[Federal Register Volume 64, Number 22 (Wednesday, February 3, 1999)]
[Proposed Rules]
[Pages 5259-5264]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-2486]
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DEPARTMENT OF TRANSPORTATION
National Highway Traffic Safety Administration
49 CFR Part 571
[Docket No. NHTSA 99-5045]
RIN 2127-AH11
Federal Motor Vehicle Safety Standards: Air Brake Systems
AGENCY: National Highway Traffic Safety Administration (NHTSA),
Department of Transportation (DOT).
ACTION: Notice of proposed rulemaking; partial grant/partial denial of
petition for rulemaking.
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SUMMARY: Pursuant to the agency's partial grant of a petition for
rulemaking from the Truck Manufacturers Association, NHTSA proposes to
amend the air brake standard to correct an inconsistency between two
provisions concerning emergency brake stops, provide that single-unit
truck axles should not be overloaded, clarify the wheel-lock provisions
by adding a definition of ``tandem axle,'' and permit the use of roll
bars on vehicles undergoing brake testing.
NHTSA denies requests by the petitioner to amend the standard by
revising the braking test sequence, changing the provisions regarding
manual brake adjustments, changing the burnish procedure, specifying
application of the service brake prior to applying the parking brake,
and clarifying that emergency brake requirements for trucks and buses
do not become effective until March 1, 1998.
DATES: Comment closing date: Comments on this notice must be received
by NHTSA not later than April 5, 1999.
Proposed effective date: If adopted, the amendments proposed in
this notice would become effective 30 days after publication of the
final rule. Optional early compliance would be permitted on and after
the date of publication of a final rule in the Federal Register.
ADDRESSES: Comments should refer to the docket number for this rule
noted above and be submitted to: Docket Management Room, PL-401, 400
Seventh Street, SW, Washington, DC 20590. Docket Room hours are from 10
a.m. to 5 p.m., Monday through Friday.
FOR FURTHER INFORMATION CONTACT:
For technical issues: Mr. Joseph Scott, Safety Standards Engineer,
Office of Crash Avoidance Standards, Vehicle Dynamics Division,
National Highway Traffic Safety Administration, 400 Seventh Street, SW,
Washington, DC 20590; telephone (202) 366-2720, fax (202) 493-2739.
For legal issues: Mr. Walter Myers, Attorney-Advisor, Office of the
Chief Counsel, National Highway Traffic Safety Administration, 400
Seventh Street, SW, Washington, DC 20590; telephone (202) 366-2992, fax
(202) 366-3820.
SUPPLEMENTARY INFORMATION:
1. Background
Federal Motor Vehicle Safety Standard (Standard) No. 121, Air brake
systems, specifies performance and equipment requirements for trucks,
buses, and trailers equipped with air brake systems to ensure safe
braking performance under normal and emergency conditions.
Pursuant to the March 4, 1995 directive entitled ``Regulatory
Reinvention Initiative'' from the President to the heads of departments
and agencies of the Federal government, NHTSA reviewed its standards
and regulations to identify superseded or unneeded regulations as well
as to amend and update regulations as appropriate. One such regulation
identified by NHTSA for revising and upgrading was Standard No. 121.
Consequently, on May 31, 1996, NHTSA published a revision of Standard
No. 121 in the Federal Register to remove obsolete provisions and
update and reorganize the standard (61 FR 27288). The revision
substantially clarified and simplified the standard without changing
any of its substantive requirements. The effective date of this
revision was March 1, 1997. Optional early compliance with the revised
standard was permitted for vehicles manufactured prior to that date.
2. The Petition
The Truck Manufacturers Association (TMA) submitted a petition for
rulemaking to NHTSA dated January 6, 1997. The TMA is a trade
association
[[Page 5260]]
whose members include all the major U.S. manufacturers of medium and
heavy trucks, i.e., those trucks with a gross vehicle weight rating
(GVWR) greater than 8,845 kilograms (19,500 pounds). The petition was a
followup to TMA's comments submitted in connection with the rulemaking
action culminating with the final rule of May 31, 1996, discussed
above.
In its petition, the TMA stated that it, through a Society of
Automotive Engineers (SAE) task force, reviewed Standard No. 121 in
detail. As a result of that evaluation, SAE developed a recommended
practice, J1626, Braking, Stability, and Control Performance Test
Procedures for Air-Brake Equipped Trucks (REV APR96), to provide a
process for verifying vehicle compliance while minimizing test
variability. TMA commended NHTSA for its efforts to update and
reorganize Standard No. 121, but stated that some inconsistencies
remain. TMA stated that Standard No. 121 and SAE J1626 should be
aligned to improve test efficiency and decrease testing costs to the
industry with no detrimental impact on motor vehicle safety.
Accordingly, TMA suggested amending Standard No. 121 as follows:
a. Test sequence. Change the braking test sequence to perform the
unloaded straight line stops and then the loaded straight line stops
immediately following the braking-in-a-curve test. TMA asserted that
the standard currently allows the truck tractor braking-in-a-curve
control and stability tests to be performed loaded and unloaded
(bobtail) on a surface with 0.5 coefficient of friction. This
simplifies the logistics of moving vehicles from one test site to
another and limits the need to water the test track to only a single
time. TMA asserted, however, that the test sequence has little impact
on the test results as long as the burnish procedure is performed first
and final inspection follows all other required tests. The number of
times that a vehicle must be loaded and unloaded has a significant
impact on the time and effort to complete the sequence of tests. Thus,
the suggestion to conduct the unloaded straight line stops before the
loaded straight line stops would eliminate one loading/unloading
sequence, thereby simplifying the test sequence to that extent.
b. Brake adjustments. Adopt the following language of SAE J1626:
``(O)ther than during the burnish, brakes can be adjusted per the
vehicle manufacturer's procedure at any time.'' Although automatic
brake adjusters are required by the standard, TMA stated that some
automatic brake adjusters overadjust during Standard No. 121 testing,
but not in normal service. SAE J1626 recognizes this and would allow
brakes to be adjusted in accordance with the manufacturer's procedure
at any time to reduce brake performance variability.
c. Brake test and burnish procedure. Require that the entire brake
test procedure, including the burnish procedure, be conducted with the
transmission in neutral or with the clutch disengaged. Standard No. 121
specifies that tests are conducted with the vehicle's transmission in
neutral or with the clutch disengaged. This minimizes the effect of
engine and driveline drag on stopping distance test results and also
relieves the manufacturer of the burden of having to test every engine
and driveline package offered on a given chassis. TMA asserts that
engine and driveline drag can also affect burnish temperatures and the
conditioning that brake linings receive. Thus, TMA argues that
conducting the entire test sequence as well as the burnish procedure
with the transmission in neutral or the clutch disengaged would
eliminate variability in the burnish and the need to test with numerous
combinations of engines and drivelines that are offered with each
chassis.
d. Service brake application prior to parking brake application.
Permit a full service brake application prior to applying the parking
brakes, and clarify S5.6.3.1 to provide that it applies to the case in
which a single leakage failure occurs in the service brake system after
the parking brakes are applied. As a practical matter, when parking on
a hill, the vehicle operator first applies the service brakes to hold
the vehicle in place, then applies the parking brake before releasing
the service brakes. TMA stated that it is not clear whether S5.6
permits this procedure. It argues that Standard 105, Hydraulic and
electric brake systems, clearly permits a procedure in which the
service brake is applied prior to application of the parking brake.
Further, that standard permits reapplication of the service brake and
parking brake up to two additional times if the vehicle does not hold
on the grade. Thus, TMA requests that NHTSA clarify the parking brake
requirements of Standard No. 121 to make them more consistent with
those of Standard No. 105 in permitting a full application of the
service brakes prior to application of the parking brake, with
reservoirs at compressor cut-out pressure.
e. Clarify that emergency brake requirements for trucks and buses
do not become effective until March 1, 1998. Section S5.3 of the
standard specifies a schedule of effective dates for service brake
stopping distance requirements, which indicates that trucks and buses
have until March 1, 1998 to comply. Section S5.7 does not contain such
a schedule for emergency brake requirements. TMA considers that an
oversight on the agency's part that should be clarified.
f. Correction of inconsistency. TMA stated that the rulemaking
process confirmed that emergency brake stops for loaded tractors with
unbraked control trailers (item 4(b), Table I) are ``inappropriate.''
Subsection S5.7.3(b), however, retained the loaded tractor emergency
test that was in effect earlier. Therefore, TMA requested that NHTSA
delete S5.7.3(b) to correct the inconsistency.
g. Roll bar provision. Permit the use of a roll bar for any vehicle
conducting the brake test sequence, including the 60-mile-per-hour
(mph) straight-line stops and the 30-mph stops in a curve. TMA asserted
that the safety of drivers and technicians is a primary concern during
vehicle testing, and that use of a roll bar would protect them in the
event of a vehicle rollover. TMA pointed out that truck tractors are
permitted to be so equipped during the braking-in-a-curve stability and
control tests. It said that this protection is just as important for
short-wheelbase, high center of gravity trucks. A roll bar would ensure
the safety of the driver in all tests and would eliminate the need to
remove the roll bar after completing the braking-in-a-curve test
sequence.
h. Single-unit truck axles should not be overloaded. Paragraph
6.1.10.4 of the standard provides for loading the tractor control
trailer in such a manner as to avoid overloading the tractor's axles.
The axles of a single-unit truck should likewise not be overloaded to
achieve GVWR. Thus, the same provision should be incorporated into
paragraph S5.3.1.1.
i. Need for additional clarification of the wheel lock provisions.
TMA stated that the wheel lock provisions are not consistent with the
ABS provisions. Specifically, TMA pointed out that paragraph
S5.1.6.1(b) provides that ``the wheels of at least one rear axle'' of a
truck tractor must be equipped with an antilock brake system (ABS) that
directly controls the wheels on that axle. On the other hand, TMA
stated that subparagraph S5.3.1(a) places wheel lock restrictions on 2
rear axles, and that S5.3.1(b) allows one of those 2 axles to lock up
both of its wheels, but only if it is a tandem axle. TMA believes that
the wheel lock provisions were originally written for the stopping
[[Page 5261]]
distance NPRM, when it was not clear that ABS would be mandatory. When
the ABS and stopping distance proposals were combined for the final
rule, however, the conflict developed but went unnoticed until
recently.
By way of illustration of the suggested inconsistency between the
ABS and wheel lock requirements, TMA gives the example of a 3-axle
truck, bus or tractor. If the vehicle had 2 driven rear axles in
tandem, known as a 6x4 configuration, the wheels on both sides of one
rear axle might lock up during an entire stopping distance test.
Conversely, if one of the two rear axles were a nonliftable tag or
pusher axle, known as a 6x2 arrangement, then neither of the rear axles
could lock up on both its wheels. Thus, TMA argues that the 6x4 vehicle
needs ABS control on only one of its rear axles, while the 6x2 must
have ABS control on both rear axles.
TMA stated that drive axles are the most logical location on the
vehicle's rear for ABS, regardless of the number of axles trailing
behind. These axles have the greatest rolling inertia, are the heaviest
loaded, and are the only axles that can be used for traction control.
The wheel lockup provisions, however, discourage this approach on
vehicles with nonliftable tag axles. TMA therefore requested that the
wheel lockup provisions of S5.3.1(a) through (d) be rescinded, and that
S5.3.1 be redrafted to read:
S5.3.1 Stopping distance--trucks and buses. When stopped six times
* * * without any part of the vehicle leaving the roadway.
j. Typographical errors. TMA pointed out 2 typographical errors:
Paragraph S6.1.8, line 23, ``* * * in 1 mph* * *'' should
read ``* * * in 1 mile * * * ;'' and
Paragraph S6.2.5, line 2, ``* * * dynamometer or
responding * * *'' should read ``* * * dynamometer corresponding * *
*.''
3. Denials of Certain Requests by the Petitioner
a. Test sequence (see 2a above). TMA suggested allowing the tester
to ``perform the unloaded straight line stops and then the loaded
straight line stops immediately following the braking-in-a-curve
tests.'' The following table shows the current test sequence and TMA's
proposed sequence:
------------------------------------------------------------------------
Current sequence TMA's proposed sequence
------------------------------------------------------------------------
1. Burnish (GVWR)......................... 1. Burnish (GVWR)
2. a. Braking-in-Curve (GVWR); b. Braking- 2. a. Braking-in-Curve
in-Curve (LLVW). (GVWR); b. Braking-in-Curve
(LLVW)
3. Service Brake (GVWR); Emergency Brake 3. Service Brake (LLVW);
(GVWR). Emergency Brake (LLVW)
4. Parking Brake (GVWR)................... 4. Parking Brake (LLVW)
5. Service Brake (LLVW)................... 5. Service Brake (GVWR)
6. Emergency Brake (LLVW)................. 6. Emergency Brake (GVWR)
7. Parking Brake (LLVW)................... 7. Parking Brake (GVWR)
8. Final Inspection....................... 8. Final Inspection
------------------------------------------------------------------------
This request is denied because--
(1) The current GVWR/LLVW (lightly-loaded vehicle weight) is
consistent with the other tests in the overall test sequence.
(2) Flat-spotting of tires is minimized when GVWR tests are
conducted first. Since not all wheels are required to be ABS-controlled
and are therefore permitted to lock up, conducting the LLVW tests
first, particularly for the 60-mph stopping distance tests, could
result in severe flat-spotting of the tires on the non-ABS-controlled
axles. Subsequent vehicle test runs would be difficult with the tires
in that condition.
(3) The TMA proposal would eliminate one loading/unloading sequence
for truck tractors, but it would necessitate an additional unloading
sequence for single unit trucks and buses. The current test sequence
for single unit trucks and buses does not necessitate any load change
before the stopping distance tests are conducted since these vehicles
are not currently required to be tested to the braking-in-a-curve test
procedure. For these vehicles, TMA's proposed sequence would require
the next test after the burnish, which is conducted at GVWR, to be the
60-mph stopping distance test at LLVW. TMA did not address this issue.
(4) Not all vehicle manufacturers have the necessary test facility
to conduct the braking-in-a-curve test. Some manufacturers must
transfer their vehicles to a different site for testing. Therefore, if
TMA's test sequence were adopted, overall test efficiency would not
necessarily improve, particularly for these manufacturers.
b. Brake adjustments (see 2b above). The TMA request that the
agency permit brake adjustments at any time, other than during burnish,
is denied. Standard No. 121 requires air-braked vehicles to be equipped
with automatic brake adjusters. The potential for over-adjustment by
automatic brake adjusters during the series of full-treadle brake
applications required for braking-in-a-curve tests does exist. However,
the agency believes that it is important to specify when manual
adjustments are allowed since this enhances repeatability for
compliance testing.
The agency further believes that manual adjustment of the brakes
after each test sequence is inappropriate because it would be less
representative of real-world braking conditions. Standard No. 121
allows some brake adjustment during testing. For example, two manual
brake adjustments are allowed, one at the end of the braking-in-a-curve
test and the other at the end of the GVWR parking brake test. For
single unit trucks and buses, one manual brake adjustment is allowed at
the end of the GVWR parking brake test. NHTSA believes that current
limitations on the number of manual brake adjustments during the test
sequence sufficiently addresses the potential for brake over-adjustment
while preserving a well-defined test procedure.
c. Brake test and burnish procedure (see 2c above). The TMA request
that the entire brake test procedure, including the burnish procedure,
be conducted with the transmission in neutral or with the clutch
disengaged is denied.
Before a vehicle's brakes are tested for compliance with Standard
No. 121, the vehicle's brakes are burnished, also known as ``break-
in,'' by a series of brake applications called ``snubs''. The burnish
procedure is intended to simulate the break-in period that a vehicle's
brakes will receive when it is initially used on the public roads. The
current burnish procedures, which became effective in September, 1993
(53 FR 8190, March 14, 1988) specified that the brakes on heavy
vehicles be burnished without regard to the brake temperatures
generated during the burnish. The agency believes that this burnish
procedure is more realistic and representative of the break-in that the
vehicle brakes receive in actual service without favoring one brake
design over another.
The burnish procedure is required to be conducted with the vehicle
in gear. The agency believes that TMA's proposal to allow the vehicle's
brakes to be burnished with the clutch disengaged or the transmission
in neutral will result in a higher temperature burnish similar to the
old burnish procedure. The burnish procedure rulemaking rejected this
temperature-based approach to burnishing brake linings on heavy
vehicles. The current burnish procedure allows the brakes to reach
whatever temperatures they are designed to reach when driven in typical
stop-and-go driving. Therefore, any braking system
[[Page 5262]]
design will be conditioned fairly under this approach.
In addition, the procedure described in S7 of Standard No. 105,
when testing a vehicle in neutral, requires a four-part procedure that
is appropriate for a performance requirement, but would be very time-
consuming if applied to a 500-snub burnish procedure. The agency
believes that using this method in conducting the burnish procedure
would not be in the interest of testing efficiency that manufacturers
are striving to achieve.
TMA is also concerned about the burden on manufacturers to test
every engine and driveline package offered on a given chassis. The
agency notes that vehicle manufacturers are not required to and
currently do not test every combination of engine and drivetrain that
is offered on each vehicle. The legal requirement is that a
manufacturer exercise due care in assuring itself that its vehicle is
capable of meeting the performance requirements of applicable standards
when tested as prescribed in the standards.
d. Service brake application prior to parking brake application
(see 2d above). TMA's request that a full service brake application be
permitted prior to applying the parking brake is denied. The agency has
no test data comparing the grade holding ability of heavy truck air
brake systems using full service brake application prior to engaging
the parking brakes, nor did TMA supply such data.
The agency is concerned that, by allowing a full treadle
application prior to engaging the parking brake, colloquially referred
to as ``compounding,'' some vehicles may have reduced grade holding
ability. For example, in some applications, such as the construction
industry, trucks are often stopped on a grade in the unloaded condition
by a partial treadle application, after which the driver applies the
parking brake. In the lightly-loaded condition, a full treadle
application may not be needed to stop the vehicle on the grade. If the
vehicle were then loaded, however, it is possible that the parking
brake would not hold and the vehicle would roll away.
NHTSA is also concerned about the effects of full service brake
applications prior to engaging the parking brake on the durability of
foundation brake components such as brake chamber support brackets. For
a brief time when the air-applied service brakes and the mechanical
spring brakes both exert a braking force on the slack adjusters and
other foundation brake components, these additive forces can cause
damage to these brake components. Another concern is the effect on
foundation brake components when vehicles are parked with their brakes
at high temperatures. As those brake drums cool, they would impose
greater loads on the foundation brakes which could lead to permanent
deformation of some components.
The agency notes that this issue is an ongoing concern to the
industry in certifying vehicles to Standard No. 121. However, since
NHTSA has no test data with which to evaluate the feasibility of this
proposal and TMA did not provide any data to support its proposal, the
agency has decided to conduct vehicle research to evaluate the issue of
brake compounding. Since this research is not expected to be completed
until mid-1999, the agency denies this portion of the petition.
However, when our research has been completed and the test results
analyzed, it is the agency's intent to propose a clarification of the
test procedure or a revision of the regulatory language in S5.6.2 of
Standard No. 121.
e. Clarify that emergency brake requirements for trucks and buses
do not become effective until March 1, 1998 (see 2e above). This TMA
request is denied as being moot. Emergency brake requirements are now
in effect for all air braked vehicles as of March 1, 1998. Thus,
subsection S5.7 of Standard No. 121 will not now be amended to state
the effective dates of applicable requirements for the emergency brakes
of trucks and buses. The following table, however, is shown here for
information purposes:
Emergency Brake Requirements for Trucks and Buses: Effective Dates
(by vehicle and brake configuration)
------------------------------------------------------------------------
March 1:
1997 (Air).......................... New Truck Tractors.
1998 (Air).......................... New air-braked trailers &
single-unit trucks, buses.
1999 (Hydraulic).................... New single-unit trucks and
buses with hydraulic brakes.
------------------------------------------------------------------------
4. Grants of Certain Requests by Petitioner; Agency Proposals
a. Correction of inconsistency (see 2f above). TMA suggested that
emergency brake stops for loaded tractors with unbraked control
trailers are inappropriate. TMA is correct. The agency grants the
request and proposes to delete S5.7.3(b) since there is no longer a
requirement for emergency brake stops for truck tractors in the loaded
condition.
b. Roll bar provision (see 2g above). TMA suggested permitting the
use of a roll bar for any vehicle in this test sequence, including the
60-mph straight line stops and the 30-mph stops in a curve. The agency
grants the request and, in order to provide adequate protection for
test vehicle drivers in the event of a rollover during testing,
proposes to permit the use of roll bars in all test vehicles utilized
in the braking-in-a-curve tests and the straight line stopping distance
tests. Further, for the 60-mph straight line stops in the unloaded
condition, NHTSA proposes to include an allowance of up to 1,500 pounds
for driver, instrumentation, and roll bar. This allowance is not
applicable to tests in the loaded condition since the weight of these
items would be included as part of the load.
c. Single-unit truck axles should not be overloaded (see 2h above).
TMA suggested that paragraph S5.3.1.1 be amended to provide that
single-unit trucks should not be overloaded to achieve GVWR. The agency
grants the request and proposes to amend paragraph S5.3.1.1 to so
provide.
d. Need for additional clarification of the wheel lock provisions
(see 2i above). TMA suggested that the wheel lockup provisions be
clarified by rescinding the provisions of S5.3.1(a) through (d) (see
b(9) above). Although NHTSA does not agree with TMA's rationale for
deleting the wheel lock provision, the agency proposes to clarify any
misconceptions about the wheel lock provisions with respect to vehicles
with tandem axles.
The agency believes that the lack of a definition for ``tandem
axle'' is a primary cause for the misunderstanding of the wheel lock
restrictions of S5.3.1. The industry considers a tandem to be two or
more drive axles that are placed in a close arrangement one behind the
other, whereas NHTSA considers a tandem to be two or more axles (driven
or non-driven) placed in a close arrangement one behind the other.
Accordingly, NHTSA believes that for a 2-axle rear tandem with one
driven axle and one pusher axle, if ABS is on the driven axle and not
on the pusher axle, the two wheels on the pusher axle are permitted to
lock up for the duration of the stop, while the 2 ABS-controlled wheels
on the driven axle are allowed to lock up for only a duration of 1
second or less.
If, as TMA assumes, the two rear axles in the configuration of one
driven and one tag or pusher axle are not considered a tandem, TMA
would be correct that the lockup restriction of one wheel per axle
would apply and prevent both wheels on any one of the axles
[[Page 5263]]
from locking simultaneously. However, NHTSA believes that TMA is
incorrect in its statement that ``neither of the rear axles can have
lockup on both its wheels'' because NHTSA considers the 2-axle
configuration to be a tandem.
The agency believes that a definition of ``tandem axle'' is needed
in the standard to clarify the wheel lock provisions. That definition
would not include a requirement that all axles in a tandem be driven.
That should resolve the issue of having implied differences in the
stringency of the ABS requirements for heavy vehicles with 3 or more
axles based on the drivetrain configuration. Thus, a 6x2 single truck
(3-axle truck with one drive axle) could comply with the wheel lock
provisions using a 4-sensor/2-modulator antilock system since the two
rear axles would be defined as a tandem. That would allow any two
wheels on the tandem, that is either the tag or the pusher axle, to
lock for the duration of the test, if the axle is not ABS-controlled.
This definition has recently been included in Standard No. 105,
Hydraulic and electric brake systems, and NHTSA proposes adding it to
Standard No. 121 at this time.
e. Typographical errors (see 2j above). TMA is correct that 2
typographical errors appear in S6.1.8 and S6.2.5 respectively. NHTSA
will correct the 2 typographical errors identified by TMA, namely line
23 of the first paragraph of S6.1.8 which now reads ``1 mph'' will be
corrected to read ``1 mile.'' Similarly, line 2 of S6.2.5 that now
reads ``dynamometer or responding'' will be corrected to read
``dynamometer corresponding.''
5. Rulemaking Analyses and Notices
a. Executive Order 12866 and DOT Regulatory Policies and Procedures
This document has not been reviewed under Executive Order 12866,
Regulatory Planning and Review.
NHTSA has analyzed the impact of this rulemaking action and has
determined that it is not ``significant'' within the meaning of DOT's
regulatory policies and procedures. This action proposes to clarify and
amend certain provisions of Federal Motor Vehicle Safety Standard No.
121, Air brake systems, to permit the addition of a rollbar on test
vehicles when undergoing brake testing, clarify when wheel lockup is
permitted when brake testing, provide that single-unit truck axles
should not be overloaded when brake testing, and delete an obsolete
requirement. The amendments proposed herein would not impose any
additional costs on manufacturers of medium and heavy trucks. Although
the installation of roll bars on test vehicles would involve additional
costs, that provision is optional to manufacturers who may voluntarily
want to install them. Further, even if manufacturers chose to install
the bars on their test vehicles, the number of affected vehicles would
be very small. Thus, the agency estimates that implementation of the
proposals herein would not result in any increased costs to
manufacturers, distributors, or consumers. Accordingly, a full
regulatory evaluation was not prepared.
b. Regulatory Flexibility Act
NHTSA has considered the effects of this rulemaking action under
the Regulatory Flexibility Act, 5 U.S.C. 601, et seq. I hereby certify
that this notice of proposed rulemaking would not have a significant
impact on a substantial number of small entities.
The following is the agency's statement providing the factual basis
for the certification (5 U.S.C. 605(b)). The amendments proposed herein
would primarily affect manufacturers of medium and heavy trucks. The
Small Business Administration (SBA) regulation at 13 CFR part 121
defines a small business as a business entity which operates primarily
within the United States (13 CFR 121.105(a)).
SBA's size standards are organized according to Standard Industrial
Classification (SIC) codes. SIC code No. 3711, Motor Vehicles and
Passenger Car Bodies, prescribes a small business size standard of
1,000 or fewer employees. SIC code No. 3714, Motor Vehicle Part and
Accessories, prescribes a small business size standard of 750 or fewer
employees.
The amendments proposed in this rulemaking action would amend
Standard No. 121 to permit the addition of a rollbar on test vehicles
when undergoing brake testing, clarify when wheel lockup is permitted
when brake testing, provide that single-unit truck axles should not be
overloaded when brake testing, and delete an obsolete requirement.
These proposed amendments were requested by the trade organization that
represents the major manufacturers of medium and heavy trucks in the
U.S. The proposed amendments, if adopted, would not mandate any
increased costs or other burdens on truck manufacturers, most if not
all of which would not qualify as small businesses under SBA
guidelines. Neither would the proposed amendments result in any
increased costs for small businesses or consumers. Accordingly, there
would be no significant impact on small businesses, small
organizations, or small governmental units by these amendments. For
these reasons, the agency has not prepared a preliminary regulatory
flexibility analysis.
c. Executive Order No. 12612, Federalism
NHTSA has analyzed this rulemaking action in accordance with the
principles and criteria of E.O. 12612 and has determined that this rule
does not have sufficient federalism implications to warrant the
preparation of a Federalism Assessment.
d. National Environmental Policy Act
NHTSA has analyzed this rulemaking action for the purposes of the
National Environmental Policy Act and has determined that
implementation of this rulemaking action would not have any significant
impact on the quality of the human environment.
e. Paperwork Reduction Act
In accordance with the Paperwork Reduction Act of 1980, Pub. L. 96-
511, NHTSA states that there are no information collection requirements
associated with this rulemaking action.
f. Civil Justice Reform
The amendments proposed herein would not have any retroactive
effect. Under 49 U.S.C. 30103(b), whenever a Federal motor vehicle
safety standard is in effect, a state or political subdivision thereof
may prescribe or continue in effect a standard applicable to the same
aspect of performance of a motor vehicle only if the standard is
identical to the Federal standard. However, the United States
government, a state or political subdivision of a state may prescribe a
standard for a motor vehicle or motor vehicle equipment obtained for
its own use that imposes a higher performance requirement than that
required by the Federal standard. Section 30161 of Title 49, U.S. Code
sets forth a procedure for judicial review of final rules establishing,
amending or revoking Federal motor vehicle safety standards. A petition
for reconsideration or other administrative proceedings is not required
before parties may file suit in court.
6. Comments
Interested persons are invited to submit comments on the amendments
proposed herein. It is requested but not required that any such
comments be submitted in duplicate (original and 1 copy).
Comments must not exceed 15 pages in length (49 CFR 553.21). This
limitation is intended to encourage commenters to detail their primary
[[Page 5264]]
arguments in concise fashion. Necessary attachments, however, may be
appended to those comments without regard to the 15-page limit.
If a commenter wishes to submit certain information under a claim
of confidentiality, 3 copies of the complete submission, including the
purportedly confidential business information, should be submitted to
the Chief Counsel, NHTSA, at the street address noted above, and 1 copy
from which the purportedly confidential information has been deleted
should be submitted to Docket Management. A request for confidentiality
should be accompanied by a cover letter setting forth the information
called for in 49 CFR part 512, Confidential Business Information.
All comments received on or before the close of business on the
comment closing date indicated above for the proposal will be
considered, and will be available to the public for examination in the
docket at the above address both before and after the closing date. To
the extent possible, comments received after the closing date will be
considered. Comments received too late for consideration in regard to
the final rule will be considered as suggestions for further rulemaking
action. Comments on today's proposal will be available for public
inspection in the docket. NHTSA will continue to file relevant
information in the docket after the comment closing date, and it is
recommended that interested persons continue to monitor the docket for
new material.
Those persons desiring to be notified upon receipt of their
comments in the rule docket should enclose a self-addressed stamped
postcard in the envelope with their comments. Upon receiving the
comments, the docket supervisor will return the postcard by mail.
List of Subjects in 49 CFR Part 571
Imports, Motor vehicle safety, Motor vehicles, Rubber and rubber
products, and Tires.
In consideration of the foregoing, 49 CFR part 571 would be amended
as follows:
PART 571--FEDERAL MOTOR VEHICLE SAFETY STANDARDS
1. The authority citation for part 571 would continue to read as
follows:
Authority: 49 U.S.C. 322, 30111, 30115, 30117, and 30166;
delegation of authority at 49 CFR 1.50.
2. Section 571.121 would be amended in S4 by adding a definition of
``tandem axle'' in alphabetical order; by revising S5.3.1.1 (a) through
(c) and S5.7.3(b); by removing and reserving S5.7.3(c); and by revising
S6.1.8 and S6.2.5, to read as follows:
Sec. 571.121 Air brake systems.
* * * * *
S4. Definitions.
* * * * *
Tandem axle means a group or set of two or more axles placed in a
close arrangement, one behind the other, with the centerlines of
adjacent axles not more than 72 inches apart.
* * * * *
S5.3.1.1 * * *
(a) Loaded to its GVWR so that the load on each axle, measured at
the tire-ground interface, is most nearly proportional to the axles'
respective GAWRs, without exceeding the GAWR of any axle.
(b) In the truck tractor only configuration plus up to 500 lbs. or,
at the manufacturer's option, at its unloaded weight plus up to 500
lbs. (including driver and instrumentation) and plus not more than an
additional 1,000 lbs. for a roll bar structure on the vehicle, and
(c) At its unloaded vehicle weight (except for truck tractors) plus
up to 500 lbs. (including driver and instrumentation) or, at the
manufacturer's option, at its unloaded weight plus up to 500 lbs.
(including driver and instrumentation) plus not more than an additional
1,000 lbs. for a roll bar structure on the vehicle. If the speed
attainable in two miles is less than 60 mph, the vehicle shall stop
from a speed in Table II that is four to eight mph less than the speed
attainable in two miles.
* * * * *
S5.7.3 * * *
(b) Be capable of modulating the air in the supply or control line
to the trailer by means of the service brake control with a single
failure in the towing vehicle service brake system as specified in
S5.7.1.
(c) [Removed and reserved]
* * * * *
S6.1.8 For vehicles with parking brake systems not utilizing the
service brake friction elements, burnish the friction elements of such
systems prior to the parking brake test according to the manufacturer's
recommendations. For vehicles with parking brake systems utilizing the
service brake friction elements, burnish the brakes as follows: With
the transmission in the highest gear appropriate for a speed of 40 mph,
make 500 snubs between 40 mph and 20 mph at a deceleration rate of 10
f.p.s.p.s., or at the vehicle's maximum deceleration rate if less than
10 f.p.s.p.s. Except where an adjustment is specified, after each brake
application accelerate to 40 mph and maintain that speed until making
the next brake application at a point 1 mile from the initial point of
the previous brake application. If the vehicle cannot attain a speed of
40 mph in 1 mile, continue to accelerate until the vehicle reaches 40
mph or until the vehicle has traveled 1.5 miles from the initial point
of the previous brake application, whichever occurs first. Any
automatic pressure limiting valve is in use to limit pressure as
designed. The brakes may be adjusted up to three times during the
burnish procedure, at intervals specified by the vehicle manufacturer,
and may be adjusted at the conclusion of the burnishing, in accordance
with the vehicle manufacturer's recommendation.
* * * * *
S6.2.5 The rate of brake drum or disc rotation on a dynamometer
corresponding to the rate of rotation on a vehicle at a given speed is
calculated by assuming a tire radius equal to the static loaded radius
specified by the tire manufacturer.
* * * * *
Issued on January 26, 1999.
L. Robert Shelton,
Associate Administrator for Safety Performance Standards.
[FR Doc. 99-2486 Filed 2-2-99; 8:45 am]
BILLING CODE 4910-59-P
