cause hasty, ill-advised changes to be made and would prohibit an
investigation into the cause or source of the methane problem which
could result in phased-in corrections. MSHA agrees that operators
should seek long term solutions and should fully investigate the cause
or source of methane accumulations. Investigation and long term
corrections are not prohibited by the rule. However, the final rule
does require that certain actions be undertaken at once to correct the
short term or acute safety hazards resulting from accumulations of
methane.
If 1.5 percent or more of methane is present in a working place, an
intake air course, or an area where mechanized mining equipment is
being installed or removed, paragraph (b)(2) of the final rule requires
persons to be withdrawn from the affected area. The presence of methane
in these areas can pose a significant risk to miners and therefore
their withdrawal from the affected area is essential to their safety.
Paragraph (b)(2) also requires that all electric power to equipment in
affected areas be disconnected at the power source. This prevents
accidental energization of equipment and removes power from cables and
circuits which may also be ignition sources. No other work is permitted
in the affected area until the concentration of methane is less than
1.0 percent. A conforming change is also made to paragraph (b)(2) by
adding ``mechanized'' before mining equipment for consistency with
other provisions of the rule.
Comments were received which objected to the (b)(2)(ii) requirement
that except for intrinsically safe AMS, electrically powered equipment
in the affected area shall be disconnected at the power source. Some
commenters suggested that this equipment should be simply
``deenergized.'' These commenters stated that there was no need to
disconnect the power source, that this could require belt drives,
pumps, etc. to be physically disconnected where permanent connections
have been made, which could result in a major unnecessary operation.
MSHA has not adopted this suggested revision. MSHA issues numerous
citations and orders for damaged power cables, trailing cables, and
splices where the conductors are badly damaged or exposed. Each of
these citations and orders represents the presence of a potential
ignition source. Power cables would remain energized under these
conditions as would be the case if the commenters' suggestion were
adopted.
There are several aspects of Sec. 75.323 which were not proposed
for revision, but for which comments were received. Comments were
received relative to the 1.0 percent action level in intake air
courses. Commenters contended that Congress established an immutable
methane limitation of 0.25 percent in intakes. Commenters stated that
because Congress had expressly limited intakes passing openings to
abandoned areas to 0.25 percent methane, that implicitly, all intakes
were limited to 0.25 percent methane. However, the commenter then
suggested adopting an intake action level for methane of 0.5 percent.
MSHA notes that the methane levels were not proposed for revision and
are not being revised under the final rule. The commenters, however,
should refer to a discussion of this issue included in the
[[Page 9779]]
preamble to the existing rule dated May 15, 1992.
If 1.5 percent or more methane is present in return air, paragraph
(d)(2)(i) would require changes or adjustments be made ``at once'' to
the ventilation system to reduce the concentration of methane. Because
of the hazards presented by accumulations of methane, MSHA believes
that changes or adjustments should be made immediately and be made
independent of the mine ventilation plan in the interest of safety.
MSHA recognizes that some changes take time to complete. If operators
begin ``at once'' to make the necessary changes and adjustments, they
will be in compliance with the standard.
MSHA received comments relative to Sec. 75.323 which, although were
outside the scope of the rulemaking, demonstrate an incorrect
understanding of the existing rule. The limitations on methane content
and the associated actions required when excessive methane is
encountered are important components of a safety program to protect
underground miners. Therefore, several of these comments will be
addressed so that the mining community will better understand these
standards.
First, one commenter objected to the existing requirements in
Sec. 75.323(d). The commenter incorrectly stated that paragraph (d)
permits normal operations with 1.5 percent methane in working places.
Methane limits in working places and intake air courses is limited by
Sec. 75.323(b). Paragraph (b) specifies actions if 1.0 percent methane
is present, and withdrawal if 1.5 percent is present. Similarly,
Sec. 75.323(c) limits methane between the last working place on a
working section and where that split of air meets another split of air
to 1.0 percent and requires withdrawal at 1.5 percent. Paragraph (d)
modifies the requirement for that portion of the return split outby the
section loading point and has no effect on methane either in working
places or between the last working place and the point in the return
opposite the loading point.
One commenter indicated a preference for the language used in a
previous MSHA regulation, Sec. 75.308-1. The previous standard
restricted the changes or adjustments to increasing the quantity or
improving the distribution of air in the affected working place to an
extent sufficient to reduce and maintain the methane to less than 1.0
percent. The existing rule establishes a performance standard that
allows for several methods of compliance. One acceptable method of
compliance is to limit the rate of production of coal to permit the
existing ventilation system to maintain the level of methane below 1.0
percent. In all cases, however, increasing the quantity or distribution
of air continues to be an accepted means of reducing methane levels. No
safety benefit would be derived from disallowing reduced coal
extraction rates as a means of maintaining methane levels under 1.0
percent.
The final rule retains the language of proposed
Secs. 75.323(b)(1)(i), 75.323(b)(1)(iii), and 75.323 (b)(2)(i) and
(b)(2)(ii) which is identical to the wording of the existing standards.
An in-depth discussion of the reproposal of provisions concerning the
installation and removal of mechanized mining equipment is presented in
the General Discussion section of this preamble.
Section 75.324 Intentional Changes in the Ventilation System
This section addresses the precautions that must be taken when a
significant change is made to the ventilation system. MSHA did not
propose any change to existing Sec. 75.324 and is not making any
revisions in the final rule.
Questions had been raised concerning the language, ``materially
affect the safety or health of persons in the mine'' that appears in
the existing standard. The phrase is important in that it identifies
those ventilation changes that require approval of the MSHA district
manager under Sec. 75.370(c). MSHA regards it as impractical to follow
a ``cookbook'' approach to identifying what will or will not require
approval. Each particular circumstance is to be reviewed by the
operator on its own merits. To illustrate the Agency's expectations,
the following is a list of some examples of what MSHA considers
intentional changes that would materially affect the safety or health
of miners. These examples are not meant to include all possibilities,
but are meant to provide some general guidance: adding a new shaft;
bringing a new fan on line; changing the direction of air in an air
course; changing the direction of air in a bleeder system; shutting
down one fan in a multiple fan system; starting a new operating section
with ventilating quantities redistributed from other sections of the
mine; changing entries from intakes to returns and vice versa; and any
change that affects the information required by Sec. 75.371, Mine
ventilation plan; contents.
Comments were specifically solicited on issues raised in the
preamble discussion to the proposal. In response, written comments were
received from one commenter. These comments were reinforced by several
speakers at the public hearings. Other commenters indirectly referred
to Sec. 75.324 and stated that the phrase, ``materially affect the
safety or health of persons in the mine'' is accepted and understood by
the mining community.
One commenter suggested that the person designated by the operator
to supervise ventilation changes should be a certified person that is
knowledgeable of the mine's ventilation system. The results of changes
to a complex ventilation system are not always easy to predict, and for
that reason caution must be used when making significant changes to one
air split or several air splits. The balance of splits can be affected
and may result in air reversals, dead air spaces, or insufficient air
flow in critical areas. For this reason, such changes must be evaluated
by a certified person examining the affected areas to determine that
the areas are safe before production is resumed. Therefore, the Agency
believes that it is to be an unnecessary burden to also have
ventilation changes supervised by a certified person. Thus, the
suggestion of the commenter has not been adopted in the final rule.
This commenter also suggested that the provisions of Sec. 75.324
should apply to all intentional changes which alter the air current in
any section or area of the mine by 10 percent or more, or by 9,000 cfm
or more, whichever is less and that such change be considered to affect
the entire mine. The commenter recommended the miners' representative
be afforded the right to accompany the certified person to evaluate the
effects of the ventilation change and that a preshift examination of
the mine be conducted to assure that the mine is safe before electric
power is restored.
The commenter also suggested that a record be maintained of all
ventilation changes to include the names of all persons involved with
the change, the date and time of the change, and results and locations
of air quality and quantity measurements taken both before and after
the change. The commenter stated that the record should be made in an
approved book within 24 hours of the change and that the record should
be signed and countersigned. Finally, the commenter recommended that
the mine ventilation map should be updated immediately after the
ventilation change is made and that within 24 hours of the change, the
updated map should be made available to the miners' representative and
a copy sent to the district manager. Section 75.370(c) requires that
any change to the ventilation system that alters the main
[[Page 9780]]
air current or any split of the main air current in a manner that could
materially affect the safety or health of the miners, or any change to
the information required in Sec. 75.371 shall be provided to and
approved by the district manager before implementation. The final rule
requires that this information be provided to the miners'
representative at least 5 days before submittal to the district manager
(See Sec. 75.370 for full discussion). MSHA believes that this
provision provides necessary protection for miners.
One commenter stated that the standard is reactive and that MSHA
routinely cites mine operators after a methane explosion or ignition.
MSHA believes that the standard is designed to assure that operators
are proactive and develop plans that prevent hazardous conditions. The
Agency anticipates that with the clarification provided through this
rulemaking, operators will obtain MSHA approval prior to making
intentional ventilation changes that materially affect the safety and
health of miners, thereby preventing potentially hazardous conditions.
When questions arise as to whether an anticipated change requires prior
approval, MSHA is available to provide guidance as to whether approval
is necessary.
Section 75.325 Air Quantity
The quantity of air in cubic feet per minute (cfm) is an important
measure of underground coal mine ventilation. It is essential for
miners' health and safety that each working face be ventilated by a
sufficient quantity of air to dilute, render harmless, and carry away
flammable and harmful dusts and gases produced during mining. An
insufficient quantity of air at a working face could permit methane to
accumulate and lead to an explosion. Section 75.325 generally
establishes the quantities of air that must be provided and the
locations underground where these quantities must be provided.
Section 75.325(d) requires that areas where mechanized mining
equipment is being installed or removed be ventilated and that the
minimum quantity of air and the ventilation controls necessary to
provide these quantities be specified in the approved mine ventilation
plan. The final rule adds the word ``minimum'' to the phrase,
``quantity of air'' that appears in the existing standard and the
proposal. The existing standard was reproposed without change. An in-
depth discussion of the reproposal of provisions concerning the
installation and removal of mechanized mining equipment is presented in
the General Discussion section of this preamble.
Only a few comments were received that were specific to paragraph
(d). One commenter discussing Sec. 75.371(r) suggested that the
quantity of air required by Sec. 75.325(d) to be specified in the plan
should represent the ``minimum'' quantity to be provided and that the
location specified should be identified as typical so as to give the
mine the flexibility to adapt to conditions. This comment is consistent
with MSHA's intent for the proposal and helps to clarify it. Therefore,
the word ``minimum'' has been inserted into the final rule in both
Sec. 75.371(r) and paragraph (d) of Sec. 75.325. Obviously, mine
operators can have air quantities which exceed the minimum specified in
the mine ventilation plan. MSHA agrees conceptually with a comment that
the ventilation scheme shown in the plan should be representative of
the method of ventilation to be used. However, MSHA does not adopt this
comment because the plan must also be specific enough so that the
operator, the miners, the representative of miners, and MSHA are
assured that the areas are being adequately ventilated.
Other commenters suggested that the total quantity of air to be
delivered to a longwall needs to be specified in the mine ventilation
plan. In support of the suggestion the commenter stated that the
inclusion of the word ``total'' recognizes that some mines may use belt
air at the set up or tear down phase while some intake air may be
diverted to ventilate bleeders, battery chargers or compressors and,
therefore, the total quantity of air being delivered to the longwall
face should be the figure with which MSHA is concerned. The commenter
stated further that the recommendation recognizes that conditions vary
greatly from mine to mine, coal seam to coal seam, even from one
longwall panel to the next panel of the same mine. The commenter added
that while a specified amount of air can be delivered to a recovery
face, and pressure can be placed on the gob, it is impossible to
guarantee a specified volume or velocity of air at the recovery point.
MSHA agrees that the total air quantity provided to a recovery face
is of importance; however, the distribution of this air is also
important. The volume of air being delivered to the longwall face
during equipment removal is important because of the types of
activities that occur (e.g. cutting and welding and the operation in
some cases of considerable numbers of diesel powered vehicles) and the
fact that it is along the face that the majority of miners work and
where an ignition hazard exists. It is important to know exactly how
areas where mechanized equipment is being installed or removed will be
ventilated. Therefore, this suggestion has not been included and the
rule.
Commenters were concerned about the ventilation of a longwall face
prior to the first gob fall. This type of concern should be handled
through the mine ventilation plan. Paragraph (d) only deals with areas
were mechanized mining equipment is being installed or removed and not
where mining is in progress.
Section 75.330 Face Ventilation Control Devices
The final rule adds a new paragraph (c) adopting the proposal
language. The new paragraph (c) requires that when line brattice or any
other face ventilation control device is damaged to an extent that
ventilation of the working face is inadequate, production activities in
the working place are required to cease until necessary repairs are
made and adequate ventilation is restored. MSHA notes that before
issuing a citation for a violation of this provision, an inspector
would normally be expected to measure the air quantity to determine
whether adequate ventilation is being maintained.
Some commenters considered the proposed regulation redundant since
operators must already maintain minimum air quantities at the face,
thereby making repairs necessary to maintain the required quantity.
Face ventilation controls are a critical feature of reliable
ventilation. As such, maintaining these controls in good condition and
making repairs necessary to restore ventilation is sound safety
practice. To do less invites increased risk of a methane ignition and
elevated respirable dust. Also on a practical level most miners on a
working section do not have a means of measuring air quantities.
However, miners can determine when ventilation controls are damaged
appreciably and are likely to adversely affect the air quantity.
One commenter indicated that entire working sections might be shut
down to repair a ventilation control at any one face with no
corresponding safety benefit. The final rule provides that ``production
activities in the working place shall cease'' until adequate
ventilation is restored. Unless elevated methane levels or some other
problem existed, the entire section would not be shut down for repair
of a ventilation control.
Some commenters asserted that controls may be slightly damaged
while still maintaining quantities in excess of
[[Page 9781]]
the requirements at the face. Similarly, commenters worried that
numerous citations would be issued based solely on the appearance of
the controls, even though the minimum required face air quantities are
exceeded. These commenters stated that the only reliable indicator is
an air measurement.
MSHA agrees that the only precise indicator of air quantity is a
measurement. Accordingly, MSHA anticipates that noncompliance decisions
will be based on air measurements which show ``ventilation of the
working place is inadequate.'' However, ventilation controls which are
in poor condition are likely to cue an inspector to conduct an air
measurement.
Other commenters generally expressed the view that the requirements
of Sec. 75.330, even considering the proposed revision, are inadequate
to fully address the issue of face ventilation. According to these
commenters, additional requirements are needed, including: proper
installation and maintenance criteria for face ventilation control
devices, requirements for providing devices continuously from the last
open crosscut to the working face, immediate repair of these devices if
damaged by a fall or otherwise, providing sufficient space between the
line curtain and the rib and maintaining the area free of obstructions,
and minimizing leakage while providing installations which permit
traffic to pass without adversely affecting ventilation. Further, the
commenters asserted that only cumulatively can the desired result be
obtained through these requirements and that additional requirements
would empower individual miners to take corrective actions when needed.
Each of these suggestions is a desirable ventilation practice which
MSHA supports. However, the final rule is not intended to set detailed
standards for the installation of ventilation control devices. Instead,
the rule addresses minimum requirements for face air quantities and
requires the face ventilation system used to deliver these quantities
to be maintained.
Some commenters indicated a concern about so-called ``deep-cut''
mining wherein continuous miners, by remote control, develop cuts from
25 to 60 feet inby permanent roof support. Commenters questioned the
adequacy of face ventilation where ventilation controls may be 30 to 50
feet from the face. Specifically, questions were raised about: whether
adequate ventilation actually reaches the face in ``deep cuts'' to
dilute methane; whether more frequent air measurements are needed;
whether methane checks are representative of face concentrations;
maximum feasible cut depth and ventilation device distance; respirable
dust in ``deep cuts;'' proper maintenance of ventilation control
devices; how ventilation is maintained after the continuous miner is
withdrawn from the cut; roof bolter ventilation; and differences
between scrubber systems and sprayfan systems. Another commenter noted
that historically most roof fall fatalities have occurred within 25
feet of the face. This commenter asserted that the deep-cut mining
system helps to resolve this problem and reduce exposure. The commenter
continues that to prohibit any variation from the 10 foot line curtain
distance requirement would adversely affect safety of the miners
working in the area.
MSHA agrees that each of these issues is important. The appropriate
vehicle to address these specific concerns is the mine ventilation plan
required by existing Sec. 75.370. The mine ventilation plan provides
the necessary latitude to address the diversity of mining conditions
found throughout the country. Details of each system must be shown in
the plan and must be specific to the conditions at each mine where such
a system is employed. Also, MSHA's review and approval of mine plans
includes an onsite investigation to evaluate the system and to assess
the adequacy of the specified plan parameters. In addition, inspectors
routinely evaluate the suitability of the mine ventilation plan during
regular mine inspections.
The commenter's concerns about methane checks in ``deep cuts'' is
addressed by the final rule Sec. 75.362(d)(2) which requires that
methane tests be made ``at the face.'' This new requirement will assure
that measurements are taken at the location where the hazard is most
likely to occur. Testimony received at the public rulemaking hearings
indicated that technology exists in the form of extendable probes that
can be used to take these measurements, without putting miners at
additional risk from fall of ground.
Section 75.332 Working Sections and Working Places
Working sections and working places are the areas of a coal mine
with the greatest amount of activity and the largest concentration of
workers. They are the location of the greatest number of potential
ignition sources. They therefore harbor the greatest risk of accidents
such as methane ignitions and explosions and equipment fires. Section
75.332 addresses the ways these areas are ventilated to reduce the
likelihood of an accident on one section impacting another section,
with deadly consequences. Generally, Sec. 75.332 provides that each of
these areas must be ventilated with a separate split of fresh air that
has not been used to ventilate another working area or an area where
mining has ceased if this area cannot be examined. When ventilated in
this manner, the products from a fire on one section will not
contaminate another section and methane in worked-out areas will not be
carried to working sections by the ventilating air stream.
The final rule provides that each working section and each area
where mechanized mining equipment is being installed or removed, shall
be ventilated by a separate split of intake air directed by overcasts,
undercasts or other permanent ventilation controls. The final rule
adopts the language of proposed Sec. 75.332(a)(1), which is identical
to existing Sec. 75.332(a)(1). An in-depth discussion of the reproposal
of provisions concerning the installation and removal of mechanized
mining equipment is presented in the General Discussion section of this
preamble.
Several commenters responded to Sec. 75.332(a)(1). Some commenters
suggested that the standard be revised to permit the installation of
mechanized mining equipment in either the return or intake air courses
of working sections provided the air had not been used to ventilate any
worked-out areas, areas where pillars have been recovered, or bleeder
systems. The commenters maintained that prohibiting the installation of
longwall equipment on the same split of air as a developing unit delays
the installation of a mining system. The commenters further observed
that this mining equipment consists mainly of steel conveyor sections
and roof supports that contain a 95 percent water-based hydraulic fluid
which does not burn. Therefore, according to these commenters, longwall
mining equipment can safely be installed on the intake side of an
active mining unit and, with monitoring, in the return air course of an
active mining unit.
The safety benefits of using separate splits of air to provide
ventilation are well established. A primary benefit of such a provision
is to protect workers down-wind from being put at risk by events up-
wind from their location. Among the most serious of these risks is
miners being overcome by the products of combustion or an explosion.
In Miner's Circular 50, ``Explosions and Fires in Bituminous-Coal
Mines'' published by the Bureau of Mines in
[[Page 9782]]
1954, the authors state that when air travels a long path through a
mine, it gradually becomes depleted of oxygen and may become so
contaminated with other gases that it no longer is healthful, or it may
accumulate enough explosive gas to present an explosion hazard. The
authors go on to state that when the air is divided into several
splits, each traveling a short path, better air can be furnished to
each group of persons in the mine. Further, if a local explosion or
fire should occur, the poisonous gases evolved may be confined to one
section and the force of the explosion and the gases may kill all the
persons in that particular section but may not affect other sections of
the mine. According to the authors, when a mine is ventilated by a
continuous current of air, the miners on the return side of an
explosion or fire probably will be killed or overcome by the poisonous
gases and that judicious splitting of the air is a safeguard against
this eventuality.
Similarly, Stefanko states in the 1973 edition of the Society of
Mining Engineers (SME) Engineering Handbook that splitting the air is
recognized as being necessary for safety and presents only minimal
power cost.
The commenters implied that because longwall mining equipment is
largely noncombustible, this danger is minimized for workers down-wind
on an active mining section. This reasoning overlooks the fact,
however, that the installation of a longwall is labor-intensive,
involving cutting and welding in the presence of methane and coal, as
well as machinery operating under load. These conditions add
contaminants to the ventilating current, and increase the possibility
of a fire or explosion. Likewise, a longwall being installed on the
return side of an active mining section would expose the miners doing
the installation to the dust and gases, and the results of a fire or
explosion, from the section. Even with monitoring, miners would be put
at risk as their opportunities for escape would be limited. For these
reasons, the final rule does not adopt the commenters'' suggestion.
One commenter also suggested that ``approved ventilation controls''
be required instead of specifying that overcasts, undercasts or other
permanent ventilation controls be used to direct intake air. The
commenter explained that this would allow operators the flexibility of
submitting plans that allow the use of temporary controls in some
instances.
Temporary controls to split air are not as reliable as permanent
controls. The first explosion at the Scotia Mine in 1976 which killed
15 miners, was due in part to the improper use of a temporary
ventilation control where a permanent control (i.e., an overcast)
should have been used. More recently, the explosion that occurred
during the set up of a longwall at the Golden Eagle Mine in 1991 which
injured 11 miners involved the removal of two permanent ventilation
controls and the replacement of these controls with temporary controls.
As these and other accidents illustrate, the ventilation controls that
deliver air to working areas are vitally important to miners'' safety.
Therefore, the final rule requires that these controls be permanent in
nature and not temporary.
Another commenter indicated that the use of temporary controls
would lower worker exposure to hazards by not requiring repeated
handling of permanent control materials which can be heavy. Proper
handling practices and modern materials can reduce the risk of injuries
associated with handling construction materials. MSHA considers these
risks lower than the dangers of using temporary controls in lieu of
permanent controls.
Section 75.333 Ventilation Controls
The primary means for directing air from the outside, through the
mine openings, to the working areas and back to the surface is through
the use of ventilation controls: either permanent controls, such as
stoppings (walls), overcasts or undercasts (air bridges), and doors, or
temporary controls, such as line brattice (curtains). Permanent
ventilation controls are designed for long term use while temporary
controls are intended for use on a short term basis. In general,
Sec. 75.333 specifies where each type of control can be used and how
each permanent control is to be constructed. It is essential that
ventilation controls be correctly constructed, maintained, and properly
located to provide ventilation to working sections and other areas
where it is needed to dilute methane, respirable coal mine dust and
other contaminants, and provide miners with a safe and healthful work
environment.
The final rule revises paragraphs (a), (b)(1), (b)(3), (b)(4) and
(e)(1) of existing Sec. 75.333, and adds a new paragraph (h). Revisions
to paragraphs (a) and (e)(1) address the durability of stoppings, while
the revisions to (b)(1), (b)(3) and (b)(4) address ventilation controls
required when continuous haulage systems are used. New paragraph (h)
requires all permanent ventilation controls, including seals, to be
maintained to serve the purpose for which they were built.
The use of continuous haulage systems, particularly in low seam
coal mines, is becoming more common. The final rule specifically
addresses continuous haulage systems in paragraphs (b)(1), (b)(3) and
(b)(4) of the rule and clarifies where temporary controls are an
acceptable means of ventilation control when these systems are used.
Continuous haulage systems utilize mobile bridge conveyors or similar
mechanisms to transport coal directly from a continuous mining machine
to a low profile belt. As the continuous mining machine moves from
place to place, the continuous haulage system slides back and forth
along a low profile conveyor belt using a ``dolly'' or other travel
mechanism. The low profile conveyor belt then transports the coal to
the section conveyor belt.
The existing rule permits the use of temporary ventilation controls
in lieu of permanent ventilation controls to separate continuous face
haulage systems from return, intake, and primary escapeway entries in
rooms developed 600 feet or less from the centerline of the entry from
which the rooms were developed. This practice is consistent with
longstanding MSHA policy, which recognizes that these rooms are used
for a short duration and the minimum air quantity must be maintained
regardless of the controls used.
Existing paragraph (b)(1) allows temporary controls to separate
intake and return air courses in rooms driven 600 feet or less from the
centerline of the entry from which the room was developed. The final
rule adds to existing paragraph (b)(1) the proposed language clarifying
that the use of temporary controls in these rooms is also acceptable
when continuous haulage systems are used. This change responds to
commenters who point out that the rooms in which the continuous haulage
systems are installed are continuously attended by the operators of the
system and an immediate response to any safety related problem with the
system or the ventilation controls would be expected. Commenters also
noted that two or three rooms are often concurrently developed using a
continuous haulage system and the life of the actively developing rooms
is often less than three days. As a result of this short life, mining
in these rooms is often completed before construction of permanent
controls is finished. Also, access to the continuous haulage system is
required through crosscuts for maintenance and operation of the system.
Under paragraphs (b)(3) and (b)(4) the proposal would have required
belt and
[[Page 9783]]
intake separation to the outby travel point of the dolly and belt and
primary escapeway separation to the inby most travel point. Commenters
indicated confusion because of the distinction between intake and
primary escapeway separation and believed that conflicts would exist.
Commenters also suggested that the language proposed to address the use
of temporary ventilation controls for continuous haulage systems was
confusing and contradictory. The final rule revises the requirements of
proposed paragraphs (b)(3) and (b)(4) to respond to these comments.
Paragraph (b)(3) of the final rule retains the requirement that
permanent controls be provided to separate belt conveyor haulageways
from intake air courses when the air in the intake air course is used
to provide air to active working places. The final rule also retains
the proposed provision that when continuous haulage systems are used in
rooms less than 600 feet from the centerline of the entry from which
the rooms were developed, temporary stoppings or other temporary
ventilation controls may be built and maintained to provide the
required separation.
Commenters stated that new technology may result in continuous
haulage systems with the outby point of travel of the dolly extending
considerably beyond the 600 feet distance. The commenters noted that
such an extended length of temporary controls could result in
unanticipated adverse consequences for the ventilation system, and
suggested that a maximum distance of 300 feet outby the inby point of
travel of the dolly be established for the use of temporary ventilation
controls. MSHA agrees that extensive use of temporary ventilation
controls can create problems, including excessive leakage and the
possible short circuiting of air. The final rule, therefore, limits the
distance that temporary controls may be used to separate continuous
haulage systems from intake air courses, including the primary
escapeway. The final rule permits temporary controls to be used from
the point of deepest penetration of the conveyor belt entry to the most
outby point of travel of the dolly or 600 feet, whichever distance is
the less. As a result, 600 feet is the maximum linear distance of entry
in which temporary controls may be used for separation of air courses.
The 600 feet would be measured as a straight-line distance from the
point of deepest penetration in the conveyor belt haulage entry. This
approach comports with the 600 foot limit for the use of temporary
stoppings in rooms and allows a reasonable use of temporary ventilation
controls with continuous haulage systems, while preserving the
integrity of the ventilation system. At present, MSHA would expect that
the most outby point of travel of the dolly would govern since MSHA is
not aware of any continuous haulage systems which travel more than 600
feet outby the point of deepest penetration.
Paragraph (b)(4) of the final rule continues to require permanent
stoppings or other permanent ventilation control devices to separate
the primary escapeway from the belt and trolley haulage entries, as
required by Sec. 75.380(g). Commenters suggested that for the purposes
of Sec. 75.380(g), the definition of loading point in proposed
paragraph (b)(4) be revised to be the outby point of travel of the
dolly as opposed to the inby point of travel. The final rule adopts
this suggestion and requires separation by permanent stoppings to be
maintained to the outby point of travel of the dolly or 600 feet from
the point of deepest penetration, whichever distance is less, to
separate the haulage entry from the primary escapeway. The provisions
of Sec. 75.380(g) continue to allow the district manager to require a
greater or lesser distance for this separation.
In response to questions about acceptable construction methods and
materials for permanent ventilation controls (excluding seals) MSHA
proposed eliminating the definition of ``durable'' in paragraph (a) and
to modify paragraph (e)(1). The proposal would have required these
controls to be constructed in a manner and of materials that result in
a construction that has been tested and shown to have a minimum
strength of 39 pounds per square foot as tested under ASTM E72-80
Section 12--Transverse Load-Specimen Vertical, load only (ASTM E72-80).
The 8-inch hollow-core concrete block stopping with mortared joints, to
which all other constructions were tied under the definition of durable
in the existing standard, has been tested and shown to have a minimum
strength of 39 pounds per square foot.
MSHA received numerous comments questioning the validity of the
ASTM E72-80 test for determining acceptability of underground
ventilation controls. Commenters questioned the appropriateness of a
strength requirement of 39 pounds per square foot and the relevance of
this value to the in-mine conditions. After review, MSHA continues to
believe that use of the ASTM E72-80 test to determine that the relative
strength of a ventilation control construction is appropriate and the
final rule retains this standard. However, MSHA sees merit in some of
the suggestions made by commenters. Commenters suggested that some
constructions can not be tested according to the ASTM test, some
constructions that are widely used in coal mines do not meet the 39
pound per square foot threshold, and the ASTM test can only be run at a
limited number of locations nationwide.
After reviewing all of the comments received and based on
experience with various construction methods and materials used for
permanent ventilation controls since the inception of the Mine Act, the
final rule recognizes traditionally accepted construction methods for
permanent ventilation controls, and retains the ASTM test for new
materials and methods. Controls made with new materials or methods must
be comparable in strength to controls made with traditionally accepted
materials or methods.
Since the inception of the Mine Act, a number of traditionally
accepted construction methods have performed adequately and have served
their intended function of separating air courses. These traditionally
accepted construction methods are: 8-inch and 6-inch concrete blocks
(both hollow-core and solid) with mortared joints; 8-inch and 6-inch
concrete blocks dry-stacked and coated on both sides with a strength
enhancing sealant suitable for dry-stacked stoppings; 8-inch and 6-inch
concrete blocks dry-stacked and coated on the high pressure side with a
strength enhancing sealant suitable for dry-stacked stoppings; steel
stoppings (minimum 20-gauge) with seams sealed using manufacturer's
recommended tape and with the tape and perimeter of the metal stopping
coated with a suitable mine sealant; and lightweight incombustible
cementatious masonry blocks coated on the joints and perimeter with a
strength enhancing sealant suitable for dry-stacked stoppings. In
addition, 4-inch concrete blocks may be used in the above applications
in seam heights less than 48 inches. Tongue and groove 4-inch concrete
blocks coated on both sides with a strength enhancing sealant suitable
for dry-stacked stoppings may be used in coal seams of any height. The
sealants referred to in this paragraph would be applied in the
thickness recommended by the manufacturer. MSHA maintains a list of
sealants which may be used for the above applications. This list is
available at each MSHA District Office. The final rule would continue
to permit these traditionally accepted construction
[[Page 9784]]
methods to be acceptable for the construction of ventilation controls.
For new construction methods or materials other than those used for
the traditionally accepted constructions identified above, the final
rule requires that the strength be equal to or greater than the
traditionally accepted in-mine controls. Tests may be performed under
ASTM E72-80 Section 12--Transverse Load-Specimen Vertical, load only,
or the operator may conduct comparative in-mine tests. In-mine tests
must be designed to demonstrate the comparative strength of the
proposed construction and a traditionally accepted in-mine control.
As with the existing rule, the final rule would require, in
paragraph (e)(1)(ii), that all overcasts, undercasts, shaft partitions,
permanent stoppings, and regulators, installed after November 15, 1992,
be constructed of noncombustible material. Also, like the existing
standard, the final rule lists materials that would be suitable for
these controls. The final rule would also continue to prohibit
ventilation controls installed after November 15, 1992, from being
constructed of aluminum.
Paragraph (h) of the proposal would have required that all
permanent ventilation controls, including seals, be maintained to serve
the purpose for which they were built. The final rule retains proposed
paragraph (h) with one revision. One commenter stated that the
paragraph should require all ventilation controls, including temporary
controls, to be maintained to serve the purpose for which they were
built. Given the importance of temporary controls devices in providing
for adequate ventilation, the final rule requires all ventilation
controls, both permanent and temporary, including all doors and seals,
to be maintained to serve the purpose for which they were built. This
standard applies to all ventilation controls, regardless of the
construction date.
Relative to seal maintenance, MSHA does not intend that the
maintenance requirement be applied to seals located within another
sealed area. Additionally, the rule does not apply to seals which have
become consumed within a gob area which is ventilated and evaluated in
a manner approved in the mine ventilation plan.
One commenter raised several questions concerning what MSHA would
consider to be an acceptable temporary stopping. MSHA has not defined
the term ``temporary ventilation control'' in the rule. The commenter
stated that, in the preamble to the proposal, MSHA refers to ``properly
constructed'' temporary stoppings but does not include a standard for
construction or installation and maintenance of temporary stoppings.
The commenter adds that temporary ventilation controls are a source of
potential leakage and are often susceptible to damage from roof and rib
falls and from mobile equipment. The commenter also refers to several
accidents where failure to maintain permanent or temporary ventilation
controls was a critical factor in the accident.
MSHA agrees that to properly direct the flow of air and provide for
adequate face ventilation, temporary controls, as well as all permanent
ventilation controls, must be installed and maintained in an adequate
manner to control leakage. MSHA has accepted as temporary controls,
check curtains or other flame- resistant material approved by MSHA that
are constructed and installed in such a manner to minimize leakage. As
required by paragraph (h) of this section of the final rule, these
controls must be maintained to serve the purpose for which they were
built.
Section 75.334 Worked-Out Areas and Areas Where Pillars Are Being
Recovered
Worked-out areas, areas where coal extraction has been completed,
can pose deadly hazards to miners, including an explosive methane
accumulation, irrespirable atmosphere, and the possibility of fire from
spontaneous combustion. Section 75.334 establishes the requirements for
ventilation of these areas to mitigate these hazards. In general,
Sec. 75.334 requires that following mining, these areas are to be
sealed or ventilated. Section 75.334 also specifies the requirements
for evaluating the effectiveness of the ventilation of worked-out areas
so operators can determine that the ventilation system is functioning
as intended.
The final rule revises paragraph (e) of the existing Sec. 75.334.
Existing paragraph (e) requires that each mining system be designed so
that worked-out areas can be sealed. The final rule adds to paragraph
(e) the proposed requirement that the location and sequence of
construction of proposed seals be specified in the approved mine
ventilation plan. Improper location and sequencing of seal construction
can have a dangerous effect on mine air quality and ventilation. As the
proper location and sequence of construction of seals is a mine-by-mine
determination, the mine ventilation plan provides the most workable
mechanism by which to assure proper air quality and ventilation of the
mine.
Several commenters objected to including seal construction sequence
as part of the information to be submitted for approval in the mine
ventilation plan. Their rationale was that mining conditions change and
could result in a change in the sequence of seal construction. The
construction might then be delayed while approval for the change is
obtained. These commenters suggested that in some cases, delays in seal
construction could result in a hazard to miners. Other commenters
stated that the sequence of construction of seals is more appropriately
and more easily shown on the mine ventilation map required by
Sec. 75.372. Another commenter stated that the sequence of construction
should be subject to approval because the placement of seals if
improperly installed can cause adverse effects on the ventilation
system and gob gases. MSHA is sensitive to the concern that a delay in
approval could result in a hazard to miners and, as explained in the
preamble discussion of Sec. 75.370, if a delay in seal construction
would result in a hazard to miners the review and approval of the plan
can be expedited.
MSHA agrees with the commenter that the location and sequence of
seal construction may be more easily, that is, more clearly shown on
the mine map required by Sec. 75.372 than in the written text of the
plan submitted under Sec. 75.371. The existing standard permits
appropriate information required under Sec. 75.371 to be shown on the
map required by Sec. 75.372. The effect is that the information both
appears on the ventilation map and in the ventilation plan and is
subject to approval. The discussion of Sec. 75.371(bb) further
addresses this point.
Spontaneous combustion is the process through which coal or other
materials self heat by the absorption of oxygen. Paragraph (f) of
Sec. 75.334 addresses mines with a demonstrated history of spontaneous
combustion and those located in coal seams determined to be susceptible
to spontaneous combustion. Paragraph (f) requires that the approved
mine ventilation plan for these mines specify the measures that will be
used to detect methane, carbon monoxide, and oxygen concentrations
during and after pillar recovery, and in worked-out areas where no
pillars have been recovered; the actions that will be taken to protect
miners from the hazards of spontaneous combustion; and, if a bleeder
system will not be used, the methods that will be used to control
spontaneous combustion, accumulations of methane-air mixtures, and
other gases, dusts, and fumes in the worked-out area.
[[Page 9785]]
Through meetings with various segments of the mining community,
MSHA became aware of a concern that paragraph (f) of existing
Sec. 75.334 may have been promulgated without the public being provided
the opportunity to adequately comment. Although MSHA believes that
existing paragraph (f) was promulgated properly, the Agency reproposed
paragraph (f) with wording identical to that used in existing
Sec. 75.334. The purpose of the reproposal was to assure MSHA received
and considered all pertinent comments.
Several commenters to the existing rule suggested that bleeder
systems should not be required for all mines. These commenters stated
that in some mines the practice of ventilating worked-out areas
increases the risk of spontaneous combustion by supplying oxygen to
combustion-prone materials in these areas. They also requested that the
final rule promulgated in 1992 include provisions to address
spontaneous combustion. MSHA acknowledged the need to reduce the flow
of oxygen to areas where there is a likelihood of spontaneous
combustion, and included in the 1992 rule requirements for mine
ventilation plans to address spontaneous combustion in mines with a
demonstrated history of this hazard or mines that are located in coal
seams determined to be susceptible to spontaneous combustion.
Experience gained through application of the existing standard has
demonstrated that a limited number of mines have experienced
spontaneous combustion problems. Studies by the Bureau of Mines have
identified the volatile properties of coal seams and have determined
that certain seams are susceptible to spontaneous combustion. The final
rule is directed to mines in these seams.
MSHA is not suggesting that all coal mines will meet the test to
show susceptibility to spontaneous combustion. A demonstrated history
or the determination of susceptibility to spontaneous combustion is a
prerequisite to the applicability of paragraph (f). While it is true
that all coal oxidizes when exposed to air, this fact is not sufficient
to make the determination that a coal seam is susceptible to
spontaneous combustion. MSHA would expect that absent a demonstrated
history of spontaneous combustion in a mine, an operator would provide
the necessary data to demonstrate that the mine is susceptible to
spontaneous combustion so that the provisions of paragraph (f) should
apply. A number of methods are used to determine the self heating
tendency of a coal.
However, MSHA is also mindful that some mines that have a
spontaneous combustion problem may be unable to reduce the oxygen
content to a sufficiently low level to mitigate spontaneous combustion.
For these mines, a bleederless system may not be appropriate. To
illustrate, it is well known that the oxygen level in a gob varies
depending on the location where the measurement is made. For example,
the periphery of a gob normally will have higher oxygen levels than the
interior of the gob. The oxygen level in the interior of the gob is
critical when dealing with spontaneous combustion. If conditions are
such that the oxygen content in critical areas within a gob cannot be
reduced below that necessary for a methane ignition to occur, a bleeder
system may provide the most safety. MSHA specifically solicited comment
on this subject; however, none was received.
Under paragraph (f)(1), the approved ventilation plans for mines
that have or are susceptible to spontaneous combustion must specify
measures to detect methane, carbon monoxide, and oxygen concentrations
in worked-out areas. These measures must be taken during and after
pillar recovery and in worked-out areas where no pillars have been
recovered. The purpose of these measures is to determine if worked-out
areas will be ventilated or sealed. If the methane concentration or
other hazards in the worked-out area cannot be controlled while the
mine is limiting airflow to avoid spontaneous combustion, it may be
necessary to seal or to ventilate the worked-out area using a bleeder
system. These measures also help to determine the extent to which the
worked-out areas can be ventilated without increasing the spontaneous
combustion hazard.
Under the provisions of paragraph (f)(2) the operator is required
to specify in the mine ventilation plan the actions that will be taken
to protect miners from the hazards of spontaneous combustion.
Protections from the hazards of spontaneous combustion might include:
Additional continuous monitoring of fire gases at strategic locations
underground, increased air sample collection and analysis, trending of
air contaminant data, increased examinations, and changes to the mine
ventilation system such as redistribution of air or pressure balancing.
This requirement would be triggered if the mine has a demonstrated
history of spontaneous combustion, or, if an evaluation of the
susceptibility of the coal seam to spontaneous combustion leads to a
mine operator determination that a bleeder system should not be used.
One commenter stated that this rule is unnecessary because only a
limited number of mines actually have a demonstrated spontaneous
combustion problem. The commenter suggested that the petition for
modification (variance) process should be used to address this issue,
which would allow miners representatives to participate. The final rule
does not adopt this approach. To the extent practicable, an objective
of this rulemaking is to reduce the need for exceptions and paperwork.
In this case, the existing mine ventilation plan process provides a
ready-made mechanism for establishing the precautions necessary, on a
mine-by-mine basis, to protect miners from the hazards of spontaneous
combustion in a timely manner. In addition, under the final rule,
miners representatives are afforded input into the mine ventilation
plan.
Another commenter stated that paragraph (f) should be directed more
to the detection and control of spontaneous combustion and not solely
at its prevention. The commenter offered examples of detection and
control techniques that could be used.
MSHA agrees that spontaneous combustion prevention, detection and
control are all important when dealing with spontaneous combustion. The
final rule recognizes, however, that while prevention is the goal,
instances of spontaneous combustion will occur.
Another commenter stated that the preamble to the proposal was not
correct in that it implied a need to limit airflow to avoid spontaneous
combustion. The commenter states that, to avoid spontaneous combustion,
miners must create a near-zero pressure differential across most areas
of concern. MSHA agrees that creating a ``near-zero pressure
differential'' will have the desired effect of limiting the airflow. In
a paper entitled ``Examination of Bleederless Ventilation Practices for
Spontaneous Combustion Control in U. S. Coal Mines'' presented at the
7th U.S. Mine Ventilation Symposium in June 1995, the authors report
that their study revealed that restricting airflow into mined-out areas
is recognized world-wide as a spontaneous combustion control measure
and that when designing a bleederless ventilation system critical
attention must be given to mine layout, seal construction, methane
drainage, regulations, monitoring, and emergency procedures. In
discussing the subject of air leakage, Koenning in a paper entitled
``Spontaneous Combustion in Coal
[[Page 9786]]
Mines'' presented at the 4th U.S. Mine Ventilation Symposium in June
1989, identified air leakage as the most often cited cause of
spontaneous combustion. In both of these papers, the authors emphasize
the need to properly design a bleederless ventilation system to reduce
the likelihood of spontaneous combustion and achieve the level of
worker safety desired. MSHA agrees with these authors that a
bleederless ventilation system must be designed to encompass all of the
factors identified. It was suggested by one commenter that measurement
of carbon dioxide should be included in the requirements of paragraph
(f). In discussing the gases required to be measured (methane, oxygen,
and carbon monoxide), the commenter stated that these gases alone will
not aid in the detection of spontaneous combustion in its incipient or
developed stage. The commenter suggested that miners be required to
monitor for carbon dioxide because, in the opinion of the commenter,
the trend in the ratio CO/CO2 is the only viable predictor.
MSHA sees merit in the measurement of carbon dioxide as well as
other products of combustion to assist in the detection of spontaneous
combustion. However, the ratio CO/CO2 is not the only viable
predictor of spontaneous combustion. One researcher suggested that
carbon monoxide production is the earliest, detectable effect of
spontaneous heating. Others have suggested, following a series of
tests, that four gas ratios clearly indicated the development of
thermal runaway, but only the CO2- O2 ratio gave an
early warning of the heating in the coalbed.
As can be seen, a number of methods of predicting the onset of
spontaneous combustion have been suggested. While paragraph (f)(1)
requires only the measurement of methane, oxygen, and carbon monoxide,
MSHA would not discourage operators from incorporating, as part of the
mine ventilation plan, any or all of these methods as well as other
appropriate methods to aid in the early detection of spontaneous
combustion.
Section 75.340 Underground Electrical Installations
Electrical installations can provide an ignition source for methane
and can represent a serious fire hazard underground. Typical electrical
installations are battery charging stations, substations, rectifiers
and certain water pumps. Section 75.340 requires that these
installations be ventilated and protected against fire. These
installations must also be housed in noncombustible structures or areas
or protected with fire suppressions systems, and be ventilated or
monitored to protect miners working down stream from the products of
combustion.
MSHA proposed to revise paragraph (a) of existing Sec. 75.340 to
clarify the standard and to add requirements concerning alarms and
sensors. The final rule adopts the language in the proposal with one
modification. It replaces the word ``located'' with the word
``housed.''
Existing 75.340(a) requires that certain underground electrical
equipment be either located in a noncombustible structure or area or
equipped with a fire suppression system. Section 75.340 (a) also
requires that the equipment be ventilated by intake air, and lists
alternatives ways to do so in paragraphs (a)(1),(a)(2), and (a)(3). The
final rule adds language to paragraph (a)(3), the alternative which
establishes an acceptable means for monitoring the underground
electrical installations using sensors other than a Sec. 75.351
atmospheric monitoring system.
MSHA sought in the proposal to clarify the application of existing
Sec. 75.340(a)(3). Paragraph (a)(3) of the existing rule provides for
the activation of doors upon the presence of certain indications of a
possible fire. The paragraph was appropriate for enclosed structures or
areas; but questions at informational meetings challenged its
applicability to the alternative where a fire suppression system was
used without an enclosure. To address the questions, the proposal
placed the requirements for noncombustible structures or areas and for
fire suppression systems into separate paragraphs. MSHA proposed that
one of the alternatives for ventilating with intake air (monitoring the
underground electrical installations using sensors other than a
Sec. 75.351 atmospheric monitoring system) was acceptable only if the
equipment was located in a noncombustible structure or area and not
acceptable if only a fire suppression system was used. This revision
eliminates the confusion that existed with the existing rule. It should
be noted that if an operator elects to locate this equipment in a
noncombustible structure or area, the operator would not be precluded
from also installing a fire suppression system.
One commenter questioned the reason for separating fire suppression
and noncombustible structures, noting that there was no need for the
distinction in the rule. In objecting to the proposal, the commenter
stated that there should be several cumulative layers of protection,
including both fireproof enclosures and fire suppression systems. The
commenter includes several examples of fires involving compressors to
illustrate this point. MSHA has addressed concerns relative to
compressor fires in the final rule section dealing with compressors,
Sec. 75.344. Other examples cited by the commenter included explosions
caused by mobile equipment and a fire that occurred on a power center
located at the working section. The instances cited by the commenter
are not relevant to Sec. 75.340. The commenter argued that fire
suppression systems have not worked and uses the compressor fires
previously mentioned to illustrate the point. MSHA notes that there are
numerous instances where the systems have worked. However, in the vast
majority of these cases there is no documentation because there is no
requirement for reporting fires that are extinguished within 30
minutes.
The final rule in paragraph (a)(1)(iii) revises existing paragraph
(a)(3) of Sec. 75.340 by adding 2 requirements. It adds a requirement
that a visual and audible alarm be provided on installations if the
(a)(1)(iii) alternative is selected. Also, when operating under this
alternative, monitoring of intake air that ventilates battery charging
stations must be done with sensors not affected by hydrogen.
Some commenters noted their agreement with these proposed changes.
Noting that no single system is failsafe, one commenter suggested that
all the requirements of Sec. 75.340 be combined and made applicable in
all cases. The requirements would include; noncombustible structures,
fire suppression, ventilation directly to the return, additional
communications, continuous AMS monitoring for carbon monoxide, methane,
and hydrogen, along with automatic closing doors and temperature
protection. After consideration of the comments and the underlying
rationale, MSHA concludes that to require that the alternatives be
applied cumulatively in every case would be infeasible or impractical.
In addition, MSHA does not believe that these overly restrictive
requirements are necessary in all circumstances.
Paragraph (a)(1)(iii) addresses electrical installations that are
equipped with doors that automatically close when sensor readings reach
certain levels. One of these action levels is a level for the optical
density of smoke. In Sec. 75.340 (a)(1)(iii)(B) of the proposal and the
preamble discussion on page 26371, MSHA refers to the optical density
of smoke of 0.05 per meter to characterize the sensitivity of smoke
detectors. As discussed in MSHA's opening statement to the ventilation
rulemaking hearings,
[[Page 9787]]
the value used for the optical density of smoke is based on information
provided from the Bureau of Mines. MSHA pointed out that based on
comments received from the Bureau of Mines, this number is incorrect
and should be divided by 2.303 to conform to the internationally
accepted term of optical density. No commenter took issue with this
point. MSHA has made the correction in the final rule. One commenter
suggested that optical densities be increased and based on an ambient
to account for background dust. In contrast, another commenter
suggested that the specified optical density should be reduced by half.
MSHA has found insufficient justification to adopt either of these
suggestions and believes that the specified 0.05, corrected to 0.022
based on comments from the Bureau of Mines, is the appropriate level
for optical density used in Sec. 75.340. Existing Sec. 75.351
Atmospheric monitoring system (AMS), uses a level for optical density
of smoke of 0.05 per meter. MSHA recognizes that the level in
Sec. 75.351 should also be corrected. MSHA intends to correct the level
for optical density used in Sec. 75.351 in a future rulemaking. In the
meantime, MSHA will use an optical density of 0.022 per meter for
purposes of Sec. 75.340.
The visual and audible alarm required in paragraph (a)(1)(iii) must
be situated so that it can be seen or heard by persons traveling in the
intake entry immediately adjacent to the installation. It was suggested
to MSHA that these electrical installations may be susceptible to fire
and the fire could go undetected. The visual and audible alarms would
provide additional safety at these installations by alerting miners in
the area.
One commenter suggested that an alternative should be added to
carbon monoxide or smoke detection. The suggested alternative would be
to permit another means that would be approved by the district manager.
This suggestion has not been adopted since both carbon monoxide
monitoring and smoke detection have been shown to be effective and
reliable and can be used.
One commenter stated that battery chargers located on working
sections do not present the same hazards as those located outby, along
the intake. The commenter suggested that chargers located on working
sections should be exempted from Sec. 75.340. MSHA disagrees. MSHA
believes that battery chargers present the same safety hazards
associated with other electrical equipment plus the charging of
batteries results in the liberation of hydrogen. There is a
demonstrated history of fires caused by battery chargers. The
requirements are necessary to safely operate chargers, regardless of
the location of the charger.
One commenter suggested that all water pumps should be exempted
from Sec. 75.340 because fire history is limited. The standard already
exempts pumps that have limited fire hazard potential in paragraphs
(b)(2) through (b)(6). Pumps outside of the listed categories do
present hazards. As an example, a 200 horsepower pump exploded at a
mine in Virginia after an extended period of being overheated. An
example of a pump posing a limited hazard is an emulsion pump located
at or near the section that is moved as the section advances or
retreats. Emulsion pumps are considered for the purpose of Sec. 75.340
to be water pumps.
Also, one commenter called attention to MSHA's omission of the word
``or'' in two places in Sec. 75.340, Underground Electrical
Installations. MSHA agrees that the omission was inadvertent and so
stated in its opening statement at the ventilation hearings. In
Sec. 75.340, the word ``or'' has been inserted between paragraphs
(a)(1) (i) and (ii) dealing with alternative ventilation requirements
for noncombustible structures or areas and between paragraphs
(a)(1)(iii) (A) and (B) setting out criteria that would govern the
activation of automatic closing doors.
Another commenter suggested that the signal from the visual and
audible alarms required by existing paragraph (a)(3) should be sent to
a surface location at the mine rather than being located outside the
installation. The commenter supported the suggestion by indicating that
a quicker response would thus be provided since the alarm would be
immediately noticed. In order to achieve an effective level of safety,
MSHA has provided in paragraph (a)(1)(iii) that the visual and audible
alarm be located outside of and on the intake side of the enclosure.
This location will permit persons traveling in the intake entry
immediately adjacent to the installation to see or hear the alarm.
Paragraph (a)(2) allows the use of an alternative system using an AMS
which would provide an alarm at the surface of the mine.
Finally, one commenter objected to the use of the word ``located''
in the phrase ``located in noncombustible structures or areas''. The
commenter argued that MSHA should use the word ``housed'' and that the
use of the word ``located'' actually reduces the protection intended by
Congress. MSHA does not agree with that interpretation and maintains
that in the context in which the word is used there is no meaningful
distinction between the two words. However, because the word suggested
by the commenter will not reduce safety and may add to the clarity of
the rule for some readers, it has been adopted in the final rule.
Section 75.342 Methane Monitors
Methane monitors are a critical link in the safety protections
designed to prevent mine explosions. Mounted on mining equipment which
works directly in the face, these instruments provide the first warning
that gas is being liberated in potentially dangerous quantities.
Methane monitors are relied upon to shut down mining equipment
automatically when gas concentrations reach 2 percent. The continued
operation of mining equipment under these conditions can lead to a
spark and catastrophic explosion.
The final rule revises paragraph (a)(4) which addresses maintenance
and calibration of methane monitors that are required on underground
mining equipment to provide a warning to equipment operators when the
methane concentrations nears dangerous levels. Methane monitors also
automatically deenergize the equipment when methane approaches the
explosive range or if the monitor is not operating properly. The rule
requires that trained persons perform maintenance and calibration of
the methane monitors at least every 31 days and requires that
calibration records be maintained. The final rule does not adopt the
proposal which would have required that a written maintenance program
be available for inspection.
Some commenters expressed the view that the proposed revisions were
unnecessary and recommended that they be deleted from the final rule.
Other commenters supported the proposed revisions and urged MSHA to
adopt additional requirements as well.
Paragraph (a)(4) of the final rule requires that calibration and
maintenance of the monitors be performed by persons properly trained in
maintenance, calibration, and permissibility of the methane monitors.
One commenter expressed the view that no change was needed to the
existing rule. However, the rulemaking record also contains a number of
examples in which poorly maintained or improperly repaired methane
monitors have been found during the investigations of methane related
accidents.
The final rule in paragraph (a)(4)(ii) requires that each operator
maintain a record of all calibration tests of methane monitors. As with
other recordkeeping requirements under the final rule, records must be
maintained in a secure
[[Page 9788]]
book that is not susceptible to alteration, or may be kept
electronically in a computer system so as to be secure and not
susceptible to alteration. Some commenters recommended that a record be
kept of all maintenance performed on a methane monitor, urging that a
record is necessary to prove the maintenance is done. MSHA believes
that the revisions contained in the final rule, together with the
existing requirements, will assure an appropriate level of maintenance
without the need for additional records of maintenance.
Some commenters expressed concern over the security of computer-
based records, and offered examples of breaches of security in the
banking and national security fields. Others, however, advocated the
use of computers for the storage and retrieval of records as being
highly accurate, requiring less storage space and facilitating data
retrieval. MSHA agrees that security of required records is important.
It is also MSHA's objective to make the final rule requirements for
compilation and storage of records practical and in concert with modern
methods. To this end, the final rule requires that the record of
maintenance and calibration of methane monitors be maintained in secure
books that are not susceptible to alteration, and also permits these
records to be maintained electronically in a computer system so as to
be secure and not susceptible to alteration. The calibration record
will aid operators in tracking calibration activity and will serve as a
check to assure that calibrations are being conducted at least once
every 31 days. The record will also be reviewed by authorized
representatives of the Secretary and miners' representatives to
determine that calibrations are being conducted as required.
Paragraph (a)(4)(iii) of the final rule requires that operators
retain the record of calibration tests for 1 year from the date of the
test. Records are to be maintained at a surface location at the mine
and made available for inspection by authorized representatives of the
Secretary and the representative of miners. A discussion of comments
concerning the use of computers to maintain records can be found in the
General Discussion of this preamble.
Several commenters suggested that equipment not operated in the
face area also be equipped with methane monitors. Commenters noted
accidents which have occurred when this nonpermissible equipment has
ignited methane in outby areas. Commenters also asserted that equipment
used for the withdrawal of personnel during fan stoppages would be
safer if methane monitors were provided. An opposing comment indicated
that an expansion of the methane monitor coverage was not necessary
since methane is rarely associated with outby areas. Because of the
response time of methane monitors, and considering the speed at which
most outby equipment normally operates, it is unlikely that a monitor
would prevent a machine from entering a body of methane if such a
concentration were encountered. MSHA believes that methane monitors are
suitable and effective in face areas where coal is being cut, mined, or
loaded. However, MSHA does not believe that an expansion of coverage to
include all nonpermissible equipment is warranted.
A number of commenters recommended that methane monitors should be
calibrated at least every 7 days rather than at least every 31 days as
provided by the existing standard. One commenter suggested daily
calibration. Commenters noted that methane monitors lose sensitivity
and that response time increases with monitor age and after exposures
to elevated methane concentrations. The existing requirement for
calibration of methane monitors at least every 31 days parallels the
recommendations of several manufacturers. The 31 day requirement
establishes a maximum time interval between calibrations. However, the
final rule also requires the operator to maintain methane monitors in
permissible and proper operating condition. Thus, under unusual
circumstances of use, it is possible that weekly or even more frequent
calibration may be necessary to comply with the standard.
Comment was also received recommending an additional requirement
that calibration records be countersigned by the Maintenance Supervisor
or Chief Electrician at the mine. The final rule does not adopt this
recommendation. The purpose of the calibration record required under
the final rule is not the same as other records where countersigning is
required by the final rule. Countersigning requirements are directed at
informing upper mine management of hazardous conditions which require
their attention. While the calibration record has the potential to
assist mine management in identifying equipment problems, its main
function is to assist operators in assuring that timely calibration is
occurring.
The proposal would have required that operators adopt a written
maintenance program for methane monitors. Commenters pointed out that
the existing standard already requires all permissible equipment,
including methane monitors, to be maintained in permissible condition.
MSHA agrees.
Section 75.344 Compressors
Section 75.344 deals with the use of air compressors underground.
As discussed in the introductory section of this preamble, MSHA stayed
Sec. 75.344(a) because of a concern over a possible overheating or fire
hazard. Improperly used or maintained air compressors can present a
significant risk of fire underground. MSHA determined that the cause of
the 1984 fire at the Wilberg Mine that claimed the lives of 27 miners
was an improperly maintained compressor. In general, Sec. 75.344
requires that most compressors be operated only while attended or
located in a noncombustible structure or area that is monitored for
temperature and carbon monoxide or smoke; have a fire suppression
system; and, automatically shut down in the event of a fire.
The final rule revises the existing Sec. 75.344, including the
stayed paragraph (a), and supersedes interim Sec. 75.345. The final
rule recognizes that in some cases compliance with the existing rule
could result in heat buildup when a compressor is located in a
noncombustible structure or area. To address this possible hazard the
final rule provides an option. A compressor would be acceptable when
not located in a noncombustible structure or area provided it is
continuously attended by someone who can see the compressor at all
times, activate the fire suppression system and shut off the
compressor. Also, the existing rule is modified for compressors that
are located in a noncombustible structure or area. They must be
ventilated by intake air coursed directly into a return air course or
to the surface and equipped with sensors to monitor for heat and for
carbon monoxide or smoke. In addition, upon the activation of the fire
suppression system, the compressor must automatically deenergize or
shut off.
The final rule does not include proposed paragraph (b)(2) which
provided an additional alternative means of ventilating compressor
installations located away from working sections and near a return air
course where a substantial pressure differential exists.
Comments were solicited on the exemption for compressors having a
certain maximum horsepower. Comments were received both supporting and
opposing a possible revision to increase the limit from 5 to 30
horsepower. Because of the history of compressor fires, including the
1984 Wilberg mine disaster which resulted in
[[Page 9789]]
27 fatalities, the existing limitation of 5 horsepower has not been
revised. One commenter questioned the proposal reference to 9 mine
fires which started in compressors between 1970 and 1992. The commenter
suggested that the nine fires was inaccurately low and referenced an
MSHA report which stated that 21 compressor fires occurred between 1977
and 1987. The preamble discussion addressing the number of fires was in
relation to underground coal mines. Other compressor fires have
occurred at surface coal mines and at noncoal mines. Regardless of the
number of compressors affected, however, the safety concerns remain the
same.
Several commenters suggested that the cutoff for application of
Sec. 75.344 be changed from 5 horsepower for all compressors to 30
horsepower for reciprocating compressors and 5 horsepower for all other
types of compressors. The rationale for this recommendation was that
reciprocating compressors of up to 30 horsepower contain about the same
amount of lubricating oil as 5 horsepower compressors. This suggestion
was not included in the proposal, based on MSHA information (Report No.
06-292-87 of the Industrial Safety Division, Pittsburgh Safety and
Health Technology Center) that the predominant hazard for fire or
explosion in reciprocating compressors is not the lubricating oil, but
rather the formation of carbonaceous deposits in the discharge system.
MSHA received comments addressing the formation of carbonaceous
deposits in the discharge system indicating that the use of synthetic
oil prevents any carbonaceous accumulation. Commenters suggested that
all identified hazards would be eliminated through the use of synthetic
oils. However, commenters also noted that synthetic oils have a higher
flash point.
MSHA has examined the subject of synthetic oils and found that
synthetic oils can be formulated with polyalphaolefins, polyglycols,
silicones, esters, phosphate-esters, and di-esters as the primary
ingredient. These compounds are also blended with mineral oils to form
synthetic lubricants. The rate of oxidation is varied among these
compounds. Of these types, only silicone based lubricants exhibit
virtually no oxidation and are used primarily where extremely high
temperatures are expected. Also, silicone based lubricants are
inherently fire resistant. Unfortunately, silicone based lubricants are
incompatible with reciprocating compressors and will rapidly lead to
failure of the compressor. Polyalphaolefins, polyglycols, and mineral
oil blends all contain hydrocarbons and have a tendency to varnish and
create deposits in air compressors. Accordingly, the final rule, like
the existing rule, exempts compressors of five horsepower or less and
the suggested revision to 30 horsepower has not been adopted.
One commenter stated that modern compressor technologies allow for
much safer rotary screw compressor operation using non-defeatable
programmed safety controls, synthetic lubricants, automatic fire
suppression and shutdown, and other precautions. Although synthetic
lubricants offer some safety enhancement, they do not fully mitigate
the hazards. Also, considering the accident history including the
Wilberg disaster, MSHA has not provided an exemption for rotary screw
compressors.
Existing Sec. 75.344 (a)(1) requires all compressors to be located
in noncombustible structures or areas and to be equipped with a heat-
activated fire suppression system. During informational meetings it was
brought to MSHA's attention that in some instances requiring
compressors to be inside such a structure could present a hazard
through compressor overheating. Upon reviewing this potential effect of
the regulation, MSHA agreed. Therefore, before the existing standard
could become effective, MSHA stayed the application of paragraph (a)(1)
and included the standard in this rulemaking.
The final rule addresses the potential of compressor overheating by
allowing a compliance alternative to enclosing the compressor. Heat is
generated at considerable rates by operating compressors. Improperly
used or maintained compressors can present a significant risk of fire.
To minimize this hazard, the rule specifies other installation and
operational requirements as well as providing for fire detection and
fire suppression. As recommended by commenters, the final rule also
provides for audible and visual alarms and automatic deenergization or
shut-off.
Several commenters discussed the proposed revisions to paragraph
(a). One commenter urged that the term ``operation'' be clarified,
noting that compressors which are designed to automatically start when
necessary to rebuild air pressure should be protected. MSHA considers
compressors that are installed to automatically start when necessary to
rebuild air pressure to be in operation. MSHA agrees that these
compressors should be provided either a noncombustible structure (or
area) or an attendant. Accordingly, for the purpose of clarifying the
requirement, the final rule includes the commenter's recommendations.
Compressors which have been disconnected from the power or fuel source
would not be subject to the requirement under the final rule.
Another commenter suggested that the person specified in paragraph
(a)(1) be trained. The commenter noted that the attendant would be of
little value if unaware of the appropriate response to a fire. The
commenter suggested that the person know how to deenergize the machine
and activate the fire suppression system manually. MSHA agrees and
notes that this knowledge is required under the proposal by requiring
that the attendant be capable of performing these tasks. MSHA believes
that any training necessary to meet this capability is implicit in the
standard and the proposal has been retained under the final rule.
Another commenter suggested that an attendant be accepted as an
alternative to noncombustible structures or areas for a maximum of 8
hours. The commenter stated that 8 hours would provide sufficient time
for urgent roof bolting or construction work such as coating stoppings
or powering a jack hammer. After considering the comment, the suggested
time limit has not been adopted. MSHA believes that a continuous
attendant, always within sight of the compressor and capable of
responding as required, provides a level of protection equivalent to
the protection provided by an enclosure. Therefore, the final rule
allows either alternative to be selected. It should also be noted that
the final rule has been revised to require either a continuous
attendant or containment in a noncombustible enclosure or area.
One commenter suggested that an alternative be provided in the rule
to allow for video monitoring of compressors as an alternative to
attendance or noncombustible enclosures. MSHA has not adopted the
suggestion since video monitoring would not provide an equivalent level
of safety compared to either an enclosure or attendance. There would be
a considerable time delay in responding to a video monitor as compared
to a nearby attendant who could immediately shut down the compressor,
activate fire suppression, discharge fire extinguishers, apply rock
dust, and take other necessary actions.
Other commenters addressed an allowable distance within which the
compressor attendant must remain. In the preamble to the proposal, MSHA
solicited comments on the proposed language, ``can see the compressor
at all times'' versus having the attendant
[[Page 9790]]
remain within some specified distance. Rationale was solicited for any
specific distances suggested. Several commenters supported the
proposal, noting that adjustment is inherently provided for high mining
heights and seam undulations since a low undulating seam would cause
the attendant to remain closer to the compressor. Another commenter
suggested that a maximum distance of 20 feet be specified. The
commenter reasoned that a maximum distance of 20 feet would assure that
the attendant could react to a fire quickly, noting that a compressor
fire would propagate rapidly. The commenter also voiced a concern over
travel time in low height mines and noted that distances over 20 feet
might allow a fire to get out of control before the attendant could
reach the machine.
Another commenter was concerned with the proposed requirement in
(a)(1) that a person be able to see the compressor at all times. The
commenter suggested that the term ``close proximity'' be adopted noting
that a person could be in close proximity, e.g. in an adjacent
crosscut, but not within sight. The commenter suggested that this
should be acceptable since the person would still be able to activate
the fire suppression system. MSHA disagrees. The suggested situation is
not acceptable since a considerable delay could result before detection
of a problem if the person were not within sight of the compressor. In
such a case the person would be relying on the smell of smoke or some
indirect means of detecting a problem. Because of the potential fire
hazard associated with compressors, reaction time is critical. MSHA
continues to believe that reaction time is appropriately minimized if
the assigned person can see the compressor at all times, is capable of
deenergizing the unit, and is capable of activating the fire
suppression system. While agreeing that reaction time is critical and
after considering all of the comments, MSHA finds the arguments for not
specifying a set distance to be more persuasive. Therefore, the final
rule permits compressors to be continuously attended by a person
designated by the operator who can see the compressor at all times
during its operation. Any designated person attending the compressor
must be capable of activating the fire suppression system and
deenergizing or shutting-off the compressor in the event of a fire.
If a compressor is not enclosed in accordance with (a)(2), the
compressor can be operated only while it can be seen by a person
designated by the operator according to (a)(1). In adopting this
approach, the proposed paragraph (a)(1) language was deleted.
Commenters indicated confusion over the similarity of proposed
paragraphs (a)(1) and (b)(1) of the existing rule. The final rule
combines these two requirements in (a)(1). The final rule requires both
that the person be able to see the compressor and be capable of
activating the fire suppression system.
Paragraph (a)(2) of the final rule requires that compressors, if
installed in a noncombustible structure or area, be ventilated by
intake air coursed directly into a return air course or to the surface
and be equipped with sensors to monitor for heat and for carbon
monoxide or smoke. MSHA expects that an air quantity sufficient to cool
the compressor will be provided through the enclosure. The
manufacturer's operation manuals for compressors often specify an air
quantity or a maximum ambient temperature. The sensors required by
paragraph (a)(2) must deenergize power to the compressor, activate a
visual and audible alarm located outside of and on the intake side of
the enclosure, and activate doors to automatically enclose the
noncombustible structure or area when either of the conditions in
paragraph (a)(2)(i) or (ii) occurs. The visual alarm should be situated
so that it can be seen by persons traveling in the intake entry
immediately adjacent to the enclosure. The sensors must also deenergize
or shut-off the compressor in addition to closing the doors of the
enclosure.
Paragraph (a)(1)(ii) specifies that the sensors shall deenergize
power to the compressor, activate a visual and audible alarm located
outside of and on the intake side of the enclosure, and activate doors
to automatically enclose the noncombustible structure or area when the
carbon monoxide concentration reaches 10 parts per million above the
ambient level for the area, or the optical density of smoke reaches
0.05 per meter. These levels are the same as required by the existing
rule. As discussed in MSHA's opening statement at the ventilation
rulemaking hearings, the value used for the optical density of smoke is
based on information provided from the Bureau of Mines. MSHA pointed
out that, based on comments received from the Bureau of Mines, this
number is incorrect and should be divided by 2.303 to conform to the
internationally accepted term of optical density. MSHA's remarks were
made in reference to the requirement in Sec. 75.340(a)(1)(iii)(B). The
final rule also makes a conforming technical revision to
Sec. 75.344(a)(2)(ii).
Paragraph (e) of the final rule requires automatic deenergization
or automatic shut off of the compressor if the fire suppression system
of paragraph (b) is activated. A number of commenters suggested that
compressors should have an automatic shutdown feature that deenergizes
or shuts-off the compressor when the required fire suppression system
is activated. MSHA agrees. MSHA recognizes that under Sec. 75.1107-4
automatic deenergization is required if the automatic fire suppression
system is activated on unattended electrically powered compressors.
Proposed paragraph (b)(2) has been omitted from the final rule. The
paragraph was intended to provide additional flexibility for compressor
installations located away from working sections and near a return air
course where a substantial pressure differential exists. No comments
were received in support of the proposed standard, while a number of
comments were received in opposition. Commenters objecting to the
standard raised concerns about overheating and stated that the
revisions were made unnecessary in view of modified paragraph (a). MSHA
agrees. Historically, when compressors that are on fire continue to
operate, they often released oil into the environment, thus increasing
the severity of the fire. For this reason, MSHA believes that safety is
best served by requiring compressors to be deenergized or shut-off when
the fire suppression system is activated. Commenters recommended
deenergization in (a)(2) of the final rule. MSHA agrees and has the
included automatic deenergization in (a)(2). One commenter suggested
that alarms be automatically given at the section and surface and that
two-way communications be provided at each compressor installation.
This recommendation has not been adopted since the rule provides the
desired level of safety through venting to the return, automatic fire
extinguishment and closure of doors, in addition to the alarms outside
the enclosure.
Section 75.360 Preshift Examination
The preshift examination is a critically important and fundamental
safety practice in the industry. It is a primary means of determining
the effectiveness of the mine's ventilation system and of detecting
developing hazards, such as methane accumulations, water accumulations,
and bad roof.
A considerable number of comments were received representing a
range of opinions on the changes MSHA proposed. After consideration of
all comments received, the final rule
[[Page 9791]]
adopts certain modifications and clarifications to the existing
standard to increase the effectiveness of the preshift examination. The
final rule removes paragraph (e), redesignates existing paragraphs (f)
through (h) as (e) through (g), revises paragraphs (a), (b), and (f)
and adds new paragraphs (b)(8) through (b)(10).
Existing paragraph (a) is divided into paragraphs (a)(1)and (a)(2)
in the final rule. Paragraph (a)(1) of the final rule contains the
existing general requirement that preshift examinations are to be
conducted by certified persons designated by the operator. Paragraph
(a)(1) also modifies the existing and proposed language in response to
comments, to provide for preshift examinations at 8-hour periods.
Paragraph (a)(2) of the proposed rule would have allowed pumpers to
conduct an examination in lieu of the preshift examination under
certain conditions. The final rule adopts this approach with 2 changes.
The final rule does not require the pumper to examine for noncompliance
with mandatory safety and health standards that could result in a
hazardous condition and does require that records be made and retained
in accordance with Sec. 75.363.
A number of commenters addressed the application of this standard
at mines where extended, overlapping, or other novel working shifts are
employed. MSHA agrees with commenters that evolution within the
industry in shift scheduling has presented a number of questions and
controversies regarding the standard which must be resolved to assure
that proper preshift examinations are conducted within suitable time
frames. Based on comments, the final rule adopts a modification to
clarify and standardize the application of the preshift examination in
recognition of the use of novel shifts while maintaining the protection
of the existing standard.
Underground working schedules of three 8-hour shifts per day were
virtually standard when the previous rule was implemented. Currently a
substantial number of mining operations have work shifts of more than 8
hours. Other operations stagger or overlap shifts providing for
continuous underground mining activities. Some mines that operate
around the clock schedule persons to begin shifts at one-or two-hour
intervals. In such cases, controversies and misunderstandings have
developed regarding application of the current standard.
Commenters suggested that preshift examinations should be conducted
for distinct 8-hour periods. Under this scenario a preshift examination
for an 8-hour period would be acceptable for the entire 8-hour period
regardless of shift schedules. Other comments indicate that this
suggested modification would be consistent with the original intent and
language of section 303(d)(2) of the Mine Act, which provides that no
person, other than certified persons designated to conduct the
examination, is permitted to enter any underground area unless a
preshift examination of such area has been made within 8 hours prior to
their entering the area. A commenter stated that to allow preshifts at
more than 8-hour periods reduces the protection envisioned by the
drafters of the Mine Act. MSHA understands the concerns and the
critical nature of the preshift examinations to monitor the constantly
changing conditions underground and has revised the rule accordingly to
provide for an examination at 8-hour intervals.
Under the final rule, operators will establish the 8-hour periods
for which preshift examinations will be conducted. Persons may enter or
leave the mine, regardless of their shift schedule during any
established period for which a preshift examination has been conducted.
However, another preshift examination must be completed prior to the
next 8-hour period if any persons, other than examiners, remain in the
mine. As always, no person other than examiners may enter any
underground area prior to the completion of a preshift examination.
The final rule requires three preshift examinations where persons
are underground for more than 16 hours per day. At mines with only one
8-hour shift per day only one preshift examination per day would be
required. Mines working 10-or 12- hour shifts would conduct preshift
examinations for each 8-hour period during which persons are
underground. MSHA agrees with comments that the original legislation of
the Mine Act envisioned that preshift examinations would be conducted
for each 8-hour interval that persons worked underground. Similar to
the existing requirement, the final rule does not require examinations
for designated 8-hour periods when no one goes underground.
MSHA recognizes that the final rule may cause a limited number of
mines to perform examinations that are not currently required. These
affected mines do not operate 24 hours per day but work one or two
shifts which exceed 8 hours. For example, the final rule requires two
examinations per day at a mine operating one 12-hour shift per day.
When a mine operates two 10-hour shifts per day the final rule requires
three examinations per day. The Agency has concluded that, considering
the speed at which underground conditions can change, a reasonable
period must be identified after which another examination is necessary.
It is not MSHA's intent that the preshift be a continuous examination
without a beginning or an end. Rather if the mine uses regular shifts
that are longer than 8 hours in length, the preshift examination is
good for an entire 8-hour interval. Those persons who start their work
shift later than the normal shift start time do not need an additional
preshift examination during the remainder of the 8-hour period.
However, a preshift will be required if they are to stay in the area
past the end of the 8-hour period. However, in accordance with
longstanding practice, unplanned short excursions past the 8-hour
period that occur infrequently will be accepted without an additional
preshift. For example, miners required to stay an additional short
period of time, such as 15 minutes to complete a mechanical repair, or
due to a mantrip delay, would not need an additional preshift. The rule
simplifies and clarifies the application of the standard at mines
employing creative shift scheduling.
Comments were received suggesting that the regulation should
stipulate 12:00 a.m., 8:00 a.m., and 4:00 p.m. as the beginning of the
8-hour periods for which preshift examinations would be required. This
suggestion has not been adopted. There is no safety or health benefit
to be gained through prohibiting operators from adopting other 8-hour
intervals, e.g., 10:00 p.m., 6:00 a.m., and 2:00 p.m. Also, the
standard is not intended to prevent operators from establishing their
own work times. For example, an operator may elect a starting time of
11:00 a.m. for a weekend project provided the preshift is completed
within the 3 hours prior to the beginning of the shift.
A commenter suggested that the final rule not require a preshift
examination for non-coal producing shifts, where persons are to work in
the shaft, slope, drift, or on the immediate shaft or slope bottom
area. Under the commenter's suggestion, only that area immediately
surrounding the bottom would need to be examined. The rationale given
for the suggested change is that it is intended to bring the standard
into conformity with ``certain state regulatory programs''. MSHA is not
aware of state regulatory programs which would necessitate a change in
the language of the final rule. Additionally, because areas where
persons are not scheduled to work or travel are not required to be
examined under the final rule, the
[[Page 9792]]
change is unnecessary. Therefore, the suggestion of the commenter has
not been adopted.
Paragraph (a)(2) of the final rule provides that preshift
examinations of areas where pumpers are scheduled to work or travel are
not required prior to the pumper entering the areas, if the pumper is a
certified person and the pumper conducts the specified examinations.
This standard recognizes that pumpers travel to remote areas of the
mine to check on water levels and the status of pumps, making regular
preshift examinations impractical. The examinations required by pumpers
include an examination for hazardous conditions, tests for methane and
oxygen deficiency, and a determination of whether the air is moving in
its proper direction in the area where the pumper works or travels. The
examination of the area must be completed before the pumper performs
any other work. A record of all hazardous conditions found by the
pumper must be made and retained in accordance with Sec. 75.363.
One commenter objected to the proposal stating that areas where
pumpers work or travel should be preshift examined. The commenter
stated that the proposed revision would weaken the protections provided
under the existing standard, and that the rule would indirectly require
that pumpers be certified. The commenter noted that most pumpers are
not certified to perform examinations, and that it would be
inappropriate to require ``hourly employees'' to obtain such
certifications. The commenter further suggested that the proposed
revision could infringe on the traditional relationship between labor
and management wherein only management is required to be certified. The
final rule does not require that pumpers be certified. Rather the final
rule provides an option for pumpers to perform examinations for
themselves if they are certified. Otherwise, areas where pumpers are
scheduled to travel must be preshift examined by a certified person.
The final rule maintains the existing level of safety. A complete
examination by a certified person is still required and the examination
will be conducted closer to the time that work is performed in the
area. As with other examination requirements, no one may accompany the
pumper during the examination. It is important to note that the
examination performed by the pumper under paragraph (a)(2) is not
acceptable if other persons have been scheduled to enter the area. The
pumper may only perform an examination in lieu of a preshift for
himself or herself. If, however, after the beginning of the preshift
examination, persons are assigned to enter the area, the pumper may
perform a supplemental examination for other persons in accordance with
Sec. 75.361, provided that the certified pumper is designated by the
operator to conduct such examinations.
Commenters asserted that pumpers cannot conduct quality
examinations and effectively perform their normal work duties. Under a
previous standard replaced in 1992, persons such as pumpers, who were
required to enter idle or abandoned areas on a regular basis in the
performance of their duties, and who were trained and qualified, were
authorized to make examinations for methane, oxygen deficiency and
other dangerous conditions for themselves. Under the final rule, either
a preshift examination must be made in accordance with paragraph (a)(1)
before a pumper enters an area, or certified pumpers must conduct an
examination under paragraph (a)(2).
One commenter cited a 1984 incident at the Greenwich No. 1 mine
where three miners were killed in an explosion while entering an idle
area to work on a pump. The commenter suggested that an effective
preshift examination would have prevented the accident and suggests
that both a preshift examination and examinations by qualified pumpers
should be required. An adequate preshift examination or supplemental
examination as specified in the final rule, would prevent a similar
result. One of these two examinations is always required under the
final rule before persons enter any such idle area.
Also in addressing paragraph (a)(2), one commenter suggested that
some certified persons who are pumpers may not conduct adequate
examinations. According to the commenter, certified persons conducting
examinations under paragraph (a)(2) cannot be expected to perform at
the same level as preshift examiners conducting examinations under
(a)(1). MSHA expects that all certified persons who are required to
conduct examinations, including certified pumpers, will conduct the
examinations in accordance with the standards.
Another commenter suggested that persons performing other jobs,
such as rock dusters, should be permitted to perform examinations for
themselves. Pumpers, unlike most other miners except mine examiners,
travel in remote areas of the mine and normally work alone. Persons
performing work such as rock dusting, however, normally work in newer
areas of the mine where mining has only recently been completed and
normally work as a part of a crew. Therefore, MSHA does not consider
the work assignments to be similar enough to merit the same
consideration and has not included this recommendation in the final
rule.
As proposed, paragraph (a)(2) would have required that the
certified pumper examine for noncompliance with mandatory safety or
health standards that could result in a hazardous condition, test for
methane and oxygen deficiency, and determine if the air is moving in
its proper direction in the area to be worked or traveled by the
pumper. A number of commenters recommended the deletion of the
requirement that the certified pumper identify and record noncompliance
with mandatory safety and health standards that could result in a
hazardous condition. Commenters cited a number of objections: the
requirement would detract from miner safety, would significantly and
unnecessarily increase the burden on examiners, would diminish the
quality of the examination, would require excessive judgment and
discretion by the examiners, and require examiners to make predictions.
After considering all submitted comments, MSHA concludes that these
comments have merit and the final rule does not require certified
pumpers to examine for violations of mandatory safety and health
standards that could result in a hazardous condition.
Under paragraph (a)(2), a record of all hazardous conditions found
by the pumper must be kept in accordance with Sec. 75.363. One
commenter objected in that all of the records resulting from a preshift
examination would not be required of the pumper, such as the locations
of air and methane measurements and the results of methane tests. The
commenter suggested that the full preshift record should be produced
just as if the examination were done according to paragraph (a)(1). In
the case of the pumper-examined area, the records required under
paragraph (a)(2) will assure that mine management is made aware of any
condition which results in a hazardous condition and will facilitate
corrective actions being taken. It is important to note that the pumper
is conducting an examination in a limited area only for himself or
herself. This is in contrast to the various areas addressed in
paragraph (a)(1), where the examination is in anticipation of one or
many other miners entering these areas usually on a regular basis, all
of whom are relying on the examiner's findings. In these circumstances,
it is important that a record is made which can be
[[Page 9793]]
utilized to spot ongoing problems and trends.
Paragraph (b) of the rule specifies the nature of the preshift
examinations and the locations where a preshift examination is
required. Proposed paragraph (b) would have required that the person
conducting the preshift examination would examine for noncompliance
with mandatory safety or health standards that could result in a
hazardous condition. After considering all submitted comments, the
final rule does not contain this requirement.
A number of commenters recommended the deletion of the requirement
to identify and record noncompliance with mandatory safety and health
standards that could result in a hazardous condition. Various
commenters stated that the proposed requirement: would distract the
examiner from the most important aspects of the preshift examination;
would require predictions; would be an unrealistic expectation; and/or
is designed only to facilitate enforcement actions. Commenters also
suggested that the proposal would result in a shift in the focus of
preshift examination from true hazards to noncompliance.
Other commenters objected that the proposed requirement to examine
for noncompliance with mandatory safety or health standards that could
result in a hazardous condition is so vague that it could detract from
miner safety. One commenter suggested that the examiners would spend
their time performing permissibility checks, torquing roof bolts,
measuring roof bolt spacing, and similar tasks which represent a
significant departure from the examiners traditional duties.
Another commenter expressed the opinion that paragraph (b) should
require that all violations of mandatory safety or health standards be
recorded and it should not be limited to those that could result in
hazardous conditions. Preshift examinations assess the overall safety
conditions in the mine; assure that critical areas are properly
ventilated; assure that the mine is safe to be entered by miners on the
oncoming shift; identify hazards, whether violations or not, for the
protection of miners; and through this identification facilitate
correction of hazardous conditions.
The preshift examination requirements in the final rule are
intended to focus the attention of the examiner in critical areas. This
approach is consistent with the fundamental purpose of preshift
examinations which is to discover conditions that pose a hazard to
miners. MSHA is persuaded that to require examiners to look for
violations that might become a hazard could distract examiners from
their primary duties. The final rule, therefore, does not adopt this
aspect of the proposal.
Paragraph (b)(1) of the final rule adopts the proposal and
clarifies that preshift examinations are to include travelways in
addition to roadways and track haulageways. During informational
meetings, commenters indicated that the terms ``roadways'' and ``track
haulageways'' are associated with areas where mobile powered equipment
is operated. By including the term ``travelways,'' the rule clarifies
that areas where persons are scheduled to travel on foot are to be
included, since hazards may also develop in these areas.
One commenter suggested that the proposal would greatly increase
the area that must be preshift examined, even though the requirement is
limited to only those travelways where miners are scheduled to work or
travel. This commenter suggested that in large mines many more areas
than would actually be used by miners would have to be preshift
examined. The premise of the preshift examination is that all areas
where miners will work or travel be examined for hazards. The final
rule change concerning ``travelways'' is intended only to clarify that,
when miners are scheduled to use these areas, they must be preshift
examined first. The final rule, therefore, does not expand the existing
scope to the preshift examination requirements.
The language of the existing paragraph (b)(1) referring to, ``* * *
other areas where persons are scheduled to work or travel during the
oncoming shift'' is transferred to a new paragraph (b)(10) with
conforming changes, as proposed. MSHA received no comments on moving
this provision to paragraph (b)(10). Commenters did respond to the
phrase in proposed paragraph (b)(1) requiring preshift examinations of
roadways, travelways and track haulageways where persons are ``* * *
scheduled, prior to the beginning of the preshift examination to work
or travel during the oncoming shift.'' The purpose of this proposal,
which is adopted in the final rule with only clarifying changes, is to
permit work and mining personnel to be rescheduled after the start of a
shift. Preshift examinations, by their nature, must be completed before
the start of the shift. Changes in conditions, however, such as a
breakdown of equipment, can alter planned work schedules. To
accommodate these circumstances, the final rule requires mine operators
to design preshift examinations around the best information available
at the time the preshift begins. If changes must be made, Sec. 75.361
specifies that areas not preshift examined be covered by a supplemental
examination performed by certified persons before miners enter the
area.
One commenter objected that was confusing and should be modified.
Other commenters foresaw possible abuses of the flexibility offered by
the rule with some operators performing supplemental rather than
preshift examinations, claiming that assignments were made after the
preshift examination begins. After considering the comments, MSHA has
retained the proposed flexibility to preshift examine areas where
miners are scheduled to work or travel. To require more than this would
be impractical.
Section 75.360(b)(3) of the final rule requires preshift
examinations of working sections and areas where mechanized mining
equipment is being installed or removed if anyone is scheduled to work
on the section or in the area during the oncoming shift. A discussion
of the reproposal of provisions concerning the installation and removal
of mechanized mining equipment is presented in the General Discussion
section of this preamble. As with the existing rule, the examination
includes working places, approaches to worked-out areas, and
ventilation controls on these sections or in these areas. The final
rule, like the proposal, adds a new requirement that the examination
also include a test of the roof, face and rib conditions on these
sections or in these areas.
Proposed changes to paragraph (b)(3) not adopted in the final rule
would have also required preshift examination of sections not scheduled
to operate but capable of producing coal by simply energizing the
equipment on the section. Also, proposed changes to paragraphs (c),
(c)(1), and (c)(3) specifying where air volume measurements were to be
taken on these sections have also not been adopted in the final rule.
The new requirement to test the roof, face and rib conditions is
added because of the importance of this test to the safety of miners.
In newly mined areas, checking roof, face and rib stability is most
important to preventing injuries and death. Comments were received in
support of the revision, citing accidents which might have been
prevented had such tests been adequately performed during preshift
examinations. One commenter, when suggesting new wording for paragraph
(b)(3), indicated that the requirement to test the roof, face and rib
conditions should be deleted but
[[Page 9794]]
did not offer any rationale for the suggested deletion. Another
commenter suggested that the preshift examination should only require a
visual examination of the roof, rather than a physical examination.
Physical examinations of the roof, such as ``sounding,'' have been a
historically accepted method for examiners to test roof competency.
Whenever an examiner has a question as to whether a section of roof is
competent, such a test should be performed.
Comments were mixed on MSHA's proposed revision to include idle
working sections as part of the preshift examination. The proposal is
not retained in the final rule. Some commenters objected to the
proposal as unnecessary, burdensome, or impractical. Commenters
believed that the existing Sec. 75.361 requirement for supplemental
examinations prior to anyone entering into such an area was sufficient.
Commenters also stated that a preshift examination in these areas could
introduce a false sense of security and that the effect would be to
divert preshift examiners from more important duties. One commenter
stated that the proposed requirement would be inconsistent with and
contradictory to the basic concept of preshift examinations. Another
commenter objected to MSHA's statement in the preamble to the proposal
that there is a reasonable likelihood that miners will at some point
during a working shift enter sections that are set up to mine coal.
In support of the proposed requirement to preshift examine idle
sections, one commenter cited explosions at the Red Ash Mine in 1973,
the Scotia Mine in 1976, the P&P Mine in 1977, the Ferrell #17 in 1980,
the Greenwich #1 Mine in 1984, and the 1994 explosion at the Day Branch
No. 9 Mine in Kentucky. As the commenter pointed out, in each of these
accidents miners were sent into an area that had not been preshift
examined. However, none of these accidents were the result of miners
entering areas that would have been covered by the proposal. In each
instance, miners entered an area where mining had ceased, but could not
be resumed by simply energizing equipment. Another common thread in
each of these explosions was the failure of the operator to conduct the
required supplemental examination prior to miners entering the area on
an unscheduled basis.
Paragraph (b)(4) of the final rule requires preshift examinations
to include approaches to worked-out areas along intake air courses and
at the entries used to carry air into worked-out areas if the intake
air passing the approaches is used to ventilate working sections where
anyone is scheduled to work during the oncoming shift. The examination
of the approaches to the worked-out areas is to be made in the intake
air course immediately inby and outby each entry used to carry air into
the worked-out area. The examination of the entries used to carry air
into the worked-out areas is to be at a point immediately inby the
intersection of each entry with the intake air course. The standard is
intended to assure that miners are not exposed to the hazards
associated with ventilating working sections with contaminated air
which has passed through a worked-out area. The requirement is
consistent with the Sec. 75.301 definition of ``return air'' and with
Sec. 75.332 which provides that working sections and other specified
areas must be ventilated with intake air.
Commenters correctly noted that a clarification was needed in the
first sentence of proposed paragraph (b)(4) to indicate that the
examination at the specified points is only required if the intake air
passing the approaches is used to ventilate working sections where
anyone is scheduled to work during the oncoming shift. Commenters
suggested that an examination should not be required if the intake air
is not used to ventilate working sections or if no one is scheduled to
work on the section. This was the result intended by the proposal and
the final rule has been revised accordingly.
One commenter also suggested that the requirement in paragraph
(b)(4) is unnecessary because the safeguards in the approved mine
ventilation plan should prevent an air reversal in a worked-out area in
which this air would enter the intake air course. The commenter offered
the example of a worked-out area connected directly to a bleeder
system. MSHA agrees that when proper safeguards are in place and
operating as intended, air reversals are unlikely. However, roof falls
and other obstructions in the worked-out area or in the bleeder can
cause air reversals, permitting return air to enter the intake and be
transported to the working section. Without a suitable examination,
this condition would go undetected and could lead to disaster. While
not exactly the same, the explosion at the Pyro Mine in 1989, which
resulted in the deaths of 10 miners, was the result of a somewhat
similar set of circumstances. A water blockage in the bleeder entry
that combined with changes to certain ventilation controls led to
methane migrating from the worked-out area onto the longwall face.
MSHA's report of this accident concludes, in part, that changes that
occurred during the mining of the longwall panel and in the bleeder
entries caused a fragile balance of air flows to exist in the
ventilation system that permitted methane to migrate from the gob and
to accumulate near the longwall headgate.
One commenter agreed with the proposal and discussed the need to
assure that miners are not exposed to the hazards associated with
ventilating working sections with return air.
Essentially, the final rule requires that at each applicable
approach, three examinations must be made; immediately inby and outby
the approach in the intake entry and in the approach itself immediately
inby the intersection with the intake entry. Situations exist where
multiple openings along an intake lead into a worked-out area. Under
some conditions intake air enters the upstream openings, passes through
the worked-out area, and then re-enters the intake. The examination
required by paragraph (b)(4) is designed to assure that such a
condition is detected. Also, the examination detects any change in
ventilation entering the worked-out area which may warrant follow-up or
corrective actions to assure that the worked-out area is ventilated.
Paragraph (b)(6) of the final rule adopts the proposal modifying
the existing rule. No comments were received on this aspect of the
proposal. The final rule in paragraph (b)(6)(i) requires preshift
examinations to include entries and rooms developed after November 15,
1992 (the effective date of the existing rule), and developed more than
2 crosscuts off an intake air course without permanent ventilation
controls where intake air passes through or by these entries or rooms
to reach a working section where anyone is scheduled to work during the
oncoming shift. Similarly, under (b)(6)(ii) the examination must
include entries and rooms developed after November 15, 1992, and driven
more than 20 feet off an intake air course without a crosscut and
without permanent ventilation controls where intake air passes through
or by these entries or rooms to reach a working section where anyone is
scheduled to work during the oncoming shift.
Existing paragraph (b)(6) requires that a preshift examination be
made in all entries and rooms driven more than 20 feet off an intake
air course without a crosscut or more than 2 crosscuts off an intake
air course without permanent ventilation controls where intake air
passes through or by these entries or rooms to a working section where
anyone is scheduled to work during the oncoming shift. MSHA proposed
[[Page 9795]]
modifications to existing paragraph (b)(6) based on concerns raised
following publication of the existing rule on May 15, 1992. Commenters
at that time indicated that extensive rehabilitation would be required
at a number of mines to implement the standard in the rooms and entries
described in the rule, causing diminished safety for miners performing
the rehabilitation work. Commenters noted that some areas had been
timbered heavily and cribbed because of adverse roof conditions and
that rehabilitation would unnecessarily expose miners to roof falls and
rib rolls while removing or repositioning roof support. In addition,
roof conditions in some areas would remain hazardous even after
rehabilitation. The commenters also noted that many such areas had been
in existence for many years without incident and that any methane
liberation had long since stopped due to the passage of time. They
noted that some areas cannot be effectively sealed and that the risks
associated with rehabilitation and subsequent physical examinations
would greatly outweigh the safety benefit to be gained. MSHA recognizes
the legitimate concerns raised by the commenters and the final rule
requires preshift examination of entries and rooms developed after
November 15, 1992 and driven more than 20 feet off an intake air course
without a crosscut or more than 2 crosscuts off an intake air course
without permanent ventilation controls where intake air passes through
or by these entries or rooms to a working section where anyone is
scheduled to work during the oncoming shift. MSHA believes, however,
that the conditions addressed by paragraph (b)(6) are the result of
improper mining practices in the past. These mining systems should be
revised in the future to avoid poor conditions, or the areas affected
should be fully and reliably ventilated and be examined. Also, the
final rule applies only to entries and rooms developed after the
effective date of the existing rule. As such, the mining industry was
on notice of the shortcomings of mining practices that left entries and
rooms of the type addressed by the standard.
Paragraph (b)(8) retains the proposal requiring preshift
examinations to include high spots along intake air courses where
methane is likely to accumulate, if equipment may be operated in the
area during the shift. As noted in the proposal, it has long been
recognized that methane can accumulate in high areas with no
indications being detected in the lower portions of the opening. As
mobile equipment passes under these areas or a conveyor belt is put
into operation, the methane is pulled down and mixed with the air in
the entry and may be ignited. The final rule addresses the hazards of
undetected accumulations of methane in high spots by requiring preshift
examinations in such areas in intake air courses if equipment will be
operated in the area during the shift.
Several commenters requested that MSHA clarify the term ``high
spots.'' One commenter stated that many hours would be necessary to
examine every indentation in the roof of a large mine and stated the
belief that the turbulence created by passing equipment would render
harmless any of the small amounts of methane that might possibly
accumulate. Another commenter believed the requirement was unnecessary
because there has never been a problem with methane accumulating in
intakes in quantities sufficient to cause an explosion. One commenter
suggested that the requirement should only be applicable to mines with
a demonstrated history of methane accumulations, noting that although
mines are considered likely to liberate methane, it is not likely that
all mines will accumulate methane in high spots.
Another commenter suggested that preshift examinations should be
required in all high spots in intakes, returns, belt entries, and track
haulage entries. The commenter also objected to limiting the
examination in intakes only to areas where equipment may be operated
during the shift. The commenter observed that methane can accumulate
quickly in high spots and that it is critical to detect the methane
before it creates a danger. The commenter notes several accidents
involving methane accumulations in high spots, including: Meigs No. 31
Mine in 1993 where methane in a roof cavity was ignited by a torch; VP-
5 Mine in 1992 when methane in a cavity was ignited by a torch; Ferrell
No. 17 Mine in 1980 where, according to the commenter, methane may have
accumulated in a cavity in the belt entry roof and may have been
ignited by a trolley powered vehicle; and in the VP-6 in 1982 where
methane in a high spot was ignited by a trolley powered vehicle
traveling through the area. The commenter stated that accumulations of
methane in high spots can be ignited by any number of sources.
A meaningful preshift examination requires that conditions which
can lead to an explosion or ignition be detected and corrected before
miners begin their work. In addition to the accidents cited above
attributed to methane accumulations in high spots, the Itmann No. 3
Mine explosion occurred when a trolley powered vehicle ignited methane
in a high spot, resulting in the death of 5 miners and severe burns to
2 other miners. The phrase ``high spots where methane is likely to
accumulate'' should be understood in the coal mining industry.
Experienced miners, and in particular preshift examiners and certified
persons, can readily recognize a high spot where methane is likely to
accumulate. Also, MSHA for many years has considered preshift
examinations to be inadequate where examinations did not include
methane tests in these areas. An examination of ``every indentation,''
as foreseen by one commenter is not expected nor intended by paragraph
(b)(8), which specifies that preshift examinations be used to identify
methane hazards by testing in the appropriate locations. The final rule
does not adopt the suggestion that methane examinations be based on
mine liberation history since significant methane liberation may begin
or can greatly increase at any time. Also, the potential for a
dangerous accumulation of methane in a high spot is influenced by mine
ventilation, particularly the air velocity in the entry.
One commenter suggested that the rule require tests only in
``unventilated high spots'' along intake air courses. The final rule
does not adopt this approach. The purpose of the preshift examination
is to detect hazards, in this case accumulations of methane. Nominal
ventilation in a high roof cavity may not be sufficient to sweep away
methane and an accumulation could exist. The final rule directs an
examiner's attention to such situations.
Proposed paragraph (b)(9) is modified in the final rule. Paragraph
(b)(9) of the final rule requires preshift examinations at underground
electrical installations referred to in Sec. 75.340(a), except those
water pumps listed in Sec. 75.340(b)(2) through (b)(6), and areas where
compressors subject to Sec. 75.344 are installed if the electrical
installation or compressor is or will be energized during the shift.
The proposal would have exempted all water pumps from the requirements
of paragraph (b)(9).
One commenter objected to the exemption for pumps and recommended
that all pumps be examined pointing out that some pumps are large,
high-horsepower units. The commenter noted a 1994 case in Virginia
where a 200 horsepower pump exploded. Pumps of this type may be in
locations or in applications that would not be examined by pumpers
under paragraph (a)(2). The final rule responds
[[Page 9796]]
to this issue by requiring that all pumps should not be exempted from
the standard. Paragraph (b)(9) requires preshift examinations of all
pumps, except those specified in Sec. 75.340(b)(2) through (b)(6).
Pumps specified in Sec. 75.340(b)(2) through (b)(6) and other pumps
that operate automatically or that otherwise may be energized are
generally in the more remote areas of the mine and are to be examined
weekly in accordance with Sec. 75.364.
Pumps which will be examined by certified pumpers in accordance
with paragraph (a)(2) are not covered by the final rule because of the
limited hazards they pose and because certified pumpers would
themselves conduct examinations of this equipment in accordance with
paragraph (a)(2). Examinations by pumpers at these locations will
assure that methane has not accumulated and that the equipment is not
in a condition to create a fire or ignition source.
A review of the accident history reveals a number of fires in
equipment that, under the final rule, would be subject to preshift
examinations. For example, the compressor that MSHA identified as the
probable cause of the fire in the Wilberg Mine, which killed 28 miners,
would have required a preshift examination under (b)(9) of the final
rule. Additionally, MSHA has identified several fires associated with
rectifiers and transformer installations in the mining industry. One of
these transformer fires was discovered during a preshift examination.
One commenter supported proposed paragraph (b)(9) and noted a
number of ignitions involving trolleys. The commenter also noted that
history demonstrates that other electrical installations present
ignition or fire hazards which should be examined before each shift.
One commenter incorrectly understood proposed paragraph (b)(9) to
not require preshift examinations of areas where compressors subject to
Sec. 75.344 are installed if the compressor is or will be energized
during the shift. The standard does require preshift examinations of
such equipment, which includes all compressors except those which are
components of equipment such as locomotives and rock dusting machines
and are compressors of less than five horsepower.
Paragraph (b)(10) adopts the proposal that preshift examinations
include other areas where work or travel during the oncoming shift is
scheduled prior to the beginning of the preshift examination. This
provision recognizes that work requirements and situations may change
after the preshift examination has begun. Often, once the examination
has started it is not possible to contact the examiners to direct them
to newly identified areas where miners will work. In these cases, a
supplemental examination is required before persons work or travel in
these areas. As discussed in the preamble to the proposal, paragraph
(b)(1) requires preshift examinations of any underground area where
persons are scheduled to work or travel during the oncoming shift.
Under the existing rule, an operator did not have the flexibility to
modify work assignments after the preshift examination had begun,
unless it was possible to contact and redirect the examiners to perform
a preshift examination before the beginning of the shift. Commenters in
general supported the proposal. One commenter, however, while
supporting the change expressed concern that the provision could be
abused. MSHA does not anticipate abuse of the rule and believes it to
be a reasonable approach to assuring that areas where persons work or
travel are examined.
As discussed above, the final rule does not adopt the proposed
revisions to paragraphs (c), (c)(1), and (c)(3) and instead retains the
language of the existing standard. While commenters to proposed
paragraphs (c), (c)(1), and (c)(3) objected to expanding air volume
measurements made during preshift examinations to sections where coal
could be mined by simply energizing the equipment, no comments were
received objecting to retaining the requirement for areas where
equipment is being installed or removed. An in-depth discussion of the
reproposal of provisions concerning the installation and removal of
mechanized mining equipment is presented in the General Discussion
section of this preamble.
Paragraph (f) of the final rule sets out the requirements for
recording and countersigning both the results of the preshift
examination and actions taken to correct hazardous conditions found
during the preshift examination. The final rule adopts the following
proposed revisions to the existing rule: a record of the results of the
preshift examination is required to be made; the results of methane
tests are required to be made in terms of the percentage of methane
found; and a certified person is required to record the actions taken
to correct hazardous conditions found during the preshift examination.
Additionally, paragraph (f) of the proposal would have required
countersigning by both the mine foreman and the superintendent or
equivalent individual to whom the mine foreman reports. The final rule
does not require this second level countersigning. Also, the final rule
allows an official equivalent to a mine foreman to sign the records.
Finally, the final rule allows for secure storage of records in a way
that is not susceptible to alteration and the records can be kept in a
book or in a computer system.
Commenters suggested that the final rule only require the examiner
to record uncorrected hazardous conditions and not those which were
corrected by the end of the shift. Commenters characterized the
reporting of corrected hazardous conditions as unnecessary and
unjustified by the accident history.
MSHA did not adopt the proposal to record corrected defects found
during the fan examination required by Sec. 75.312. MSHA believes,
however, that a record of all hazards found during the preshift
examination, including those corrected, is necessary. The record serves
as a history of the types of conditions that are being experienced in
the mine. When the records are properly completed and reviewed, mine
operators can use them to determine if the same hazardous conditions
are occurring repeatedly and if the corrective action being taken is
effective. Additionally, this record can permit mine management, the
representative of miners, and the representative of the Secretary to
better focus their attention during examinations and inspections. The
safety value of a complete record is illustrated by the 1989 explosion
at Pyro Mining Company's William Station Mine in which 10 miners were
killed. MSHA's accident investigation report concludes that methane
concentrations of up to 6.5 percent were detected in the explosion area
prior to the explosion but reports by the mine foreman for the shift
failed to record the presence of these dangerous accumulations of
methane or show the action taken to correct the condition. The
investigation further found that the failure to record these methane
accumulations in the appropriate record books prevented management
officials and other interested persons from learning of the hazardous
condition and initiating corrective action. In light of the record, the
final rule adopts the proposal and requires the examiner to record the
results, whether corrected or not, of the preshift examination and the
action taken to correct hazardous conditions found during the preshift
examination. This would include hazardous conditions and their
locations and the results of methane and air measurements required to
be made elsewhere in Sec. 75.360.
[[Page 9797]]
As with other records required by this rule, the records of
preshift examinations may be kept either in secure books that are not
susceptible to alteration or electronically in a computer system so as
to be secure and not susceptible to alteration. A detailed discussion
of record books and the use of computers to maintain records can be
found in the General Discussion of this preamble.
A variety of comments were received regarding the countersigning of
preshift records by the mine foreman, and the time permitted for
countersigning. The final rule adopts the proposal that the mine
foreman or equivalent mine official must countersign the record of the
preshift examination by the end of the mine foreman's next regularly
scheduled working shift. The mine foreman is in a position of
responsibility for the day-to-day operation of the mine. It is
essential for the health and safety of the miners that the mine foreman
be fully aware of the information contained in the preshift examination
reports so as to be able to allocate resources to address safety
problems. Allowing until the end of the mine foreman's next regularly
scheduled working shift to countersign the reports provides sufficient
flexibility to make compliance practical while assuring that the mine
foreman is aware of the results of the examination in a reasonably
timely manner.
Some commenters suggested that the time for countersigning is
unnecessarily long, and that the final rule should restore a previous
requirement that countersigning be completed ``promptly.'' The term
``promptly'' involves ambiguity that is eliminated by specifying the
time for countersigning the preshift examination record. The rulemaking
record does not show that the time set by the final rule would expose
miners to safety or health risks. Commenters suggested that the term
``mine foreman'' be replaced by a ``certified person responsible for
ventilation of the mine or his designee.'' Another commenter suggested
that the record could be countersigned by the mine foreman or any other
mine official responsible for the day-to-day operation of the mine.
Commenters stated that some operations no longer use the terms ``mine
foreman,'' ``mine manager,'' or ``superintendent''. To provide for
alternative management titles, the final rule incorporates the phrase
``or equivalent mine official.''
Numerous comments were received regarding the proposal for second
level countersigning of the preshift examination record by the mine
superintendent, mine manager, or other mine official to whom the mine
foreman is directly accountable, within 2 scheduled production days
after the countersigning by the mine foreman. The final rule does not
retain this proposed requirement. A detailed discussion of the subject
of second level countersigning can be found in the General Discussion
section of this preamble.
Paragraph (f) of the final rule also contains revisions to the
existing rule to allow for electronic storage of records. Paragraph (g)
requires that the records required by Sec. 75.360 be maintained at a
surface location at the mine for one year and be made available for
inspection by authorized representatives of the Secretary and the
representatives of miners. A discussion of comments concerning the use
of computers to maintain records can be found in the General Discussion
of this preamble.
Section 75.362 On-Shift Examination
Like the preshift examination, the on-shift examination of working
sections is a long accepted safety practice in coal mining. As coal is
extracted, conditions in the mine continually change and hazardous
conditions can develop. Because the mining environment changes
constantly during coal production, this examination identifies emerging
hazards or verifies that hazards have not developed since the preshift
examination. Generally, the on-shift examination includes tests for
methane and oxygen deficiency, an examination for hazardous conditions,
and air measurements at specified locations.
The final rule adopts proposed Sec. 75.362 with the exception that
revisions have been made to the proposed provisions dealing with an
examination for compliance with the mine ventilation plan requirements
for respirable dust control.
The final rule redesignates existing (d)(1)(i) and (ii) as
(d)(1)(ii) and (iii), revises paragraphs (a)(1), (c)(1), (d)(1)(iii)
and (d)(2), removes paragraph (a)(2), and adds new paragraphs (a)(2)
and (d)(1)(i). Additionally, the requirements of existing paragraphs
(g) and (h), recordkeeping and retention, are transferred to
Sec. 75.363, Hazardous conditions, posting, correcting, and recording.
New paragraphs (g)(1) and (g)(2) are also added by the final rule.
The word ``on-shift'' has been added to the first sentence of
paragraph (a)(1) for clarity and consistency with other paragraphs of
Sec. 75.362. MSHA did not receive any comments on this proposed
revision. Paragraph (a)(1) is also revised as proposed to require a
certified person designated by the operator to conduct an on-shift
examination of each section where anyone is assigned to work during the
shift and any area where mechanized mining equipment is being installed
or removed during the shift. The existing rule required that an on-
shift examination be performed only on sections where coal is produced
and areas where mechanized mining equipment is being installed or
removed. Some commenters agreed that many of the same hazards exist on
a section whether coal is being produced or not. Commenters gave
several examples of activities that take place on non-coal producing
sections including equipment repair and maintenance, cutting and
welding, rockdusting, clean-up, and roof bolting. As indicated by these
commenters, all of these activities present the potential for a serious
accident. One commenter arguing against the proposed change stated that
the preshift and supplemental examinations already address the safety
concerns to which the proposal was directed. While MSHA considers the
preshift and supplemental examinations to be of great importance in
providing a safe work environment, these examinations are performed
prior to workers on a shift entering the mine or, in the case of the
supplemental examination, in an area of the mine that has not been
preshift examined. The on- shift examination is intended to address
hazards that develop during the shift. The concept of the on-shift
examination is not new. On-shift examinations of coal producing
sections have been required since the enactment of the Federal Coal
Mine Health and Safety Act of 1969.
Another commenter arguing against expanding the on-shift
examination requirement to non-coal producing sections stated that
requiring on-shift examinations of areas other than working sections
would detract from other required examinations. On-shift examinations
on coal producing sections are normally conducted by section foremen
who spend the vast majority of the shift on the section they are
supervising. These individuals will not normally conduct the on-shift
examinations in non-coal producing sections. These examinations will be
conducted by certified persons assigned to work in these areas or other
certified persons assigned to conduct these examinations. MSHA does
not, therefore, foresee reduced attention to examinations in working
sections.
Another commenter suggested that the requirements for on-shift
examinations be expanded further than proposed. The commenter stated
that many of the same types of activities that
[[Page 9798]]
occur on non-production shifts on the sections also occur in outby
areas of mines. In support of this recommendation the commenter pointed
to 4 explosions which occurred in outby areas of the mines. Those
accidents were the explosions at the Greenwich Collieries No. 1 Mine in
Pennsylvania in February 1984 where 3 miners were killed; the explosion
at the Day Branch Mine in Kentucky in 1994 where 2 miners lost their
lives and; an ignition at the Loveridge No. 22 Mine in West Virginia in
1992 that burned 1 miner. In each accident, several violations of
safety standards contributed to the explosion or ignition, including
inadequate or entirely omitted examinations required by standards in
effect at the time. Compliance with those safety standards would have
significantly reduced the likelihood of these tragic accidents
occurring. Likewise, requirements of this final rule, such as the
requirements for preshift and supplemental examinations in areas where
persons are assigned to work or travel, would have served well to
prevent these accidents.
The final rule requirements for on-shift examinations focus on the
areas most likely to develop hazards during a shift. Expanding the
examination requirements further is not supported by the record nor
needed for miner safety.
As proposed, the final rule also revises paragraph (a)(1) to
clarify that sufficient on-shift examinations must be conducted to
assure safety. One commenter suggested that MSHA should include
language to require more than one examination if necessary for safety,
as provided for in the previous standard. The final rule adopts this
approach and requires that at least once during each shift, or more
often if necessary for safety, a certified person designated by the
operator must conduct an on-shift examination of each section where
anyone is assigned to work during the shift and any area where
mechanized mining equipment is being installed or removed during the
shift. As with other changes to this section, comments were received
both supporting and opposing the change. One commenter in opposition to
the standard argued that although the operator is required to maintain
a safe work environment at all times, documentation should not be
required for each inspection that is made of the working environment
throughout the shift. The commenter is correct in stating that the
rule, in Sec. 75.363, requires additional documentation. However, the
only additional documentation required will be for hazardous conditions
found during the additional on-shift examination conducted on non-coal
producing sections where miners are working. The additional
documentation required does not override the need for the standard.
Another commenter suggested that the term ``more often if necessary for
safety'' be changed to ``more often if necessary for safety as
determined by the operator depending on the mining conditions at the
time.'' This commenter stated that conducting additional checks for
safety is a current practice and individuals working on the section,
including the section foreman, are the most familiar with conditions in
that area and should make the determination whether additional
examinations are needed. MSHA agrees with this commenter that persons
working on a section are in the best position to identify the need for
additional examinations. The suggested language has not been adopted,
however, because MSHA believes that this determination should not be
limited to persons working on the section.
Another commenter supported the proposal and listed explosions that
have occurred which, in the opinion of the commenter, could have been
prevented had additional on-shift examinations been made. MSHA agrees
that there are occasions when additional on-shift examinations are
necessary for safety and, therefore, the final rule requires that on-
shift examinations be conducted at least once each shift, or more often
if needed for safety.
The final rule retains the existing provision of paragraphs (a)(1),
(c)(1) and (c)(2) requiring an on-shift examination of areas where
mechanized mining equipment is being installed or removed. An in-depth
discussion of the reproposal of provisions concerning the installation
and removal of mechanized mining equipment is presented in the General
Discussion section of this preamble.
Paragraph (a)(2) adds a new on-shift examination requirement to
address respirable dust control. Under the final rule, before coal
production begins on a section, an examination for compliance with the
dust control measures established in the mine ventilation plan must be
completed. This examination includes measurement of air quantities and
velocities, water pressures and flow rates, a check for excessive
leakage in the water delivery system, and checks of the number of
operating water sprays and their orientation as well as the placement
of section ventilation control devices.
Assuring full compliance with these requirements is important in
safeguarding the health of miners. Human and financial costs
demonstrate the need for further attention. In 1990, approximately 2000
deaths were associated with Coal Worker's Pneumoconiosis and the total
number of deaths between 1968 and 1990 were over 55,000. As of 1993,
total annual Black Lung Program costs were over $1.3 billion and the
cumulative total cost had exceeded $30 billion.
Agency experience shows that needed attention has not always been
given to the proper functioning of respirable dust controls. For
example, a series of special spot inspections, undertaken in 1991 to
conduct checks of the dust control parameters during the course of
working shifts, revealed that 21 percent of the 781 mining units
sampled were not complying with one or more of their dust control
parameters. In its 1992 report, an MSHA Task Group recommended coal
mine operators be required to make periodic on-shift examinations to
verify that the mine ventilation plan parameters are in place and
functioning as intended. MSHA considers on-shift examinations of
respirable dust controls an important part of reasonable and prudent
respirable dust control strategy.
Several methods of measuring water spray pressures would be
acceptable. For example, water flow and pressure can be monitored
through the installation of an in-line water meter and a pressure
transducer. Water pressure can also be measured by permanently
installing a pressure gauge on a machine. Operators would determine the
working relationship between the pressure gauge reading and the actual
operating pressure at the sprays. Once the working relationship has
been established, the gauge pressure could be used to indicate the
actual spray pressure specified in the mine ventilation plan for a
given number and type of operating sprays.
Measurement of any required water flow rate could be accomplished
through the installation of a flowmeter. A flowmeter provides a direct
and reliable measurement and is the preferred method of determining
water flow rate. Another acceptable method of determining flow rate
would be to establish the relationship between the water pressure and
the spray orifice diameter, either through engineering data or through
actual tests. Once established, the water pressure gauge reading could
be used to reliably indicate a flow rate for a specific number of
sprays at a given orifice size.
One commenter, while generally supportive of the requirement for an
on-shift examination of respirable dust controls, expressed concern
over permitting the use of in-line flowmeters
[[Page 9799]]
and pressure transducers. The commenter stated that leaks in the
location of the flowmeter and pressure transducer could go undetected,
resulting in a loss of pressure and flow at the sprays. MSHA agrees
that undetected leaks could result in improper operation of the system.
To address this point, the final rule has been revised from the
proposal to require that a check for excessive leakage in the water
delivery system be made during the on-shift. This commenter also
suggested that use of incorrect spray nozzles could result in improper
operation of the system that would not be detected with in-line
flowmeters and pressure transducers. MSHA would expect that as part of
the examination of the number of operating sprays a check would be made
to assure that the proper sprays are being used.
The final rule requires that the number of water sprays and their
orientation be included in the examination. While spray orientation is
important in air-directing spray systems, such as sprayfans and
shearer-clearers, MSHA does not intend that precise angles be
determined during each examination. Rather, the examiner would be
responsible for assessing whether the direction and orientation of the
sprays are generally correct and in accordance with the requirements of
the mine ventilation plan.
The final rule also requires that the working section ventilation
and control device placement be examined for compliance with the mine's
ventilation plan. Mine ventilation, particularly where coal extraction
occurs, is a basic respirable dust control measure.
Any other respirable dust controls specified in the approved mine
ventilation plan are also included in the scope of the examination
required under the final rule. An example of such controls is the
cleaning and maintenance procedures for a wet bed scrubber installed on
a continuous mining machine. The examination would include a check to
assure that air inlets and discharges are not plugged. It is not MSHA's
intent that the air quantity produced by a machine-mounted scrubber be
measured as part of the on-shift examination required by paragraph
(a)(2), unless such a requirement is included as a part of the mine
ventilation plan.
MSHA is aware that through advances in technology it may be
feasible to continuously monitor air quantity and velocity, and spray
water flow rate and pressure. Continuous monitoring offers the
potential to further improve miner protection by providing real-time
data on the performance and condition of key dust control measures.
This information can be used to give early warnings of deteriorating
dust controls, allowing corrective action to be taken before the dust
control system fails to protect miners from excessive dust levels.
Although continuous monitoring will eliminate the need for periodic
physical measurements to verify proper operation of some dust controls,
visual observation of other controls will still be necessary. Among
these are the number and location of operating water sprays, their
general condition and orientation, the section ventilation setup and
control device placement, the check for excessive leakage in the water
delivery system, and other control measures where performance and
operating condition can only be assessed visually.
One commenter suggested that MSHA not permit the use of continuous
monitoring in lieu of physical checks because technology to permit such
monitoring is not as yet available. The final rule is intended to be
sufficiently flexible to permit the use of new technology, such as
continuous monitoring and sensing devices, and also to encourage the
introduction of such modern equipment. The final rule does not require
the physical measurement of the air velocity and quantity, water
pressure and flow rates if continuous monitoring of the dust control
parameters is used and indicates that the dust controls are functioning
properly.
The on-shift examination of the dust controls is to be completed
under the direction of a person who has been designated by the
operator. The proposal would have required that a certified person
conduct the examination. One commenter objected to this approach,
suggesting that the completion of this examination would require
considerable time and that a more thorough examination could be
accomplished by a person(s) familiar with the equipment and the dust
control measures being utilized. This commenter recommended that MSHA
remove the word ``certified'', thus permitting the examination to be
conducted by persons other than certified persons. A second commenter
argued that the examination should be conducted by a single individual
because other persons may be assigned to a section who are not familiar
with the requirements of the mine ventilation plan for that section.
The final rule deletes the word ``certified,'' permitting on-shift
examinations of dust controls to be conducted by one or more persons
who are not certified individuals. However, the examination must still
be conducted under the direction of a person designated by the operator
and as set out in paragraph (g)(2), a certified person must certify
that the examination has been completed. MSHA would expect that the
person directing this examination would be present at the site of the
examination while the examination is conducted.
Another commenter recommended that the final rule not specify the
measurements that are to be made need during the on-shift examination
of dust controls, and that the standard be rewritten to require such an
examination be sufficient to assure compliance with the respirable dust
parameters specified in the mine ventilation plan. Because it is
possible to identify specifically some of the parameters that must be
measured in all instances the suggestion of the commenter has not been
adopted. By identifying these parameters in the final rule,
misunderstandings over whether a plan specification is for dust control
or methane control, for example, can be eliminated.
As proposed, paragraph (a)(2) would have required that the
respirable dust control portion of the examination be made at or near
the beginning of the shift and before production begins on a section.
One commenter suggested that such a requirement would eliminate the
common practice of changing shifts on the section without an
interruption in production. MSHA recognizes that changing crews without
an interruption in production has become a common practice in some
areas and does not intend that this practice be changed by this rule.
The final rule has revised the proposal so that when a shift change is
accomplished without an interruption in production on a section, the
required examination may be made any time within 1 hour of the shift
change. In those instances when there is an interruption in production
during a shift change, the final rule requires that the on-shift
examination of respirable dust controls be made before production
begins on a section. The proposed wording ``at or near the beginning of
the shift'' has not been included in the final rule in recognition of
the fact that production on a section could be delayed and not begun
until well after the beginning of the shift. Because the purpose of the
standard is to assure that dust exposures are controlled during mining,
the on-shift examination must be conducted prior to the beginning of
production in order to be most effective.
Other commenters objected to examining respirable dust control
parameters for various reasons. Some commenters stated that operators
are
[[Page 9800]]
required to comply with the requirements of the mine ventilation plan
relative to dust control and a separate requirement is not needed. The
measurements specified in the final rule are a practical way to provide
reasonable assurance that miners are not being exposed to unhealthy
levels of respirable dust. The purpose of these checks is not to
restate the requirements for compliance with the mine's ventilation
plan. Instead, as discussed above, the final rule is intended to bring
needed attention to the proper functioning of dust controls before
production begins.
Other commenters expressed the opinion that coal production should
not be delayed until after the completion of the examination of dust
controls. According to these commenters, this examination will take the
certified person away from other examinations that must be completed to
assure safety. As explained previously, the final rule has been revised
to permit the changing of crews without an interruption in production.
The completion of the on-shift examination of dust control parameters
can be postponed for up to 1 hour when crews are switched out at the
face. Additionally, the final rule has been revised to permit the
examination of dust control parameters to be performed by a person(s)
other than a certified person and to simply require the certified
person to certify that the examination was completed. These revisions
substantially reduce any delay in production that could have resulted
under the rule as proposed.
Another commenter objected to the requirements of paragraph (a)(2)
stating that examination of dust controls is unnecessary because all
personnel are required to be trained in the requirements of all
approved mine plans including the mine ventilation plan, and many of
the required mine ventilation plan parameters are checked during the
pre-shift examination. The commenter stated further that other
parameters, such as number of water sprays and pressure, are checked by
the equipment operators during the pre-operational inspection. In the
opinion of the commenter, the proposed examination of dust control
parameters is redundant and unnecessary.
The requirements of paragraph (a)(2) are not redundant with
existing standards. There is no requirement for a pre-operational
inspection of dust controls. For the reasons discussed above, MSHA
considers examination of dust controls for proper functioning to be an
important practical measure for protecting miners'' health. To the
extent that these checks are currently being made by some operators,
together with the flexibility of the final rule, the burden of making
these checks is minimized.
The final rule requires in paragraph (a)(2) that deficiencies found
during the on-shift examination of dust controls be corrected before
production begins, or when crews are changed without an interruption in
production, before production continues. The proposal would have
required that deficiencies in the controls be corrected immediately.
However, the final rule revises the proposal in response to one
commenter who pointed out that the correction of deficiencies is
important prior to production, in view of the purpose of the rule.
Another commenter suggested that the examination of dust controls
be conducted after production begins so as to be more representative of
production conditions. In contrast, another commenter observed that if
the required dust control parameters are not being met before
production is begun, it is unlikely that they will be met after
production is started. This commenter suggested multiple examinations,
one before production begins and one at some later time during the
shift. MSHA agrees that if dust control measures are deficient before
production begins it is unlikely that they will be corrected later in
the shift. Therefore the final rule requires the on-shift examination
of the dust control measures prior to the beginning of production. The
final rule, however, does not include the recommendation for an
additional examination of dust control measures.
Paragraphs (c)(1) and (c)(2) require certified persons conducting
on-shift examinations to take air measurements at the same locations
where air measurements are required during the preshift examination.
This includes areas where mechanized mining equipment, including
longwall or shortwall mining equipment, is being installed or removed.
Reduced volume or velocity of air during the shift can contribute to
increased levels of respirable dust, methane accumulations, or oxygen-
deficient atmospheres. Checking the mine's ventilation system verifies
that changes in the mine ventilation system due to the production
process have not occurred.
The final rule removes the word ``working'' from paragraph (c)(1)
to assure that the application of the standard would extend to all
sections, consistent with paragraph (a). Many of the activities to
which miners are assigned are on sections not normally thought of as
``working sections,'' a term associated with coal production. For
purposes of Sec. 75.362, a section in the mine is considered to be the
area inby the loading point; or, in the case of the installation of
mechanized mining equipment, inby the proposed loading point; or, in
the case of the removal of mechanized mining equipment, inby the
location of the last established loading point. The final rule requires
in paragraphs (a)(1), (c)(1), and (c)(2) that the certified person
conducting the on-shift examination examine the section in much the
same way as it would be examined during a coal producing shift,
including checking for hazardous conditions, testing for methane and
oxygen deficiency, determining if the air is moving in its proper
direction, and measuring the volume of air in the last open crosscut or
in the intake of longwalls or shortwalls, as appropriate.
Some commenters objected to this provision stating that there is
little safety benefit to requiring on-shift examinations on sections
other than working sections where coal is being produced. The final
rule does not limit on-shift examinations to ``working sections'' but
includes other areas where persons are working. Hazards similar to
those that develop on a coal producing section can also develop during
a shift on sections that are not producing, but where personnel are
assigned to work.
Paragraph (d)(1)(i) requires that at the start of each shift,
before electrically operated equipment is energized, a qualified person
test for methane at each working place. One commenter suggested that
the existing standard is sufficient because quite often in today's
mining practices equipment is already energized at the start of the
shift since one equipment operator takes over from the previous
operator and examinations for methane have been performed every 20
minutes as required by Sec. 75.362(d)(1)(ii). MSHA does not agree that
the existing standard is sufficient for a number of reasons. First,
although the commenter is correct in stating that switching operators
while the equipment remains energized is a relatively common practice
it is not a universal practice. In mines where equipment is deenergized
between shifts, the final rule provides for a test for methane in each
working place prior to the equipment being energized. On sections in
mines where equipment operators are switched while equipment remains
energized, MSHA would consider a methane test performed during the
previous 20 minutes under paragraph (d)(1)(iii) as sufficient to comply
with the methane test requirement of paragraph (d)(1)(i) for the
working place where mining is taking place. However, paragraph
[[Page 9801]]
(d)(1)(i) also requires that methane tests be made in other working
places on the section not only in the working place where the equipment
is being operated.
The final rule requires in paragraph (d)(1)(iii) that methane tests
be made more frequently than 20 minutes if required in the approved
mine ventilation plan at specific locations, during the operation of
equipment in the working place. One commenter objected to this
requirement expressing the opinion that the standard does not identify
situations in which more frequent methane tests would be warranted and,
therefore, operators could be faced with a requirement to conduct
additional methane tests which are unwarranted and would result in the
misallocation of safety resources. The final rule is intended to
address situations such as an abnormally high methane liberation rate
in a mine or an area of a mine that would warrant more frequent testing
for methane. Like the existing standard the final rule requires this
test to be made by a qualified person, not a certified person, thus in
most cases the person who makes the test will be the machine operator.
As a result, this test will not require that other safety-related
activities be stopped to make a test for methane.
Under the existing rule, methane tests required by paragraph (d)(1)
were to be made at the last permanent roof support unless the mine
ventilation plan required that they be made closer to the face using
extendable probes. Paragraph (d)(2) of the final rule revises this
standard and requires that the methane tests specified in paragraphs
(d)(1)(i) through (d)(1)(iii) be made at the face from under permanent
roof support, using extendable probes or other means. Like the existing
standard, paragraph (d)(2) requires that for longwall and shortwall
mining systems, the tests are to be made at the cutting head. When
mining has been stopped for more than 20 minutes, methane tests must be
made prior to the start up of the equipment.
During informational meetings following the publishing of the
existing standard, it became apparent that a large segment of the
mining community felt that methane tests should be made as close to the
working face as practicable without exposing miners to unsafe
conditions. MSHA agrees that proper testing for methane at the face is
essential for safe mining operations. The need for making methane tests
at the face has been demonstrated by researchers and engineers from the
U.S. Bureau of Mines and MSHA through work performed over the last 25
years. This work documents that in a working place the concentrations
near the face are considerably higher than other areas in the working
place. For example, Luxner, in Bureau of Mines Report of Investigation
7223, ``Face Ventilation in Underground Bituminous Coal Mines,''
published in 1969, reported methane concentration in excess of 5
percent as far back as 15 feet using both blowing and exhaust
ventilation systems with a curtain-to-face distance of 20 feet. The
concentration outby this location as reported by Luxner was between
zero and 1 percent. Later, Haney, et al., also showed lesser
concentrations of methane further from the face using various types of
assisted ventilation systems.
A speaker at one of the public hearings on the proposal suggested
that tests should be made at the last row of bolts and if 0.2 percent
of methane is found at that location, a probe should be used to test at
the face. The final rule does not adopt this recommendation because
MSHA is unaware of any tests that relate the concentration of methane
at the face with the concentration at the last row of bolts. Based on
current knowledge, it is doubtful that such a direct correlation could
be made because of the number of variables involved.
A recurring comment concerning taking methane tests at the face
with a probe was that such a requirement will lead to an increase in
the number of back injuries among miners. However, other commenters
supported the requirement and stated that probes as long as 40 feet are
currently being used in some areas of the country. Miners with
experience in using these probes testified at the rulemaking hearings
that although the long probes can at times be difficult to use, they
are being used and are providing measurements of methane at the face in
mines operating in coal seams as low as 37 inches.
The possibility of an increase in the number of back injuries is of
serious concern to MSHA. However, after reviewing all of the written
comments and testimony taken during public hearings, particularly that
of miners having experience with the use of probes, MSHA is persuaded
that this is a reasonable approach and will achieve the desired safety
results without undue risk of back injuries.
Several commenters suggested that in lieu of requiring methane
tests at the face, MSHA should permit the use of the methane monitor to
satisfy the requirement. In making this recommendation, one commenter
suggested that the methane monitors should not be required to be
installed on face equipment if they cannot also be used to test for
methane in unsupported faces. Methane monitors have proven reliable
over the years and provide a second level of protection against methane
ignitions. Methane monitors provide for methane detection at a fixed
location while the use of a methane detector with a probe permits
methane measurements to be made at various locations in the face area.
Historically, machine-mounted methane monitors have been used as a
backup for the other required tests. This concept was exactly what
Congress recognized in Sec. 303(l) of the Coal Mine Health and Safety
Act of 1969 (Coal Act). Discussing this provision, the conference
managers noted ``...the methane monitor is an additional backup device
for detecting methane and should not be construed as a substitute for
the other tests and testing devices required in this title for
detecting and controlling methane.'' H.R. Conf. Rep. No. 91-761, 91st
Cong., 1st Sess. 80 (1969).
The final rule does not adopt the suggestion of commenters that
methane monitors be accepted in lieu of the methane tests required by
paragraph (d)(2).
Paragraph (g)(1) adopts the language of proposed paragraph (g) and
requires that the person making the on-shift examination in belt
haulage entries certify by initials, date, and time that the
examination was made at enough locations to show that the entire area
has been examined. As explained in the preamble to the proposal, the
existing rule does not require certification that examinations were
conducted in belt conveyor entries. Comments received expressed the
view that without certification, no mechanism exists to verify that
examinations were conducted in belt conveyor entries. Other commenters
questioned what MSHA meant by ``enough locations.'' MSHA agrees with
the commenter that the certification requirement should be added to the
rule to provide a means to verify that the examination has taken place.
With respect to the locations where the certification should be made,
this certification process is a common practice in the industry and is
required by several state regulations. The locations where
certification would be expected to be kept are no different than those
which were required for many years under the previous MSHA regulation
and which have been commonly accepted in the industry. Paragraph (g)(2)
is a new requirement relating to the certification of the examination
of respirable dust control parameters. Under (g)(2), the person making
the on-shift examination to assure compliance with the respirable
[[Page 9802]]
dust control parameters specified in the mine ventilation plan must
certify by initials, date, and time that the examination was made.
Section 75.363 Hazardous Conditions; Posting, Correcting, and
Recording
Section 75.363 is a new section requiring the posting, correcting
and recording of hazardous conditions. The posting of hazardous
conditions against entry is a time tested method for preventing
accidents. Examiners, upon finding a hazardous condition, erect
``danger boards'' to alert persons traveling in the area of the
presence of the hazard. In this manner, miners are prevented from
inadvertently entering an area where a hazard exists. Section 75.363
requires that hazardous conditions be posted and access to the area be
limited; that the hazardous conditions be corrected immediately or
remain posted; and, that a record be made and maintained of the
hazardous condition and the action taken to correct the condition.
Records of the hazards and the actions required to correct the hazards
provide valuable safety information about conditions in the mine and
the effectiveness of corrective measures.
MSHA's final rule modifies the proposal in several ways. The final
rule deletes the phrase ``or reported to'' that appeared in the first
sentence of proposed Sec. 75.363(a) and deletes the requirement for
countersigning by a second level official. It specifies that, except
for preshift or preshift type examinations, hazardous conditions shall
be corrected immediately or posted until the conditions are corrected.
The final rule allows for countersigning by an official equivalent to
the mine foreman and provides for storage of records in either a secure
book or in electronic media which is not susceptible to alteration.
It is essential that all hazardous conditions, regardless of when
detected or by whom, be adequately addressed. Commenters suggested that
the proposed standard be deleted because, in their opinion, other
standards provide adequate coverage. One commenter interpreted the
proposed standard as being directed at only those hazards found during
the on-shift examination and supplemental examinations, because
hazardous conditions found during the preshift and weekly are excluded
from the standard. This commenter recommended rewriting the
requirements for the on-shift and supplemental examinations to reflect
the needed changes.
Section 75.363 is not directed only toward hazardous conditions
found during examinations. Hazardous conditions occur and are found at
times during the shift when examinations are not being made. Under the
final rule, these hazardous conditions would also require posting,
correction, and recording when found by the mine foreman or equivalent
mine official, assistants to the mine foreman or equivalent mine
official, or other certified persons designated by the operator to
conduct examinations.
One commenter questioned whether the proposed standard was intended
to assign new duties to the mine foreman and assistant mine foremen.
The final rule does not impose additional responsibilities on the mine
foreman and assistant mine foremen. However, these individuals are
certified and routinely travel throughout the mine for purposes other
than making examinations. The standard requires that hazardous
conditions found by the mine foreman, assistant mine foreman, or
equivalent mine officials, be treated the same as hazardous conditions
found by other certified persons who have been designated to conduct
examinations. That is, the hazardous conditions are to be appropriately
posted, corrected, and recorded. The term ``equivalent mine officials''
has been added in response to commenters who suggested that the term
``mine foreman'' is no longer used at all mines.
Under paragraph (a) any hazardous condition found by the mine
foreman or equivalent mine official, assistants to the mine foreman or
equivalent mine official, or other certified persons designated by the
operator to conduct examinations is to be posted with a conspicuous
danger sign. The posting requirements of this section apply to every
hazardous condition regardless of when it is found. Under the proposal,
hazardous conditions reported to the mine foreman, assistants to the
mine foreman or other certified persons designated by the operator to
conduct examinations would have required posting. Commenters suggested
that requiring hazardous conditions ``reported to'' these individuals
would eliminate the judgement of the persons responsible for making
decisions about whether or not a hazardous condition exists. One
commenter suggested that the requirement, as proposed, could undermine
the integrity of the certified person. The final rule is revised to
require that hazardous conditions found by the mine foreman or
equivalent mine official, assistant mine foreman or equivalent mine
official, or other certified persons designated by the operator for the
purpose of conducting examinations shall be posted with a conspicuous
danger sign and shall be corrected immediately or remain posted. MSHA
would expect that when a hazardous condition is reported to these
certified persons, that the measures necessary to evaluate the
situation and, if necessary, to comply with the provisions of this
section would be taken.
One commenter suggested that the proposed requirement that all
hazardous conditions be corrected ``immediately'' would diminish safety
because miners could be exposed to hazards unnecessarily. The commenter
offered as an example an area of bad roof in a ``remote, unused
crosscut'' and suggested that in this case posting of the area against
entry would be sufficient. MSHA recognizes that there are instances,
such as the example presented by the commenter, where safety is best
served by simply posting the area against entry. This has long been the
practice in the industry and the final rule does not prevent this from
continuing. In these cases, the corrective action required to prevent
injury is to preclude persons from entering the area. The proposal
would have required that the hazardous condition be corrected
immediately and that the area remain posted until the hazardous
condition is corrected. To reflect the recommendation of the commenter,
the final rule requires that the hazardous condition be corrected
immediately or that the area remain posted until the hazardous
condition is corrected. The Agency recognizes that in some instances
posting the area against entry is the corrective action.
The requirement that the hazardous conditions be corrected
immediately does not necessarily require correction by the certified
examiner finding the condition. To do so could delay the completion of
the examination. Rather, the final rule requires that the hazardous
condition be corrected following the reporting of the condition by the
examiner to the appropriate mine official. Common sense and sound
judgement should enter into the decisions as to when hazardous
conditions are corrected. Posting of the area where the hazardous
condition exists in order to prevent entry is to be accomplished by the
certified person finding the hazardous condition.
One commenter questioned whether proposed paragraph (a) would
require the hazardous condition itself be posted. The posting of the
area, as opposed to the hazardous condition itself, would, in most
cases, be more effective and a safer practice. For instance, if a
section
[[Page 9803]]
of bad roof is detected, it would be in the best interest of safety to
mark the area or perimeter of the area of bad roof instead of the roof
itself. The ``danger'' sign would be placed at a location where anyone
entering the area of the hazardous condition would pass so that persons
approaching the area would be expected to see the ``danger'' sign. The
area would remain posted until the hazardous conditions are corrected.
The posting of areas where hazardous conditions exist to alert persons
is a long-standing accepted safety practice in the mining community.
Paragraph (a) requires that once an area is posted due to a
hazardous condition, only persons designated by the operator to correct
or evaluate the condition may enter the posted area. Additionally, if
the hazardous condition creates an imminent danger, everyone must be
withdrawn from the affected area to a safe area until the condition is
corrected. Persons referred to in section 104(c) of the Act are
permitted to enter in the area.
One commenter suggested that the representative of the miners be
permitted to enter an area which has been posted with a ``danger'' in
order to evaluate the condition. The final rule follows the statutory
provision in Sec. 104(c) of the Mine Act. This longstanding requirement
provides that only persons designated by the operator to correct or
evaluate the hazardous condition may enter such posted areas. With
respect to the representative of miners, Sec. 104(c)(3) provides that
the representative of the miners in such mine who is, in the judgment
of the operator or an authorized representative of the Secretary,
qualified to make mine examinations or who is accompanied by such a
person and whose presence in such area is necessary for the
investigation of the hazardous condition may enter the area.
Paragraph (b) requires that a record of hazardous conditions be
made by the end of the shift on which the condition was found. This
record is required to be maintained on the surface and must include the
nature and location of the hazardous condition and the corrective
action taken. A record of all hazards found, as well as the required
corrective action, serves as a history of the types of conditions that
can be expected in the mine. When the records are properly completed
and reviewed, mine management can use them to determine if the same
hazardous conditions are recurring and if the corrective action being
taken is effective. No record is required on any shift on which no
hazardous conditions are found. Paragraph (b) excludes hazardous
conditions found during the preshift and weekly examinations because
these examinations have separate record keeping requirements.
Commenters recommended rewording the standard to eliminate the
provisions that no record is required on any shift on which no
hazardous condition is found and that the corrective action taken must
also be recorded. These suggestions were offered to clarify the
standard. MSHA believes that deleting these requirements would not
clarify the rule and the suggestions are not adopted in the final rule.
Paragraph (c) requires that a record be made either by the
certified person who conducted the examination or by a person
designated by the operator. As with other records required by this
subpart, when the record is made by a designated person other than the
certified person making the examination, the person making the record
need not be certified. If the record is made by a person designated by
the operator, the certified person must verify the record by initials
and date. MSHA did not receive any comments objecting to this part of
the standard. Like the other recordkeeping requirements in the
proposal, proposed paragraph (c) would have required that the record be
made in a state-approved book or a bound book with sequential machine-
numbered pages. Additionally, the proposal would have required
countersigning by both the mine foreman and the superintendent or
equivalent individual to whom the mine foreman reports. The final rule
requires that the records of hazardous conditions must be kept in
either secure books that are not susceptible to alteration, or
electronically in a computer system so as to be secure and not
susceptible to alteration. A detailed discussion of record books and
the use of computers to maintain records can be found in the General
Discussion of this preamble.
A variety of comments were received regarding the countersigning of
the record by the mine foreman, and the time permitted for
countersigning. The final rule adopts the proposal that the mine
foreman or equivalent mine official must countersign the record of
hazardous conditions by the end of the mine foreman's next regularly
scheduled working shift. The mine foreman is responsible for the day-
to-day operation of the mine. It is essential for the health and safety
of the miners that the mine foreman be fully aware of the information
contained in this record so as to be able to allocate resources to
correct safety problems as they develop. Allowing until the end of the
mine foreman's next regularly scheduled working shift to countersign
the records assures that the mine foreman is aware of hazardous
conditions in sufficient time to initiate corrective actions.
Some commenters suggested that the time for countersigning is
unnecessarily long, and that the final rule should require daily
countersigning by the mine foreman. The rulemaking record does not
show, however, that the time set by the final rule would expose miners
to safety or health risks. Also, hazardous conditions must be corrected
immediately or the area must remain posted until the condition is
corrected.
Numerous comments were received regarding the requirement of the
proposal for second level countersigning of the preshift examination
record by the mine superintendent, mine manager, or other mine official
to whom the mine foreman is directly accountable within 2 scheduled
production days after the countersigning by the mine foreman. The final
rule does not retain this proposed requirement. A detailed discussion
of the subject of second level countersigning can be found in the
General Discussion section of this preamble.
As proposed, paragraph (d) of the final rule requires that the
records required by Sec. 75.363 be maintained at a surface location at
the mine for one year and be made available for inspection by
authorized representatives of the Secretary and the representative of
miners. Comments on this requirement were generally favorable. A
discussion of comments concerning the use of computers to maintain
records can be found in the General Discussion of this preamble.
Section 75.364 Weekly Examination
The weekly examination is directed at hazards that develop in the
more remote and less frequently visited areas of a mine. These areas
include: worked-out areas where pillars have not been removed, bleeder
entries used to ventilate worked-out areas where pillars have been
removed and, some main intake and return air courses. Over the course
of time, hazards such as methane accumulations and obstructions to
ventilation can develop in these areas and can result in an explosion
or loss of ventilation if not discovered and corrected. Because of the
confined nature of the underground mining environment, loss of life can
result in other areas of the mine outside the immediate location of the
hazard. The weekly examination assures that these hazards are located
and corrected.
Generally, Sec. 75.364 requires an examination in unsealed worked-
out areas that have not been pillared; travel
[[Page 9804]]
in bleeder entries and the performance of appropriate measurements in
these entries and; a check for hazardous conditions in return and
intake air courses, in each longwall travelway, at each seal along
return and bleeder air courses and each seal along intake air courses
not otherwise examined, in each escapeway, and each working section
that has not been preshift examined during the previous 7 days.
The final rule modifies existing Sec. 75.364 (a), (b), and (h). It
adopts several proposed changes to Sec. 75.364 and modifies or rejects
other proposed changes.
Paragraph (a) specifies weekly examination requirements in unsealed
worked-out areas where no pillars have been recovered as well as in
bleeder systems. The final rule requires that unpillared worked-out
areas and bleeder systems be physically examined on a weekly basis and
specifies the tests and measurements to be performed by the examiner.
The final rule identifies two separate locations within nonpillared
areas and bleeder systems where measurements may be required. First,
measurement points must be included in the mine ventilation plan to
identify the locations within unpillared worked-out areas and bleeder
systems where examiners will conduct air measurements and tests, the
results of which are to be recorded. These measurement points are not
in lieu of traveling the system, but rather are the locations where the
examiner will perform air quantity and quality tests and measurements
to determine the effectiveness of ventilation. These points are
tracking and evaluation tools to assure adequate ventilation and to
identify developing trends in ventilation or air quality which may
require attention.
Second, evaluation points may be approved in the mine ventilation
plan on a case-by-case basis as provided under (a)(1) and by
(a)(2)(iv). These evaluation points may be used in lieu of physical
examinations. Evaluation points may only be approved in lieu of travel
if the evaluation points are fully adequate to demonstrate that the
area is ventilated. These provisions are discussed below.
The final rule clarifies that measurement points for weekly
examinations must be specified in the mine ventilation plan for both
unpillared and pillared worked-out areas described in (a)(1) and
(a)(2)(iii), respectively. These measurement points are distinct from
the evaluation points which may be approved in lieu of a physical
examination under some circumstances. As mentioned above, evaluation
points are governed by (a)(1) for unpillared worked-out areas, and by
(a)(2)(iv) for pillared worked-out areas ventilated by bleeder systems.
Section 75.371(z) of the final rule refers to these requirements for
both measurement points and evaluation points. The measurement points
and evaluation points may be either in the body of the mine ventilation
plan or may be shown on the 75.372 map. In either case, the locations
are subject to approval by MSHA.
Under paragraph (a)(1), at least every 7 days a certified person
must examine unsealed worked-out areas where no pillars have been
recovered by traveling to the area of deepest penetration; measuring
methane and oxygen concentrations and air quantities and making tests
to determine if the air is moving in its proper direction in the areas.
The locations of measurement points where tests and measurements will
be performed must be included in the mine ventilation plan and must be
adequate in number and location to assure ventilation and air quality
in the area. Air quantity measurements must be made where the air
enters and leaves the worked-out areas. Sufficient methane and oxygen
measurements must be made to assure the air quality in the worked-out
areas. An alternative method of evaluating the ventilation of the areas
may be approved in the mine ventilation plan.
Under paragraph (a)(1), in addition to measuring oxygen and methane
concentrations and testing for proper air direction, air quantities
must also be determined. Air quantity measurements are required where
air enters and leaves the worked-out area. The final rule also requires
that a sufficient number of measurement points must be included in the
mine ventilation plan to assure appropriate ventilation and air quality
in the area.
The changes to paragraph (a)(1) are in response to comments and
MSHA experience with weekly examinations. Currently some examiners are
simply traveling to the point of deepest penetration while conducting
few if any tests or air measurements within the system. The full
benefit of an examiner traveling to the point of deepest penetration is
lost if the examiner does not conduct air quantity and quality
measurements at key locations.
The results of these measurements are important in assessing the
effectiveness of ventilation. In addition, trends in either air
quantity or quality can reveal developing problems which can be
corrected in the earliest stages.
One commenter suggested that the entire perimeter of worked-out
areas should be physically examined to all points of deepest
penetration. The commenter suggested that the face of each entry or
room should be examined at its point of deepest penetration. MSHA
agrees that travel to a single point of deepest penetration within an
area may sometimes be inadequate to fully demonstrate effective
ventilation of a worked-out area. The final rule addresses this issue
by requiring that measurement points be established in the mine
ventilation plan.
Paragraphs (a)(2) (i) through (iv) of the final rule retain the
requirement that at least every 7 days a certified person must evaluate
the effectiveness of bleeder systems used under Sec. 75.334 (b) and
(c). Like the proposal, the final rule also specifies tests and
locations for an effective examination. One commenter noted that mine
examinations are sometimes ineffective and supported the proposed
additional specificity in the rule, requiring air measurements and
tests at key locations or measurement points within worked-out areas.
Established locations where examiners will conduct air measurement and
tests will help assure effective examinations and provide quantitative
results to the operator. The final rule requires that the mine
ventilation plan include measurement points within worked-out areas and
paragraph (h) requires that the results be recorded.
Paragraph (a)(2)(ii) requires that measurements of methane and
oxygen concentrations be made, air quantity be measured, and a test
performed to determine if the air is moving in its proper direction at
a point immediately before the air enters a return split of air. A
commenter supported the proposed air measurements where air enters and
leaves worked-out areas and correctly noted that such measurements
would reveal some types of ventilation problems. In a special case,
such as where it may not be possible to measure intake air, paragraph
(a)(2)(iv) permits an alternate method of evaluation to be used when
approved in the mine's ventilation plan.
Another potential hazard exists when multiple intake openings lead
into such an area, if passing intake air enters upstream openings of
the worked-out area and reenters the intake from downstream openings.
The final rule also requires that air quantity measurements be made
where air enters and leaves worked-out areas. Measurements made where
air enters and exits the area will alert the examiner and operator to
airflow changes or imbalances which indicate a potentially dangerous
ventilation problem. The specification of
[[Page 9805]]
measurement points within worked-out areas will also assure that short
circuits have not interrupted ventilation.
One commenter stated that the standard should fully delineate all
aspects of the weekly examination by specifying that the examination
include roof and ribs, ventilation controls, water accumulations, etc.
Although MSHA agrees that these and other conditions fall within the
purview of the weekly examination, the final rule does not attempt to
provide an exhaustive list of what is to be covered in a weekly
examination. Examinations are performed by persons trained and
certified as able to make the required examinations. Such certified
persons can be expected to give proper attention to basic safety
considerations.
Paragraph (a)(2)(iii) requires that at least one entry of each set
of bleeder entries used as part of a bleeder system under Sec. 75.334
must be traveled in its entirety. Under the final rule, measurements of
methane and oxygen concentrations and air quantities are required to be
made during the examination. Also, a test to determine if the air is
moving in its proper direction must be made at locations or measurement
points, specified in the mine's ventilation plan. The measurements and
tests provide the information necessary to determine the effectiveness
of the bleeder system.
One commenter believed that the proposal would require each
parallel and common bleeder entry of a set to be traveled. The final
rule is intended to simplify the examination and would, under the
circumstances described by the commenter, require only one entry of a
set of common entries to be examined in a bleeder system. Also, similar
to the requirements for traveling intake and return air courses, this
requirement should not be interpreted to require the examiner to stay
in one entry. For example, if the examiner desires to ``zig zag''
between entries while traveling in a multi-entry bleeder system, this
would be acceptable under the regulation provided tests and
measurements are made at the appropriate locations.
Paragraph (a)(2)(iv) provides that, in lieu of the requirements of
(i) through (iii), alternative methods of evaluation may be specified
in the mine ventilation plan provided that the alternative method
results in proper evaluation of the effectiveness of the bleeder
system. One commenter cited several explosions that were related to
bleeder system deficiencies and linked poor design and inadequate
maintenance with the provision allowing examination at evaluation
points in lieu of traveling the area in its entirety. The thrust of the
commenter's argument was that an inflexible standard requiring either
full travel of a bleeder system or sealing of the entire area would
result in superior designs and improved maintenance. While MSHA agrees
with the commenter's ultimate objective of ensuring effective
ventilation of bleeder systems and worked-out areas, MSHA does not
agree that elimination of any flexibility within the standard would
result in infallible designs. Since approval of evaluation points is
only granted in cases where adequate ventilation can be determined
through evaluation, MSHA believes that retaining flexibility to review
individual cases is an appropriate method and results in proper
evaluation of the effectiveness of the bleeder system.
Paragraph (h) of the final rule governs recordkeeping requirements
for weekly examinations. The final rule incorporates several revisions
based on recommendations submitted by commenters. The final rule
requires that at the completion of any shift during which a portion of
a weekly examination is conducted, a record of the results be made.
This record must include any hazardous conditions found during the
examination and their locations, the corrective actions taken, and the
results and location of air and methane measurements. The record must
be made by the person making the weekly examination or a person
designated by the operator.
The final rule includes a revision requiring that the results of
methane tests must be recorded as the percentage of methane measured by
the examiner. Previously, terms such as ``ok,'' ``low,'' or ``trace''
were entered in record books as test results. The final rule clarifies
that such qualitative terms are not acceptable when examination
requirements specify the measurement of air quantity or methane levels
as such entries provide little useful information.
The final rule requires that if the record is made by a person
other than the examiner, the examiner must verify the record by
initials and date by or at the end of the shift for which the
examination was made. As with other records required by this rule, the
records of weekly examinations may be kept either in secure books that
are not susceptible to alteration, or electronically in a computer
system so as to be secure and not susceptible to alteration. A detailed
discussion of record books and the use of computers to maintain records
can be found in the General Discussion of this preamble.
Commenters suggested that the final rule only require the examiner
to record uncorrected hazardous conditions. MSHA is sensitive to
minimizing recordkeeping requirements and, for example, the final rule
requires only uncorrected defects found during the fan examination to
be recorded. However, the weekly examination record serves as a history
of the types of conditions that can be expected in the mine. When the
records are properly completed and reviewed, management can use them to
determine if the same hazardous conditions are occurring and if the
corrective action being taken is effective. Additionally, this record
can permit mine management, the representative of the Secretary, and
the representative of miners to better focus their attention during
examinations and inspections. The final rule adopts the proposal and
requires the examiner to record all hazardous conditions found and the
action taken to correct the hazardous condition.
A variety of comments were received regarding the countersigning of
the records of weekly examinations by the mine foreman, and the time
permitted for countersigning. The final rule adopts the proposal that
the mine foreman or equivalent mine official must countersign the
record of the weekly examination by the end of the mine foreman's next
regularly scheduled working shift. The mine foreman is in a key
position of responsibility relative to the day-to-day operation of the
mine. It is essential for the health and safety of the miners that the
mine foreman be fully aware of the information contained in the
preshift examination reports so as to be able to allocate resources to
correct safety problems as they develop. Allowing until the end of the
mine foreman's next regularly scheduled working shift to countersign
the reports assures that the mine foreman is aware of the results on a
regular and timely basis.
Numerous comments were received regarding the requirement of the
proposal for second level countersigning of the weekly examination
record by the mine superintendent, mine manager, or other mine official
to whom the mine foreman is directly accountable. A full discussion of
second level countersigning can be found in the General Discussion
section of this preamble.
Paragraph (h) of the final rule also contains revisions to the
existing rule to allow for electronic storage of records. Paragraph (i)
requires that the records required by Sec. 75.364 be maintained at a
surface location at the mine for one year and be made available for
inspection by authorized representatives of the Secretary and the
representatives of
[[Page 9806]]
miners. A discussion of comments concerning the use of computers to
maintain records can be found in the General Discussion of this
preamble.
Under the final rule, the record of weekly examinations must be
countersigned by the mine foreman or equivalent mine official by the
end of the mine foreman's next regularly scheduled working shift. Based
on comments noting that traditional mine management structures have
changes at some operations, the final rule provides that an official
equivalent to mine foreman may countersign the records. The purpose of
this change is to require that when a mine foreman is not present in
the mine's management structure, an equivalent official must perform
this function. As with the existing standard, second level
countersigning by the mine superintendent is not required by the final
rule.
The record of weekly examinations must be made in secure media not
susceptible to alteration. If records are made electronically, they
must be unalterable, shall capture dates and signatures, must be
accessible to representatives of the miners and the Secretary, and must
be capable of producing printouts. Further discussion of both the
issues of second level countersigning and acceptable record books or
electronic records can be found in the general discussion section of
this preamble.
The proposal, at paragraph (b), would have added a requirement that
the certified person examine for noncompliance with mandatory safety or
health standards that could result in a hazardous condition. The
proposal drew considerable objection. Commenters objected to the
unlimited scope of the term ``noncompliance,'' the legal propriety of
recording noncompliance, and the additional examination time required
to determine noncompliance, the diversion of the examiner's attention
away from key safety conditions to minor compliance issues. Even so,
another commenter supported the proposal as necessary, suggesting that
the earlier rule was intended to require operators to assure full
compliance through the required examinations. The commenter correctly
noted that a requirement to examine for safety and health violations
was in effect from 1970 until 1992 when it was deleted.
While the proposed standard appeared attractive in concept, the
majority of comments received indicate that the standard would result
in considerable confusion. In addition, it would be impractical to
define and adequately limit the scope of the requirement. Comments
consistently indicated confusion and misinterpretation of the
proposal's scope, offering a wide range of interpretations.
As discussed in the preamble to the 1992 rule, most hazards are
violations of mandatory standards. Requiring the examiner to look for
all violations regardless of whether they involve a distinct hazard
could distract the examiner from the more important aspects of the
examination. Despite an attempt in the proposal to limit the scope of
the examination for noncompliance to situations that, ``could result in
a hazardous condition,'' commenters expressed a high level of
misunderstanding. Although a similar requirement existed between 1970
and 1992, MSHA generally did not broadly apply the standard. After
consideration of all comments and a review of the history since the
current standard became effective, MSHA concludes that the existing
standard is appropriate and best serves the objective of giving
examiners clear guidance for making effective examinations.
Accordingly, the proposal for examinations to include noncompliance
with mandatory safety and health standards is not adopted in the final
rule.
Paragraph (b)(7) has been added to require that water pumps not
examined as part of a preshift examination conducted during the
previous 7 days be examined during the weekly examination. This
modification is an outgrowth of comments received in response to
proposed Sec. 75.360, which would have required examination of certain
pumps. As discussed in the preamble to Sec. 75.360, one commenter
persuasively argued that all pumps should be examined. Pumps that are
not preshift examined under the final rule are generally located in
remote areas of the mine. These pumps are appropriately examined on a
weekly basis.
Section 75.370 Mine Ventilation Plan; Submission and Approval
Mine ventilation plans are a long recognized means for addressing
safety and health issues that are mine specific. Individually tailored
plans, with a nucleus of commonly accepted practices, are an effective
method of regulating such complex matters as mine ventilation and roof
control. Section 75.370 requires that each mine operator develop and
follow a ventilation plan that is approved by MSHA and that is designed
to control methane and respirable dust in the mine. Section 75.370
further requires that the plan be suitable to the conditions and mining
system at the mine. In addition, Sec. 75.370 provides the procedures
for submittal, review and approval of the plan to assure that the plan
for each mine will address the conditions in that mine.
In this final rule, MSHA revises the existing plan submission and
approval process to provide an increased role for the representative of
miners in the mine ventilation plan approval process. This revision is
consistent with the statutory purpose that miners play a role in safety
and health.
The final rule redesignates existing paragraphs (b)(1) through (f)
as (c)(1) through (g), revises paragraphs (a)(3), (c)(1), and (f), and
adds a new paragraph (b). The proposal would have modified the existing
rule by providing that the representative of miners would receive a
copy of the proposed mine ventilation plan or proposed revisions at the
time of submittal to MSHA, and the approved plan upon approval by MSHA.
The existing rule provided that the submitted plan and the approved
plan were to be made available to the miners representative. Another
proposed change was to specify the length of time the submitted plan
and the approved plan would be posted at the mine. A new paragraph (b)
would allow for timely comments on the submitted plan from the miners
representative. Representatives of miners would receive written notice
of plan approval. The final rule, for the most part, adopts the
proposed rule. However, the final rule requires that the miners
representative be notified of the submittal of a mine ventilation plan
and revisions to a plan 5 working days prior to submittal and that the
representative of miners be provided with a copy of the plan upon
request. It also requires that MSHA provide a copy of miners''
representative comments to the mine operator upon request.
Final rule paragraph (a)(3) is divided into (a)(3)(i), (a)(3)(ii),
and (a)(3)(iii) and contains new requirements in (a)(1)(i) and
(a)(1)(iii). Paragraph (a)(3)(i) requires that the mine operator notify
the representative of miners that a mine ventilation plan or a plan
revision is to be submitted to the District Manager for approval. This
notification must be given at least 5 days prior to submission.
Paragraph (a)(3)(i) further requires that the operator provide a copy
of the plan or revision to the representative of miners at the time of
notification, if requested. Paragraph (a)(3)(ii) requires that the
proposed plan be made available for review by the representative of
miners, and paragraph (a)(3)(iii) requires that the proposed plan or
revision be posted on the
[[Page 9807]]
bulletin board at the mine and remain posted until it is approved,
withdrawn, or denied.
Commenters representing both operators and labor suggested that the
proposed plan or revision should be provided to the representative of
miners prior to being submitted to the district manager for approval.
One commenter suggested that the proposed plan or revision be provided
to the representative of miners 10 days prior to submittal and stated
that this could speed up the approval process by allowing the miners
affected to investigate the proposed change and by permitting the
operator and the representative of miners the opportunity to reconcile
differences prior to the operator's seeking approval. The commenter
pointed out that some existing wage agreements have adopted such a
requirement. The commenter suggested that the rule should also include
such a requirement because operators do not always comply with the
requirements of the agreement. This commenter further suggested that
there have been instances where plans have been revised and acted upon
before the representative of miners was aware that a revision was to be
made. Other commenters suggested that the proposed plan or revision be
provided 3 days prior to submittal. These commenters expressed
different reasons for the suggestion. One of these commenters stated
that the industry has historically maintained that since the plan is
submitted to the district manager for approval, and developed by the
mine operator, the requirement to provide copies to other parties is
contrary to the Mine Act. However, the commenters further stated that
their suggestion reflected an attempt to balance all interests and
resolve this matter.
These comments are constructive and MSHA has used all of them to
fashion a final rule which is consistent with the statutory purpose and
responsive to the mining community. One commenter attempted to relate
the rule to terms of a wage and hour agreement. MSHA does not intend or
have authority to affect any wage and hour agreement. MSHA believes
that the involvement of the miners and their representative in the plan
approval process will improve the health and safety of the Nation's
coal miners. As suggested by commenters, miners who work under the mine
ventilation plan are often in the best position to know the effect of
proposed revisions. MSHA has long recognized the importance of input
from the miners and their representatives in the plan-approval process.
The preamble to the existing standard discusses the role of miners and
their representatives in the development of mine ventilation plans in
detail. MSHA continues to believe that miners have a stake in the
implementation of the ventilation plan at each mine.
The final rule is consistent with the existing plan approval
process and does not change the process for developing and approving a
mine ventilation plan. The operator continues to be the party
responsible for developing the mine ventilation plan and MSHA continues
to be responsible for reviewing and approving the plan. The proposed
rule, in paragraph (a)(3)(i), would have required the operator to
provide a copy of a proposed mine ventilation plan or any proposed
revision to the representative of miners at the time of submittal to
MSHA. The final rule requires the operator to notify the representative
of miners of the submittal of the proposed plan or revision at least 5
working days prior to submittal to the district manager. In addition, a
copy is to be provided to the representative of miners upon request. In
most instances, this should provide sufficient time for a review of the
proposed plan or revision and a discussion between the operator and the
representative of miners over concerns that may exist.
In response to comments, paragraph (a)(3)(i) is further revised in
the final rule to reflect that there are occasions when mine
ventilation plans must be submitted and reviewed within a very short
time frame. In response to a question during one of the public hearings
on the proposed rule, one commenter stated that miners understand that
at times situations may arise that necessitate an operator submitting a
plan or revision to MSHA that will not allow for the ten (10) day
provision for the representative of the miners.
Paragraph (a)(3)(i) of the final rule requires that in the case of
a situation requiring immediate action on a plan revision, notification
of the revision shall be given, and if requested, a copy of the
revision shall be provided to the representative of miners by the
operator, at the time of submittal to the district manager. The final
rule does not include the recommendation of one commenter that the plan
or revision be provided to the representative of miners before
submittal because to so require could delay approval of a change
necessary to health and safety. Questions will undoubtedly arise
relative to what constitutes a situation requiring expedited action.
MSHA does not believe that it is possible or appropriate to set forth
all circumstances which would be covered by the standard. Should such a
situation arise, it would be handled by the district manager on a case
by case basis. Generally, the district manager would be guided by
whether the condition, if uncorrected, could result in a health or
safety hazard or an imminent stoppage of production in the mine or an
area of the mine.
Paragraph (a)(3)(ii) of the final rule retains the requirement that
a copy of the proposed plan or any proposed revisions be made available
for inspection by the representative of the miners. Although some
commenters thought this was superfluous in light of the requirement in
paragraph (a)(3)(i), MSHA believes that this requirement facilitates
the overall approval process.
Paragraph (a)(3)(iii) of the final rule retains the existing
requirement that copies of the proposed plan and proposed revisions be
posted on the mine bulletin board and clarifies that posting is
required at the time of submittal. MSHA believes that the posting
requirement is necessary to assure that all miners at a mine will have
the opportunity to review the proposed plan or revision and provide
input during the review process. One commenter suggested that proposed
plans or proposed revisions be required to remain posted for only 30
days from the time of submittal so as not to ``clutter up the bulletin
board.'' This suggestion has not been included in the final rule
because the mine ventilation plan impacts miners'' safety and health
and it is important for miners to know which plan provisions are in
effect versus those which have not been approved. Another commenter
suggested that proposed plans and revisions be posted 10 days prior to
submittal to MSHA. This recommendation has not been included in the
final rule to assure that there is no confusion between plans that are
approved and proposed provisions awaiting MSHA approval. To require
posting of proposed plan revisions prior to submission to MSHA would
create another category of mine ventilation plans which could result in
unnecessary confusion. This is particularly true since the
representative of miners will have the plan at least 5 days prior to
submittal. Because there are occasions where a representative of miners
does not feel it is necessary to review a plan or revision, the rule
only requires the operator to provide a copy of the plan or revision
upon request.
Paragraph (b) of the final rule specifies procedures that the
representative of miners may use to provide input in the mine
ventilation plan review process. Under the final rule, the
representative of miners may
[[Page 9808]]
submit comments on the proposed plan or revisions to the plan to the
district manager for consideration. Recognizing that in some instances
a decision relative to the approval or denial of a revision must be
made in a short time frame, the final rule requires that comments be
made in a ``timely manner.'' MSHA has not defined ``timely manner'' but
would consider it to be a period of time that does not unnecessarily
delay the approval process. The district manager will continue to be
available to discuss with the representative of miners all aspects of
the plan as they affect miners' health and safety at any time during or
following approval or denial of a proposed plan or revision. Commenters
suggested that the representative of miners be given a deadline for the
submission of comments similar to the time frame established in
paragraph (a)(3)(i) for the operator to provide copies of proposed
plans and revisions to the representative of mines. In support of this
recommendation, these commenters stated that unlimited time could
unnecessarily delay the approval process. This recommendation is not
included in the final rule due to the complexity of some plans and
revisions. MSHA's goals are for a process that includes both timely
review and approval and opportunity for input from miners and the
Agency believes both goals can be accomplished under the final rule.
MSHA does not believe that this provision will unnecessarily delay the
plan approval process since the final rule, like the proposal, requires
comments to be submitted in a timely manner.
One commenter suggested that comments submitted by the
representative of miners to the district manager as part of the plan
approval process should be provided to the operator. MSHA would expect
that during the five day period before the plan is submitted to the
district manager the operator and the representative of miners will
discuss the plan and inform the other of their respective positions.
MSHA would encourage the representative of miners to provide a copy of
their comments to the operator prior to submitting them to MSHA.
However, to assure that all parties to the plan approval process are
aware of each others position paragraph (b) of the rule provides that
the district manager will provide the operator with these comments upon
request.
Paragraph (c)(1) of the final rule is unchanged from the proposal
and retains the existing requirement that the district manager notify
the operator in writing of the approval or denial of a proposed plan or
proposed revision. Paragraph (c)(1) adds a requirement that a copy of
this notification be sent by the district manager to the representative
of miners. This provision is intended to assure that the representative
of miners is kept informed of the status of the plan approval. One
commenter pointed out that quite often, plan provisions are modified
during the review process and the final approved plan may be different
from that which was originally submitted. This commenter suggested that
when a change is made to a submission, the representative of miners
should be notified of the intended change and afforded the opportunity
to comment. MSHA agrees that changes to proposed plans do occur during
the review process. Consistent with MSHA's philosophy that all parties
to the plan approval process need to be aware of the status of a
proposed plan or revision, MSHA would expect that the operator would
inform the representative of miners of changes to the original
submittal. However, to require that notification be provided for each
and every change, no matter how minor, could effectively stop the plan
review and approval process. Therefore, the final rule does not adopt
the suggestion of the commenter. Some commenters interpreted paragraph
(c)(1) as requiring the district manager to provide a copy of the
approved plan to the representative of miners. Paragraph (c)(1) only
requires that the district manager provide to the representative of
miners a copy of the notification of approval or denial that is sent to
the operator.
Proposed paragraphs (f)(1), (f)(2) and (f)(3) are adopted in the
final rule. Paragraph (f)(1) is new and requires the operator to
provide the representative of miners with a copy of the plan or
revision following notification of approval, if requested. This
facilitates review of the plan or revision by the representative of
miners. Also, the final rule continues in paragraphs (f)(2) and (f)(3)
the existing requirements that the approved plan or revision be made
available for inspection by the representative of miners and be posted
on the mine bulletin board. Like the proposal, a new requirement in
paragraph (f)(3) also requires that an approved plan or revision must
be posted within 1 working day of notification of the approval and must
remain posted for the period that the plan is in effect. This helps to
assure that the miners themselves, as well as the representative of
miners, are aware of the provisions of the mine ventilation plan once
it is approved.
Commenters both supported and opposed paragraph (f). Those in
opposition suggested that some of the requirements were unnecessary in
light of other requirements in the standard. Those supporting the rule
suggested that the operator should be required to provide a copy of the
approved plan or revision to the representative of miners and to make
it available within 24 hours of notification of approval. Other
commenters stated that mine ventilation plan approvals are sometimes
sent to the company offices and not necessarily to the mine. They
stated that in these cases, there could be a delay in copies of the
approved plan or revision reaching the mine. MSHA crafted the final
rule in light of the existing paragraph (d) which requires that
operators instruct persons affected by the mine ventilation plan or its
revision prior to implementation. Changes to the plan do occur during
the approval process; MSHA would expect that the plan or revision would
be available to the person conducting the required training and,
therefore, would be provided to the representative of miners.
One commenter suggested that, because the approved plan is required
to be made available for inspection by the representative of miners,
there is no need for the plan or revision to be posted on the bulletin
board. This commenter identified some logistical problems associated
with posting of plans stating that removal of the plan from the
bulletin board could be a problem.
This same commenter proposed that notification of the miners of a
revision to the mine ventilation plan should be the responsibility of
the representative of miners. MSHA does not agree that making the plan
available for inspection by the representative of miners is an adequate
substitute for posting of the plan or revision so as to make it
available to all miners at all times. Nor does MSHA agree that the
responsibility for assuring that miners are aware of the requirements
of the plan is the proper function for the representative of miners.
MSHA recognizes that difficulties can exist in assuring that the
approved plan or revision is posted, however the safety benefits of
having the plan available to the persons affected by its provisions far
outweigh any logistical problems.
Section 75.371 Mine Ventilation Plan; Contents
Section 75.371 sets forth the information that the operator must
include in the mine ventilation plan. Because the plan deals with
situations
[[Page 9809]]
unique to a mine, the general rules applicable in other standards do
not fit. For the convenience of the reader, the standard that sets out
the general rule or provides for an option to include a provision in a
plan will generally cross reference to the appropriate paragraph in
Sec. 75.371.
MSHA proposed revisions to existing paragraphs (b), (s), (z) and
(bb) of Sec. 75.371 and reproposed existing paragraph (r). MSHA's final
rule adopts the proposal for paragraphs (s), (z) and (bb). MSHA revises
its proposed paragraph (r) to make conforming changes with other
provisions. Finally, the final rule retains the existing language for
paragraph (b).
As stated in the General Discussion section of this preamble,
provisions concerning the installation and removal of mechanized mining
equipment that were promulgated in May of 1992 as part of the safety
standards for underground coal mine ventilation were reproposed in May
of 1994 as part of this rulemaking for the purpose of receiving and
giving full consideration to all pertinent comments on this issue.
Paragraph (r) of the final rule is one of the provisions that was
reproposed. Section 75.325(d) of the final rule requires that areas
where mechanized mining equipment, including longwall equipment, is
being installed and removed be ventilated. Paragraph (r) of Sec. 75.371
requires that the quantity of air that will be provided be included in
the mine ventilation plan. Most commenters either supported the
provision, citing the explosion at the William Station Mine, or stated
that the standard was originally promulgated inappropriately and did
not substantively comment on the requirement. One commenter suggested
that the quantity of air specified in the plan under paragraph (r)
should represent the minimum quantity that will be provided and the
location specified should be identified as what would be typical so as
to give the mine the flexibility to adapt to varying mine conditions.
This recommendation is consistent with MSHA's intent and MSHA has
included it in the final rule to help clarify the rule.
One commenter suggested that the ventilation scheme shown in the
plan should be representative of the method of ventilation to be used.
MSHA agrees that the mine ventilation plan should include a method of
ventilation that is representative of that used in the mine. However,
MSHA has not adopted this suggestion since the plan must be specific
enough so that the operator, the miners, the representative of miners,
and MSHA are assured that all areas are being adequately ventilated.
Paragraph (r) of the final rule requires that the mine ventilation
plan include the location where air quantities will be provided, and
the ventilation controls that will be used to provide these quantities.
This language was included in the reproposed provision and in
Sec. 75.325(d), which requires that the quantity of air that will be
provided during the installation and removal of mechanized mining
equipment, the location where this quantity will be provided, and the
ventilation controls that will be used, be included in the mine
ventilation plan. In reproposing paragraph (r), MSHA inadvertently
excluded from Sec. 75.371(r) the requirement relative to the location
where the air quantity is provided. The final rule has been modified in
Sec. 75.371(r) to conform to the requirements of Sec. 75.325(d).
The final rule revises existing paragraph (s) to conform to changes
in Sec. 75.362(d)(1)(iii). The final rule deletes the portion of
existing Sec. 75.362(d)(2) which requires that the mine ventilation
plan include the location of tests which are to be made closer to the
working face than the last permanent roof supports using extendable
probes or other acceptable means. The final rule in paragraph
(d)(1)(iii) requires that the mine ventilation plan specify the
frequency and location of the methane tests if required more often than
20 minutes by Sec. 75.362(d)(1)(iii). One commenter suggested adding
the words, ``or at other locations and frequencies if approved by the
district manager and contained in the ventilation plan.'' The suggested
clarification is not necessary and has not been adopted in the final
rule.
The final rule revises paragraph (z) to conform to Sec. 75.364(a).
Section 75.364(a) addresses the measurements to be made to evaluate the
effectiveness of bleeder systems and the ventilation of worked-out
areas during the weekly examination. The final rule requires that the
locations where these measurements are made or alternative methods of
providing these evaluations be included in the mine ventilation plan.
One commenter suggested that the locations where air measurements are
made should not be required in the mine ventilation plan. The commenter
made a similar suggestion relative to the requirement in Sec. 75.364
that air measurements be made to evaluate the ventilation of worked-out
areas and determine the effectiveness of bleeder systems. According to
the commenter, since no specific air volume is required it is not
necessary to measure the volume present. The measurement of air
quantity, as well as the other measurements required by the existing
standard, are essential to evaluate the ventilation of worked-out areas
and determine the effectiveness of bleeder systems. The final rule,
therefore, does not include the suggested changes in either Sec. 75.364
or Sec. 75.371(z).
Another commenter suggested that since the current standards do not
require a specific volume of air in bleeder entries, it is unnecessary
to measure the air volume. Proper evaluation of the effectiveness of a
bleeder system can only be achieved by comparison of measurements taken
in the bleeder system. In most instances, one of the most important
measurements is the air quantity at strategic points in the bleeder
system. Therefore, the final rule includes the proposed requirement
that the locations where air quantity measurements will be made in the
bleeder system be specified in the mine ventilation plan.
Existing paragraph (bb) requires that the location of ventilating
devices used to control air movement through worked-out areas be
included in the mine ventilation plan. The final rule reinstates a
requirement contained in the previous regulation, that the location and
sequence of construction of proposed seals also be indicated. This
requirement is consistent with Sec. 75.334(e) which requires that the
sequence of construction of seals be specified in the mine ventilation
plan. Some commenters on paragraph (bb) and Sec. 75.334(e) suggested
that proper sequencing of seals can change due to mining conditions and
should not be made a part of the mine ventilation plan. Another
commenter suggested that because the time to get a plan approved can be
lengthy, it may even create unnecessary hazards. Proper sequencing of
seal construction is necessary for effective ventilation during
sealing. Therefore, the final rule requires the location and sequence
of the construction of seals be specified and approved in the mine
ventilation plan. If a delay in seal construction will result in a
hazard to miners, the review and approval of the plan can be expedited
as explained in the preamble discussion of Sec. 75.370.
One commenter on paragraph (bb) suggested that the locations of
stoppings, regulators, and bleeder connector entries are better shown
on the mine map with a notation that it is subject to approval under
Sec. 75.371. The existing standard permits appropriate information
required under Sec. 75.371 to be shown on the map required by
Sec. 75.372. This is explained in the preamble discussion for existing
Sec. 75.371. MSHA recognizes that some of
[[Page 9810]]
the information required to be submitted under Sec. 75.371 is best
shown on a map. Rather than require additional maps, this information
may be shown on the Sec. 75.372 map. When shown on the Sec. 75.372 map,
only that portion of the map that contains information required under
Sec. 75.371 is subject to approval by the district manager.
The proposal would have revised paragraph (b) to reflect the
proposed changes in paragraphs (c) and (d) of Sec. 75.312 allowing
alternative testing methods for main mine fan automatic closing doors
and fan signals. Because the final rule does not include the proposed
changes to Sec. 75.312(c) and (d), final rule Sec. 75.371(b) conforms.
Section 75.372 Mine Ventilation Map
The mine ventilation map provides a basis for understanding how a
particular coal mine is ventilated. An accurate and up to date map of
the mine enables the operator and MSHA to review the mine's ventilation
plan to determine the appropriateness of the ventilation system to the
conditions in the mine. Only through a thorough understanding of the
ventilation system can the operator and others determine whether the
system is capable of preventing methane accumulations, possible
explosions, and high levels of respirable dust. Generally, Sec. 75.372
requires that the necessary information be provided on the map.
The final rule revises existing paragraph (b)(3) and adds new
paragraphs (b)(19) and (b)(20). Paragraph (b)(3) addresses which
adjacent workings must be shown on the mine map. The final rule, like
the proposal, requires all known adjacent workings within 1,000 feet of
existing or projected mine workings to be shown on the mine map,
regardless of whether the workings are located on mine property or on
adjacent property. The existing rule required that only the adjacent
workings within 1,000 feet be shown if they are on mine property.
MSHA has concluded that it is necessary to require that the mine
ventilation map include all known workings located in the same coalbed
within 1,000 feet of existing or projected workings, regardless of
whether the workings are located on the mine property. Hazards, such as
methane and water accumulations and irrespirable atmospheres, exist in
old workings whether located on mine property or not. MSHA also notes
that this revision makes paragraph (b)(3) consistent with existing
paragraph (h) of Sec. 75.1200, Mine map. Paragraph (h) of Sec. 75.1200
requires that the mine map show all adjacent mine workings within 1,000
feet. Like the previous standard, this revision would assure that all
adjacent mine workings appear on the Sec. 75.372 map in those cases
where operators do not use a Sec. 75.1200 map for their required
submission.
One commenter suggested that this requirement not be included
because mine operators have no legal obligation or authority to force
an adjacent land owner to provide the required information. MSHA
recognizes that the mine operator may, in some instances, have
difficulty obtaining this information. The hazards that exist within
abandoned mines, however, warrant such a requirement. Additionally, as
noted previously, this requirement is consistent with the requirements
of Sec. 75.1200(h) and will, therefore, impose no additional burden on
the operator. Agency experience reveals that the existing standard,
Sec. 75.1200(h), has not proven to be practically difficult for
compliance. In addition, this information would be available to the
miners and would enhance their understanding of the ventilation system
and aid them in the event of an emergency.
Another commenter suggested that the rule explicitly require that
all mine workings, including workings from auger mining, highwall
mining and strip mining, be shown on the map. This recommendation has
not been included in the final rule because MSHA believes that the
final rule is clear and requires any workings from other mines, such as
strip, auger and similar workings, to be shown if they are in the same
coalbed and are within 1,000 feet of existing or projected mine
workings.
Proposed paragraph (b)(19) is adopted in the final rule. The
proposal was drafted in response to comments received at public
meetings. It reinstates the requirement in the previous standard that
the mine map include the entry height, velocity and direction of the
air current at or near the midpoint of each belt flight where the
height and width of the entry are representative of the belt haulage
entry. Paragraph (b)(19) of the final rule should assist the examiner
in rapidly determining whether the air is flowing in its normal
velocity and direction during examination of the belt entry required
elsewhere in subpart D. One commenter suggested that this requirement
is redundant because the mine ventilation plan already requires that
this be ``illustrated''. MSHA does not agree that the requirement is
redundant since there is no such requirement in the mine ventilation
plan.
MSHA emphasizes that like much of the information required to be
shown on the ventilation map, this information would not be subject to
approval. When shown on the Sec. 75.372 map, only that portion of the
map that contains information required under Sec. 75.371 is subject to
approval by the district manager. The information required by paragraph
(b)(19) does not fit this criteria and therefore is not subject to
approval by the district manager.
As explained in the discussion of Sec. 75.301, instances have
developed where operators direct air from an intake air course to
ventilate shops, electrical installations, or for other purposes, and
this air is then coursed to the surface and is not used to ventilate
working places. Under one interpretation of the existing definition,
because this air has not ventilated a working place or a worked-out
area, the air course cannot be considered a return air course. In these
instances, the final rule in Sec. 75.301 expressly permits the
redesignation of the affected portion of the air course as a return air
course. Because it is important that personnel, including examiners,
the miners' representative, and representatives of the Secretary, know
which air courses have been redesignated, the final rule requires that
these air courses be shown on the map. Paragraph (b)(20) requires that
the location of redesignated air courses be shown on the ventilation
map. Commenters were supportive of this provision.
Section 75.380 Escapeways; Bituminous and Lignite Mines
When a fire, explosion or other emergency necessitates an immediate
evacuation of a mine, the designated route for miners to leave the mine
is the escapeway. The escapeway should be appropriately located and
designed to be free of obstructions and hazards to assure safe passage
from the hazardous underground environment. The final rule addresses
requirements for escapeways. Paragraphs (b)(1) and (b)(2) set forth the
requirements for the location of the escapeway when installing and
removing mechanized mining equipment. Paragraphs (d)(3) through (d)(5)
deal with the minimum dimensions of escapeways. Paragraph (f) addresses
the equipment that can be used in escapeways and the requirements for
fire suppression systems on this equipment. Finally, paragraph (i) sets
the minimum slope of an escapeway.
The final rule republishes existing paragraphs (b)(1) and (b)(2)
and revises paragraph (d)(3) through (d)(5), (f) and (i)(2).
Sections 75.380 (b)(1) and (b)(2) of the final rule deal with
escapeways on
[[Page 9811]]
working sections and areas where mechanized mining equipment is being
installed or removed. MSHA adopts the proposal in the final rule. An
in-depth discussion of the proposal of provisions concerning the
installation and removal of mechanized mining equipment is presented in
the General Discussion section of this preamble.
MSHA specifically solicited comments on those portions of the
proposal dealing with the installation and removal of mechanized mining
equipment, including paragraphs (b)(1) and (b)(2) of Sec. 75.380. These
paragraphs require that an escapeway be provided to areas where
mechanized mining equipment is being installed or removed. Only one
substantive comment was received. The commenter suggested that the
location of the beginning of the escapeway during equipment
installation and removal should be specified in the mine ventilation
plan to minimize the potential for congestion during movement of heavy
equipment. The commenter stated that the proposal would eliminate all
access to a longwall during the installation or removal of the longwall
equipment except for the face crosscut, and lead to accidents.
MSHA believes that the location where the loading point will be
installed and where the loading point was last located prior to removal
are easily identifiable and offer the best choice. The suggestion of
the commenter has not been adopted in the final rule. In addition, the
commenter noted that mobile equipment was needed during the
installation and removal of longwalls; this equipment can be used in
the escapeway if properly attended and protected with proper fire
suppression.
As with the existing rule, paragraph (d)(3) of the final rule
generally requires escapeways to be maintained to a height of 5 feet
from the mine floor to the mine roof, excluding the thickness of any
roof support. To accommodate mines in low seams, the rule provides that
where the coalbed is less than 5 feet, the escapeways shall be
maintained at least to the height of the coalbed. As in the past,
convergence, the reduction in entry height due to roof sag or floor
heave, which occurs as a natural geologic process, will be excluded
when determining escapeway height unless it would impede the escape of
miners, including disabled persons, in the event of an emergency. The
final rule modifies (d)(3) to provide that in areas of mines where
escapeways pass through doors or in areas of mines developed before
November 16, 1992 where escapeways pass across or under overcasts or
undercasts, the height of the escapeway may be less than 5 feet
provided the height is sufficient to enable miners, including disabled
persons, to escape quickly in an emergency. It was brought to the
attention of MSHA by one commenter that in some instances the removal
of roof support or the lowering of the tops of overcasts may be
necessary to provide the 5-foot height required by the existing rule.
It has been suggested that this could result in a diminution of safety.
One commenter suggested that escapeways should be 6 feet in width
and 5 feet in height without exception. This suggestion has not been
adopted in the final rule. Under the previous rule, escapeway
dimensions were addressed through criteria and operators routinely
requested and received approval for lesser dimensions than that in
criteria based on a performance test referred to as a ``stretcher
test.'' As applied, this test required 4 persons to carry a fifth
person on a stretcher through the area in question. The purpose of the
``stretcher test'' was to demonstrate that the lesser dimension would
not delay escape. The final rule permits lesser escapeway heights and
widths under specific circumstances provided the height and width
maintained enable miners to escape quickly in an emergency. The final
rule requires that when there is a need to determine whether sufficient
height or width is provided, MSHA may require a stretcher test where 4
persons carry a miner through the area in question on a stretcher.
This commenter suggested that the results of a stretcher test could
be manipulated by having the most fit miners carry the smallest miner.
MSHA continues to believe that the stretcher test is appropriate.
MSHA's experience is that the stretcher test provides a good measure of
the ability of miners to escape.
Since the escape of miners is not impeded, the demonstration that
there is no delay in escape assures that there is no reduction in
safety.
MSHA received similar comments regarding the dimensions of
escapeways developed on or after November 16, 1992, (the effective date
of the existing rule). Commenters suggested that where these escapeways
pass across or under overcasts or undercasts, the height of the
escapeway should be permitted to be less than 5 feet provided the
height is sufficient to enable miners, including disabled persons, to
escape quickly in an emergency situation. This suggestion is not
adopted in the final rule since sufficient clearance should have been
provided in these escapeways through proper planning and engineering.
Also, MSHA's experience does not reveal any compliance problems
associated with the standards since November 1992.
One commenter recommended changing the phrase ``disabled persons''
in paragraph (d)(3) to ``injured persons.'' In support of this
recommendation, the commenter stated that the phrase is intended to
include persons who may be injured but not necessarily disabled. MSHA
does not believe that the change is needed since there are many
situations that occur underground that can result in a person being
injured but not severely enough to need assistance (i.e. disabled) to
be transported from the mine. An escapeway that will permit the
transport of disabled persons, i.e. the more severely injured persons,
can be expected to accommodate persons with lesser injuries. The term
disabled with respect to the concept of injured has existed in the
regulations for over 25 years and MSHA is not aware of any problems
with its use.
Questions arose during informational meetings regarding the
requirements for the height of doors in escapeways. The final rule,
like the proposal, permits door heights of less than 5 feet under
certain conditions. Under the previous rule, escapeway dimensions,
including door heights, were addressed through criteria and operators
routinely requested and received approval for lesser dimensions than
that in criteria based on a performance test referred to as a
``stretcher test.'' Under the final rule, door heights of less than 5
feet are permitted provided the operator can demonstrate that persons,
including disabled persons, can escape without delay. The method of
demonstration would be the stretcher test, the same as for the
escapeway. Additionally, there are normally few doors in an escapeway
and the distance traversed in a door is very short. Passing the
stretcher test assures that there would be no diminution of safety
under the new provision. Also, since significant pressure differentials
can exist in escapeways, doors which are less than 5 feet are easier to
open.
Paragraph (d)(4) of the existing rule requires the escapeways be
maintained at least 6 foot wide with some exceptions. Widths of less
than 6 feet are permitted in either the primary or the alternate
escapeway in instances where supplemental roof support is necessary and
where the route of travel passes through doors or other permanent
ventilation controls. In both cases, existing paragraph (d)(4) requires
that the escapeway be at least 4 feet wide. Under the final rule,
paragraph (d)(4)(iii) permits the alternate
[[Page 9812]]
escapeway to be less than 4 feet wide under certain conditions.
Paragraph (d)(4)(iii) applies to the alternate escapeway only and
allows the escapeway width to be less than 4 feet for the same
conditions addressed in paragraphs (i) and (ii) if it can be
demonstrated that sufficient width is maintained to enable persons,
including disabled persons, to escape quickly in an emergency. The
conditions that could warrant lesser widths are the locations where the
alternate escapeway passes through doors or other permanent ventilation
controls, including constructed approaches to permanent ventilation
controls and facilities addressed in paragraph (d)(6), or where
supplemental roof support is required.
One commenter stated that the alternate escapeway should be
maintained at a minimum width of 4 feet without exception and noted
that on several occasions miners have been forced to use the alternate
escapeway in emergencies. The commenter noted that it could be
difficult to transport an injured person on a stretcher at widths under
4 feet. The final rule requires that when there is a need to determine
whether adequate width is provided, the stretcher test would be
applied.
Under the previous rule, approval had been granted for reduced
escapeway widths based on the stretcher test. These approvals were due
to the need to provide additional roof support and, in some cases, the
need for passage through ventilation controls. Additionally, as newer
portions of a mine age and require additional roof support, the final
rule allows widths of less than 4 feet in the alternate escapeway where
this roof support exists, provided the stretcher test is passed. MSHA
believes this approach achieves the intended result of the standard
while at the same time addressing the safety issues of providing
necessary supplemental roof support and permitting travel in the
alternate escapeway.
The preamble to the proposal stated that under the existing
standard Sec. 75.380(d)(4) mobile equipment should not be considered
when determining escapeway width unless the equipment has been
permanently abandoned in the escapeway or would be obstructing the
escapeway for a significant portion of a shift. Commenters objected
that this interpretation would be unduly restrictive and impractical.
Commenters noted that certain parked mobile equipment would enhance
miner safety where the equipment could be used to transport people out
of the mine in the event of an emergency.
Experience under the existing and the previous rule indicates that
track-mounted and rubber-tired equipment which could be used for
evacuation should be excluded when determining escapeway widths. Track-
mounted supply cars enhance safety by providing a readily available
supply of rock dust, roof support material, and other essential safety
related material. Section 75.214 requires that a supply of
supplementary roof support material and the tools and equipment
necessary to install the materials be available at a readily accessible
location on each working section or within 4 crosscuts of each working
section. In contrast, the Agency received comments that escapeways
should be maintained at least 6 feet in width except in rare cases
where roof supports could reduce the width to no less than 4 feet over
a limited distance.
The final rule takes a practical approach, preserving the
requirement that escapeways must be of sufficient width to enable
miners, including disabled persons, to escape quickly in an emergency.
The final rule also recognizes that certain necessary mining and
transportation equipment is located on and near working sections. For
example, necessary supply cars containing safety related material like
rock dust, roof support, ventilation control construction material,
etc., is allowable. Additionally, longwall section equipment commonly
includes, but may not be limited to, starter box, water pump, section
belt tailpiece and takeup assembly, section transformer, and emulsion
pump. Because this equipment is necessary to the operation of the
longwall, it also is permitted to be in the escapeway near the working
section under the final rule. In continuous miner sections as well as
longwall sections, mantrips and personnel transportation equipment,
which could be utilized in an emergency evacuation, is allowable. The
final rule would not prohibit this equipment in escapeway entries on or
near working sections. The rule would require, however, that sufficient
clearance be maintained to permit rapid escape.
This aspect of the final rule maintains the historical approach
taken to addressing issues of clearance in the confined environment of
underground coal mines. The final rule, while permitting reduced
dimensions near working sections as discussed above, requires that the
escapeways always be maintained of sufficient width to enable miners,
including disabled persons, to escape quickly in an emergency. As
discussed elsewhere in this preamble, the Agency will assess the
adequacy of escapeway widths in such areas by means of the stretcher
test to assure that the width is sufficient to enable miners, including
disabled persons, to escape quickly in an emergency.
Like the proposal, the final rule in paragraph (d)(5) revises the
existing language dealing with the location of escapeways. It provides
that escapeways shall be located to follow the most direct, safe and
practical route to the nearest mine opening suitable for the safe
evacuation of miners. A question arose during an informational meeting
as to whether MSHA intended that the existing rule eliminate the
requirement that escapeways be routed to the ``nearest mine opening.''
It was not MSHA's intent to change this requirement from the previous
standard. The existing requirement that the escapeway follow the most
direct route to the surface would, in fact, require the route to go to
the nearest mine opening. However, to eliminate any confusion that may
exist, the final rule revises paragraph (d)(5) and adopts language
similar to that in previous regulation, Sec. 75.1704-2(a), that is,
that the escapeway must follow the most direct, safe and practical
route to the nearest mine opening suitable for the safe evacuation of
miners.
One commenter stated that escapeways should not be permitted to
pass an opening to be routed to a more distant opening. Another
commenter stated that the nearest mine opening may not always be the
safest due to roof conditions or other factors. MSHA acknowledges that
the nearest mine opening may not always be the safest route to the
surface. A number of factors affect whether or not the safest, most
direct, practical route has been selected. These factors include roof
conditions, travel height, fan location, physical dimensions of the
mine opening, and similar considerations. For example, if bad roof
conditions are present along the shortest direct route and those roof
conditions are beyond reasonable control, then an alternate ``safe''
route designated by the mine operator may be appropriate. However, the
presence of roof falls does not necessarily indicate that the
passageway would not be suitable for evacuation if it is reasonable to
rehabilitate the area. By way of another example, where coal seam
thickness varies to the extreme, the shortest route may be through
lower coal, making travel relatively slow and difficult. An alternate
route through a high passageway may permit easier travel. Such an
alternate route, although longer, may be more practical and therefore
may be more appropriate.
[[Page 9813]]
Similarly, there can be other instances where the ``nearest mine
opening'' may not be suitable for safe evacuation of miners. For
example, an old mine shaft may not be safe for travel because of badly
deteriorated conditions, such as a deteriorated shaft lining or
deteriorated timbers, even though the shaft is still suitable for mine
ventilation purposes.
As with the existing standard, mine development projections do not
have to be altered to provide additional rooms, entries, or crosscuts
for the sole purpose of providing a passageway to the nearest mine
opening. However, the construction of ventilation controls such as
stoppings, overcasts and undercasts, or the installation of an escape
facility may be required to provide the most direct, safe and practical
route to the surface.
One commenter suggested that MSHA should require an escapeway plan
to be approved by the MSHA district manager to assure the most direct
route to the surface. Existing standards require that escapeways be
shown on the ventilation map. In addition, as with other regulations,
inspectors assess whether escapeways follow the most direct, safe and
practical route to the surface during each regular inspection.
Accordingly, MSHA does not believe that an additional plan is
necessary.
Existing paragraph (f) establishes the requirements for ventilation
of the primary escapeway and identifies which equipment can be operated
in the primary escapeway and the fire suppression requirements for this
equipment. The final rule, like the proposal, modifies paragraph (f) to
explicitly identify the equipment that is not permitted in the primary
escapeway and to specify the types of fire suppression systems that are
to be used and the conditions under which each is to be used on
equipment permitted in the primary escapeway. This is done by replacing
existing paragraphs (f)(1) and (f)(2) with paragraphs (f)(1) through
(f)(7) in the final.
Existing paragraph (f)(1) requires that one escapeway that is
ventilated with intake air be designated as the primary escapeway and
prohibits certain equipment from being used in the primary escapeway in
areas developed after November 15, 1992. Further, paragraph (f)(1)
requires fire suppression systems on mobile equipment that is operated
in the primary escapeway. The final rule transfers the part of existing
paragraph (f)(1) that specifies the area of the primary escapeway
affected to paragraph (f)(2).
The existing rule limited the installation or use of certain
equipment in areas of the primary escapeway developed after November
15, 1992. Paragraph (f)(2) of the final rule modifies the existing rule
for clarity and expands the application of certain requirements
contained in paragraphs (f)(3) through (f)(7) to the entire primary
escapeway except those areas of the primary escapeway developed prior
to March 30, 1970 where separation of the primary escapeway from the
belt and trolley haulage entries did not exist as of November 16, 1992.
For areas of mines developed after September 15, 1992, (those areas
covered by the existing rule) the provisions of paragraphs (f)(3)
through (f)(7) will be effective as of March 11, 1997. For other areas
covered by the rule, MSHA has provided for a 1 year phase in period to
allow mine operators time to effectively plan and implement the
necessary changes. The phase in period applies to areas of a primary
escapeway developed between March 30, 1970 and November 16, 1992, and
to areas of the primary escapeway developed prior to March 30, 1970
where separation of the belt and trolley haulage entries from the
primary escapeway existed prior to November 16, 1992.
Paragraph (f)(3) prohibits certain equipment from being in the
primary escapeway. Paragraphs (f)(4) and (f)(5) deal with fire
protection for mobile equipment that is permitted in the primary
escapeway and paragraph (f)(6) addresses a specific circumstance when
mobile equipment may operate in a primary escapeway without a fire
suppression system. Paragraph (f)(7), a provision added to the proposed
language in response to comments, allows the use of designated
emergency vehicles or ambulances in the primary escapeway.
One commenter suggested that the final rule should not provide an
exception for all areas where separation of the primary escapeway from
the belt and trolley haulage entry does not exist. The commenter
recognized, however, that Congress granted an exemption from separation
requirements for areas of the primary escapeway developed prior to
March 30, 1970, the effective date of the Act. The intent of the
proposal was to provide an exemption from the requirements of proposed
paragraphs (f)(3) through (f)(6) for these same areas. The commenter
points out that the proposal would have extended the exemption to other
areas of the primary escapeway where, for one reason or another,
separation did not exist on November 16, 1992, the effective date of
the existing rule. The final rule modifies the proposal to clarify that
the exemption only applies to those areas of the escapeway that were
developed prior to March 30, 1970 and where separation did not exist on
November 16, 1992.
Another commenter correctly interpreted proposed paragraph (f)(2)
as extending the requirement that limits the types of equipment
permitted in primary escapeways to areas of the mine developed prior to
November 16, 1992. The commenter stated that the proposed regulation
would pose great cost to the industry with no appreciable safety
benefit derived. A review of the fire history relative to both
stationary and mobile equipment indicates that fires can and do occur
on this equipment. Mobile equipment by design is intended to provide
flexibility in movement and is capable of operating anywhere in the
mine. Although the accident reports do not specify whether the mobile
equipment that caught fire was in the primary escapeway when the fire
started, it is reasonable to conclude that at least some of these fires
did occur in the primary escapeway. MSHA continues to believe that
given the importance of the primary escapeway to the safety of miners,
the extension of the requirements for operation of equipment in the
primary escapeway is necessary and appropriate.
Paragraph (f)(3) lists the equipment that is not permitted in the
primary escapeway. Under paragraph (f)(3)(i) of the final rule,
operating diesel equipment without an automatic fire suppression system
is prohibited in the primary escapeway unless it is attended, except as
provided in paragraphs (f)(6) and (f)(7). One commenter stated that
attended diesel equipment with a manual fire suppression system
presents no fire hazard. Another commenter suggested that unattended
diesel equipment should be prohibited. When diesel equipment is
operated in the primary escapeway and is properly attended and equipped
with a manual fire suppression system, the equipment operator can
immediately respond to a fire, and the safety afforded by the existing
standard is maintained. If the machine is shut off, however, attendance
is not necessary. When diesel equipment is to be operated unattended,
an automatic system is required to protect against fire.
One commenter stated that ``attended'' should be interpreted to
mean that the operator is on or within sight of the vehicle. Another
commenter urged that the standard be clarified to require that the
operator be at the controls of the equipment. For the purposes of
Sec. 75.380(f), by ``attended'' MSHA means that the equipment operator
would be on the mobile
[[Page 9814]]
equipment or immediately adjacent to the equipment and be capable of
activating the fire suppression system in the event of a fire.
The existing standard permits equipment to be in the escapeway for
purposes of transporting miners and materials and for maintaining the
escapeway but does not expressly prohibit the haulage of coal in the
primary escapeway. As a matter of clarification, the final rule
specifically prohibits coal haulage in the primary escapeway unless
incidental to cleanup and maintenance of the escapeway. One commenter
supported the proposed prohibition of coal haulage noting that coal
haulage would provide a ready source of fuel to a machinery-initiated
fire. Several commenters expressed a concern that incidental coal
haulage associated with cleanup and maintenance of the primary
escapeway would be prohibited under the proposed standard. Cleanup and
maintenance of the primary escapeway must be permitted. Therefore, the
final rule modifies the proposal to permit mobile equipment to haul
coal if incidental to cleanup and maintenance of the primary escapeway.
Paragraph (f)(3)(iii) prohibits compressors in the primary
escapeway except as provided in subparagraphs (f)(3)(iii) (A) through
(C). Subparagraph (A) allows compressors necessary to maintain the
escapeway in safe, travelable condition; (B) allows compressors that
are components of equipment such as locomotives and rock dusting
machines; and, (C) allows compressors of less than five horsepower due
to the limited fire hazard associated with their operation.
One commenter described an incident involving a compressor in an
intake airway, which was located in a fireproof enclosure but was
improperly ventilated. According to the commenter, smoke and
contaminants spread throughout the intake entry and reached the
section, which was then evacuated. This illustrates the importance of
providing adequate protection from the possible spread of smoke and
contaminants associated with compressor fires or overheating.
Paragraph (f)(3)(iv) of the final rule adds battery chargers to the
equipment included in the proposal that is permitted in the primary
escapeway provided they are located on or near a working section and
moved as the section advances or retreats. In all other respects,
paragraph (f)(3)(iv) of the final rule adopts the proposal. Under
paragraph (f)(3)(iv), underground transformer stations, battery
charging stations, substations, and rectifiers cannot be located in the
primary escapeway except: (A) where necessary to maintain the escapeway
in safe, travelable condition; and (B) battery chargers and rectifiers
and power centers with transformers that are either dry-type or contain
nonflammable liquid, provided they are located on or near a working
section and are moved as the section advances or retreats. The first
exception allows work to be performed in the primary escapeway to
assure its integrity. The second provides for the locations of the
described equipment at or near working sections if the equipment moves
with the section. Equipment at or near working sections will normally
be within a few crosscuts of the working face. In many cases,
particularly with battery chargers, there may be no practical
alternative to locating this equipment in the escapeway. In addition,
Sec. 75.340 provides additional protection when using underground
electrical equipment.
Paragraph (f)(3)(v) of the final rule adopts the proposal and
prohibits water pumps from being in the primary escapeway except as
provided under paragraphs (f)(3)(v)(A) through (f)(3)(v)(F). The pumps
that are permitted in the primary escapeway are the same ones that are
excepted from the requirements of Sec. 75.340 due to the low potential
for fire associated with their operation. They include: water pumps
necessary to maintain the escapeway in safe, travelable condition;
submersible pumps; permissible pumps and associated permissible
switchgear; pumps located on or near a working section that are moved
as the section advances or retreats; pumps installed in anthracite
mines; and small portable pumps. While the existing rule refers to the
electrical equipment described in Sec. 75.340 (a) and (b)(1), the final
rule, like the proposal, lists the affected equipment for the
convenience of the reader. Like Sec. 75.340, paragraph (f)(3)(v)
applies to water pumps and emulsion pumps when they are located on or
near the working section and are moved as the section advances or
retreats. One commenter agreed that pumps may be necessary to maintain
and rehabilitate the primary escapeway but suggested that a time limit
be placed on the length of time the pump is allowed to remain in the
escapeway. MSHA believes that specific conditions at the mine will
govern the amount of time required for any necessary pumping.
Therefore, MSHA has not included the suggestion in the final rule since
the decision relative to time must be made on a case-by-case basis, as
appropriate.
Paragraph (f)(4) of the final rule adopts MSHA's proposal with one
change. As proposed, paragraph (f)(4) would have required the use of
fire suppression systems on mobile equipment operated in the primary
escapeway, and would have allowed exceptions for continuous miners and
as provided in Sec. 75.380 (f)(5) and (f)(6). The final rule adds an
additional exception for emergency vehicles or ambulances as provided
in Sec. 75.380(f)(7). Unlike the existing standard, the final rule in
paragraph (f)(4) permits certain mobile equipment operated in the
primary escapeway to be protected with a manual fire suppression system
instead of an automatic system, provided it is attended by a person
trained in the use and operation of the fire suppression system. MSHA
believes that when a piece of equipment is operated in the primary
escapeway and is properly attended and equipped with a manual fire
suppression system, the equipment operator can immediately respond to
the situation, and the safety afforded by the existing standard is
maintained.
One commenter stated that no electrical, battery or diesel
equipment, or other equipment such as compressors should be allowed in
the primary escapeway, except for the purpose of maintenance of the
escapeway, and that this equipment should have an appropriate fire
suppression system. Because travel in the escapeway in certain mining
systems is essential for safety given the design of the mining system
used, the recommendation of the commenter has not been adopted in the
final rule. Instead, the final rule provides that certain types of
mining equipment can be operated in the primary escapeway provided the
safety precautions set out in the standard are followed. One commenter
stated that the rule should only apply to mobile equipment which is
operated in the primary escapeway, since equipment not operating
presents little or no hazard. MSHA agrees and has incorporated this
clarification into the final rule.
Commenters indicated that it is sometimes necessary to withdraw
face equipment, such as continuous miners, roof bolting machines and
shuttle cars, into the primary escapeway for a short distance beyond
the loading point. The equipment is sometimes parked and left there on
down shifts or between shifts. MSHA notes that, as clarified, the final
rule does not prohibit this practice. Because the equipment would be
attended when operated and is provided with manual fire suppression,
the
[[Page 9815]]
equipment may be operated in the primary escapeway.
Following promulgation of the existing rule, some persons construed
the requirement for an automatic fire suppression system to apply to
electric face equipment. As explained in the preamble to the proposal,
this was not the intent of MSHA. To clarify its intent, MSHA issued
Program Policy Letter No. P92-V-4 on November 16, 1992, addressing the
operation and location of equipment in primary escapeways. Under
existing regulations in Subpart L--Fire Protection, face equipment is
required to be protected by a manual fire suppression system. The final
rule recognizes and generally conforms with this requirement. Other
than for an exception to permit a situation such as the movement of
continuous mining machines between sections without a continuous water
supply, the final rule requires that when face machinery, equipped with
a manual fire suppression system, is operated in the primary escapeway,
it must be attended by a person trained in the proper function and use
of the fire suppression system. The continuous mining machine exception
recognizes that the fire suppression system for the continuous mining
machine often relies on a water supply that may be impracticable to
provide during equipment moves.
The final rule requires in paragraph (f)(4) that with exceptions
for continuous mining machines and as provided in paragraphs (f)(5),
(f)(6), and (f)(7), each piece of mobile equipment operated in primary
escapeways shall: (1) be equipped with manually operated fire
suppression systems installed in compliance with Secs. 75.1107-3
through 75.1107-16 and be attended continuously; or (2) be equipped
with an automatic fire suppression system that is capable of both
automatic and manual activation and installed in compliance with
Secs. 75.1107-3 through 75.1107-16. Fire suppression systems which were
installed to meet the 1992 rule will continue to be accepted.
Under paragraph (f)(5) of the final rule, personnel carriers and
small personnel conveyances designed and used solely for the
transportation of personnel and small hand tools can be operated in the
primary escapeway if either of the requirements under paragraphs (i) or
(ii) are met. This class of equipment would not include diesel-powered
pickup trucks, for example, which would be governed by paragraph
(f)(4). Paragraph (i) requires a multipurpose dry chemical type
automatic fire suppression system capable of both manual and automatic
activation. Paragraph (ii) provides an alternative for a class of
small, battery powered, golf cart type, equipment used for transport of
persons and small hand tools. In this case, fire extinguishers may be
used in lieu of a fire suppression system.
Commenters questioned the need for automatic systems on the class
of equipment consisting of small, battery powered, golf cart type
equipment. One commenter suggested that a manual fire suppression
system should be accepted. After a review of the issue, MSHA has
concluded that some types of mobile equipment present a very limited
fire hazard. In the case of small, battery operated, golf cart type,
conveyances designed and used for the transport of personnel and small
hand tools, considering the limited hazard, a trained operator provided
with two 10 pound multi-purpose dry chemical fire extinguishers is
equivalent in protection to a fire suppression system. Accordingly, as
an alternative under paragraph (ii), small battery powered, golf cart
type, equipment may be operated in the primary escapeway if provided
with two 10 pound multi-purpose dry chemical fire extinguishers. Unlike
diesel powered equipment, the golf cart type of equipment is shut off
when not operating and, therefore, attendance is not an issue. The 10
pound units are standard size extinguishers and are appropriate for the
equipment involved.
The system used in accordance with paragraph (i) must be suitable
for the intended application and listed or approved by a nationally
recognized independent testing laboratory. The language was proposed as
two paragraphs but has been combined in the final rule under paragraph
(i) and an alternative has been added as paragraph (ii). The types of
machinery which fall under paragraph (f)(5) are not required to meet
the additional requirements of Secs. 75.1107-3 through 75.1107-16. For
example, it would be impractical and would not enhance safety to apply
the minimum dry chemical poundage requirements of Sec. 75.1107-9 to
small equipment designed and used solely for personnel and small hand
tools.
During informational meetings, it was suggested that the term ``dry
chemical'' would be more accurate and appropriate than the term ``dry
powder'' used in the existing standard. Like the proposal, the final
rule adopts this language. MSHA received no comments on this proposed
revision
Paragraph (f)(6) of the final rule provides an exception to the
general requirement and allows mobile equipment not provided with a
fire suppression system to operate in the primary escapeway if no
persons are inby other than persons directly engaged in the use or
moving of the equipment. This provision of the final rule allows for
the necessary movement of face equipment, such as between sections.
One commenter stated that the exemption provided in (f)(6) should
be expanded to allow equipment that does not have a fire suppression
system to be relocated provided monitoring equipment is utilized for
carbon monoxide or smoke and two-way communication is available to
notify appropriate persons. The final rule does not adopt this
suggestion. During moves, equipment is often laboring at maximum
capacity and there can be several machines operating simultaneously.
Under these conditions, equipment fires can develop quickly and the
products of combustion would be carried to inby workers by the
ventilating current. By permitting only workers who are directly
engaged in the operation or movement of the equipment, the final rule
prevents other workers from being exposed to the hazards of a fire on
the equipment being moved. Workers operating or engaged in moving the
equipment will be in a position to quickly identify the hazard and take
necessary action.
Another commenter objected to the provision stating that fire
suppression should be required on all equipment in the primary
escapeway. This suggestion has not been adopted in the final rule. MSHA
does not agree that fire suppression is needed when no persons are inby
or downstream of the equipment being moved. MSHA has concluded that
either these machines should be equipped with fire suppression, or fire
extinguishers as in (f)(5)(ii), or no persons should be inby the
location where the equipment is being operated except those persons
directly engaged in the operation or movement of the equipment.
Another commenter suggested that the wording of (f)(6) could be
read to allow miners to work on a longwall face while equipment not
equipped with fire suppression is operated anywhere in the primary
escapeway. This is not permitted by the standard. By including the
phrase, ``. . . except those persons directly engaged in using or
moving the equipment'', the persons affected are only those persons in
the immediate vicinity of the machine. With no persons working inby,
the use of machinery without a fire suppression system would not expose
persons to the hazard of toxic gases and fumes from a fire on the
equipment. The language
[[Page 9816]]
also would not permit persons to operate mobile equipment without a
fire suppression system in the primary escapeway while miners are
downstream working on a longwall face. The controlling factor is
whether the persons inby are directly engaged in using or moving that
particular piece of equipment. If they are, and no one else is inby,
the equipment may be operated without a fire suppression system. For
example, when moving a longwall shield, no one would be permitted to be
inby the machine being used to move the shield if the machine is not
provided with a fire suppression system except those persons moving the
shield. This would include miners operating other pieces of equipment
to move other shields.
Paragraph (f)(7) modifies the existing rule to include a new
exemption to the requirement that mobile equipment operated in primary
escapeways have a fire suppression system. Paragraph (f)(7) permits
mobile equipment designated and used only as emergency vehicles or
ambulances to operate in the primary escapeway without fire suppression
systems. It was suggested to MSHA that certain types of emergency
equipment, such as diesel powered ambulances, should be exempt from the
requirements for fire suppression systems. Comments were received
suggesting that ambulances should be exempt because space is extremely
limited on these vehicles and because they are used infrequently. MSHA
recognizes the potential benefit in the use of this type of equipment.
Another commenter objected, foreseeing potential abuses of the
exemption by mine operators who would designate equipment as ambulances
but use it as ordinary equipment. The final rule permits emergency
vehicles to be operated in the primary escapeway without fire
suppression systems only when this equipment is used for medical
emergencies.
This existing rule requires in paragraph (i)(2) that mechanical
escape facilities be provided and maintained for, ``. . . each slope
that is part of a designated escapeway that is either inclined 18
degrees or more from the horizontal or is inclined 9 degrees or more
from the horizontal and is greater than 1,000 feet in length.'' During
informational meetings, MSHA became aware of a concern that existing
paragraph (i)(2) would permit slopes of significant length and
inclination to exist without any mechanical escape facilities. An
example would be a slope of 900 feet inclined less than 18 degrees from
the horizontal. It was suggested that such a slope could be
particularly difficult for passage of injured persons under cold and
icy conditions if mechanical escape facilities were not provided. In
light of this concern, MSHA proposed to require that mechanical escape
facilities be provided and maintained from the coal seam to the surface
for each slope that is part of a designated escapeway and is inclined
more than 9 degrees from the horizontal. The final rule adopts the
proposal.
One commenter objected to proposed paragraph (i)(2) indicating that
facilities are unnecessary in low angle slopes which are of short
length. Other commenters believed that the 1992 standard was
appropriate. Another commenter indicated support for the proposal as a
way to enable persons to escape quickly in an emergency. This commenter
also noted that escape can be very difficult in icy winter conditions
in some slopes. After consideration of the comments received, MSHA
concludes that the proposal was appropriate and the final rule adopts
this aspect of the proposal.
One commenter suggested that proposed paragraph (i)(2) could be
interpreted as requiring mechanical escape facilities for slopes that
occur naturally underground. It was not MSHA's intent to apply
paragraph (i)(2) to slopes other than from the coal seam to the
surface. The final rule clarifies this and requires that mechanical
escape facilities be provided for each slope from the coal seam to the
surface that is part of a designated escapeway and is inclined more
than 9 degrees from the horizontal.
Like the proposal, the final rule in paragraph(d)(5) revises the
existing language dealing with the location of escapeways. It provides
that escapes shall be located to follow the most direct, safe and
practical route to the nearest mine opening suitable for the safe
evacuation of miners. A question arose during an informational meeting
as to whether MSHA intended that the existing rule eliminate the
requirement that escapeways be routed to the ``nearest mine opening.''
It was not MSHA's intent to change this requirement from the previous
standard. The existing requirement that the escapeway follow the most
direct route to the surface would, in fact, require the route to go to
the nearest mine opening. However, to eliminate any confusion that may
exist, the final rule revises paragraph (d)(5) and adopts language
similar to that in previous regulation, Sec. 75.1704-2(a), that is,
that the escapeway must follow the most direct, safe and practical
route to the nearest mine opening suitable for the safe evacuation of
miners.
One commenter stated that escapeways should not be permitted to
pass an opening to be routed to a more distant opening. Another
commenter stated that the nearest mine opening may not always be the
safest due to roof conditions or other factors. MSHA acknowledges that
the nearest mine opening may not always be the safest route to the
surface. A number of factors affect whether or not the safest, most
direct, practical route has been selected. These factors include roof
conditions, travel height, fan location, physical dimensions of the
mine opening, and similar considerations. For example, if bad roof
conditions are present along the shortest direct route and those roof
conditions are beyond reasonable control, then an alternate ``safe''
route designated by the mine operator may be appropriate. However, the
presence of roof falls does not necessarily indicate that the
passageway would not be suitable for evacuation if it is reasonable to
rehabilitate the area. By way of another example, where coal seam
thickness varies to the extreme, the shortest route may be through
lower coal, making travel relatively slow and difficult. An alternate
route through a high passageway may permit easier travel. Such an
alternate route, although longer, may be more practical and therefore
may be more appropriate. Similarly, there can be instances where the
``nearest mine opening'' may not be suitable for safe evacuation of
miners. For example, an old mine shaft may not be safe for travel
because of badly deteriorated conditions, such as a deteriorated shaft
lining or deteriorated timbers, even though the shaft is still suitable
for mine ventilation purposes.
As with the existing standard, mine development projections do not
have to be altered to provide additional rooms, entries, or crosscuts
for the sole purpose of providing a passageway to the nearest mine
opening. However, the construction of ventilation controls such as
stoppings, overcasts and undercasts, or the installation of an escape
facility may be required to provide the most direct, safe and practical
route to the surface.
One commenter suggested that MSHA should require an escapeway plan
to be approved by the MSHA district manager to assure the most direct
route to the surface. Existing standards require that escapeways be
shown on the ventilation map. In addition, as with other regulations,
inspectors assess whether escapeways follow the most direct, safe and
practical route to the surface during each regular inspection.
Accordingly, MSHA does not believe that an additional plan is
necessary.
[[Page 9817]]
Existing paragraph (f) establishes the requirements for ventilation
of the primary escapeway and identifies which equipment can be operated
in the primary escapeway and the fire suppression requirements for this
equipment. The final rule, like the proposal, modifies paragraph (f) to
explicitly identify the equipment that is not permitted in the primary
escapeway and to specify the types of fire suppression systems that are
to be used and the conditions under which each is to be used on
equipment permitted in the primary escapeway. This is done by replacing
existing paragraphs (f)(1) and (f)(2) with paragraphs (f)(1) through
(f)(7) in the final.
Existing paragraph (f)(1) requires that one escapeway that is
ventilated with intake air be designated as the primary escapeway and
prohibits certain equipment from being used in the primary escapeway in
areas developed after November 15, 1992. Further, paragraph (f)(1)
requires fire suppression systems on mobile equipment that is operated
in the primary escapeway. The final rule transfers the part of existing
paragraph (f)(1) that specifies the area of the primary escapeway
affected to paragraph (f)(2).
The existing rule limited the installation or use of certain
equipment in areas of the primary escapeway developed after November
15, 1992. Paragraph (f)(2) of the final rule modifies the existing rule
for clarity and expands the application of certain requirements
contained in paragraphs (f)(3) through (f)(7) to the entire primary
escapeway except those areas of the primary escapeway developed prior
to March 30, 1970 where separation of the primary escapeway from the
belt and trolley haulage entries did not exist as of November 16, 1992.
For areas of mines developed after September 15, 1992, (those areas
covered by the existing rule) the provisions of paragraphs (f)(3)
through (f)(7) will be effective as of March 11, 1997. For other areas
covered by the rule, MSHA has provided for a 1 year phase in period to
allow mine operators time to effectively plan and implement the
necessary changes. The phase in period applies to areas of a primary
escapeway developed between March 30, 1970 and November 16, 1992, and
to areas of the primary escapeway developed prior to March 30, 1970
where separation of the belt and trolley haulage entries from the
primary escapeway existed prior to November 16, 1992.
Paragraph (f)(3) prohibits certain equipment from the primary
escapeway. Paragraphs (f)(4) and (f)(5) deal with fire protection for
mobile equipment that is permitted in the primary escapeway and
paragraph (f)(6) addresses a specific circumstance when mobile
equipment may operate in a primary escapeway without a fire suppression
system. Paragraph (f)(7), a provision added to the proposed language in
response to comments, allows the use of designated emergency vehicles
or ambulances in the primary escapeway.
One commenter suggested that the final rule should not provide an
exception for all areas where separation of the primary escapeway from
the belt and trolley haulage entry does not exist. The commenter
recognized, however, that Congress granted an exemption from separation
requirements for areas of the primary escapeway developed prior to
March 30, 1970, the effective date of the Act. The intent of the
proposal was to provide an exemption from the requirements of proposed
paragraphs (f)(3) through (f)(6) for these same areas. The commenter
points out that the proposal would have extended the exemption to other
areas of the primary escapeway where, for one reason or another,
separation did not exist on November 16, 1992, the effective date of
the existing rule. The final rule modifies the proposal to clarify that
the exemption only applies to those areas of the escapeway that were
developed prior to March 30, 1970 and where separation did not exist on
November 16, 1992.
Another commenter correctly interpreted proposed paragraph (f)(2)
as extending the requirement that limits the types of equipment
permitted in primary escapeways to areas of the mine developed prior to
November 16, 1992. The commenter stated that the proposed regulation
would pose great cost to the industry with no appreciable safety
benefit derived. A review of the fire history relative to both
stationary and mobile equipment indicates that fires can and do occur
on this equipment. Mobile equipment by design is intended to provide
flexibility in movement and is capable of operating anywhere in the
mine. Although the accident reports do not specify whether the mobile
equipment that caught fire was in the primary escapeway when the fire
started, it is reasonable to conclude that at least some of these fires
did occur in the primary escapeway. MSHA continues to believe that
given the importance of the primary escapeway to the safety of miners,
the extension of the requirements for operation of equipment in the
primary escapeway is appropriate.
Paragraph (f)(3) lists the equipment that is not permitted in the
primary escapeway. Under paragraph(f)(3)(i) of the final rule,
operating diesel equipment without an automatic fire suppression system
is prohibited in the primary escapeway unless it is attended, except as
provided in paragraphs (f)(6) and (f)(7). One commenter stated that
attended diesel equipment with a manual fire suppression system
presents no fire hazard. Another commenter suggested that unattended
diesel equipment should be prohibited. When diesel equipment is
operated in the primary escapeway and is properly attended and equipped
with a manual fire suppression system, the equipment operator can
immediately respond to a fire, and the safety afforded by the existing
standard is maintained. If the machine is shut off, however, attendance
is not necessary. When diesel equipment is to be operated unattended,
an automatic system is required to protect against fire.
One commenter stated that ``attended'' should be interpreted to
mean that the operator is on or within sight of the vehicle. Another
commenter urged that the standard be clarified to require that the
operator be at the controls of the equipment. For the purposes of
Sec. 75.380(f), by ``attended'' MSHA means that the equipment operator
would be on the mobile equipment or immediately adjacent to the
equipment and be capable of activating the fire suppression system
immediately in the event of a fire.
The existing standard permits equipment to be in the escapeway for
purposes of transporting miners and materials and for maintaining the
escapeway but does not expressly prohibit the haulage of coal in the
primary escapeway. As a matter of clarification, the final rule
specifically prohibits coal haulage in the primary escapeway unless
incidental to cleanup and maintenance of the escapeway. One commenter
supported the proposed prohibition of coal haulage noting that coal
haulage would provide a ready source of fuel to a machinery-initiated
fire. Several commenters expressed a concern that incidental coal
haulage associated with cleanup and maintenance of the primary
escapeway would be prohibited under the proposed standard. Cleanup and
maintenance of the primary escapeway must be permitted. Therefore, the
final rule modifies the proposal to permit mobile equipment to haul
coal if incidental to cleanup and maintenance of the primary escapeway.
Paragraph (f)(3)(iii) prohibits compressors in the primary
escapeway except as provided in subparagraphs (f)(3)(iii) (A) through
(C). Subparagraph
[[Page 9818]]
(A) allows compressors necessary to maintain the escapeway in safe,
travelable condition; (B) allows compressors that are components of
equipment such as locomotives and rock dusting machines; and, (C)
allows compressors of less than five horsepower due to the limited fire
hazard associated with their operation.
One commenter described an incident involving a compressor in an
intake airway, which was located in a fireproof enclosure but was
improperly ventilated. According to the commenter, smoke and
contaminants spread throughout the intake entry and reached the
section, which was then evacuated. This illustrates the importance of
providing adequate protection from the possible spread of smoke and
contaminants associated with compressor fires or overheating.
Paragraph (f)(3)(iv) of the final rule adds battery chargers to the
equipment included in the proposal that is permitted in the primary
escapeway provided it is located on or near a working section and is
moved as the section advances or retreats. In all other respects,
paragraph (f)(3)(iv) of the final rule adopts the proposal. Under
paragraph (f)(3)(iv), underground transformer stations, battery
charging stations, substations, and rectifiers cannot be located in the
primary escapeway except: (A) where necessary to maintain the escapeway
in safe, travelable condition; and (B) battery chargers and rectifiers
and power centers with transformers that are either dry-type or contain
nonflammable liquid, provided they are located on or near a working
section and are moved as the section advances or retreats. The first
exception allows work to be performed in the primary escapeway to
assure its integrity. The second provides for the locations of the
described equipment at or near working sections if the equipment moves
with the section. Equipment at or near working sections will normally
be within a few crosscuts of the working face. In many cases,
particularly with battery chargers, there may be no practical
alternative to locating this equipment in the escapeway. In addition,
Sec. 75.340 provides additional protection when using underground
electrical equipment.
Paragraph (f)(3)(v) of the final rule adopts the proposal and
prohibits water pumps from being in the primary escapeway except as
provided under paragraphs (f)(3)(v)(A) through (f)(3)(v)(F). The pumps
that are permitted in the primary escapeway are the same ones that are
excepted from the requirements of Sec. 75.340 due to the low potential
for fire associated with their operation. They include: water pumps
necessary to maintain the escapeway in safe, travelable condition;
submersible pumps; permissible pumps and associated permissible
switchgear; pumps located on or near a working section that are moved
as the section advances or retreats; pumps installed in anthracite
mines; and small portable pumps. While the existing rule refers to the
electrical equipment described in Sec. 75.340 (a) and (b)(1), the final
rule, like the proposal, lists the affected equipment for the
convenience of the reader. Like Sec. 75.340, paragraph (f)(3)(v)
applies to water pumps and emulsion pumps when they are located on or
near the working section and are moved as the section advances or
retreats. One commenter agreed that pumps may be necessary to maintain
and rehabilitate the primary escapeway but suggested that a time limit
be placed on the length of time the pump is allowed to remain in the
escapeway. MSHA believes that specific conditions at the mine will
govern the amount of time required for any necessary pumping.
Therefore, MSHA has not included the suggestion in the final rule since
the decision relative to time must be made on a case-by-case basis, as
appropriate.
Paragraph (f)(4) of the final rule adopts MSHA's proposal with one
change. As proposed, paragraph (f)(4) would have required the use of
fire suppression systems on mobile equipment operated in the primary
escapeway, and would have allowed exceptions for continuous miners and
as provided in Sec. 75.380(f)(5)and (f)(6). The final rule adds an
additional exception for emergency vehicles or ambulances as provided
in Sec. 75.380(f)(7). Unlike the existing standard, the final rule in
paragraph (f)(4) permits certain mobile equipment operated in the
primary escapeway to be protected with a manual fire suppression system
instead of an automatic system, provided it is continuously attended by
a person trained in the use and operation of the fire suppression
system. MSHA believes that when a piece of equipment is operated in the
primary escapeway and is properly attended and equipped with a manual
fire suppression system, the equipment operator can immediately respond
to the situation, and the safety afforded by the existing standard is
maintained.
One commenter stated that no electrical, battery or diesel
equipment, or other equipment such as compressors should be allowed in
the primary escapeway, except for the purpose of maintenance of the
escapeway, and that this equipment should have an appropriate fire
suppression system. Because travel in the escapeway in certain mining
systems is essential for safety given the design of the mining system
used, the recommendation of the commenter has not been adopted in the
final rule. Instead, the final rule provides that certain types of
mining equipment can be operated in the primary escapeway provided the
safety precautions set out in the standard are followed. One commenter
stated that the rule should only apply to mobile equipment which is
operated in the primary escapeway, since equipment not operating
presents little or no hazard. MSHA agrees and has incorporated this
clarification into the final rule.
Commenters indicated that it is sometimes necessary to withdraw
face equipment, such as continuous miners, roof bolting machines and
shuttle cars, into the primary escapeway for a short distance beyond
the loading point. The equipment is sometimes parked and left there on
down shifts or between shifts. MSHA notes that, as clarified, the final
rule does not prohibit this practice. Because the equipment would be
attended when operated and is provided with manual fire suppression,
the equipment may be operated in the primary escapeway.
Following promulgation of the existing rule, some persons construed
the requirement for an automatic fire suppression system to apply to
electric face equipment. As explained in the preamble to the proposal,
this was not the intent of MSHA. To clarify its intent, MSHA issued
Program Policy Letter No. P92-V-4 on November 16, 1992, addressing the
operation and location of equipment in primary escapeways. Under
existing regulations in Subpart L--Fire Protection, face equipment is
required to be protected by a manual fire suppression system. The final
rule recognizes and generally conforms with this requirement. Other
than for an exception to permit a situation such as the movement of
continuous mining machines between sections without a continuous water
supply, the final rule requires that when face machinery, equipped with
a manual fire suppression system, is operated in the primary escapeway,
it must be attended by a person trained in the proper function and use
of the fire suppression system. The continuous mining machine exception
recognizes that the fire suppression system for the continuous mining
machine often relies on a water supply that may be impracticable to
provide during equipment moves.
[[Page 9819]]
The final rule requires in paragraph (f)(4) that with exceptions
for continuous mining machines and as provided in paragraphs (f)(5),
(f)(6), and (f)(7), each piece of mobile equipment operated in primary
escapeways shall: (1) be equipped with manually operated fire
suppression systems installed in compliance with Secs. 75.1107-3
through 75.1107-16 and be attended continuously; or (2) be equipped
with an automatic fire suppression system that is capable of both
automatic and manual activation and installed in compliance with
Secs. 75.1107-3 through 75.1107-16.
Under paragraph (f)(5) of the final rule, personnel carriers and
small personnel conveyances designed and used solely for the
transportation of personnel and small hand tools can be operated in the
primary escapeway if either of the requirements under paragraphs (i) or
(ii) are met. Paragraph (i) requires a multipurpose dry chemical type
automatic fire suppression system capable of both manual and automatic
activation. Paragraph (ii) provides an alternative for a class of
small, battery powered, golf cart type, equipment used for transport of
persons and small hand tools. In this case, fire extinguishers may be
used in lieu of a fire suppression system.
Commenters questioned the need for automatic systems on the class
of equipment consisting of small, battery powered, golf cart type
equipment. One commenter suggested that a manual fire suppression
system should be accepted. After a review of the issue, MSHA has
concluded that some types of mobile equipment present a very limited
fire hazard. In the case of small, battery operated, golf cart type,
conveyances designed and used for the transport of personnel and small
hand tools, considering the limited hazard, a trained operator provided
with two 10 pound multi-purpose dry chemical fire extinguishers is
equivalent in protection to a fire suppression system. Accordingly, as
an alternative under paragraph (ii), small battery powered, golf cart
type, equipment may be operated in the primary escapeway if provided
with two 10 pound multi-purpose dry chemical fire extinguishers. Unlike
diesel powered equipment, the golf cart type of equipment is shut off
when not operating and, therefore, attendance is not an issue. The 10
pound units are standard size extinguishers and are appropriate for the
equipment involved.
The system used in accordance with paragraph (i) must be suitable
for the intended application and listed or approved by a nationally
recognized independent testing laboratory. The language was proposed as
two paragraphs but has been combined in the final rule under paragraph
(i) and an alternative has been added as paragraph (ii). The types of
machinery which fall under paragraph (f)(5) are not required to meet
the additional requirements of Secs. 75.1107-3 through 75.1107-16. For
example, it would be impractical and would not enhance safety to apply
the minimum dry chemical poundage requirements of Sec. 75.1107-9 to
small equipment designed and used solely for personnel and small hand
tools.
During informational meetings, it was suggested that the term ``dry
chemical'' would be more accurate and appropriate than the term ``dry
powder'' used in the existing standard. Like the proposal, the final
rule adopts this language. MSHA received no comments on this proposed
revision.
Paragraph (f)(6) of the final rule provides an exception to the
general requirement and allows mobile equipment not provided with a
fire suppression system to operate in the primary escapeway if no
persons are inby other than persons directly engaged in the use or
moving of the equipment. This provision of the final rule allows for
the necessary movement of face equipment, such as between sections.
One commenter stated that the exemption provided in (f)(6) should
be expanded to allow equipment that does not have a fire suppression
system to be relocated provided monitoring equipment is utilized for
carbon monoxide or smoke and two-way communication is available to
notify appropriate persons. The final rule does not adopt this
suggestion. During moves, equipment is often laboring at maximum
capacity and there can be several machines operating simultaneously.
Under these conditions, equipment fires can develop quickly and the
products of combustion would be carried to inby workers by the
ventilating current. By permitting only workers who are directly
engaged in the operation or movement of the equipment, the final rule
prevents other workers from being exposed to the hazards of a fire on
the equipment being moved. Workers operating or engaged in moving the
equipment will be in a position to quickly identify the hazard and take
necessary action.
Another commenter objected to the provision stating that fire
suppression should be required on all equipment in the primary
escapeway. This suggestion has not been adopted in the final rule. MSHA
does not agree that fire suppression is needed when no persons are inby
or downstream of the equipment being moved. MSHA has concluded that
either these machines should be equipped with fire suppression, or fire
extinguishers as in (f)(5)(ii), or no persons should be inby the
location where the equipment is being operated except those persons
directly engaged in the operation or movement of the equipment.
Another commenter suggested that the wording of (f)(6) could be
read to allow miners to work on a longwall face while equipment not
equipped with fire suppression is operated anywhere in the primary
escapeway. This is not permitted by the standard. By including the
phrase, ``* * * except those persons directly engaged in using or
moving the equipment'', the persons affected are only those persons in
the immediate vicinity of the machine. With no persons working inby,
the use of machinery without a fire suppression system would not expose
persons to the hazard of toxic gases and fumes from a fire on the
equipment. The language also would not permit persons to operate mobile
equipment without a fire suppression system in the primary escapeway
while miners are downstream working on a longwall face. The controlling
factor is whether the persons inby are directly engaged in using or
moving that particular piece of equipment. If they are, and no one else
is inby, the equipment may be operated without a fire suppression
system. For example, when moving a longwall shield, no one would be
permitted to be inby the machine being used to move the shield if the
machine is not provided with a fire suppression system except those
persons moving the shield. This would include miners operating other
pieces of equipment to move other shields.
Paragraph (f)(7) modifies the existing rule to include a new
exemption to the requirement that mobile equipment operated in primary
escapeways have a fire suppression system. Paragraph (f)(7) permits
mobile equipment designated and used only as emergency vehicles or
ambulances to operate in the primary escapeway without fire suppression
systems. It was suggested to MSHA that certain types of emergency
equipment, such as diesel powered ambulances, should be exempt from the
requirements for fire suppression systems. Comments were received
suggesting that ambulances should be exempt because space is extremely
limited on these vehicles and because they are used infrequently. MSHA
recognizes the potential benefit in the use of this type of equipment.
Another commenter objected, foreseeing potential abuses of
[[Page 9820]]
the exemption by mine operators who would designate equipment as
ambulances but use it as ordinary equipment. The final rule permits
emergency vehicles to be operated in the primary escapeway without fire
suppression systems only when this equipment is used only for medical
emergencies.
This existing rule requires in paragraph (i)(2) that mechanical
escape facilities be provided and maintained for, ``. . . each slope
that is part of a designated escapeway that is either inclined 18
degrees or more from the horizontal or is inclined 9 degrees or more
from the horizontal and is greater than 1,000 feet in length.'' During
informational meetings, MSHA became aware of a concern that existing
paragraph (i)(2) would permit slopes of significant length and
inclination to exist without any mechanical escape facilities. An
example would be a slope of 900 feet inclined less than 18 degrees from
the horizontal. It was suggested that such a slope could be
particularly difficult for passage of injured persons under cold and
icy conditions if mechanical escape facilities were not provided. In
light of this concern, MSHA proposed to require that mechanical escape
facilities be provided and maintained from the coal seam to the surface
for each slope that is part of a designated escapeway and is inclined
more than 9 degrees from the horizontal. The final rule adopts the
proposal.
One commenter objected to proposed paragraph (i)(2) indicating that
facilities are unnecessary in low angle slopes which are of short
length. Other commenters believed that the 1992 standard was
appropriate. Another commenter indicated support for the proposal as a
way to enable persons to escape quickly in an emergency. This commenter
also noted that escape can be very difficult in icy winter conditions
in some slopes. After consideration of the comments received, MSHA
concludes that the proposal was appropriate and the final rule adopts
this aspect of the proposal.
One commenter suggested that proposed paragraph (i)(2) could be
interpreted as requiring mechanical escape facilities for slopes that
occur naturally underground. It was not MSHA's intent to apply
paragraph (i)(2) to slopes other than from the coal seam to the
surface. The final rule clarifies this and requires that mechanical
escape facilities be provided for each slope from the coal seam to the
surface that is part of a designated escapeway and is inclined more
than 9 degrees from the horizontal.
Section 75.382 Mechanical Escape Facilities
Because an escapeway route can sometimes be very long, the most
safe, direct and practical route to the surface can sometimes involve
the use of a mechanical escape device such as an automatic elevator or
similar, but less sophisticated, device. Section 75.382 contains the
requirements for mechanical escape facilities installed in escapeways
under Sec. 75.380 and Sec. 75.381. The final rule contains a new
requirement for certification of escape facility examinations, proposed
as paragraph (g). The final rule does not retain the other proposed
changes, paragraphs (h) and (i), that would have added recordkeeping
and countersigning requirements.
Under paragraph (g) of the final rule, the designated examiner
certifies by date, time, and initials that the mechanical escape
facilities examination required by paragraph Sec. 75.382(c) was
performed. The certification must be located at or near the facility
examined. Certification has long been an accepted practice in the
mining industry for assuring that a required examination has been
completed. One commenter agreed that certification is necessary and
supported the revision. The commenter indicated that the facilities are
often designated as escapeways and therefore there should be some
assurance that the facilities have been examined and are ready for use.
Also, in the case of mechanical escape facilities, if certification is
not provided, precious time could be lost as the escape facility is
tested prior to use to determine if it is functional and safe.
Under the proposed paragraphs (h) and (i), a record would have had
to be made of the examination of the escape facility performed in
accordance with Sec. 75.382 (c). The results of the examination would
be included in a record, including any deficiency found along with the
corrective actions taken to correct the condition. One commenter
supported the revision requiring records of deficiencies found during
examinations as well as a record of corrective actions. Other
commenters objected to additional records, noting that they would not
enhance safety. After review of the comments, MSHA has concluded that
certification will achieve the intended objective of assuring the
safety of mechanical escape. Accordingly, the recordkeeping
requirements proposed as paragraphs (h) and (i) are omitted from the
final rule.
One commenter stated that many companies utilize mobile escape
facilities to cover more than one mine if the mines are located in
close proximity. The commenter believed that such an arrangement was
not considered in the countersigning provisions of the proposal and
stated, ``The effort required to go to each mine every week and track
down the mine foreman would be burdensome and unnecessary.'' Paragraph
(c) of the existing rule requires a weekly examination and a weekly
test in which the hoist must be run through one complete cycle of
operation to determine that it is operating properly. The final rule
requires certification to be completed by the examiner. As indicated
above, MSHA has concluded that certification will achieve the intended
objective of assuring that the examinations have been conducted.
Additional comments were received recommending further
modifications and additions to Sec. 75.382. For example, a commenter
recommended 2-way communication capability, with supplies and a holding
area at the escape facility. These types of comments related to issues
outside the scope of the rulemaking and were not addressed. Another
commenter would have MSHA reinstate language from an earlier rule,
alleging a reduction in protection. MSHA does not believe that there is
a reduction in protection. Also, the final rule did not propose to
change the existing requirement that the commenter claimed reduced
protection, i.e., that a person trained to operate the mechanical
escape facility always shall be available. MSHA notes that this issue
is outside the scope of the rulemaking.
Section 75.383 Escapeway Maps and Drills
When a fire, explosion or other emergency necessitates an immediate
evacuation of a mine the designated route for miners to leave the mine
is the escapeway. During a mine fire, passageways, even those
designated as escapeways, can become smoke filled and the ability to
see can be drastically reduced. Therefore, it is vitally important that
miners know the route of travel through the escapeway. Section 75.383
provides for the posting of escapeway maps so that they are available
for miners to study and use during an emergency, if necessary. Section
75.383 also provides for miners to be trained in the escape route
through escapeway drills. Escapeway drills in mines are similar to fire
drills in schools and high rise buildings.
Existing paragraphs (a) and (b)(1) of Sec. 75.383 deal with the
escapeway map and drill requirements in areas where mechanized mining
equipment is being
[[Page 9821]]
installed or removed. Based on comments received, the final rule
contains 2 revisions to the proposal. The first allows the mine map to
be readily accessible as an alternative to posting. The second requires
that miners who are underground when any change is made to the
escapeway map be immediately notified of the change. These revisions to
the proposal are discussed below.
One commenter supported the requirements of (a) and (b)(1) noting
the hazards and activities where mechanized mining equipment is being
installed or removed. Another commenter stated that the requirement
that the map be ``posted'' is impractical in some mines. The commenter
stated that the rule should simply require that the map be maintained
on the section to allow the map to be maintained in a map tube, or be
covered. The commenter also indicated that a map tube could aid miners
in a rapid escape since the map and tube could easily be taken with the
miners during the escape. MSHA agrees that the maintenance of a posted
map could be difficult in some conditions such as in wet or very low
height mines. Accordingly, the final rule provides an option wherein
the map may be either posted or be maintained in a location readily
accessible to all miners. In specifying ``readily accessible'' MSHA
intends that all miners be made aware of the map location and have
access to review the map at any time. As an example, a map secured in a
locked tool chest would not be acceptable.
One commenter objected to paragraph (a) in two respects. First,
according to the commenter, the standard does not require maps to show
the revised escapeway routes until the end of the shift on which the
changes are made. The commenter believes that changes are projected in
advance and therefore the maps should be updated immediately. Second,
the commenter indicated that the requirement that miners must be
informed of the changes before entering the mine does not address
affected miners already underground. Many changes within escapeways are
not known or planned well in advance. Often, such revisions are in
response to changing conditions underground. MSHA does not believe that
allowing a portion of one shift is an excessive amount of time to
update the maps. MSHA does agree, however, that changes to the
escapeways should be immediately brought to the attention of all miners
who are underground at the time of a change. Accordingly, the final
rule specifies that all affected miners already underground must be
immediately notified of the change. This will assure that all affected
miners are aware of the change from the time the change is implemented.
While agreeing that each miner's familiarity with escapeways is
important, one commenter stated that requiring travel by foot in the
escapeways could cause undue physical stress to some miners in low or
steeply pitching seams. The commenter continued that the desired result
could be obtained by requiring full participation in drills where
transportation is provided and full participation in drills where
transportation is not provided, unless that escapeway is equipped with
a continuous, directional life line. MSHA notes that the standard does
not require travel on foot. Transportation may be used for escapeway
drills provided that the purpose of the standard can be achieved. That
purpose is to assure that miners are familiar with the escapeway routes
and, as specified in (b)(4), before or during practice escapeway
drills, miners shall be informed of the locations of fire doors, check
curtains, changes in the routes of travel, and plans for diverting
smoke from escapeways. Traveling an escapeway in a completely enclosed
mantrip, such that the route could not be observed, would not meet the
requirement. As to the concept of exempting drills in the alternate
escapeway where mechanized transportation is unavailable if a
directional lifeline exists, MSHA believes that certain minimum
specifications for lifelines would be needed before such a compliance
alternative could be considered. This would expand the scope of this
rulemaking beyond the proposal.
One commenter suggested an expansion of 75.383 to require:
directional life lines in both escapeways; communications in both
escapeways; numbering of all stoppings along escapeways; additional
SCSR caches; hard hat stickers depicting escapeways and SCSR donning
procedures; and other measures. While many of the suggestions may have
merit, they are outside the scope of this rulemaking.
In the proposal, MSHA solicited comments on a concept to allow
individual miners to opt out of escapeway drills for health reasons.
One commenter indicated that a number of additional requirements would
be needed to assure that any miners opting out would still remain
familiar with the escapeways. After considering the comments received,
MSHA has not included an option for miners to opt out of the escapeway
drills. As one commenter pointed out, it is essential that each miner
be familiar with the escapeways. MSHA concludes that a number of
accommodations can be made to provide assistance to any miner
experiencing difficulty during drills. As discussed above, mobile
equipment may be used provided that the conveyance is not so enclosed
that miners cannot observe the route. Operators can allow additional
time for miners who may encounter difficulty. Also, assistance can be
provided by other miners, particularly in difficult areas such as
unusually steep grades. Such assistance would likely also be needed in
an actual emergency and therefore the drills would be particularly
instructive to all the miners participating in the drills.
MSHA believes that for areas where mechanized mining equipment is
being installed or removed, providing escapeways and posting maps
identifying these escapeways and conducting the drills specified in the
standard are essential to maintain safety. These requirements help to
assure that miners are familiar with escape routes so that should
urgent escape become necessary, they can reach the surface as quickly
as possible.
Section 75.384 Longwall and Shortwall Travelways
Modern mining methods include removing large blocks of coal in one
continuous operation along a wall which can be several hundred feet
long. This method is known as longwall or shortwall mining. To avoid
trapping miners in the face area without a means of escape in the event
of an emergency, there is a need to have a travelway on the side of the
block of coal opposite the escapeways. Section 75.384 addresses the
requirements for a travelway on the tailgate side of a longwall or
shortwall, the location and marking of the travelway, and procedures to
follow during a blockage of the travelway.
MSHA proposed no changes to the existing rule. Likewise, the final
rule makes no changes to the existing rule. The preamble to the
proposal explained that MSHA had received comment suggesting that the
existing rule be modified to provide for additional involvement by
miners when a roof fall or other blockage occurs that prevents travel
in the tailgate travelway. MSHA believes that the existing procedures
and regulations appropriately address the hazards and provide a
sufficient opportunity for input and involvement for all interested
parties. The preamble to the proposal contains a discussion of the
existing procedures and regulations.
One commenter recommended several additions to existing Sec. 75.384
while
[[Page 9822]]
agreeing that maintenance of a tailgate travelway is essential. The
recommendations included requiring the tailgate travelway to be
ventilated by intake air. The commenter noted that several mines
presently ventilate in this manner, providing intake air splits at both
headgate and tailgate. While this system has certain advantages, it is
not feasible or practical in all cases.
Section 75.388 Boreholes in Advance of Mining.
Areas of a mine, or of an adjacent mine, can be located in close
proximity to an advancing working place but can be inaccessible for a
variety of reasons. These inaccessible areas of a mine can present
hazards when mining proceeds inadvertently or improperly into these
areas. Inaccessible areas may contain potentially dangerous
accumulations of gases or water, which could result in explosions or
inundations. To protect against these hazards, Sec. 75.388 requires
operators to drill boreholes into the coal before they extract it. In
this manner, the operator can determine whether mining, if continued,
will penetrate an area where unknown hazards may be present. Boreholes
are not required when the area toward which mining is advancing is
accessible and is properly examined.
The final rule revises requirements for the drilling of boreholes
in advance of mining. It requires boreholes to be drilled in both ribs
of advancing working places unless an alternative drilling plan is
approved by the district manager in accordance with existing paragraph
(g) of this section. Existing paragraph (c) requires that boreholes be
drilled in at least one rib of advancing working places described in
Sec. 75.388 (a). Although MSHA did not intend any change in
promulgating the existing language, comments indicated that some
confusion existed. To address this issue, MSHA proposed to revise the
existing standard and adopt language similar to the regulation which
was in effect prior to 1992. The proposed revisions to Sec. 75.388 (c)
would have required bore holes to be drilled in one or both ribs of
advancing working places described in Sec. 75.388(a), `` . . . as may
be necessary for adequate protection of miners in such working
places.''
Several comments were received in response to the proposal. One
commenter indicated that the proposed revision was unnecessary since
the 1992 standard adequately indicated that more than one rib may need
to be drilled. Another commenter stated that drilling one rib is always
adequate since required drilling in adjacent places will assure that
the entire area is explored by drilling. MSHA's experience is that
working places are seldom developed at the same rate and some may lag
by significant distances. In addition, entry or room centers are
ordinarily in excess of the 20 foot drill hole depth specified in the
standard. Thus, coverage over the entire width of the advancing section
is not always provided as suggested by the commenter. Another example
would be where an advance heading approaches an inaccurately mapped
abandoned mine such that the unknown workings are approached near the
undrilled ribline. An inundation could occur at the undrilled ribline
as the working place advanced. To address these hazards, the final rule
requires drilling of both ribs. If the workings were not discovered
through drilling, multiple fatalities could result from inundations of
water, methane, or oxygen deficient atmosphere (black damp). Accidents
similar to this scenario have occurred and resulted in inundations of
water, methane, or irrespirable atmospheres.
One commenter noted that 38 inundations of gases or water occurred
between 1990 and 1994. MSHA notes that this number represents only
those accidental cut-throughs which resulted in inundations. It should
be noted that numerous additional accidental cut-throughs have occurred
which did not result in inundations. Each of these additional
accidental cut-throughs demonstrates the potential for a serious or
fatal accident. The commenter stated that the number of inundations and
the potential for multiple fatalities warrant a revision to the
standard to require both ribs to be drilled. Similar comments and
examples were heard during the public hearings. MSHA agrees.
MSHA concludes that in general, both ribs should be drilled;
however, under some circumstances drilling of both ribs may be
unnecessary. Moreover, MSHA recognizes that there are circumstances
where it would be unnecessary to drill both ribs at all times. Thus,
the final rule requires that both ribs be drilled unless the district
manager grants approval for an alternative drilling pattern under
existing paragraph (g). Under existing paragraph (g), an alternative
drilling pattern may be approved which may not require drilling of both
ribs. As with other plans which are subject to approval, requests for
alternative drilling patterns will be reviewed on a case by case basis.
After considering all comments received discussing this issue, MSHA has
concluded that the hazard of an inundation is properly addressed by the
final rule which retains sufficient flexibility for a site specific
drilling pattern if the district manager can be satisfied that the
alternative is suitable to the particular circumstances.
Another comment suggested that the minimum distances which trigger
drilling as specified in Sec. 75.388 (a)(1), (a)(2), and (a)(3) be
revised to 100, 500, and 500 feet, respectively. In support of the
suggestion, the commenter noted factors such as inaccurate old mine
maps, unmapped mining over-boundary or outside the legal limits, lost
maps or unknown mines, and less than diligent research by some
operators. The minimum drilling distances in paragraph (a) were not
proposed for revision and the final rule does not address them.
However, it is important to note that the distances specified are the
minimum at which drilling must begin if there is reasonable confidence
in the position of the old workings. The distances specified provide a
safety factor to account for slight mining overruns, mapping errors,
small deliberate omissions, and similar factors in cases where the
position of the old workings are known with reasonable certainty. In
cases where old workings are known to exist but the position is unknown
or known with little confidence, drilling would be necessary in excess
of the minimum distances specified in (a) to assure compliance with the
standard.
Section 75.389 Mining into Inaccessible Areas
While Sec. 75.388 addresses the need to identify inaccessible areas
to avoid accidentally drilling into an area containing a possible
hazardous environment, Sec. 75.389 establishes procedures for drilling
into an inaccessible area that has been identified. Section 75.389
requires a separate plan be developed and approved for drilling into
inaccessible areas. Paragraph (c) of the final rule clarifies that the
requirements of Sec. 75.389(c)(1), (c)(2) and (c)(3) do not apply to
routine mining-through operations that are part of a retreat section
ventilation system approved in accordance with Sec. 75.371(f) and (x).
The final rule retains the proposed language.
The preamble to the proposal pointed out that, based on comments
received during informational meetings and other discussions, differing
interpretations of the application of existing Sec. 75.389 existed.
Some persons were interpreting paragraph (c) as requiring, for example,
the mine to be evacuated during the break-through of a pillar split in
a retreating section. However, paragraphs (a) through (c) of
Sec. 75.389 were intended to apply during mining-through operations in
areas subject to Sec. 75.388
[[Page 9823]]
where hazards and potential hazards may be unknown. The final rule
revises existing Sec. 75.389(c) by adding an exception for routine
mining-through operations that are a part of a retreat mining system
approved in the mine ventilation plan. In some circumstances, the
mining through occurs during routine mining into an area which is
covered by an approved mine ventilation plan. In this case, the
potential hazards have already been addressed in the mine ventilation
plan. Requiring the operator to submit duplicate plans would not result
in any safety benefit; therefore, the level of safety provided by the
existing standard is maintained.
Petitions for Modification
Operators with petitions for modification that involve the
standards revised in this rulemaking need to determine the status of
those petitions before the effective date of the rule. If there are
sections of this rule that are renumbered but remain substantively
unchanged from the existing standards, operators with modifications
granted for these standards need not reapply. However, operators with
petitions for modifications granted for standards that have been
revised must comply with the new rule on its effective date. New
petitions for modification of the final rule may be submitted under 30
CFR part 44. If Agency assistance is needed, questions should be
directed to the appropriate MSHA district office.
Derivation Table
The following derivation table lists the number of each final
standard and the number of the existing standard from which it is
derived.
------------------------------------------------------------------------
New section Old section
------------------------------------------------------------------------
75.301....................... Partly new, 75.301.
75.310(a)(3)................. Partly new, 75.310(a)(3).
75.310(a)(4)................. Partly new, 75.310(a)(4).
75.310(c).................... Partly new, 75.310(c).
75.310(c)(1)................. Partly new, 75.310(c).
75.310(c)(2)................. 75.310(c).
75.310(c)(3)................. New.
75.310(c)(4)................. Partly new, 75.310(c).
75.310(c)(4)(i).............. 75.310(c)(1).
75.310(c)(4)(ii)............. 75.310(c)(2).
75.310(c)(5)................. New.
75.311(d).................... Partly new, 75.311(d).
75.312(a).................... Partly new, 75.312(a).
75.312(b)(1)................. Partly new, 75.312(b)(1).
75.312(b)(1)(i).............. New.
75.312(b)(1)(ii)............. 75.312(b)(1) through(b)(1)(ii).
75.312(c).................... Partly new, 75.312(c).
75.312(d).................... Partly new, 75.312(d).
75.312(f)(1)................. 75.312(f).
75.312(f)(2)................. New.
75.312(g)(1)................. Partly new, 75.312(g)(1).
75.312(g)(2)................. New.
75.312(g)(3)................. Partly new, 75.312(g)(3).
75.312(h).................... Partly new, 75.312(h).
75.313(a)(1)................. 75.313(a)(1).
75.313(a)(2)................. 75.313(a)(2).
75.313(a)(3)................. 75.313(a)(3).
75.313(b).................... 75.313(b).
75.313(c)(1)................. 75.313(c)(1).
75.313(c)(2)................. Partly new, 75.313(c)(2).
75.313(c)(3)................. Partly new, 75.313(c)(3).
75.313(d)(1)(i).............. Partly new, 75.313(d)(1)(i).
75.313(d)(1)(ii)............. Partly new, 75.313(d)(1)(ii).
75.313(d)(2)................. Partly new, 75.313(d)(2).
75.320(e).................... New.
75.321(a)(1)................. Partly new, 75.321(a).
75.321(a)(2)................. Partly new, 75.321(a).
75.323(b)(1)................. 75.323(b)(1).
75.323(b)(1)(i).............. 75.323(b)(1)(i).
75.323(b)(1)(ii)............. Partly new, 75.323(b)(1)(ii).
75.323(b)(1)(iii)............ 75.323(b)(1)(iii).
75.323(b)(2)................. 75.323(b)(2).
75.323(b)(2)(i).............. 75.323(b)(2)(i).
75.323(b)(2)(ii)............. 75.323(b)(2)(ii).
75.323(c)(1)................. Partly new, 75.323(c)(1).
75.323(d)(2)(i).............. Partly new, 75.323(d)(2)(i).
75.325(d).................... Partly new, 75.325(d).
75.330(c).................... New.
75.332(a)(1)................. 75.332(a)(1).
75.333(a).................... Partly new, 75.333(a).
75.333(b)(1)................. Partly new, 75.333(b)(1).
75.333(b)(3)................. Partly new, 75.333(b)(3).
75.333(b)(4)................. Partly new, 75.333(b)(4).
75.333(e)(1)(i).............. Partly new, 75.333(e)(1).
75.333(e)(1)(ii)............. Partly new, 75.333(e)(2).
75.333(h).................... 75.333(e)(1).
75.334(e).................... Partly new, 75.334(e).
[[Page 9824]]
75.334(f)(3)................. Partly new, 75.334(f)(3).
75.340(a).................... Partly new, 75.340(a).
75.342(a)(4)................. Partly new, 75.342(a)(4).
75.342(a)(4)(i).............. New.
75.342(a)(4)(ii)............. New.
75.342(a)(4)(iii)............ New.
75.344(a).................... Partly new, 75.344(a).
75.344(a)(1)................. Partly new, 75.344(b)(1).
75.344(a)(2)................. Partly new, 75.344(a)(1).
75.344(a)(2)(i).............. 75.344(b)(2)(i).
75.344(a)(2)(ii)............. 75.344(b)(2)(ii).
75.344(b).................... Partly new, 75.344(a)(2).
75.344(e).................... New.
75.360(a)(1)................. Partly new, 75.360(a)(1).
75.360(a)(2)................. New.
75.360(b).................... 75.360(b).
75.360(b)(1)................. Partly new, 75.360(b)(1).
75.360(b)(3)................. Partly new, 75.360(b)(3).
75.360(b)(4)................. Partly new, 75.360(b)(4).
75.360(b)(6)(i).............. Partly new, 75.360(b)(6).
75.360(b)(6)(ii)............. Partly new, 75.360(b)(6).
75.360(b)(8)................. New.
75.360(b)(9)................. New.
75.360(b)(10)................ New.
75.360(e).................... 75.360(f).
75.360(f).................... Partly new, 75.360(g).
75.360(g).................... Partly new, 75.360(h).
75.362(a)(1)................. Partly new, 75.362(a)(1).
75.362(a)(2)................. New.
75.362(c)(1)................. Partly new, 75.362(c)(1).
75.362(c)(2)................. 75.362(c)(2).
75.362(d)(1)(i).............. New.
75.362(d)(1)(iii)............ Partly new, 75.362(d)(1)(ii).
75.362(d)(2)................. Partly new, 75.362(d)(2).
75.362(g)(1)................. New.
75.362(g)(2)................. New.
75.363....................... Partly new, 75.313, 75.361, 75.362.
75.364(a)(1)................. Partly new, 75.364(a)(1).
75.364(a)(2)(i).............. Partly new, 75.364(a)(2)(i).
75.364(a)(2)(ii)............. Partly new, 75.364(a)(2)(ii).
75.364(a)(2)(iii)............ Partly new, 75.364(a)(2)(iii).
75.364(a)(2)(iv)............. Partly new, 75.364(a)(2)(iii).
75.364(h).................... Partly new, 75.364(h).
75.364(i).................... Partly new, 75.364(i).
75.370(a)(3)................. Partly new, 75.370(a)(3).
75.370(a)(3)(i).............. New.
75.370(a)(3)(ii)............. 75.370(a)(3).
75.370(a)(3)(iii)............ Partly new, 75.370(a)(3).
75.370(b).................... New.
75.370(c)(1)................. Partly new, 75.370(b)(1).
75.370(c)(2)................. 75.370(b)(2).
75.370(f).................... Partly new, 75.370(e).
75.370(f)(1)................. New.
75.370(f)(2)................. Partly new, 75.370(e).
75.370(f)(3)................. Partly new, 75.370(e).
75.371(r).................... Partly new, 75.371(r).
75.371(s).................... Partly new, 75.371(s).
75.371(z).................... Partly new, 75.371(z).
75.371(bb)................... Partly new, 75.371(bb).
75.371(cc)................... Partly new, 75.371(cc).
75.372(b)(3)................. Partly new, 75.372(b)(3).
75.372(b)(19)................ New.
75.372(b)(20)................ New.
75.380(b)(1)................. 75.380(b)(1).
75.380(b)(2)................. 75.380(b)(2).
75.380(d)(3)................. Partly new, 75.380(d)(3).
75.380(d)(4)(ii)............. Partly new, 75.380(d)(4)(ii).
75.380(d)(4)(iii)............ New.
75.380(d)(4)(iv)............. New.
75.380(d)(5)................. Partly new, 75.380(d)(5).
75.380(f).................... Partly new, 75.380(f)(1).
75.380(f)(1)................. Partly new, 75.380(f)(1).
75.380(f)(2)................. Partly new, 75.380(f)(1).
[[Page 9825]]
75.380(f)(3)................. Partly new, 75.380(f)(1).
75.380(f)(4)................. Partly new, 75.380(f)(2).
75.380(f)(5)................. Partly new, 75.380(f)(2).
75.380(f)(6)................. New.
75.380(f)(7)................. New.
75.380(i)(2)................. Partly new, 75.380(i)(2).
75.382(g).................... New.
75.383(a).................... Partly new, 75.383(a).
75.383(b)(1)................. 75.383(b)(1).
75.388(c).................... Partly new, 75.388(c).
75.389(c).................... New.
75.389(c)(1)................. 75.389(c)(1).
------------------------------------------------------------------------
Redesignation Table
The following redesignation table lists the section number of the
existing standard and the section number of the final standard which
contain revised provisions derived from the corresponding existing
section.
----------------------------------------------------------------------------------------------------------------
Old section New section
----------------------------------------------------------------------------------------------------------------
75.310(a)(3).................................... 75.310(a)(3).
75.310(a)(4).................................... 75.310(a)(4).
75.310(c)....................................... 75.310(c).
75.310(c)....................................... 75.310(c)(1).
75.310(c)....................................... 75.310(c)(2).
75.310(c)....................................... 75.310(c)(4).
75.310(c)(1).................................... 75.310(c)(4)(i).
75.310(c)(2).................................... 75.310(c)(4)(ii).
75.311(d)....................................... 75.311(d).
75.312(a)....................................... 75.312(a).
75.312(b)(1).................................... 75.312(b)(1), 75.312(b)(1)(ii).
75.312(b)(1)(i)................................. 75.312(b)(1)(ii)(A).
75.312(b)(1)(ii)................................ 75.312(b)(1)(ii)(B).
75.312(c)....................................... 75.312(c).
75.312(d)....................................... 75.312(d).
75.312(f)....................................... 75.312(f)(1).
75.312(g)(1).................................... 75.312(g)(1).
75.312(g)(3).................................... 75.312(g)(3).
75.312(h)....................................... 75.312(h).
75.313(c)(2).................................... 75.313(c)(2).
75.313(c)(3).................................... 75.313(c)(3).
75.313(d)(1)(i)................................. 75.313(d)(1)(i).
75.313(d)(1)(ii)................................ 75.313(d)(1)(ii).
75.321(a)....................................... 75.321(a)(1).
75.321(a)....................................... 75.321(a)(2).
75.323(b)(1)(ii)................................ 75.323(b)(1)(ii).
75.323(c)(1).................................... 75.323(c)(1).
75.323(d)(2)(i)................................. 75.323(d)(2)(i).
75.325(d)....................................... 75.325(d).
75.333(a)....................................... 75.333(a).
75.333(b)(1).................................... 75.333(b)(1).
75.333(b)(3).................................... 75.333(b)(3).
75.333(b)(4).................................... 75.333(b)(4).
75.333(e)(1).................................... 75.333(e)(1)(i).
75.333(e)(1).................................... 75.333(e)(1)(ii).
75.334(e)....................................... 75.334(e).
75.334(f)(3).................................... 75.334(f)(3).
75.340(a)....................................... 75.340(a)
75.340(a)(1).................................... 75.340(a)(1)(i).
75.340(a)(2).................................... 75.340(a)(1)(ii).
75.340(a)(3).................................... 75.340(a)(1)(iii).
75.340(a)(3)(i)................................. 75.340(a)(1)(iii)(A).
75.340(a)(3)(ii)................................ 75.340(a)(1)(iii)(B).
75.340(a)....................................... 75.340(a)(2).
75.340(a)(1).................................... 75.340(a)(2)(i).
75.340(a)(2).................................... 75.340(a)(2)(ii).
75.342(a)(4).................................... 75.342(a)(4).
75.344(a)....................................... 75.344(a).
75.344(a)(1).................................... 75.344(a)(2).
75.344(a)(2).................................... 75.344(b).
75.344(b)(1).................................... 75.344(a)(1).
75.344(b)(2).................................... 75.344(a)(2).
75.344(b)(2)(i)................................. 75.344(a)(2)(i).
[[Page 9826]]
75.344(b)(2)(ii)................................ 75.344(a)(2)(ii).
75.360(a)....................................... 75.360(a)(1).
75.360(b)....................................... 75.360(b).
75.360(b)(1).................................... 75.360(b)(1).
75.360(b)(3).................................... 75.360(b)(3).
75.360(b)(4).................................... 75.350(b)(4).
75.360(b)(6).................................... 75.360(b)(6)(i).
75.360(b)(6).................................... 75.360(b)(6)(ii).
75.360(c)....................................... 75.360(c).
75.360(c)(1).................................... 75.360(c)(1).
75.360(c)(3..................................... 75.360(c)(3).
75.360(e)....................................... 75.363.
75.360(f)....................................... 75.360(e).
75.360(g)....................................... 75.360(f).
75.360(h)....................................... 75.360(g).
75.362(a)(1).................................... 75.362(a)(1).
75.363(a)(2).................................... 75.363.
75.362(c)(1).................................... 75.362(c)(1).
75.362(d)(1)(i)................................. 75.362(d)(1)(ii).
75.362(d)(1)(ii)................................ 75.362(d)(1)(iii).
75.362(d)(2).................................... 75.362(d)(2).
75.362(g)....................................... 75.363.
75.362(h)....................................... 75.363.
75.364(a)(1).................................... 75.364(a)(1).
75.364(a)(2)(i)................................. 75.364(a)(2)(i).
75.364(a)(2)(ii)................................ 75.364(a)(2)(ii).
75.364(a)(2)(iii)............................... 75.364(a)(2)(iii).
75.364(h)....................................... 75.364(h).
75.364(i)....................................... 75.364(i).
75.370(a)(3).................................... 75.370(a)(3).
75.370(a)(3).................................... 75.370(a)(3)(ii).
75.370(a)(3).................................... 75.370(a)(3)(iii).
75.370(b)(1).................................... 75.370(c)(1).
75.370(b)(2).................................... 75.370(c)(2).
75.370(e)....................................... 75.370(f).
75.370(e)....................................... 75.370(f)(2).
75.370(e)....................................... 75.370(f)(3).
75.371(r)....................................... 75.371(r).
75.371(s)....................................... 75.371(s).
75.371(z)....................................... 75.371(z).
75.371(bb)...................................... 75.371(bb).
75.371(cc)...................................... 75.371(cc).
75.372(b)(3).................................... 75.372(b)(3).
75.380(d)(3).................................... 75.380(d)(3).
75.380(d)(4)(ii)................................ 75.380(d)(4)(ii).
75.380(d)(5).................................... 75.380(d)(5).
75.380(f)....................................... 75.380(f).
75.380(i)(2).................................... 75.380(i)(2).
75.383(a)....................................... 75.383(a).
75.388(c)....................................... 75.388(c).
75.389(c)(1).................................... 75.389(c)(1).
----------------------------------------------------------------------------------------------------------------
III. Paperwork Reduction Act
The information collection requirements contained in this rule have
been submitted to the Office of Management and Budget (OMB) for review
under the Paperwork Reduction Act of 1995 (44 U.S.C. 3501-3520), as
implemented by OMB in regulations at 5 CFR part 1320. No person may be
required to respond to, or may be subjected to a penalty for failure to
comply with, these information collection requirements until they have
been approved and MSHA has announced the assigned OMB control number.
The OMB control number, when assigned, will be announced by separate
notice in the Federal Register. In accordance with Sec. 1320.11(h) of
the implementing regulations, OMB has 60 days from today's publication
date in which to approve, disapprove, or instruct MSHA to make a change
to the information collection requirements in this rule.
This final rule addresses comments submitted to OMB and MSHA on the
collection of information requirements in the proposed rule. In
revising the requirements from those that appeared in the proposed
rule, MSHA has evaluated the necessity and usefulness of the
collections of information; reevaluated MSHA's estimate of the
information collection burden, including the validity of the underlying
methodology and assumptions; and minimized the burden on respondents
for the information collection requirements, to the extent possible.
This final rule provides for the use of electronic storage and
maintenance of records.
Benefits
In assessing costs and benefits of the ventilation rule, it is
important to note that ventilation of underground coal mines is the
primary method of preventing the accumulation of explosive methane gas,
controlling harmful respirable dust, and assuring the quality of air
miners breath. Because
[[Page 9827]]
of the potential for a large number of fatalities resulting from
ventilation problems, MSHA has found it prudent to establish multiple
safety factors and safety work practices to better assure adequate
protection for miners. It is extremely difficult to specifically
quantify safety benefits related to each safety factor. However, due to
the close, confined nature of the workplace in an underground coal
mine, failure of any safety factors or protective actions related to
ventilation can have disastrous effects. The introduction of this rule
lists some of those tragic mine accidents. In the restricted work
environment of an underground coal mine, failure of a single safety
factor or noncompliance with a safe work practice could jeopardize the
well-being of all miners underground. The total effect of the
provisions in this final rule in conjunction with MSHA's existing
ventilation standards should decrease the occurrence of fatalities,
injuries, accidents, and illnesses in underground coal mines.
With respect to this final rule, the Agency has identified nine
fatalities and seven injuries which potentially could have been
prevented by compliance with these provisions. In addition, the final
rule contains provisions to better assure compliance with the
respirable dust control parameters specified in the mine ventilation
plan. Adherence to these parameters helps to maintain a work
environment free of excessive levels of respirable dust, thereby
improving long-term health protection for miners and potentially
reducing the number of miners afflicted with coal workers'
pneumoconiosis.
Some provisions clarify the intent of the existing rule. Such
clarifications should increase the likelihood of compliance and thereby
will help to increase the probability of preventing a fatality, injury,
or non-injury accident. For the provisions which offer an alternative
compliance option, the miners will be provided at least the same level
of safety provided by an existing requirement. These provisions will
facilitate compliance by the operator, thereby increasing the potential
for the rule to reduce the probability of a ventilation-related
explosion or accident.
In conclusion, the Agency determined that these provisions will
increase the probability that compliance with the ventilation rule will
prevent future ventilation-related accidents and generate a safer
mining environment.
Compliance Costs and Economic Impact
MSHA has compared the costs associated with the existing
requirements with the costs of the new requirements. Based upon the
available data, MSHA estimates that compliance with the rule will
produce net total per year costs of approximately $4.0 million for the
mining industry. This $4.0 million is composed of approximately $0.6
million in net annualized costs (derived from $4.0 million one-time
costs) and approximately $3.4 million net annual recurring costs.
With respect to large underground coal mines the net total per year
costs will be approximately $3.0 million. This $3.0 million is composed
of approximately $0.46 million in net annualized costs (derived from
$3.0 million one-time costs) and approximately $2.54 million net annual
recurring costs.
With respect to small underground coal mines the net total per year
costs will be approximately $1.0 million. This $1.0 million is composed
of approximately $0.14 million in net annualized costs (derived from
$1.0 million one-time costs) and approximately $0.82 million net annual
recurring costs.
Executive Order 12866 requires that regulatory agencies assess the
impact to the government for any regulation determined to be a
significant regulatory action. MSHA does not believe that this rule
will create any significant cost impacts to the government. The
regulation can be implemented under existing government practices
without any substantial equipment or facility expenditures by the
government.
The incremental compliance costs for all underground coal mines are
listed by provision in Table I.
Table IV-1.--Compliance Costs to Comply With the Ventilation Rule for
all Underground Coal Mines
[In thousands of dollars]
------------------------------------------------------------------------
First
Standard year Annualized Annual
costs costs costs
------------------------------------------------------------------------
75.301.................................. (100) (7) (20)
75.310.................................. 329 47 (70)
75.311.................................. ....... .......... .........
75.312.................................. ....... .......... (1,121)
75.313.................................. ....... .......... 322
75.320.................................. ....... .......... .........
75.321.................................. 250 35 40
75.323.................................. ....... .......... .........
75.330.................................. ....... .......... .........
75.333.................................. ....... .......... .........
75.334.................................. ....... .......... .........
75.340.................................. 63 9
75.342.................................. 12 2 38
75.344.................................. 57 10 1,256
75.360.................................. 123 17 (1,556)
75.362.................................. 420 59 3,275
75.363.................................. ....... .......... 321
75.364.................................. ....... .......... 682
75.370.................................. ....... .......... 67
75.371.................................. ....... .......... 13
75.372.................................. ....... .......... .........
75.380.................................. 2,839 436 51
75.382.................................. ....... .......... 13
75.388.................................. ....... .......... 53
[[Page 9828]]
75.389..................................
-------------------------------
Total costs....................... 3,993 608 3,364
------------------------------------------------------------------------
Regulatory Flexibility Certification
The Regulatory Flexibility Act requires that agencies evaluate and
include, wherever possible, compliance alternatives that minimize any
adverse impact on small businesses when developing regulatory
standards. MSHA has not exempted small mines from any provision of the
rule and small mines will benefit from some of the provisions and the
alternative compliance methods.
MSHA determined that these revisions will not generate a
substantial cost increase for small mines. The lack of a substantial
cost increase for small mines, in conjunction with the fact that
similar hazards exist in both large and small mining operations,
indicates that regulatory relief is not warranted for small mining
operations. Therefore, MSHA has determined that these provisions will
not have a significantly adverse impact upon a substantial number of
small entities.
The incremental costs for small and large mines are listed by
provision in Table II.
Table IV-2.--Compliance Costs to Comply With the Ventilation Rule for Small and Large Underground Coal Mines
[In thousands of dollars]
----------------------------------------------------------------------------------------------------------------
First year costs Annualized costs Annual costs
Standard -----------------------------------------------------------------------------
Small Large Small Large Small Large
----------------------------------------------------------------------------------------------------------------
75.301............................ (100) (7) (20)
75.310............................ 273 56 39 8 (78) 8
75.311............................
75.312............................ (1,121)
75.313............................ 55 267
75.320............................
75.321............................ 250 35 40
75.323............................
75.330............................
75.333............................
75.334............................
75.340............................ 4 59 1 8
75.342............................ 6 6 1 1 18 20
75.344............................ 57 10 43 1,213
75.360............................ 37 86 5 12 100 (1,656)
75.362............................ 80 340 11 48 409 2,866
75.363............................ 98 223
75.364............................ 126 556
75.370............................ 12 55
75.371............................ 6 7
75.372............................
75.380............................ 585 2,254 89 347 6 45
75.382............................ 13
75.388............................ 25 28
75.389............................
-----------------------------------------------------------------------------
Total....................... 985 3,008 146 462 820 2,544
----------------------------------------------------------------------------------------------------------------
List of Subjects in 30 CFR Part 75
Escapeways, Mine safety and health, Underground coal mines,
Ventilation.
Dated: March 4, 1996.
J. Davitt McAteer,
Assistant Secretary for Mine Safety and Health.
Accordingly, part 75, subchapter O, chapter I, title 30 of the Code
of Federal Regulations is amended as follows:
PART 75--MANDATORY SAFETY STANDARDS--UNDERGROUND COAL MINES
1. The authority citation for part 75 is revised to read as
follows:
Authority: 30 U.S.C. 811.
2. Subpart D of part 75 is revised to read as follows:
[[Page 9829]]
Subpart D--Ventilation
Sec.
75.300 Scope.
75.301 Definitions.
75.302 Main mine fans.
75.310 Installation of main mine fans.
75.311 Main mine fan operation.
75.312 Main mine fan examinations and records.
75.313 Main mine fan stoppage with persons underground.
75.320 Air quality detectors and measurement devices.
75.321 Air quality.
75.322 Harmful quantities of noxious gases.
75.323 Actions for excessive methane.
75.324 Intentional changes in the ventilation system.
75.325 Air quantity.
75.326 Mean entry air velocity.
75.327 Air courses and trolley haulage systems.
75.330 Face ventilation control devices.
75.331 Auxiliary fans and tubing.
75.332 Working sections and working places.
75.333 Ventilation controls.
75.334 Worked-out areas and areas where pillars are being
recovered.
75.335 Construction of seals.
75.340 Underground electrical installations.
75.341 Direct-fired intake air heaters.
75.342 Methane monitors.
75.343 Underground shops.
75.344 Compressors.
75.350 Air courses and belt haulage entries.
75.351 Atmospheric monitoring system (AMS).
75.352 Return air courses.
75.360 Preshift examination.
75.361 Supplemental examination.
75.362 On-shift examination.
75.363 Hazardous conditions; posting, correcting and recording.
75.364 Weekly examination.
75.370 Mine ventilation plan; submission and approval.
75.371 Mine ventilation plan; contents.
75.372 Mine ventilation map.
75.373 Reopening mines.
75.380 Escapeways; bituminous and lignite mines.
75.381 Escapeways; anthracite mines.
75.382 Mechanical escape facilities.
75.383 Escapeway maps and drills.
75.384 Longwall and shortwall travelways.
75.385 Opening new mines.
75.386 Final mining of pillars.
75.388 Boreholes in advance of mining.
75.389 Mining into inaccessible areas.
Sec. 75.300 Scope.
This subpart sets requirements for underground coal mine
ventilation.
Sec. 75.301 Definitions.
In addition to the applicable definitions in Sec. 75.2, the
following definitions apply in this subpart.
Air course. An entry or a set of entries separated from other
entries by stoppings, overcasts, other ventilation control devices, or
by solid blocks of coal or rock so that any mixing of air currents
between each is limited to leakage.
Incombustible. Incapable of being burned.
Intake air. Air that has not yet ventilated the last working place
on any split of any working section, or any worked-out area, whether
pillared or nonpillared.
Intrinsically safe. Incapable of releasing enough electrical or
thermal energy under normal or abnormal conditions to cause ignition of
a flammable mixture of methane or natural gas and air of the most
easily ignitable composition.
Noncombustible Structure or Area. Describes a structure or area
that will continue to provide protection against flame spread for at
least 1 hour when subjected to a fire test incorporating an ASTM E119-
88 time/temperature heat input, or equivalent.
Noncombustible Material. Describes a material which when used to
construct a ventilation control results in a control that will continue
to serve its intended function for 1 hour when subjected to a fire test
incorporating an ASTM E119-88 time/temperature heat input, or
equivalent.
Return air. Air that has ventilated the last working place on any
split of any working section or any worked-out area whether pillared or
nonpillared. If air mixes with air that has ventilated the last working
place on any split of any working section or any worked-out area,
whether pillared or nonpillared, it is considered return air. For the
purposes of Sec. 75.507-1, air that has been used to ventilate any
working place in a coal producing section or pillared area, or air that
has been used to ventilate any working face if such air is directed
away from the immediate return is return air. Notwithstanding the
definition of intake air, for the purpose of ventilation of structures,
areas or installations that are required by this subpart D to be
ventilated to return air courses, and for ventilation of seals, other
air courses may be designated as return air courses by the operator
only when the air in these air courses will not be used to ventilate
working places or other locations, structures, installations or areas
required to be ventilated with intake air.
Worked-out area. An area where mining has been completed, whether
pillared or nonpillared, excluding developing entries, return air
courses, and intake air courses.
Sec. 75.302 Main mine fans.
Each coal mine shall be ventilated by one or more main mine fans.
Booster fans shall not be installed underground to assist main mine
fans except in anthracite mines. In anthracite mines, booster fans
installed in the main air current or a split of the main air current
may be used provided their use is approved in the ventilation plan.
Sec. 75.310 Installation of main mine fans.
(a) Each main mine fan shall be--
(1) Installed on the surface in an incombustible housing;
(2) Connected to the mine opening with incombustible air ducts;
(3) Equipped with an automatic device that gives a signal at the
mine when the fan either slows or stops. A responsible person
designated by the operator shall always be at a surface location at the
mine where the signal can be seen or heard while anyone is underground.
This person shall be provided with two-way communication with the
working sections and work stations where persons are routinely assigned
to work for the majority of a shift;
(4) Equipped with a pressure recording device or system. Mines
permitted to shut down main mine fans under Sec. 75.311 and which do
not have a pressure recording device installed on main mine fans shall
have until March 11, 1997 to install a pressure recording device or
system on all main mine fans. If a device or system other than a
circular pressure recorder is used to monitor main mine fan pressure,
the monitoring device or system shall provide a continuous graph or
continuous chart of the pressure as a function of time. At not more
than 7-day intervals, a hard copy of the continuous graph or chart
shall be generated or the record of the fan pressure shall be stored
electronically. When records of fan pressure are stored electronically,
the system used to store these records shall be secure and not
susceptible to alteration and shall be capable of storing the required
data. Records of the fan pressure shall be retained at a surface
location at the mine for at least 1 year and be made available for
inspection by authorized representatives of the Secretary and the
representative of miners;
(5) Protected by one or more weak walls or explosion doors, or a
combination of weak walls and explosion doors, located in direct line
with possible explosive forces;
(6) Except as provided under paragraph (e) of this section, offset
by at least 15 feet from the nearest side of the mine opening unless an
alternative method of protecting the fan and its associated components
is approved in the ventilation plan.
[[Page 9830]]
(b)(1) If an electric motor is used to drive a main mine fan, the
motor shall operate from a power circuit independent of all mine power
circuits.
(2) If an internal combustion engine is used to drive a main mine
fan--
(i) The fuel supply shall be protected against fires and
explosions;
(ii) The engine shall be installed in an incombustible housing and
be equipped with a remote shut-down device;
(iii) The engine and the engine exhaust system shall be located out
of direct line of the air current exhausting from the mine; and
(iv) The engine exhaust shall be vented to the atmosphere so that
the exhaust gases do not contaminate the mine intake air current or any
enclosure.
(c) If a main mine fan monitoring system is used under Sec. 75.312,
the system shall--
(1) Record, as described in paragraph (a)(4) the mine ventilating
pressure;
(2) Monitor bearing temperature, revolutions per minute, vibration,
electric voltage, and amperage;
(3) Provide a printout of the monitored parameters, including the
mine ventilating pressure within a reasonable period, not to exceed the
end of the next scheduled shift during which miners are underground;
and
(4) Be equipped with an automatic device that signals when--
(i) An electrical or mechanical deficiency exists in the monitoring
system; or
(ii) A sudden increase or loss in mine ventilating pressure occurs.
(5) Provide monitoring, records, printouts, and signals required by
paragraphs (c)(1) through (c)(4) at a surface location at the mine
where a responsible person designated by the operator is always on duty
and where signals from the monitoring system can be seen or heard while
anyone is underground. This person shall be provided with two-way
communication with the working sections and work stations where persons
are routinely assigned to work for the majority of a shift.
(d) Weak walls and explosion doors shall have cross-sectional areas
at least equal to that of the entry through which the pressure from an
explosion underground would be relieved. A weak wall and explosion door
combination shall have a total cross-sectional area at least equal to
that of the entry through which the pressure from an explosion
underground would be relieved.
(e) If a mine fan is installed in line with an entry, a slope, or a
shaft--
(1) The cross-sectional area of the pressure relief entry shall be
at least equal to that of the fan entry;
(2) The fan entry shall be developed out of direct line with
possible explosive forces;
(3) The coal or other solid material between the pressure relief
entry and the fan entry shall be at least 2,500 square feet; and
(4) The surface opening of the pressure relief entry shall be not
less than 15 feet nor more than 100 feet from the surface opening of
the fan entry and from the underground intersection of the fan entry
and pressure relief entry.
(f) In mines ventilated by multiple main mine fans, incombustible
doors shall be installed so that if any main mine fan stops and air
reversals through the fan are possible, the doors on the affected fan
automatically close.
Sec. 75.311 Main mine fan operation.
(a) Main mine fans shall be continuously operated, except as
otherwise approved in the ventilation plan, or when intentionally
stopped for testing of automatic closing doors and automatic fan signal
devices, maintenance or adjustment of the fan, or to perform
maintenance or repair work underground that cannot otherwise be made
while the fan is operating.
(b) Except as provided in paragraph (c) of this section, when a
main mine fan is intentionally stopped and the ventilating quantity
provided by the fan is not maintained by a back-up fan system--
(1) Only persons necessary to evaluate the effect of the fan
stoppage or restart, or to perform maintenance or repair work that
cannot otherwise be made while the fan is operating, shall be permitted
underground;
(2) Mechanized equipment shall be shut off before stopping the fan;
and
(3) Electric power circuits entering underground areas of the mine
shall be deenergized.
(c) When a back-up fan system is used that does not provide the
ventilating quantity provided by the main mine fan, persons may be
permitted in the mine and electric power circuits may be energized as
specified in the approved ventilation plan.
(d) If an unusual variance in the mine ventilation pressure is
observed, or if an electrical or mechanical deficiency of a main mine
fan is detected, the mine foreman or equivalent mine official, or in
the absence of the mine foreman or equivalent mine official, a
designated certified person acting for the mine foreman or equivalent
mine official shall be notified immediately, and appropriate action or
repairs shall be instituted promptly.
(e) While persons are underground, a responsible person designated
by the operator shall always be at a surface location where each main
mine fan signal can be seen or heard.
(f) The area within 100 feet of main mine fans and intake air
openings shall be kept free of combustible material, unless alternative
precautions necessary to provide protection from fire or other products
of combustion are approved in the ventilation plan.
(g) If multiple mine fans are used, the mine ventilation system
shall be designed and maintained to eliminate areas without air
movement.
(h) Any atmospheric monitoring system operated during fan stoppages
shall be intrinsically safe.
Sec. 75.312 Main mine fan examinations and records.
(a) To assure electrical and mechanical reliability of main mine
fans, each main mine fan and its associated components, including
devices for measuring or recording mine ventilation pressure, shall be
examined for proper operation by a trained person designated by the
operator. Examinations of main mine fans shall be made at least once
each day that the fan operates, unless a fan monitoring system is used.
No examination is required on any day when no one, including certified
persons, goes underground, except that an examination shall be
completed prior to anyone entering the mine.
(b)(1) If a main mine fan monitoring system is used, a trained
person designated by the operator shall--
(i) At least once each day review the data provided by the fan
monitoring system to assure that the fan and the fan monitoring system
are operating properly. No review is required on any day when no one,
including certified persons, goes underground, except that a review of
the data shall be performed prior to anyone entering the underground
portion of the mine. Data reviewed should include the fan pressure,
bearing temperature, revolutions per minute, vibration, electric
voltage, and amperage; and
(ii) At least every 7 days--
(A) Test the monitoring system for proper operation; and
(B) Examine each main mine fan and its associated components to
assure electrical and mechanical reliability of main mine fans.
(2) If the monitoring system malfunctions, the malfunction shall be
corrected, or paragraph (a) of this section shall apply.
(c) At least every 31 days, the automatic fan signal device for
each main mine fan shall be tested by stopping the fan. Only persons
[[Page 9831]]
necessary to evaluate the effect of the fan stoppage or restart, or to
perform maintenance or repair work that cannot otherwise be made while
the fan is operating, shall be permitted underground. Notwithstanding
the requirement of Sec. 75.311(b)(3), underground power may remain
energized during this test provided no one, including persons
identified in Sec. 75.311(b)(1), is underground. If the fan is not
restarted within 15 minutes, underground power shall be deenergized and
no one shall enter any underground area of the mine until the fan is
restarted and an examination of the mine is conducted as described in
Sec. 75.360 (b) through (e) and the mine has been determined to be
safe.
(d) At least every 31 days, the automatic closing doors in multiple
main mine fan systems shall be tested by stopping the fan. Only persons
necessary to evaluate the effect of the fan stoppage or restart, or to
perform maintenance or repair work that cannot otherwise be made while
the fan is operating, shall be permitted underground. Notwithstanding
the provisions of Sec. 75.311, underground power may remain energized
during this test provided no one, including persons identified in
Sec. 75.311(b)(1), is underground. If the fan is not restarted within
15 minutes, underground power shall be deenergized and no one shall
enter any underground area of the mine, until the fan is restarted and
an examination of the mine is conducted as described in Sec. 75.360 (b)
through (e) and the mine has been determined to be safe.
(e) Circular main mine fan pressure recording charts shall be
changed before the beginning of a second revolution.
(f)(1) Certification. Persons making main mine fan examinations
shall certify by initials and date at the fan or another location
specified by the operator that the examinations were made. Each
certification shall identify the main mine fan examined.
(2) Persons reviewing data produced by a main mine fan monitoring
system shall certify by initials and date on a printed copy of the data
from the system that the review was completed. In lieu of certification
on a copy of the data, the person reviewing the data may certify
electronically that the review was completed. Electronic certification
shall be by handwritten initials and date in a computer system so as to
be secure and not susceptible to alteration.
(g)(1) Recordkeeping. By the end of the shift on which the
examination is made, persons making main mine fan examinations shall
record all uncorrected defects that may affect the operation of the fan
that are not corrected by the end of that shift. Records shall be
maintained in a secure book that is not susceptible to alteration or
electronically in a computer system so as to be secure and not
susceptible to alteration.
(2) When a fan monitoring system is used in lieu of the daily fan
examination--
(i) The certified copies of data produced by fan monitoring systems
shall be maintained separate from other computer-generated reports or
data; and
(ii) A record shall be made of any fan monitoring system
malfunctions, electrical or mechanical deficiencies in the monitoring
system and any sudden increase or loss in mine ventilating pressure.
The record shall be made by the end of the shift on which the review of
the data is completed and shall be maintained in a secure book that is
not susceptible to alteration or electronically in a computer system so
as to be secure and not susceptible to alteration.
(3) By the end of the shift on which the monthly test of the
automatic fan signal device or the automatic closing doors is
completed, persons making these tests shall record the results of the
tests. Records shall be maintained in a secure book that is not
susceptible to alteration or electronically in a computer system so as
to be secure and not susceptible to alteration.
(h) Retention period. Records, including records of mine fan
pressure and the certified copies of data produced by fan monitoring
systems, shall be retained at a surface location at the mine for at
least 1 year and shall be made available for inspection by authorized
representatives of the Secretary and the representative of miners.
Sec. 75.313 Main mine fan stoppage with persons underground.
(a) If a main mine fan stops while anyone is underground and the
ventilating quantity provided by the fan is not maintained by a back-up
fan system--
(1) Electrically powered equipment in each working section shall be
deenergized;
(2) Other mechanized equipment in each working section shall be
shut off; and
(3) Everyone shall be withdrawn from the working sections and areas
where mechanized mining equipment is being installed or removed.
(b) If ventilation is restored within 15 minutes after a main mine
fan stops, certified persons shall examine for methane in the working
places and in other areas where methane is likely to accumulate before
work is resumed and before equipment is energized or restarted in these
areas.
(c) If ventilation is not restored within 15 minutes after a main
mine fan stops--
(1) Everyone shall be withdrawn from the mine;
(2) Underground electric power circuits shall be deenergized.
However, circuits necessary to withdraw persons from the mine need not
be deenergized if located in areas or haulageways where methane is not
likely to migrate to or accumulate. These circuits shall be deenergized
as persons are withdrawn; and
(3) Mechanized equipment not located on working sections shall be
shut off. However, mechanized equipment necessary to withdraw persons
from the mine need not be shut off if located in areas where methane is
not likely to migrate to or accumulate.
(d)(1) When ventilation is restored--
(i) No one other than designated certified examiners shall enter
any underground area of the mine until an examination is conducted as
described in Sec. 75.360(b) through (e) and the area has been
determined to be safe. Designated certified examiners shall enter the
underground area of the mine from which miners have been withdrawn only
after the fan has operated for at least 15 minutes unless a longer
period of time is specified in the approved ventilation plan.
(ii) Underground power circuits shall not be energized and
nonpermissible mechanized equipment shall not be started or operated in
an area until an examination is conducted as described in
Sec. 75.360(b) through (e) and the area has been determined to be safe,
except that designated certified examiners may use nonpermissible
transportation equipment in intake airways to facilitate the making of
the required examination.
(2) If ventilation is restored to the mine before miners reach the
surface, the miners may return to underground working areas only after
an examination of the areas is made by a certified person and the areas
are determined to be safe.
(e) Any atmospheric monitoring system operated during fan stoppages
shall be intrinsically safe.
Sec. 75.320 Air quality detectors and measurement devices.
(a) Tests for methane shall be made by a qualified person with MSHA
approved detectors that are maintained in permissible and proper
operating condition and calibrated with a known
[[Page 9832]]
methane-air mixture at least once every 31 days.
(b) Tests for oxygen deficiency shall be made by a qualified person
with MSHA approved oxygen detectors that are maintained in permissible
and proper operating condition and that can detect 19.5 percent oxygen
with an accuracy of 0.5 percent. The oxygen detectors shall
be calibrated at the start of each shift that the detectors will be
used.
(c) Handheld devices that contain electrical components and that
are used for measuring air velocity, carbon monoxide, oxides of
nitrogen, and other gases shall be approved and maintained in
permissible and proper operating condition.
(d) An oxygen detector approved by MSHA shall be used to make tests
for oxygen deficiency required by the regulations in this part.
Permissible flame safety lamps may only be used as a supplementary
testing device.
(e) Maintenance of instruments required by paragraphs (a) through
(d) of this section shall be done by persons trained in such
maintenance.
Sec. 75.321 Air quality.
(a)(1) The air in areas where persons work or travel, except as
specified in paragraph (a)(2) of this section, shall contain at least
19.5 percent oxygen and not more than 0.5 percent carbon dioxide, and
the volume and velocity of the air current in these areas shall be
sufficient to dilute, render harmless, and carry away flammable,
explosive, noxious, and harmful gases, dusts, smoke, and fumes.
(2) The air in areas of bleeder entries and worked-out areas where
persons work or travel shall contain at least 19.5 percent oxygen, and
carbon dioxide levels shall not exceed 0.5 percent time weighted
average and 3.0 percent short term exposure limit.
(b) Notwithstanding the provisions of Sec. 75.322, for the purpose
of preventing explosions from gases other than methane, the following
gases shall not be permitted to accumulate in excess of the
concentrations listed below:
(1) Carbon monoxide (CO)--2.5 percent
(2) Hydrogen (H2)--.80 percent
(3) Hydrogen sulfide (H2S)--.80 percent
(4) Acetylene (C2H2)--.40 percent
(5) Propane (C3H8)--.40 percent
(6) MAPP (methyl-acetylene-propylene-propodiene)--.30 percent
Sec. 75.322 Harmful quantities of noxious gases.
Concentrations of noxious or poisonous gases, other than carbon
dioxide, shall not exceed the current threshold limit values (TLV) as
specified and applied by the ACGIH. Detectors or laboratory analysis of
mine air samples shall be used to determine the concentrations of
harmful, noxious, or poisonous gases.
Sec. 75.323 Actions for excessive methane.
(a) Location of tests. Tests for methane concentrations under this
section shall be made at least 12 inches from the roof, face, ribs, and
floor.
(b) Working places and intake air courses.
(1) When 1.0 percent or more methane is present in a working place
or an intake air course, including an air course in which a belt
conveyor is located, or in an area where mechanized mining equipment is
being installed or removed--
(i) Except intrinsically safe atmospheric monitoring systems (AMS),
electrically powered equipment in the affected area shall be
deenergized, and other mechanized equipment shall be shut off;
(ii) Changes or adjustments shall be made at once to the
ventilation system to reduce the concentration of methane to less than
1.0 percent; and
(iii) No other work shall be permitted in the affected area until
the methane concentration is less than 1.0 percent.
(2) When 1.5 percent or more methane is present in a working place
or an intake air course, including an air course in which a belt
conveyor is located, or in an area where mechanized mining equipment is
being installed or removed--
(i) Everyone except those persons referred to in Sec. 104(c) of the
Act shall be withdrawn from the affected area; and
(ii) Except for intrinsically safe AMS, electrically powered
equipment in the affected area shall be disconnected at the power
source.
(c) Return air split. (1) When 1.0 percent or more methane is
present in a return air split between the last working place on a
working section and where that split of air meets another split of air,
or the location at which the split is used to ventilate seals or
worked-out areas changes or adjustments shall be made at once to the
ventilation system to reduce the concentration of methane in the return
air to less than 1.0 percent.
(2) When 1.5 percent or more methane is present in a return air
split between the last working place on a working section and where
that split of air meets another split of air, or the location where the
split is used to ventilate seals or worked-out areas--
(i) Everyone except those persons referred to in Sec. 104(c) of the
Act shall be withdrawn from the affected area;
(ii) Other than intrinsically safe AMS, equipment in the affected
area shall be deenergized, electric power shall be disconnected at the
power source, and other mechanized equipment shall be shut off; and
(iii) No other work shall be permitted in the affected area until
the methane concentration in the return air is less than 1.0 percent.
(d) Return air split alternative. (1) The provisions of this
paragraph apply if--
(i) The quantity of air in the split ventilating the active
workings is at least 27,000 cubic feet per minute in the last open
crosscut or the quantity specified in the approved ventilation plan,
whichever is greater;
(ii) The methane content of the air in the split is continuously
monitored during mining operations by an AMS that gives a visual and
audible signal on the working section when the methane in the return
air reaches 1.5 percent, and the methane content is monitored as
specified in Sec. 75.351; and
(iii) Rock dust is continuously applied with a mechanical duster to
the return air course during coal production at a location in the air
course immediately outby the most inby monitoring point.
(2) When 1.5 percent or more methane is present in a return air
split between a point in the return opposite the section loading point
and where that split of air meets another split of air or where the
split of air is used to ventilate seals or worked-out areas--
(i) Changes or adjustments shall be made at once to the ventilation
system to reduce the concentration of methane in the return air below
1.5 percent;
(ii) Everyone except those persons referred to in Sec. 104(c) of
the Act shall be withdrawn from the affected area;
(iii) Except for intrinsically safe AMS, equipment in the affected
area shall be deenergized, electric power shall be disconnected at the
power source, and other mechanized equipment shall be shut off; and
(iv) No other work shall be permitted in the affected area until
the methane concentration in the return air is less than 1.5 percent.
(e) Bleeders and other return air courses. The concentration of
methane in a bleeder split of air immediately before the air in the
split joins another split of air, or in a return air course other than
as described in paragraphs (c) and (d) of this section, shall not
exceed 2.0 percent.
[[Page 9833]]
Sec. 75.324 Intentional changes in the ventilation system.
(a) A person designated by the operator shall supervise any
intentional change in ventilation that--
(1) Alters the main air current or any split of the main air
current in a manner that could materially affect the safety or health
of persons in the mine; or
(2) Affects section ventilation by 9,000 cubic feet per minute of
air or more in bituminous or lignite mines, or 5,000 cubic feet per
minute of air or more in anthracite mines.
(b) Intentional changes shall be made only under the following
conditions:
(1) Electric power shall be removed from areas affected by the
ventilation change and mechanized equipment in those areas shall be
shut off before the ventilation change begins.
(2) Only persons making the change in ventilation shall be in the
mine.
(3) Electric power shall not be restored to the areas affected by
the ventilation change and mechanized equipment shall not be restarted
until a certified person has examined these areas for methane
accumulation and for oxygen deficiency and has determined that the
areas are safe.
Sec. 75.325 Air quantity.
(a)(1) In bituminous and lignite mines the quantity of air shall be
at least 3,000 cubic feet per minute reaching each working face where
coal is being cut, mined, drilled for blasting, or loaded. When a
greater quantity is necessary to dilute, render harmless, and carry
away flammable, explosive, noxious, and harmful gases, dusts, smoke,
and fumes, this quantity shall be specified in the approved ventilation
plan. A minimum air quantity may be required to be specified in the
approved ventilation plan for other working places or working faces.
(2) The quantity of air reaching the working face shall be
determined at or near the face end of the line curtain, ventilation
tubing, or other ventilation control device. If the curtain, tubing, or
device extends beyond the last row of permanent roof supports, the
quantity of air reaching the working face shall be determined behind
the line curtain or in the ventilation tubing at or near the last row
of permanent supports.
(3) If machine mounted dust collectors or diffuser fans are used,
the approved ventilation plan shall specify the operating volume of the
dust collector or diffuser fan.
(b) In bituminous and lignite mines, the quantity of air reaching
the last open crosscut of each set of entries or rooms on each working
section and the quantity of air reaching the intake end of a pillar
line shall be at least 9,000 cubic feet per minute unless a greater
quantity is required to be specified in the approved ventilation plan.
(c) In longwall and shortwall mining systems--
(1) The quantity of air shall be at least 30,000 cubic feet per
minute reaching the working face of each longwall, unless the operator
demonstrates that a lesser air quantity will maintain continual
compliance with applicable methane and respirable dust standards. This
lesser quantity shall be specified in the approved ventilation plan. A
quantity greater than 30,000 cubic feet per minute may be required to
be specified in the approved ventilation plan.
(2) The velocity of air that will be provided to control methane
and respirable dust below applicable standards on each longwall or
shortwall and the locations where these velocities will be provided
shall be specified in the approved ventilation plan. The locations
specified shall be at least 50 feet but no more than 100 feet from the
headgate and tailgate, respectively.
(d) Ventilation shall be maintained during installation and removal
of mechanized mining equipment. The approved ventilation plan shall
specify the minimum quantity of air, the locations where this quantity
will be provided and the ventilation controls required.
(e) In anthracite mines, the quantity of air shall be as follows:
(1) At least 1,500 cubic feet per minute reaching each working face
where coal is being mined, unless a greater quantity is required to be
specified in the approved ventilation plan.
(2) At least 5,000 cubic feet per minute passing through the last
open crosscut in each set of entries or rooms and at the intake end of
any pillar line, unless a greater quantity is required to be specified
in the approved ventilation plan.
(3) When robbing areas where air currents cannot be controlled and
air measurements cannot be obtained, the air shall have perceptible
movement.
Sec. 75.326 Mean entry air velocity.
In exhausting face ventilation systems, the mean entry air velocity
shall be at least 60 feet per minute reaching each working face where
coal is being cut, mined, drilled for blasting, or loaded, and to any
other working places as required in the approved ventilation plan. A
lower mean entry air velocity may be approved in the ventilation plan
if the lower velocity will maintain methane and respirable dust
concentrations below the applicable levels. Mean entry air velocity
shall be determined at or near the inby end of the line curtain,
ventilation tubing, or other face ventilation control devices.
Sec. 75.327 Air courses and trolley haulage systems.
(a) In any mine opened on or after March 30, 1970, or in any new
working section of a mine opened before that date, where trolley
haulage systems are maintained and where trolley wires or trolley
feeder wires are installed, an authorized representative of the
Secretary shall require enough entries or rooms as intake air courses
to limit the velocity of air currents in the haulageways to minimize
the hazards of fires and dust explosions in the haulageways.
(b) Unless the district manager approves a higher velocity, the
velocity of the air current in the trolley haulage entries shall be
limited to not more than 250 feet per minute. A higher air velocity may
be required to limit the methane content in these haulage entries or
elsewhere in the mine to less than 1.0 percent and provide an adequate
supply of oxygen.
Sec. 75.330 Face ventilation control devices.
(a) Brattice cloth, ventilation tubing and other face ventilation
control devices shall be made of flame-resistant material approved by
MSHA.
(b)(1) Ventilation control devices shall be used to provide
ventilation to dilute, render harmless, and to carry away flammable,
explosive, noxious, and harmful gases, dusts, smoke, and fumes--
(i) To each working face from which coal is being cut, mined,
drilled for blasting, or loaded; and
(ii) To any other working places as required by the approved
ventilation plan.
(2) These devices shall be installed at a distance no greater than
10 feet from the area of deepest penetration to which any portion of
the face has been advanced unless an alternative distance is specified
and approved in the ventilation plan. Alternative distances specified
shall be capable of maintaining concentrations of respirable dust,
methane, and other harmful gases below the levels specified in the
applicable sections of this chapter.
(c) When the line brattice or any other face ventilation control
device is damaged to an extent that ventilation of the working face is
inadequate, production activities in the working place shall cease
until necessary repairs
[[Page 9834]]
are made and adequate ventilation is restored.
Sec. 75.331 Auxiliary fans and tubing.
(a) When auxiliary fans and tubing are used for face ventilation,
each auxiliary fan shall be--
(1) Permissible, if the fan is electrically operated;
(2) Maintained in proper operating condition;
(3) Deenergized or shut off when no one is present on the working
section; and
(4) Located and operated to avoid recirculation of air.
(b) If a deficiency exists in any auxiliary fan system, the
deficiency shall be corrected or the auxiliary fan shall be deenergized
immediately.
(c) If the air passing through an auxiliary fan or tubing contains
1.0 percent or more methane, power to electrical equipment in the
working place and to the auxiliary fan shall be deenergized, and other
mechanized equipment in the working place shall be shut off until the
methane concentration is reduced to less than 1.0 percent.
(d) When an auxiliary fan is stopped--
(1) Line brattice or other face ventilation control devices shall
be used to maintain ventilation to affected faces; and
(2) Electrical equipment in the affected working places shall be
disconnected at the power source, and other mechanized equipment shall
be shut off until ventilation to the working place is restored.
Sec. 75.332 Working sections and working places.
(a)(1) Each working section and each area where mechanized mining
equipment is being installed or removed, shall be ventilated by a
separate split of intake air directed by overcasts, undercasts or other
permanent ventilation controls.
(2) When two or more sets of mining equipment are simultaneously
engaged in cutting, mining, or loading coal or rock from working places
within the same working section, each set of mining equipment shall be
on a separate split of intake air.
(3) For purposes of this section, a set of mining equipment
includes a single loading machine, a single continuous mining machine,
or a single longwall or shortwall mining machine.
(b)(1) Air that has passed through any area that is not examined
under Secs. 75.360, 75.361 or 75.364 of this subpart, or through an
area where second mining has been done shall not be used to ventilate
any working place. Second mining is intentional retreat mining where
pillars have been wholly or partially removed, regardless of the amount
of recovery obtained.
(2) Air that has passed by any opening of any unsealed area that is
not examined under Secs. 75.360, 75.361 or 75.364 of this subpart,
shall not be used to ventilate any working place.
Sec. 75.333 Ventilation controls.
(a) For purposes of this section, ``doors'' include any door
frames.
(b) Permanent stoppings or other permanent ventilation control
devices constructed after November 15, 1992, shall be built and
maintained--
(1) Between intake and return air courses, except temporary
controls may be used in rooms that are 600 feet or less from the
centerline of the entry from which the room was developed including
where continuous face haulage systems are used in such rooms. Unless
otherwise approved in the ventilation plan, these stoppings or controls
shall be maintained to and including the third connecting crosscut
outby the working face;
(2) To separate belt conveyor haulageways from return air courses,
except where belt entries in areas of mines developed before March 30,
1970, are used as return air courses;
(3) To separate belt conveyor haulageways from intake air courses
when the air in the intake air courses is used to provide air to active
working places. Temporary ventilation controls may be used in rooms
that are 600 feet or less from the centerline of the entry from which
the rooms were developed including where continuous face haulage
systems are used in such rooms. When continuous face haulage systems
are used, permanent stoppings or other permanent ventilation control
devices shall be built and maintained to the outby most point of travel
of the dolly or 600 feet from the point of deepest penetration in the
conveyor belt entry, whichever distance is closer to the point of
deepest penetration, to separate the continuous haulage entry from the
intake entries;
(4) To separate the primary escapeway from belt and trolley haulage
entries, as required by Sec. 75.380(g). For the purposes of
Sec. 75.380(g), the loading point for a continuous haulage system shall
be the outby most point of travel of the dolly or 600 feet from the
point of deepest penetration, whichever distance is less; and
(5) In return air courses to direct air into adjacent worked-out
areas.
(c) Personnel doors shall be constructed of noncombustible material
and shall be of sufficient strength to serve their intended purpose of
maintaining separation and permitting travel between air courses, and
shall be installed as follows in permanent stoppings constructed after
November 15, 1992:
(1) The distance between personnel doors shall be no more than 300
feet in seam heights below 48 inches and 600 feet in seam heights 48
inches or higher.
(2) The location of all personnel doors in stoppings along
escapeways shall be clearly marked so that the doors may be easily
identified by anyone traveling in the escapeway and in the entries on
either side of the doors.
(3) When not in use, personnel doors shall be closed.
(d) Doors, other than personnel doors, constructed after November
15, 1992, that are used in lieu of permanent stoppings or to control
ventilation within an air course shall be:
(1) Made of noncombustible material or coated on all accessible
surfaces with flame-retardant material having a flame-spread index of
25 or less, as tested under ASTM E162-87.
(2) Of sufficient strength to serve their intended purpose of
maintaining separation and permitting travel between or within air
courses or entries.
(3) Installed in pairs to form an airlock. When an airlock is used,
one side of the airlock shall remain closed. When not in use, both
sides shall be closed.
(e)(1)(i) Except as provided in paragraphs (e)(2), (e)(3) and
(e)(4) of this section all overcasts, undercasts, shaft partitions,
permanent stoppings, and regulators, installed after March 11, 1997,
shall be constructed in a traditionally accepted method and of
materials that have been demonstrated to perform adequately or in a
method and of materials that have been tested and shown to have a
minimum strength equal to or greater than the traditionally accepted
in-mine controls. Tests may be performed under ASTM E72-80 Section 12--
Transverse Load-Specimen Vertical, load only, or the operator may
conduct comparative in-mine tests. In-mine tests shall be designed to
demonstrate the comparative strength of the proposed construction and a
traditionally accepted in-mine control.
(ii) All overcasts, undercasts, shaft partitions, permanent
stoppings, and regulators, installed after November 15, 1992, shall be
constructed of noncombustible material. Materials that are suitable for
the construction of overcasts, undercasts, shaft partitions, permanent
stoppings, and regulators include concrete, concrete block, brick,
cinder block, tile, or steel. No ventilation controls installed after
[[Page 9835]]
November 15, 1992, shall be constructed of aluminum.
(2) In anthracite mines, permanent stoppings may be constructed of
overlapping layers of hardwood mine boards, if the stoppings are a
minimum 2 inches thick.
(3) When timbers are used to create permanent stoppings in heaving
or caving areas, the stoppings shall be coated on all accessible
surfaces with a flame-retardant material having a flame-spread index of
25 or less, as tested under ASTM E162-87, ``Surface Flammability of
Materials Using a Radiant Heat Energy Source.''
(4) In anthracite mines, doors and regulators may be constructed of
overlapping layers of hardwood boards, if the doors, door frames, and
regulators are a minimum 2 inches thick.
(f) When sealants are applied to ventilation controls, the sealant
shall have a flame-spread index of 25 or less under ASTM E162-87.
(g) Before mining is discontinued in an entry or room that is
advanced more than 20 feet from the inby rib, a crosscut shall be made
or line brattice shall be installed and maintained to provide adequate
ventilation. When conditions such as methane liberation warrant a
distance less than 20 feet, the approved ventilation plan shall specify
the location of such rooms or entries and the maximum distance they
will be developed before a crosscut is made or line brattice is
installed.
(h) All permanent ventilation controls, including seals, shall be
maintained to serve the purpose for which they were built.
Sec. 75.334 Worked-out areas and areas where pillars are being
recovered.
(a) Worked-out areas where no pillars have been recovered shall
be--
(1) Ventilated so that methane-air mixtures and other gases, dusts,
and fumes from throughout the worked-out areas are continuously diluted
and routed into a return air course or to the surface of the mine; or
(2) Sealed.
(b)(1) During pillar recovery a bleeder system shall be used to
control the air passing through the area and to continuously dilute and
move methane-air mixtures and other gases, dusts, and fumes from the
worked-out area away from active workings and into a return air course
or to the surface of the mine.
(2) After pillar recovery a bleeder system shall be maintained to
provide ventilation to the worked-out area, or the area shall be
sealed.
(c) The approved ventilation plan shall specify the following:
(1) The design and use of bleeder systems;
(2) The means to determine the effectiveness of bleeder systems;
(3) The means for adequately maintaining bleeder entries free of
obstructions such as roof falls and standing water; and
(4) The location of ventilating devices such as regulators,
stoppings and bleeder connectors used to control air movement through
the worked-out area.
(d) If the bleeder system used does not continuously dilute and
move methane-air mixtures and other gases, dusts, and fumes away from
worked-out areas into a return air course or to the surface of the
mine, or it cannot be determined by examinations or evaluations under
Sec. 75.364 that the bleeder system is working effectively, the worked-
out area shall be sealed.
(e) Each mining system shall be designed so that each worked-out
area can be sealed. The approved ventilation plan shall specify the
location and the sequence of construction of proposed seals.
(f) In place of the requirements of paragraphs (a) and (b) of this
section, for mines with a demonstrated history of spontaneous
combustion, or that are located in a coal seam determined to be
susceptible to spontaneous combustion, the approved ventilation plan
shall specify the following:
(1) Measures to detect methane, carbon monoxide, and oxygen
concentrations during and after pillar recovery, and in worked-out
areas where no pillars have been recovered, to determine if the areas
must be ventilated or sealed.
(2) Actions that will be taken to protect miners from the hazards
of spontaneous combustion.
(3) If a bleeder system will not be used, the methods that will be
used to control spontaneous combustion, accumulations of methane-air
mixtures, and other gases, dusts, and fumes in the worked-out area.
Sec. 75.335 Construction of seals.
(a)(1) Each seal constructed after November 15, 1992, shall be--
(i) Constructed of solid concrete blocks at least 6 by 8 by 16
inches, laid in a transverse pattern with mortar between all joints;
(ii) Hitched into solid ribs to a depth of at least 4 inches and
hitched at least 4 inches into the floor;
(iii) At least 16 inches thick. When the thickness of the seal is
less than 24 inches and the width is greater than 16 feet or the height
is greater than 10 feet, a pilaster shall be interlocked near the
center of the seal. The pilaster shall be at least 16 inches by 32
inches; and
(iv) Coated on all accessible surfaces with flame-retardant
material that will minimize leakage and that has a flame-spread index
of 25 or less, as tested under ASTM E162-87, ``Surface Flammability of
Materials Using a Radiant Heat Energy Source.''
(2) Alternative methods or materials may be used to create a seal
if they can withstand a static horizontal pressure of 20 pounds per
square inch provided the method of installation and the material used
approved in the ventilation plan. If the alternative methods or
materials include the use of timbers, the timbers also shall be coated
on all accessible surfaces with flame-retardant material having a
flame-spread index 25 or less, as tested under ASTM E162-87.
(b) A sampling pipe or pipes shall be installed in each set of
seals for a worked-out area. Each pipe shall--
(1) Extend into the sealed area a sufficient distance (at least 15
feet) to obtain a representative sample from behind the seal;
(2) Be equipped with a cap or shut-off valve; and
(3) Be installed with the sampling end of the pipe about 12 inches
from the roof.
(c)(1) A corrosion-resistant water pipe or pipes shall be installed
in seals at the low points of the area being sealed and at all other
locations necessary when water accumulation within the sealed area is
possible; and
(2) Each water pipe shall have a water trap installed on the outby
side of the seal.
Sec. 75.340 Underground electrical installations.
(a) Underground transformer stations, battery charging stations,
substations, rectifiers, and water pumps shall be housed in
noncombustible structures or areas or be equipped with a fire
suppression system meeting the requirements of Sec. 75.1107-3 through
Sec. 75.1107-16.
(1) When a noncombustible structure or area is used, these
installations shall be--
(i) Ventilated with intake air that is coursed into a return air
course or to the surface and that is not used to ventilate working
places; or
(ii) Ventilated with intake air that is monitored for carbon
monoxide or smoke by an AMS installed and operated according to
Sec. 75.351. Monitoring of intake air ventilating battery charging
stations shall be done with sensors not affected by hydrogen; or
(iii) Ventilated with intake air and equipped with sensors to
monitor for heat and for carbon monoxide or smoke. Monitoring of intake
air ventilating battery charging stations shall be done
[[Page 9836]]
with sensors not affected by hydrogen. The sensors shall deenergize
power to the installation, activate a visual and audible alarm located
outside of and on the intake side of the enclosure, and activate doors
that will automatically close when either of the following occurs:
(A) The temperature in the noncombustible structure reaches 165
deg.F; or
(B) The carbon monoxide concentration reaches 10 parts per million
above the ambient level for the area, or the optical density of smoke
reaches 0.022 per meter. At least every 31 days, sensors installed to
monitor for carbon monoxide shall be calibrated with a known
concentration of carbon monoxide and air sufficient to activate the
closing door, or each smoke sensor shall be tested to determine that it
functions correctly.
(2) When a fire suppression system is used, these installations
shall be--
(i) Ventilated with intake air that is coursed into a return air
course or to the surface and that is not used to ventilate working
places; or
(ii) Ventilated with intake air that is monitored for carbon
monoxide or smoke by an AMS installed and operated according to
Sec. 75.351. Monitoring of intake air ventilating battery charging
stations shall be done with sensors not affected by hydrogen.
(b) This section does not apply to--
(1) Rectifiers and power centers with transformers that are either
dry-type or contain nonflammable liquid, if they are located at or near
the section and are moved as the working section advances or retreats;
(2) Submersible pumps;
(3) Permissible pumps and associated permissible switchgear;
(4) Pumps located on or near the section and that are moved as the
working section advances or retreats;
(5) Pumps installed in anthracite mines; and
(6) Small portable pumps.
Sec. 75.341 Direct-fired intake air heaters.
(a) If any system used to heat intake air malfunctions, the heaters
affected shall switch off automatically.
(b) Thermal overload devices shall protect the blower motor from
overheating.
(c) The fuel supply shall turn off automatically if a flame-out
occurs.
(d) Each heater shall be located or guarded to prevent contact by
persons and shall be equipped with a screen at the inlet to prevent
combustible materials from passing over the burner units.
(e) If intake air heaters use liquefied fuel systems--
(1) Hydrostatic relief valves installed on vaporizers and on
storage tanks shall be vented; and
(2) Fuel storage tanks shall be located or protected to prevent
fuel from leaking into the mine.
(f) Following any period of 8 hours or more during which a heater
does not operate, the heater and its associated components shall be
examined within its first hour of operation. Additionally, each heater
and its components shall be examined at least once each shift that the
heater operates. The examination shall include measurement of the
carbon monoxide concentration at the bottom of each shaft, slope, or in
the drift opening where air is being heated. The measurements shall be
taken by a person designated by the operator or by a carbon monoxide
sensor that is calibrated with a known concentration of carbon monoxide
and air at least once every 31 days. When the carbon monoxide
concentration at this location reaches 50 parts per million, the heater
causing the elevated carbon monoxide level shall be shut down.
Sec. 75.342 Methane monitors.
(a)(1) MSHA approved methane monitors shall be installed on all
face cutting machines, continuous miners, longwall face equipment,
loading machines, and other mechanized equipment used to extract or
load coal within the working place.
(2) The sensing device for methane monitors on longwall shearing
machines shall be installed at the return air end of the longwall face.
An additional sensing device also shall be installed on the longwall
shearing machine, downwind and as close to the cutting head as
practicable. An alternative location or locations for the sensing
device required on the longwall shearing machine may be approved in the
ventilation plan.
(3) The sensing devices of methane monitors shall be installed as
close to the working face as practicable.
(4) Methane monitors shall be maintained in permissible and proper
operating condition and shall be calibrated with a known air-methane
mixture at least once every 31 days. To assure that methane monitors
are properly maintained and calibrated, the operator shall:
(i) Use persons properly trained in the maintenance, calibration,
and permissibility of methane monitors to calibrate and maintain the
devices.
(ii) Maintain a record of all calibration tests of methane
monitors. Records shall be maintained in a secure book that is not
susceptible to alteration or electronically in a computer system so as
to be secure and not susceptible to alteration.
(iii) Retain the record of calibration tests for 1 year from the
date of the test. Records shall be retained at a surface location at
the mine and made available for inspection by authorized
representatives of the Secretary and the representative of miners.
(b)(1) When the methane concentration at any methane monitor
reaches 1.0 percent the monitor shall give a warning signal.
(2) The warning signal device of the methane monitor shall be
visible to a person who can deenergize the equipment on which the
monitor is mounted.
(c) The methane monitor shall automatically deenergize the machine
on which it is mounted when--
(1) The methane concentration at any methane monitor reaches 2.0
percent; or
(2) The monitor is not operating properly.
Sec. 75.343 Underground shops.
(a) Underground shops shall be equipped with an automatic fire
suppression system meeting the requirements of Sec. 75.1107-3 through
Sec. 75.1107-16, or be enclosed in a noncombustible structure or area.
(b) Underground shops shall be ventilated with intake air that is
coursed directly into a return air course.
Sec. 75.344 Compressors.
(a) Except compressors that are components of equipment such as
locomotives and rock dusting machines and compressors of less than 5
horsepower, electrical compressors including those that may start
automatically shall be:
(1) Continuously attended by a person designated by the operator
who can see the compressor at all times during its operation. Any
designated person attending the compressor shall be capable of
activating the fire suppression system and deenergizing or shutting-off
the compressor in the event of a fire; or,
(2) Enclosed in a noncombustible structure or area which is
ventilated by intake air coursed directly into a return air course or
to the surface and equipped with sensors to monitor for heat and for
carbon monoxide or smoke. The sensors shall deenergize power to the
compressor, activate a visual and audible alarm located outside of and
on the intake side of the enclosure, and activate doors to
automatically enclose the noncombustible structure or area when either
of the following occurs:
(i) The temperature in the noncombustible structure or area reaches
165 deg.F.
[[Page 9837]]
(ii) The carbon monoxide concentration reaches 10 parts per million
above the ambient level for the area, or the optical density of smoke
reaches 0.022 per meter. At least once every 31 days, sensors installed
to monitor for carbon monoxide shall be calibrated with a known
concentration of carbon monoxide and air sufficient to activate the
closing door, and each smoke sensor shall be tested to determine that
it functions correctly.
(b) Compressors, except those exempted in paragraph (a), shall be
equipped with a heat activated fire suppression system meeting the
requirements of 75.1107-3 through 75.1107-16.
(c) Two portable fire extinguishers or one extinguisher having at
least twice the minimum capacity specified for a portable fire
extinguisher in Sec. 75.1100-1(e) shall be provided for each
compressor.
(d) In addition to electrical compressors, this section shall apply
to diesel compressors.
(e) Notwithstanding the requirements of Sec. 75.1107-4, upon
activation of any fire suppression system used under paragraph (b) of
this section, the compressor shall be automatically deenergized or
automatically shut off.
Sec. 75.350 Air courses and belt haulage entries.
In any coal mine opened after March 30, 1970, the entries used as
intake and return air courses shall be separated from belt haulage
entries, and each operator of such mine shall limit the velocity of the
air coursed through belt haulage entries to the amount necessary to
provide an adequate supply of oxygen in such entries, and to insure
that the air therein shall contain less than 1.0 volume per centum of
methane, and such air shall not be used to ventilate active working
places. Whenever an authorized representative of the Secretary finds,
in the case of any coal mine opened on or prior to March 30, 1970, that
has been developed with more than two entries, that the conditions in
the entries, other than belt haulage entries, are such as to permit
adequately the coursing of intake or return air through such entries:
(a) The belt haulage entries shall not be used to ventilate, unless
such entries are necessary to ventilate, active working places, and
(b) When the belt haulage entries are not necessary to ventilate
the active working places, the operator of such mine shall limit the
velocity of the air coursed through the belt haulage entries to the
amount necessary to provide an adequate supply of oxygen in such
entries, and to assure that air therein shall contain less than 1.0
volume per centum of methane.
Sec. 75.351 Atmospheric monitoring system (AMS).
(a) Minimum requirements. An AMS shall consist of sensors to
monitor the mine atmosphere and instruments at a surface location
designated by the operator to receive information from the monitoring
sensors. Each AMS installed in accordance with Secs. 75.323(d)(1)(ii),
75.340(a)(2) and 75.362(f) shall do the following:
(1) Monitor for circuit continuity and sensor function, and
identify at the designated surface location any activated or
malfunctioning sensor.
(2) Signal a designated surface location at the mine when any
interruption of circuit continuity occurs or any sensor malfunctions.
(3) Signal affected working sections and the designated surface
location when--
(i) The carbon monoxide concentration at any carbon monoxide sensor
reaches 5 parts per million above the established ambient level for
that area; or
(ii) The methane concentration at any methane monitoring station
exceeds the maximum allowable concentration as specified for that
location in Sec. 75.323.
(4) Activate alarms at a designated surface location and affected
working sections when the carbon monoxide concentration at any carbon
monoxide sensor reaches 10 parts per million above the established
ambient level for the area or when the optical density of smoke at any
smoke sensor reaches 0.05 per meter.
(b) Return splits. (1) If used to monitor return air splits under
Sec. 75.362(f), AMS sensors shall monitor the mine atmosphere for
percentage of methane in each return split of air from each working
section between the last working place, or longwall or shortwall face,
ventilated by that air split and the junction of that return air split
with another air split, seal, or worked-out area. If auxiliary fans and
tubing are used, the sensor also shall be located outby the auxiliary
fan discharge.
(2) If used to monitor air splits under Sec. 75.323(d)(1)(ii), AMS
sensors shall monitor the mine atmosphere at the following locations:
(i) In the return air course opposite the section loading point or,
if auxiliary fans and tubing are used, in the return air course outby
the auxiliary fans and a point opposite the section loading point.
(ii) Immediately inby the location where the split of air meets
another split of air, or inby the location where the split of air is
used to ventilate seals or worked-out areas.
(c) Electrical installations. If used to monitor the intake air
ventilating underground transformer stations, battery charging
stations, substations, rectifiers, or water pumps under
Sec. 75.340(a)(2), at least one sensor shall be installed to monitor
the mine atmosphere for carbon monoxide or smoke at least 50 feet and
no more than 100 feet downstream in the direction of air flow.
(d) Signals and alarms. (1) A person designated by the operator
shall be at a surface location where the signals and alarms from the
AMS can always be seen or heard while anyone is underground. This
person shall have access to two-way communication with working sections
and with other identifiable duty stations underground. A mine map
showing the underground monitoring system shall be posted at the
surface location.
(2) If a signal from any AMS sensor is activated, the monitor
producing the signal shall be identified, an examination shall be made
to determine the cause of the activation, and appropriate action shall
be taken.
(e) Sensors. (1) Each carbon monoxide sensor shall be capable of
detecting carbon monoxide in air at a level of 1 part per
million throughout the operating range.
(2) Each methane sensor shall be capable of detecting 1.0 percent
methane in air with an accuracy of 0.2 percent methane.
(3) Each smoke sensor shall be capable of detecting the optical
density of smoke with an accuracy of 0.005 per meter.
(f) Testing and calibration. At least once every 31 days--
(1) Each carbon monoxide sensor shall be calibrated with a known
concentration of carbon monoxide and air sufficient to activate an
alarm;
(2) Each smoke sensor shall be functionally tested;
(3) Each methane sensor shall be calibrated with a known methane-
air mixture; and
(4) Each oxygen sensor shall be calibrated with air having a known
oxygen concentration.
(g) Intrinsic Safety. Components of AMS installed in areas where
permissible equipment is required shall be intrinsically safe.
(h) Recordkeeping. If a signal device or alarm is activated, a
record shall be made of the date, time, type of sensor, and the reason
for its activation. Also the maximum concentration detected at
[[Page 9838]]
the sensor producing the signal shall be recorded.
(i) Retention period. Records shall be retained for at least 1 year
at a surface location at the mine and made available for inspection by
authorized representatives of the Secretary and representatives of
miners.
Sec. 75.352 Return air courses.
Entries used as return air courses shall be separated from belt
haulage entries by permanent ventilation controls.
Sec. 75.360 Preshift examination.
(a)(1) Except as provided in paragraph (a)(2) of this section, a
certified person designated by the operator shall make a preshift
examination within 3 hours preceding the beginning of any 8-hour
interval during which any person is scheduled to work or travel
underground. The operator shall establish the 8-hour intervals of time
subject to the required preshift examinations. No person other than
certified examiners may enter or remain in any underground area unless
a preshift examination has been completed for the established 8-hour
period.
(2) Preshift examinations of areas where pumpers are scheduled to
work or travel shall not be required prior to the pumper entering the
areas if the pumper is a certified person and the pumper conducts an
examination for hazardous conditions, tests for methane and oxygen
deficiency and determines if the air is moving in its proper direction
in the area where the pumper works or travels. The examination of the
area must be completed before the pumper performs any other work. A
record of all hazardous conditions found by the pumper shall be made
and retained in accordance with Sec. 75.363.
(b) The person conducting the preshift examination shall examine
for hazardous conditions, test for methane and oxygen deficiency, and
determine if the air is moving in its proper direction at the following
locations:
(1) Roadways, travelways and track haulageways where persons are
scheduled, prior to the beginning of the preshift examination, to work
or travel during the oncoming shift.
(2) Belt conveyors that will be used to transport persons during
the oncoming shift and the entries in which these belt conveyors are
located.
(3) Working sections and areas where mechanized mining equipment is
being installed or removed, if anyone is scheduled to work on the
section or in the area during the oncoming shift. The scope of the
examination shall include the working places, approaches to worked-out
areas and ventilation controls on these sections and in these areas,
and the examination shall include tests of the roof, face and rib
conditions on these sections and in these areas.
(4) Approaches to worked-out areas along intake air courses and at
the entries used to carry air into worked-out areas if the intake air
passing the approaches is used to ventilate working sections where
anyone is scheduled to work during the oncoming shift. The examination
of the approaches to the worked-out areas shall be made in the intake
air course immediately inby and outby each entry used to carry air into
the worked-out area. An examination of the entries used to carry air
into the worked-out areas shall be conducted at a point immediately
inby the intersection of each entry with the intake air course.
(5) Seals along intake air courses where intake air passes by a
seal to ventilate working sections where anyone is scheduled to work
during the oncoming shift.
(6)(i) Entries and rooms developed after November 15, 1992, and
developed more than 2 crosscuts off an intake air course without
permanent ventilation controls where intake air passes through or by
these entries or rooms to reach a working section where anyone is
scheduled to work during the oncoming shift; and,
(ii) Entries and rooms developed after November 15, 1992, and
driven more than 20 feet off an intake air course without a crosscut
and without permanent ventilation controls where intake air passes
through or by these entries or rooms to reach a working section where
anyone is scheduled to work during the oncoming shift.
(7) Where unattended diesel equipment is to operate or areas where
trolley wires or trolley feeder wires are to be or will remain
energized during the oncoming shift.
(8) High spots along intake air courses where methane is likely to
accumulate, if equipment will be operated in the area during the shift.
(9) Underground electrical installations referred to in
Sec. 75.340(a), except those pumps listed in Sec. 75.340 (b)(2) through
(b)(6), and areas where compressors subject to Sec. 75.344 are
installed if the electrical installation or compressor is or will be
energized during the shift.
(10) Other areas where work or travel during the oncoming shift is
scheduled prior to the beginning of the preshift examination.
(c) The person conducting the preshift examination shall determine
the volume of air entering each of the following areas if anyone is
scheduled to work in the areas during the oncoming shift:
(1) In the last open crosscut of each set of entries or rooms on
each working section and areas where mechanized mining equipment is
being installed or removed. The last open crosscut is the crosscut in
the line of pillars containing the permanent stoppings that separate
the intake air courses and the return air courses.
(2) On each longwall or shortwall in the intake entry or entries at
the intake end of the longwall or shortwall face immediately outby the
face and the velocity of air at each end of the face at the locations
specified in the approved ventilation plan.
(3) At the intake end of any pillar line--
(i) If a single split of air is used, in the intake entry furthest
from the return air course, immediately outby the first open crosscut
outby the line of pillars being mined; or
(ii) If a split system is used, in the intake entries of each split
immediately inby the split point.
(d) The district manager may require the certified person to
examine other areas of the mine or examine for other hazards during the
preshift examination.
(e) Certification. At each working place examined, the person doing
the preshift examination shall certify by initials, date, and the time,
that the examination was made. In areas required to be examined outby a
working section, the certified person shall certify by initials, date,
and the time at enough locations to show that the entire area has been
examined.
(f) Recordkeeping. A record of the results of each preshift
examination, including a record of hazardous conditions and their
locations found by the examiner during each examination and of the
results and locations of air and methane measurements, shall be made on
the surface before any persons, other than certified persons conducting
examinations required by this subpart, enter any underground area of
the mine. The results of methane tests shall be recorded as the
percentage of methane measured by the examiner. The record shall be
made by the certified person who made the examination or by a person
designated by the operator. If the record is made by someone other than
the examiner, the examiner shall verify the record by initials and date
by or at the end of the shift for which the examination was made. A
record shall also be made by a certified person of the action taken to
correct hazardous conditions found during the preshift
[[Page 9839]]
examination. All preshift and corrective action records shall be
countersigned by the mine foreman or equivalent mine official by the
end of the mine foreman's or equivalent mine official's next regularly
scheduled working shift. The records required by this section shall be
made in a secure book that is not susceptible to alteration or
electronically in a computer system so as to be secure and not
susceptible to alteration.
(g) Retention period. Records shall be retained at a surface
location at the mine for at least 1 year and shall be made available
for inspection by authorized representatives of the Secretary and the
representative of miners.
Sec. 75.361 Supplemental examination.
(a) Except for certified persons conducting examinations required
by this subpart, within 3 hours before anyone enters an area in which a
preshift examination has not been made for that shift, a certified
person shall examine the area for hazardous conditions, determine
whether the air is traveling in its proper direction and at its normal
volume, and test for methane and oxygen deficiency.
(b) Certification. At each working place examined, the person
making the supplemental examination shall certify by initials, date,
and the time, that the examination was made. In areas required to be
examined outby a working section, the certified person shall certify by
initials, date, and the time at enough locations to show that the
entire area has been examined.
Sec. 75.362 On-shift examination.
(a) (1) At least once during each shift, or more often if necessary
for safety, a certified person designated by the operator shall conduct
an on-shift examination of each section where anyone is assigned to
work during the shift and any area where mechanized mining equipment is
being installed or removed during the shift. The certified person shall
check for hazardous conditions, test for methane and oxygen deficiency,
and determine if the air is moving in its proper direction.
(2) A person designated by the operator shall conduct an
examination to assure compliance with the respirable dust control
parameters specified in the mine ventilation plan. In those instances
when a shift change is accomplished without an interruption in
production on a section, the examination shall be made anytime within 1
hour of the shift change. In those instances when there is an
interruption in production during the shift change, the examination
shall be made before production begins on a section. Deficiencies in
dust controls shall be corrected before production begins or resumes.
The examination shall include air quantities and velocities, water
pressures and flow rates, excessive leakage in the water delivery
system, water spray numbers and orientations, section ventilation and
control device placement, and any other dust suppression measures
required by the ventilation plan. Additional measurements of the air
velocity and quantity, water pressure and flow rates are not required
if continuous monitoring of these controls is used and indicates that
the dust controls are functioning properly.
(b) During each shift that coal is produced, a certified person
shall examine for hazardous conditions along each belt conveyor
haulageway where a belt conveyor is operated. This examination may be
conducted at the same time as the preshift examination of belt
conveyors and belt conveyor haulageways, if the examination is
conducted within 3 hours before the oncoming shift.
(c) Persons conducting the on-shift examination shall determine at
the following locations:
(1) The volume of air in the last open crosscut of each set of
entries or rooms on each section and areas where mechanized mining
equipment is being installed or removed. The last open crosscut is the
crosscut in the line of pillars containing the permanent stoppings that
separate the intake air courses and the return air courses.
(2) The volume of air on a longwall or shortwall, including areas
where longwall or shortwall equipment is being installed or removed, in
the intake entry or entries at the intake end of the longwall or
shortwall.
(3) The velocity of air at each end of the longwall or shortwall
face at the locations specified in the approved ventilation plan.
(4) The volume of air at the intake end of any pillar line--
(i) Where a single split of air is used in the intake entry
furthest from the return air course immediately outby the first open
crosscut outby the line of pillars being mined; or
(ii) Where a split system is used in the intake entries of each
split immediately inby the split point.
(d) (1) A qualified person shall make tests for methane--
(i) At the start of each shift at each working place before
electrically operated equipment is energized; and
(ii) Immediately before equipment is energized, taken into, or
operated in a working place; and
(iii) At 20-minute intervals, or more often if required in the
approved ventilation plan at specific locations, during the operation
of equipment in the working place.
(2) These methane tests shall be made at the face from under
permanent roof support, using extendable probes or other acceptable
means. When longwall or shortwall mining systems are used, these
methane tests shall be made at the shearer, the plow, or the cutting
head. When mining has been stopped for more than 20 minutes, methane
tests shall be conducted prior to the start up of equipment.
(e) If auxiliary fans and tubing are used, they shall be inspected
frequently.
(f) During each shift that coal is produced and at intervals not
exceeding 4 hours, tests for methane shall be made by a certified
person or by an atmospheric monitoring system (AMS) in each return
split of air from each working section between the last working place,
or longwall or shortwall face, ventilated by that split of air and the
junction of the return air split with another air split, seal, or
worked-out area. If auxiliary fans and tubing are used, the tests shall
be made at a location outby the auxiliary fan discharge.
(g) Certification. (1) The person conducting the on-shift
examination in belt haulage entries shall certify by initials, date,
and time that the examination was made. The certified person shall
certify by initials, date, and the time at enough locations to show
that the entire area has been examined.
(2) The person directing the on-shift examination to assure
compliance with the respirable dust control parameters specified in the
mine ventilation plan shall certify by initials, date, and time that
the examination was made.
Sec. 75.363 Hazardous conditions; posting, correcting and recording.
(a) Any hazardous condition found by the mine foreman or equivalent
mine official, assistant mine foreman or equivalent mine official, or
other certified persons designated by the operator for the purposes of
conducting examinations under this subpart D, shall be posted with a
conspicuous danger sign where anyone entering the areas would pass. A
hazardous condition, other than one detected during a preshift
examination or an examination conducted following a fan stoppage and
restart under Sec. 75.313(d)(1)(i), shall be corrected immediately or
the area shall remain posted until the hazardous condition is
corrected. If the condition creates an imminent danger, everyone except
those persons referred to in
[[Page 9840]]
section 104(c) of the Act shall be withdrawn from the area affected to
a safe area until the hazardous condition is corrected. Only persons
designated by the operator to correct or evaluate the condition may
enter the posted area.
(b) A record shall be made of any hazardous condition found. This
record shall be kept in a book maintained for this purpose on the
surface at the mine. The record shall be made by the completion of the
shift on which the hazardous condition is found and shall include the
nature and location of the hazardous condition and the corrective
action taken. This record shall not be required for shifts when no
hazardous conditions are found or for hazardous conditions found during
the preshift or weekly examinations inasmuch as these examinations have
separate recordkeeping requirements.
(c) The record shall be made by the certified person who conducted
the examination or a person designated by the operator. If made by a
person other than the certified person, the certified person shall
verify the record by initials and date by or at the end of the shift
for which the examination was made. Records shall be countersigned by
the mine foreman or equivalent mine official by the end of the mine
foreman's or equivalent mine official's next regularly scheduled
working shift. The record shall be made in a secure book that is not
susceptible to alteration or electronically in a computer system so as
to be secure and not susceptible to alteration.
(d) Retention period. Records shall be retained at a surface
location at the mine for at least 1 year and shall be made available
for inspection by authorized representatives of the Secretary and the
representative of miners.
Sec. 75.364 Weekly examination.
(a) Worked-out areas. (1) At least every 7 days, a certified person
shall examine unsealed worked-out areas where no pillars have been
recovered by traveling to the area of deepest penetration; measuring
methane and oxygen concentrations and air quantities and making tests
to determine if the air is moving in the proper direction in the area.
The locations of measurement points where tests and measurements will
be performed shall be included in the mine ventilation plan and shall
be adequate in number and location to assure ventilation and air
quality in the area. Air quantity measurements shall also be made where
the air enters and leaves the worked-out area. An alternative method of
evaluating the ventilation of the area may be approved in the
ventilation plan.
(2) At least every 7 days, a certified person shall evaluate the
effectiveness of bleeder systems required by Sec. 75.334 as follows:
(i) Measurements of methane and oxygen concentrations and air
quantity and a test to determine if the air is moving in its proper
direction shall be made where air enters the worked-out area.
(ii) Measurements of methane and oxygen concentrations and air
quantity and a test to determine if the air is moving in the proper
direction shall be made immediately before the air enters a return
split of air.
(iii) At least one entry of each set of bleeder entries used as
part of a bleeder system under Sec. 75.334 shall be traveled in its
entirety. Measurements of methane and oxygen concentrations and air
quantities and a test to determine if the air is moving in the proper
direction shall be made at the measurement point locations specified in
the mine ventilation plan to determine the effectiveness of the bleeder
system.
(iv) In lieu of the requirements of paragraphs (a)(2)(i) and (iii)
of this section, an alternative method of evaluation may be specified
in the ventilation plan provided the alternative method results in
proper evaluation of the effectiveness of the bleeder system.
(b) Hazardous conditions. At least every 7 days, an examination for
hazardous conditions at the following locations shall be made by a
certified person designated by the operator:
(1) In at least one entry of each intake air course, in its
entirety, so that the entire air course is traveled.
(2) In at least one entry of each return air course, in its
entirety, so that the entire air course is traveled.
(3) In each longwall or shortwall travelway in its entirety, so
that the entire travelway is traveled.
(4) At each seal along return and bleeder air courses and at each
seal along intake air courses not examined under Sec. 75.360(b)(5).
(5) In each escapeway so that the entire escapeway is traveled.
(6) On each working section not examined under Sec. 75.360(b)(3)
during the previous 7 days.
(7) At each water pump not examined during a preshift examination
conducted during the previous 7 days.
(c) Measurements and tests. At least every 7 days, a certified
person shall--
(1) Determine the volume of air entering the main intakes and in
each intake split;
(2) Determine the volume of air and test for methane in the last
open crosscut in any pair or set of developing entries or rooms, in the
return of each split of air immediately before it enters the main
returns, and where the air leaves the main returns; and
(3) Test for methane in the return entry nearest each set of seals
immediately after the air passes the seals.
(d) Hazardous conditions shall be corrected immediately. If the
condition creates an imminent danger, everyone except those persons
referred to in Sec. 104(c) of the Act shall be withdrawn from the area
affected to a safe area until the hazardous condition is corrected.
(e) The weekly examination may be conducted at the same time as the
preshift or on-shift examinations.
(f) (1) The weekly examination is not required during any 7 day
period in which no one enters any underground area of the mine.
(2) Except for certified persons required to make examinations, no
one shall enter any underground area of the mine if a weekly
examination has not been completed within the previous 7 days.
(g) Certification. The person making the weekly examinations shall
certify by initials, date, and the time that the examination was made.
Certifications and times shall appear at enough locations to show that
the entire area has been examined.
(h) Recordkeeping. At the completion of any shift during which a
portion of a weekly examination is conducted, a record of the results
of each weekly examination, including a record of hazardous conditions
found during each examination and their locations, the corrective
action taken, and the results and location of air and methane
measurements, shall be made. The results of methane tests shall be
recorded as the percentage of methane measured by the examiner. The
record shall be made by the person making the examination or a person
designated by the operator. If made by a person other than the
examiner, the examiner shall verify the record by the initials and date
by or at the end of the shift for which the examination was made. The
record shall be countersigned by the mine foreman or equivalent mine
official by the end of the mine foreman's or equivalent mine official's
next regularly scheduled working shift. The records required by this
section shall be made in a secure book that is not susceptible to
alteration or electronically in a computer system so as to be secure
and not susceptible to alteration.
(i) Retention period. Records shall be retained at a surface
location at the mine for at least 1 year and shall be made available
for inspection by authorized
[[Page 9841]]
representatives of the Secretary and the representative of miners.
Sec. 75.370 Mine ventilation plan; submission and approval.
(a) (1) The operator shall develop and follow a ventilation plan
approved by the district manager. The plan shall be designed to control
methane and respirable dust and shall be suitable to the conditions and
mining system at the mine. The ventilation plan shall consist of two
parts, the plan content as prescribed in Sec. 75.371 and the
ventilation map with information as prescribed in Sec. 75.372. Only
that portion of the map which contains information required under
Sec. 75.371 will be subject to approval by the district manager.
(2) The proposed ventilation plan and any revision to the plan
shall be submitted in writing to the district manager. When revisions
to a ventilation plan are proposed, only the revised pages, maps, or
sketches of the plan need to be submitted. When required in writing by
the district manager, the operator shall submit a fully revised plan by
consolidating the plan and all revisions in an orderly manner and by
deleting all outdated material.
(3) (i) The mine operator shall notify the representative of miners
at least 5 days prior to submission of a mine ventilation plan and any
revision to a mine ventilation plan. If requested, the mine operator
shall provide a copy to the representative of miners at the time of
notification. In the event of a situation requiring immediate action on
a plan revision, notification of the revision shall be given, and if
requested, a copy of the revision shall be provided, to the
representative of miners by the operator at the time of submittal;
(ii) A copy of the proposed ventilation plan, and a copy of any
proposed revision, submitted for approval shall be made available for
inspection by the representative of miners; and
(iii) A copy of the proposed ventilation plan, and a copy of any
proposed revision, submitted for approval shall be posted on the mine
bulletin board at the time of submittal. The proposed plan or proposed
revision shall remain posted until it is approved, withdrawn or denied.
(b) Following receipt of the proposed plan or proposed revision,
the representative of miners may submit timely comments to the district
manager, in writing, for consideration during the review process. A
copy of these comments shall also be provided to the operator by the
district manager upon request.
(c) (1) The district manager will notify the operator in writing of
the approval or denial of approval of a proposed ventilation plan or
proposed revision. A copy of this notification will be sent to the
representative of miners by the district manager.
(2) If the district manager denies approval of a proposed plan or
revision, the deficiencies of the plan or revision shall be specified
in writing and the operator will be provided an opportunity to discuss
the deficiencies with the district manager.
(d) No proposed ventilation plan shall be implemented before it is
approved by the district manager. Any intentional change to the
ventilation system that alters the main air current or any split of the
main air current in a manner that could materially affect the safety
and health of the miners, or any change to the information required in
Sec. 75.371 shall be submitted to and approved by the district manager
before implementation.
(e) Before implementing an approved ventilation plan or a revision
to a ventilation plan, persons affected by the revision shall be
instructed by the operator in its provisions.
(f) The approved ventilation plan and any revisions shall be--
(1) Provided upon request to the representative of miners by the
operator following notification of approval;
(2) Made available for inspection by the representative of miners;
and
(3) Posted on the mine bulletin board within 1 working day
following notification of approval. The approved plan and revisions
shall remain posted on the bulletin board for the period that they are
in effect.
(g) The ventilation plan for each mine shall be reviewed every 6
months by an authorized representative of the Secretary to assure that
it is suitable to current conditions in the mine.
Sec. 75.371 Mine ventilation plan; contents.
The mine ventilation plan shall contain the information described
below and any additional provisions required by the district manager:
(a) The mine name, company name, mine identification number, and
the name of the individual submitting the plan information.
(b) Planned main mine fan stoppages, other than those scheduled for
testing, maintenance or adjustment, including procedures to be followed
during these stoppages and subsequent restarts (see Sec. 75.311(a)) and
the type of device to be used for monitoring main mine fan pressure, if
other than a pressure recording device (see 75.310(a)(4)).
(c) Methods of protecting main mine fans and associated components
from the forces of an underground explosion if a 15-foot offset from
the nearest side of the mine opening is not provided (see
Sec. 75.310(a)(6)); and the methods of protecting main mine fans and
intake air openings if combustible material will be within 100 feet of
the area surrounding the fan or these openings (see Sec. 75.311(f)).
(d) Persons that will be permitted to enter the mine, the work
these persons will do while in the mine, and electric power circuits
that will be energized when a back-up fan system is used that does not
provide the ventilating quantity provided by the main mine fan (see
Sec. 75.311(c)).
(e) The locations and operating conditions of booster fans
installed in anthracite mines (see Sec. 75.302).
(f) Section and face ventilation systems used, including drawings
illustrating how each system is used, and a description of each
different dust suppression system used on equipment on working
sections.
(g) Locations where the air quantities must be greater than 3,000
cubic feet per minute (see Sec. 75.325(a)(1)).
(h) In anthracite mines, locations where the air quantities must be
greater than 1,500 cubic feet per minute (see Sec. 75.325(e)(1)).
(i) Working places and working faces other than those where coal is
being cut, mined, drilled for blasting or loaded, where a minimum air
quantity will be maintained, and the air quantity at those locations
(see Sec. 75.325(a)(1)).
(j) The operating volume of machine mounted dust collectors or
diffuser fans, if used (see Sec. 75.325(a)(3)).
(k) The minimum mean entry air velocity in exhausting face
ventilation systems where coal is being cut, mined, drilled for
blasting, or loaded, if the velocity will be less than 60 feet per
minute. Other working places where coal is not being cut, mined,
drilled for blasting or loaded, where at least 60 feet per minute or
some other minimum mean entry air velocity will be maintained (see
Sec. 75.326).
(l) The maximum distance if greater than 10 feet from each working
face at which face ventilation control devices will be installed (see
Sec. 75.330(b)(2)). The working places other than those where coal is
being cut, mined, drilled for blasting or loaded, where face
ventilation control devices will be used (see Sec. 75.330(b)(1)(ii).
(m) The volume of air required in the last open crosscut or the
quantity of air reaching the pillar line if greater than 9,000 cubic
feet per minute (see Sec. 75.325(b)).
[[Page 9842]]
(n) In anthracite mines, the volume of air required in the last
open crosscut or the quantity of air reaching the pillar line if
greater than 5,000 cubic feet per minute (see Sec. 75.325(e)(2)).
(o) Locations where separations of intake and return air courses
will be built and maintained to other than the third connecting
crosscut outby each working face (see Sec. 75.333(b)(1)).
(p) The volume of air required at the intake to the longwall
sections, if different than 30,000 cubic feet per minute (see
Sec. 75.325(c)).
(q) The velocities of air on a longwall or shortwall face, and the
locations where the velocities must be measured (see
Sec. 75.325(c)(2)).
(r) The minimum quantity of air that will be provided during the
installation and removal of mechanized mining equipment, the location
where this quantity will be provided, and the ventilation controls that
will be used. (see Sec. 75.325(d)).
(s) The locations and frequency of the methane tests if required
more often by Sec. 75.362(d)(1)(iii) (see Sec. 75.362 (d)(1)(iii).
(t) The locations where samples for ``designated areas'' will be
collected, including the specific location of each sampling device, and
the respirable dust control measures used at the dust generating
sources for these locations (see Sec. 70.208 of this chapter).
(u) The methane and dust control systems at underground dumps,
crushers, transfer points, and haulageways.
(v) Areas in trolley haulage entries where the air velocity will be
greater than 250 feet per minute and the velocity in these areas (see
Sec. 75.327(b)).
(w) Locations where entries will be advanced less than 20 feet from
the inby rib without a crosscut being provided where a line brattice
will be required. (see Sec. 75.333(g)).
(x) A description of the bleeder system to be used, including its
design (see Sec. 75.334).
(y) The means for determining the effectiveness of bleeder systems
(see Sec. 75.334(c)(2)).
(z) The locations where measurements of methane and oxygen
concentrations and air quantities and tests to determine whether the
air is moving in the proper direction will be made to evaluate the
ventilation of nonpillared worked-out areas (see Sec. 75.364 (a)(1))
and the effectiveness of bleeder systems (see Sec. 75.364 (a)(2)(iii).
Alternative methods of evaluation of the effectiveness of bleeder
systems (Sec. 75.364 (a)(2)(iv)).
(aa) The means for adequately maintaining bleeder entries free of
obstructions such as roof falls and standing water (see
Sec. 75.334(c)(3)).
(bb) The location of ventilation devices such as regulators,
stoppings and bleeder connectors used to control air movement through
worked-out areas (see Sec. 75.334(c)(4)). The location and sequence of
construction of proposed seals for each worked-out area. (see
Sec. 75.334(e)).
(cc) In mines with a demonstrated history of spontaneous
combustion: a description of the measures that will be used to detect
methane, carbon monoxide, and oxygen concentration during and after
pillar recovery and in worked-out areas where no pillars have been
recovered (see Sec. 75.334(f)(1); and, the actions which will be taken
to protect miners from the hazards associated with spontaneous
combustion (see Sec. 75.334(f)(2). If a bleeder system will not be
used, the methods that will be used to control spontaneous combustion,
accumulations of methane-air mixtures, and other gases, dusts, and
fumes in the worked-out area (see Sec. 75.334(f)(3)).
(dd) The location of all horizontal degasification holes that are
longer than 1,000 feet and the location of all vertical degasification
holes.
(ee) If methane drainage systems are used, a detailed sketch of
each system, including a description of safety precautions used with
the systems.
(ff) A description of the methods and materials to be used to seal
worked-out areas if those methods or materials will be different from
those specified by Sec. 75.335(a)(1).
(gg) The alternative location for the additional sensing device if
the device will not be installed on the longwall shearing machine (see
Sec. 75.342(a)(2)).
(hh) The ambient level in parts per million of carbon monoxide, and
the method for determining the ambient level, in all areas where carbon
monoxide sensors are installed.
(ii) The distance that separation between the primary escapeway and
the belt or track haulage entries will be maintained if other than to
the first connecting crosscut outby the section loading point (see
Sec. 75.380(g)).
(jj) In anthracite mines, the dimensions of escapeways where the
pitch of the coal seam does not permit escapeways to be maintained 4
feet by 5 feet and the locations where these dimensions must be
maintained (see Sec. 75.381(c)(4)).
Sec. 75.372 Mine ventilation map.
(a)(1) At intervals not exceeding 12 months, the operator shall
submit to the district manager 3 copies of an up-to-date map of the
mine drawn to a scale of not less than 100 nor more than 500 feet to
the inch. A registered engineer or a registered surveyor shall certify
that the map is accurate.
(2) In addition to the informational requirements of this section
the map may also be used to depict and explain plan contents that are
required in Sec. 75.371. Information shown on the map to satisfy the
requirements of Sec. 75.371 shall be subject to approval by the
district manager.
(b) The map shall contain the following information:
(1) The mine name, company name, mine identification number, a
legend identifying the scale of the map and symbols used, and the name
of the individual responsible for the information on the map.
(2) All areas of the mine, including sealed and unsealed worked-out
areas.
(3) All known mine workings that are located in the same coalbed
within 1,000 feet of existing or projected workings. These workings may
be shown on a mine map with a scale other than that required by
paragraph (a) of this section, if the scale does not exceed 2,000 feet
to the inch and is specified on the map.
(4) The locations of all known mine workings underlying and
overlying the mine property and the distance between the mine workings.
(5) The locations of all known oil and gas wells and all known
drill holes that penetrate the coalbed being mined.
(6) The locations of all main mine fans, installed backup fans and
motors, and each fan's specifications, including size, type, model
number, manufacturer, operating pressure, motor horsepower, and
revolutions per minute.
(7) The locations of all surface mine openings and the direction
and quantity of air at each opening.
(8) The elevation at the top and bottom of each shaft and slope,
and shaft and slope dimensions, including depth and length.
(9) The direction of air flow in all underground areas of the mine.
(10) The locations of all active working sections and the four-
digit identification number for each mechanized mining unit (MMU).
(11) The location of all escapeways.
(12) The locations of all ventilation controls, including permanent
stoppings, overcasts, undercasts, regulators, seals, airlock doors,
haulageway doors and other doors, except temporary ventilation controls
on working sections.
(13) The direction and quantity of air--
(i) Entering and leaving each split;
(ii) In the last open crosscut of each set of entries and rooms;
and
[[Page 9843]]
(iii) At the intake end of each pillar line, including any longwall
or shortwall.
(14) Projections for at least 12 months of anticipated mine
development, proposed ventilation controls, proposed bleeder systems,
and the anticipated location of intake and return air courses, belt
entries, and escapeways.
(15) The locations of existing methane drainage systems.
(16) The locations of all atmospheric monitoring system sensors.
(17) Contour lines that pass through whole number elevations of the
coalbed being mined. These lines shall be spaced at 10-foot elevation
levels unless a wider spacing is permitted by the district manager.
(18) The location of proposed seals for each worked-out area.
(19) The entry height, velocity and direction of the air current at
or near the midpoint of each belt flight where the height and width of
the entry are representative of the belt haulage entry.
(20) The location and designation of air courses that have been
redesignated from intake to return for the purpose of ventilation of
structures, areas or installations that are required by this subpart D
to be ventilated to return air courses, and for ventilation of seals.
(c) The mine map required by Sec. 75.1200 may be used to satisfy
the requirements for the ventilation map, provided that all the
information required by this section is contained on the map.
Sec. 75.373 Reopening mines.
After a mine is abandoned or declared inactive, and before it is
reopened, mining operations shall not begin until MSHA has been
notified and has completed an inspection.
Sec. 75.380 Escapeways; bituminous and lignite mines.
(a) Except in situations addressed in Sec. 75.381, Sec. 75.385 and
Sec. 75.386, at least two separate and distinct travelable passageways
shall be designated as escapeways and shall meet the requirements of
this section.
(b) (1) Escapeways shall be provided from each working section, and
each area where mechanized mining equipment is being installed or
removed, continuous to the surface escape drift opening or continuous
to the escape shaft or slope facilities to the surface.
(2) During equipment installation, these escapeways shall begin at
the projected location for the section loading point. During equipment
removal, they shall begin at the location of the last loading point.
(c) The two separate and distinct escapeways required by this
section shall not end at a common shaft, slope, or drift opening,
except that multiple compartment shafts or slopes separated by walls
constructed of noncombustible material may be used as separate and
distinct passageways.
(d) Each escapeway shall be--
(1) Maintained in a safe condition to always assure passage of
anyone, including disabled persons;
(2) Clearly marked to show the route and direction of travel to the
surface;
(3) Maintained to at least a height of 5 feet from the mine floor
to the mine roof, excluding the thickness of any roof support, except
that the escapeways shall be maintained to at least the height of the
coalbed, excluding the thickness of any roof support, where the coalbed
is less than 5 feet. In areas of mines where escapeways pass through
doors, the height may be less than 5 feet, provided that sufficient
height is maintained to enable miners, including disabled persons, to
escape quickly in an emergency. In areas of mines developed before
November 16, 1992, where escapeways pass over or under overcasts or
undercasts, the height may be less than 5 feet provided that sufficient
height is maintained to enable miners, including disabled persons, to
escape quickly in an emergency. When there is a need to determine
whether sufficient height is provided, MSHA may require a stretcher
test where 4 persons carry a miner through the area in question on a
stretcher;
(4) Maintained at least 6 feet wide except--
(i) Where necessary supplemental roof support is installed, the
escapeway shall not be less than 4 feet wide; or
(ii) Where the route of travel passes through doors or other
permanent ventilation controls, the escapeway shall be at least 4 feet
wide to enable miners to escape quickly in an emergency, or
(iii) Where the alternate escapeway passes through doors or other
permanent ventilation controls or where supplemental roof support is
required and sufficient width is maintained to enable miners, including
disabled persons, to escape quickly in an emergency. When there is a
need to determine whether sufficient width is provided, MSHA may
require a stretcher test where 4 persons carry a miner through the area
in question on a stretcher, or
(iv) Where mobile equipment near working sections, and other
equipment essential to the ongoing operation of longwall sections, is
necessary during normal mining operations, such as material cars
containing rock dust or roof control supplies, or is to be used for the
evacuation of miners off the section in the event of an emergency. In
any instance, escapeways shall be of sufficient width to enable miners,
including disabled persons, to escape quickly in an emergency. When
there is a need to determine whether sufficient width is provided, MSHA
may require a stretcher test where 4 persons carry a miner through the
area in question on a stretcher;
(5) Located to follow the most direct, safe and practical route to
the nearest mine opening suitable for the safe evacuation of miners;
and
(6) Provided with ladders, stairways, ramps, or similar facilities
where the escapeways cross over obstructions.
(e) Surface openings shall be adequately protected to prevent
surface fires, fumes, smoke, and flood water from entering the mine.
(f) Primary escapeway. (1) One escapeway that is ventilated with
intake air shall be designated as the primary escapeway.
(2) Paragraphs (f)(3) through (f)(7) of this section apply as
follows:
(i) To all areas of a primary escapeway developed on or after
November 16, 1992;
(ii) Effective as of March 11, 1997, to all areas of a primary
escapeway developed between March 30, 1970 and November 16, 1992; and
(iii) Effective as of March 11, 1997, to all areas of the primary
escapeway developed prior to March 30, 1970 where separation of the
belt and trolley haulage entries from the primary escapeway existed
prior to November 16, 1992.
(3) The following equipment is not permitted in the primary
escapeway:
(i) Unattended operating diesel equipment without an automatic fire
suppression system.
(ii) Mobile equipment hauling coal except for hauling coal
incidental to cleanup or maintenance of the primary escapeway.
(iii) Compressors, except--
(A) Compressors necessary to maintain the escapeway in safe,
travelable condition;
(B) Compressors that are components of equipment such as
locomotives and rock dusting machines; and
(C) Compressors of less than five horsepower.
(iv) Underground transformer stations, battery charging stations,
substations, and rectifiers except--
(A) Where necessary to maintain the escapeway in safe, travelable
condition; and
(B) Battery charging stations and rectifiers and power centers with
[[Page 9844]]
transformers that are either dry-type or contain nonflammable liquid,
provided they are located on or near a working section and are moved as
the section advances or retreats.
(v) Water pumps, except--
(A) Water pumps necessary to maintain the escapeway in safe,
travelable condition;
(B) Submersible pumps;
(C) Permissible pumps and associated permissible switchgear;
(D) Pumps located on or near a working section that are moved as
the section advances or retreats;
(E) Pumps installed in anthracite mines; and
(F) Small portable pumps.
(4) Mobile equipment operated in the primary escapeway, except for
continuous miners and as provided in paragraphs (f)(5), (f)(6), and
(f)(7) of this section, shall be equipped with a fire suppression
system installed according to Secs. 75.1107-3 through 75.1107-16 that
is--
(i) Manually operated and attended continuously by a person trained
in the systems function and use, or
(ii) A multipurpose dry chemical type capable of both automatic and
manual activation.
(5) Personnel carriers and small mobile equipment designed and used
only for carrying people and small hand tools may be operated in
primary escapeways if--
(i) The equipment is provided with a multipurpose dry chemical type
fire suppression system capable of both automatic and manual
activation, and the suppression system is suitable for the intended
application and is listed or approved by a nationally recognized
independent testing laboratory, or,
(ii) Battery powered and provided with two 10 pound multipurpose
dry chemical portable fire extinguishers.
(6) Notwithstanding the requirements of paragraph (f)(3)(i), mobile
equipment not provided with a fire suppression system may operate in
the primary escapeway if no one is inby except those persons directly
engaged in using or moving the equipment.
(7) Notwithstanding the requirements of paragraph (f)(3)(i), mobile
equipment designated and used only as emergency vehicles or ambulances,
may be operated in the primary escapeway without fire suppression
systems.
(g) Except where separation of belt and trolley haulage entries
from designated escapeways did not exist before November 15, 1992, the
primary escapeway shall be separated from belt and trolley haulage
entries for its entire length, to and including the first connecting
crosscut outby each loading point except when a greater or lesser
distance for this separation is specified and approved in the
ventilation plan and does not pose a hazard to miners.
(h) Alternate escapeway. One escapeway shall be designated as the
alternate escapeway. The alternate escapeway shall be separated from
the primary escapeway for its entire length, except that the alternate
and primary escapeways may be ventilated from a common intake air shaft
or slope opening.
(i) Mechanical escape facilities shall be provided and maintained
for--
(1) Each shaft that is part of a designated escapeway and is
greater than 50 feet in depth; and
(2) Each slope from the coal seam to the surface that is part of a
designated escapeway and is inclined more than 9 degrees from the
horizontal.
(j) Within 30 minutes after mine personnel on the surface have been
notified of an emergency requiring evacuation, mechanical escape
facilities provided under paragraph (i) of this section shall be
operational at the bottom of shaft and slope openings that are part of
escapeways.
(k) Except where automatically activated hoisting equipment is
used, the bottom of each shaft or slope opening that is part of a
designated escapeway shall be equipped with a means of signaling a
surface location where a person is always on duty when anyone is
underground. When the signal is activated or the evacuation of persons
underground is necessary, the person shall assure that mechanical
escape facilities are operational as required by paragraph (j) of this
section.
(l) (1) Stairways or mechanical escape facilities shall be
installed in shafts that are part of the designated escapeways and that
are 50 feet or less in depth, except ladders may be used in shafts that
are part of the designated escapeways and that are 5 feet or less in
depth.
(2) Stairways shall be constructed of concrete or metal, set on an
angle not to exceed 45 degrees from the horizontal, and equipped on the
open side with handrails. In addition, landing platforms that are at
least 2 feet by 4 feet shall be installed at intervals not to exceed 20
vertical feet on the stairways and equipped on the open side with
handrails.
(3) Ladders shall be constructed of metal, anchored securely, and
set on an angle not to exceed 60 degrees from the horizontal.
(m) A travelway designed to prevent slippage shall be provided in
slope and drift openings that are part of designated escapeways, unless
mechanical escape facilities are installed.
Sec. 75.381 Escapeways; anthracite mines.
(a) Except as provided in Secs. 75.385 and 75.386, at least two
separate and distinct travelable passageways shall be designated as
escapeways and shall meet the requirements of this section.
(b) Escapeways shall be provided from each working section
continuous to the surface.
(c) Each escapeway shall be--
(1) Maintained in a safe condition to always assure passage of
anyone, including disabled persons;
(2) Clearly marked to show the route of travel to the surface;
(3) Provided with ladders, stairways, ramps, or similar facilities
where the escapeways cross over obstructions; and
(4) Maintained at least 4 feet wide by 5 feet high. If the pitch or
thickness of the coal seam does not permit these dimensions to be
maintained other dimensions may be approved in the ventilation plan.
(d) Surface openings shall be adequately protected to prevent
surface fires, fumes, smoke, and flood water from entering the mine.
(e) Primary escapeway. One escapeway that shall be ventilated with
intake air shall be designated as the primary escapeway.
(f) Alternate escapeway. One escapeway that shall be designated as
the alternate escapeway shall be separated from the primary escapeway
for its entire length.
(g) Mechanical escape facilities shall be provided--
(1) For each shaft or slope opening that is part of a primary
escapeway; and
(2) For slopes that are part of escapeways, unless ladders are
installed.
(h) Within 30 minutes after mine personnel on the surface have been
notified of an emergency requiring evacuation, mechanical escape
facilities shall be operational at the bottom of each shaft and slope
opening that is part of an escapeway.
(i) Except where automatically activated hoisting equipment is
used, the bottom of each shaft or slope opening that is part of a
primary escapeway shall be equipped with a means of signaling a surface
location where a person is always on duty when anyone is underground.
When the signal is activated or the evacuation of personnel is
necessary, the person on duty shall assure that mechanical escape
facilities are operational as required by paragraph (h) of this
section.
[[Page 9845]]
Sec. 75.382 Mechanical escape facilities.
(a) Mechanical escape facilities shall be provided with overspeed,
overwind, and automatic stop controls.
(b) Every mechanical escape facility with a platform, cage, or
other device shall be equipped with brakes that can stop the fully
loaded platform, cage, or other device.
(c) Mechanical escape facilities, including automatic elevators,
shall be examined weekly. The weekly examination of this equipment may
be conducted at the same time as a daily examination required by
Sec. 75.1400-3.
(1) The weekly examination shall include an examination of the
headgear, connections, links and chains, overspeed and overwind
controls, automatic stop controls, and other facilities.
(2) At least once each week, the hoist shall be run through one
complete cycle of operation to determine that it is operating properly.
(d) A person trained to operate the mechanical escape facility
always shall be available while anyone is underground to provide the
mechanical escape facilities, if required, to the bottom of each shaft
and slope opening that is part of an escapeway within 30 minutes after
personnel on the surface have been notified of an emergency requiring
evacuation. However, no operator is required for automatically operated
cages, platforms, or elevators.
(e) Mechanical escape facilities shall have rated capacities
consistent with the loads handled.
(f) Manually-operated mechanical escape facilities shall be
equipped with indicators that accurately and reliably show the position
of the facility.
(g) Certification. The person making the examination as required by
paragraph (c) of this section shall certify by initials, date, and the
time that the examination was made. Certifications shall be made at or
near the facility examined.
Sec. 75.383 Escapeway maps and drills.
(a) A map shall be posted or readily accessible to all miners in
each working section, and in each area where mechanized mining
equipment is being installed or removed. The map shall show the
designated escapeways from the working section to the location where
miners must travel to satisfy the escapeway drill specified in
paragraph (b)(1) of this section. A map showing the main escapeways
shall be posted at a surface location of the mine where miners
congregate, such as at the mine bulletin board, bathhouse, or waiting
room. All maps shall be kept up to date, and any changes in route of
travel, locations of doors, or directions of airflow shall be shown on
the maps by the end of the shift on which the changes are made, and
affected miners shall be informed of the changes before entering the
underground areas of the mine. Miners underground on a shift when any
such change is made shall be immediately notified of the change.
(b) (1) At least once every 90 days, each miner, including miners
with working stations located between working sections and main
escapeways, shall participate in a practice escapeway drill. During
this drill, each miner shall travel the primary or alternate escapeway
from the miner's working section or area where mechanized mining
equipment is being installed or removed, to the area where the split of
air ventilating the working section intersects a main air course, or
2,000 feet outby the section loading point, whichever distance is
greater. Other miners shall participate in the escapeway drill by
traveling in the primary or alternate escapeway for a distance of 2,000
feet from their working station toward the nearest escape facility or
drift opening. An escapeway drill shall not be conducted in the same
escapeway as the immediately preceding drill.
(2) At least once every 6 weeks and for each shift, at least two
miners on each coal producing working section who work on that section,
accompanied by the section supervisor, shall participate in a practice
escape drill and shall travel the primary or alternate escapeway from
the location specified in paragraph (b)(1) of this section, to the
surface, to mechanical escape facilities, or to an underground entrance
to a shaft or slope to the surface. Systematic rotation of section
personnel shall be used so that all miners participate in this drill.
An escapeway drill shall not be conducted in the same escapeway as the
immediately preceding drill.
(3) At least once every 6 weeks, at least two miners on each
maintenance shift and a supervisor, shall participate in a practice
escape drill and shall travel the primary or alternate escapeway from
the location specified in paragraph (b)(1) of this section, to the
surface, to mechanical escape facilities, or to an underground entrance
to a shaft or slope to the surface. Systematic rotation of maintenance
personnel and working sections shall be used so that all miners
participate in this drill and the escapeways from all sections are
traveled. An escapeway drill shall not be conducted in the same
escapeway as the immediately preceding drill.
(4) Before or during practice escapeway drills, miners shall be
informed of the locations of fire doors, check curtains, changes in the
routes of travel, and plans for diverting smoke from escapeways.
(c) The practice escapeway drills may be used to satisfy the
evacuation specifications of the fire drills required by Sec. 75.1101-
23.
Sec. 75.384 Longwall and shortwall travelways.
(a) If longwall or shortwall mining systems are used and the two
designated escapeways required by Sec. 75.380 are located on the
headgate side of the longwall or shortwall, a travelway shall be
provided on the tailgate side of that longwall or shortwall. The
travelway shall be located to follow the most direct and safe practical
route to a designated escapeway.
(b) The route of travel shall be clearly marked.
(c) When a roof fall or other blockage occurs that prevents travel
in the travelway--
(1) Work shall cease on the longwall or shortwall face;
(2) Miners shall be withdrawn from face areas to a safe area outby
the section loading point; and
(3) MSHA shall be notified.
(d) Work may resume on the longwall or shortwall face after the
procedures set out in Secs. 75.215 and 75.222 are implemented.
Sec. 75.385 Opening new mines.
When new mines are opened, no more than 20 miners at a time shall
be allowed in any mine until a connection has been made between the
mine openings, and these connections shall be made as soon as possible.
Sec. 75.386 Final mining of pillars.
When only one mine opening is available due to final mining of
pillars, no more than 20 miners at a time shall be allowed in the mine,
and the distance between the mine opening and working face shall not
exceed 500 feet.
Sec. 75.388 Boreholes in advance of mining.
(a) Boreholes shall be drilled in each advancing working place when
the working place approaches--
(1) To within 50 feet of any area located in the mine as shown by
surveys that are certified by a registered engineer or registered
surveyor unless the area has been preshift examined;
(2) To within 200 feet of any area located in the mine not shown by
surveys that are certified by a registered engineer or registered
surveyor unless the area has been preshift examined; or
(3) To within 200 feet of any mine workings of an adjacent mine
located in
[[Page 9846]]
the same coalbed unless the mine workings have been preshift examined.
(b) Boreholes shall be drilled as follows:
(1) Into the working face, parallel to the rib, and within 3 feet
of each rib.
(2) Into the working face, parallel to the rib, and at intervals
across the face not to exceed 8 feet.
(3) At least 20 feet in depth in advance of the working face, and
always maintained to a distance of 10 feet in advance of the working
face.
(c) Boreholes shall be drilled in both ribs of advancing working
places described in paragraph (a) of this section unless an alternative
drilling plan is approved by the District Manager in accordance with
paragraph (g) of this section. These boreholes shall be drilled--
(1) At an angle of 45 degrees to the direction of advance;
(2) At least 20 feet in depth; and
(3) At intervals not to exceed 8 feet.
(d) When a borehole penetrates an area that cannot be examined, and
before mining continues, a certified person shall, if possible,
determine--
(1) The direction of airflow in the borehole;
(2) The pressure differential between the penetrated area and the
mine workings;
(3) The concentrations of methane, oxygen, carbon monoxide, and
carbon dioxide; and
(4) Whether water is impounded within the penetrated area.
(e) Unless action is taken to dewater or to ventilate penetrated
areas, boreholes shall be plugged with wooden plugs or similar devices
when--
(1) Tests conducted at the boreholes show that the atmosphere in
the penetrated area contains more than 1.0 percent methane, less than
19.5 percent oxygen, or harmful concentrations of carbon monoxide,
carbon dioxide or other explosive, harmful or noxious gases;
(2) Tests for methane, oxygen, carbon monoxide, and carbon dioxide
cannot be made because air from mine workings is flowing into the
penetrated area; or
(3) Water is discharging through the boreholes from the penetrated
area into the mine workings.
(f) If mining is to be conducted within 50 feet above or below an
inaccessible area of another mine, boreholes shall be drilled, as
necessary, according to a plan approved by the district manager.
(g) Alternative borehole patterns that provide the same protection
to miners as the pattern established by paragraphs (b) and (c) of this
section may be used under a plan approved by the district manager.
Sec. 75.389 Mining into inaccessible areas.
(a) (1) The operator shall develop and follow a plan for mining
into areas penetrated by boreholes drilled under Sec. 75.388.
(2) Mining shall not resume into any area penetrated by boreholes
until conditions in the penetrated area can be determined under
Sec. 75.388 and the plan for mining-through into the area has been
approved by the district manager.
(3) A copy of the procedures to be followed shall be posted near
the site of the mining-through operations and the operator shall
explain these procedures to all miners involved in the operations.
(b) The procedures specified in the plan shall include--
(1) The method of ventilation, ventilation controls, and the air
quantities and velocities in the affected working section and working
place;
(2) Dewatering procedures to be used if a penetrated area contains
a water accumulation; and
(3) The procedures and precautions to be followed during mining-
through operations.
(c) Except for routine mining-through operations that are part of a
retreat section ventilation system approved in accordance with
Sec. 75.371(f) and (x), the following provisions shall apply:
(1) Before and during mining-through operations, a certified person
shall perform air quality tests at intervals and at locations necessary
to protect the safety of the miners.
(2) During mining-through operations, only persons involved in
these operations shall be permitted in the mine; and
(3) After mining-through, a certified person shall determine that
the affected areas are safe before any persons enter the underground
areas of the mine.
[FR Doc. 96-5453 Filed 3-6-96; 11:23 am]
BILLING CODE 4510-43-P