[Federal Register Volume 60, Number 47 (Friday, March 10, 1995)]
[Rules and Regulations]
[Pages 13297-13305]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-5412]



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DEPARTMENT OF TRANSPORTATION
49 CFR Part 571

[Docket No. 93-07; Notice 3]
RIN 2127-AE21


Federal Motor Vehicle Safety Standards; Stopping Distance 
Requirements for Vehicles Equipped With Hydraulic Brake Systems

AGENCY: National Highway Traffic Safety Administration (NHTSA), 
Department of Transportation.

ACTION: Final rule.

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SUMMARY: This final rule establishes stopping distance performance 
requirements in Standard No. 105, Hydraulic Brake Systems, for trucks, 
[[Page 13298]] buses, and multipurpose passenger vehicles (MPVs) that 
have a gross vehicle weight ratings (GVWRs) over 10,000 pounds and that 
are equipped with hydraulic brake systems. The requirements specify the 
distances in which different types of medium and heavy vehicles must 
come to a complete stop from a speed of 60 mph on a high coefficient of 
friction surface. The requirements are designed to reduce the number 
and severity of crashes involving these vehicles.
    This notice is one part of the agency's comprehensive effort to 
improve the braking ability of medium and heavy vehicles. In another 
final rule published elsewhere in today's Federal Register, the agency 
is adopting identical stopping distance requirements for medium and 
heavy vehicles that are equipped with air brake systems. In a third 
final rule, that responds to the Intermodal Surface Transportation 
Efficiency Act (ISTEA) of 1991, the agency is requiring medium and 
heavy vehicles to be equipped with an antilock brake system (ABS) to 
improve the lateral stability and control of these vehicles during 
braking.

DATES: Effective Dates: The amendments become effective on March 1, 
1999.
    Petitions for Reconsideration: Any petitions for reconsideration of 
this rule must be received by NHTSA no later than April 10, 1995.

ADDRESSES: Petitions for reconsideration of this rule should refer to 
Docket 93-07; Notice 3 and should be submitted to: Administrator, 
National Highway Traffic Safety Administration, 400 Seventh Street SW., 
Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Mr. George Soodoo, Office of Vehicle 
Safety Standards, National Highway Traffic Safety Administration, 400 
Seventh Street SW., Washington, DC 20590 (202-366-5892).

SUPPLEMENTARY INFORMATION:
I. Background
    A. Brake Related Crashes
    B. Braking Devices
II. NHTSA Activities
    A. Regulatory History
    B. Agency Research
    C. Heavy Vehicle Safety Report to Congress
III. Agency Proposal
IV. Comments to the Proposal
V. Agency Decision
    A. Overview
    B. Stopping Distance Requirements
    C. First Effectiveness Test
    D. Second Effectiveness Test
    E. Leadtime
    F. Costs

I. Background

A. Brake Related Crashes

    Medium and heavy vehicles<SUP>1 are involved in thousands of motor 
vehicle crashes each year. One of the most important factors that 
contributes to these crashes is brake system performance. Crashes in 
which braking is a contributory factor can be further subdivided into 
(1) crashes due to brake failures or defective brakes, (2) runaways on 
downgrades, due to maladjusted or overheated brakes, (3) crashes in 
which vehicles are unable to stop in time, and (4) loss-of-control 
crashes due primarily to locked wheels during braking.

    \1\Hereafter, these vehicles which have a gross vehicle weight 
rating (GVWR) of 10,000 pounds or more are referred to as heavy 
vehicles.
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    This final rule amending Standard No. 105, Hydraulic Brake Systems, 
to establish stopping distance requirements for hydraulically braked 
vehicles,<SUP>2 and the companion final rule amending Standard No. 121, 
Air Brake Systems (49 CFR 571.121), to reinstate stopping distance 
requirements for air braked heavy vehicles, will reduce the severity of 
or prevent crashes attributable to a vehicle's inability to stop in 
time.<SUP>3 In these crashes, the heavy vehicle's brakes function, but 
do not stop the vehicle quickly enough to avoid a crash. One way to 
reduce the severity or number of such crashes is to improve heavy 
vehicle stopping performance by reducing the distance needed to stop a 
vehicle. Even if crashes of this type were not totally prevented, 
improvements in stopping distance performance reduce collision impact 
speeds, and thus reduce crash severity.

    \2\Hydraulic brake systems are used on most single unit vehicles 
with gross vehicle weight ratings (GVWRs) of 26,000 pounds or less 
and on many medium and heavy trucks and buses with GVWRs between 
26,000 pounds and 33,000 pounds. Hydraulic brakes are available on 
single unit vehicles with GVWRs up to 46,000 pounds, but are used to 
a lesser degree with such vehicles. Heavy vehicles not equipped with 
hydraulic brakes are equipped with air brake systems.
     <SUP>3Today's companion final rule to require heavy vehicles to 
be equipped with antilock brake systems (ABS) will prevent braking-
induced loss-of-control crashes.
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    The following estimates regarding heavy vehicle crashes are from 
NHTSA's 1992 General Estimates System (GES) which is based on data 
transcribed from a nationally representative sample of state police 
accident reports (PARs) and the Fatal Accident Reporting System (FARS). 
NHTSA estimates that in 1992 there were about 168,000 crashes involving 
heavy combination vehicles (excluding truck tractors when operating 
bobtail, i.e., without a trailer). These crashes resulted in about 
13,600 injuries and 387 fatalities to truck occupants and about 51,500 
injuries and 2452 fatalities to occupants of other involved vehicles. 
For bobtail truck tractors alone, the agency estimates that there were 
about 8,400 crashes resulting in about 1,200 injuries and 39 fatalities 
to truck occupants and about 2,600 injuries and 178 fatalities to 
occupants of other involved vehicles. For heavy single-unit trucks, the 
agency estimates that there were about 192,600 crashes resulting in 
about 15,700 injuries and 165 fatalities to truck occupants and about 
48,300 injuries and 891 fatalities to occupants of other involved 
vehicles. In addition, crashes involving heavy vehicles result in more 
expensive and severe property damage than crashes involving light 
vehicles.
    It is very difficult to quantify the number of crashes in which a 
vehicle's brakes are unable to stop the vehicle in time. NHTSA 
estimates that in 1992 there were about 18,000 crashes involving heavy 
combination vehicles (excluding bobtail truck tractors). These crashes 
resulted in about 1,800 injuries and 57 fatalities to truck occupants 
and about 8,400 injuries and 754 fatalities to occupants of other 
involved vehicles. For bobtail truck tractors alone, the agency 
estimates that there were about 260 crashes resulting in about 100 
injuries and 7 fatalities to truck occupants and about 240 injuries and 
48 fatalities to occupants of other involved vehicles. For heavy 
single-unit trucks, the agency estimates that there were about 30,100 
crashes resulting in about 4,200 injuries and 17 fatalities to truck 
occupants and about 15,000 injuries and 276 fatalities to occupants of 
other involved vehicles. The Final Regulatory Evaluation (FRE) provides 
greater detail about how today's final rules will reduce injuries and 
fatalities resulting from such crashes.
    The agency emphasizes that not all inability-to-stop-in-time 
crashes are preventable. Nevertheless, improvements to heavy vehicle 
brake systems should prevent or reduce the severity of a significant 
number of these crashes.

B. Brake Designs and Equipment

    In order to understand the discussion of braking in this preamble, 
it is necessary to be familiar with several devices employed in braking 
systems. As explained in greater detail in the companion final rules 
about stopping distances for air-braked vehicles and about lateral 
control and stability, manufacturers have developed several devices 
related to the braking of hydraulically-braked heavy vehicles, 
[[Page 13299]] including load proportioning valves (LPVs) and antilock 
brake systems (ABS). LPVs change the brake proportioning to the drive 
axle after mechanically sensing the vehicle's load, and ABSs 
automatically control the amount of braking pressure applied to a wheel 
so as to prevent wheel lockup, thus increasing stability and control in 
emergency stops. As explained in the companion notices, these devices 
can also reduce stopping distances.

II. NHTSA Activities

A. Regulatory History

    As initially promulgated, Standard No. 105, Hydraulic Brake Systems 
(49 CFR 571.105), set performance requirements for motor vehicles with 
hydraulic service brakes. (37 FR 17970, September 2, 1972.) The 1972 
rule required, among other things, that heavy vehicles stop from 60 mph 
within 245 feet when in the lightly loaded condition and within 553 
feet under partial failure conditions. Some petitions for 
reconsideration challenged the setting of stopping distance 
requirements for hydraulically-braked vehicles that were more stringent 
than those set for air-braked vehicles in Standard No. 121. While the 
initial stopping distance requirement of 245 feet in Standard No. 121 
was identical to Standard No. 105's requirement, Standard No. 121 was 
later revised to require stopping within 258 feet and then 293 feet.
    The requirements for air-braked vehicles were to become effective 
on September 1, 1973, and those for hydraulic-braked vehicles, on 
September 1, 1974. NHTSA extended the effective dates for the stopping 
distance requirements in Standard No. 105 and Standard No. 121. (37 FR 
3905, February 24, 1972; 38 FR 3047, February 1, 1973; 39 FR 17550, 
17563, May 17, 1974.) Prior to the final effective date for Standard 
No. 105, the amendments pertaining to heavy vehicles were withdrawn, so 
the requirements for heavy hydraulic-braked trucks and buses never went 
into effect. (40 FR 18411, April 28, 1975.) The agency concluded that 
the requirements that were being withdrawn could not be justified ``on 
the basis of the data available at this time.'' The agency noted that 
its decision to withdraw the amendment implementing requirements for 
vehicles other than passenger cars was based on uncertainty as to the 
achievable safety benefits relative to the costs of meeting those 
requirements, rather than on an explicit determination that the 
requirements were not justified. Notwithstanding this decision, the 
agency emphasized that ``truck braking is in many cases substantially 
poorer than passenger car braking, and that the generally longer 
stopping distances and the greater severity of truck accidents justify 
a safety standard for these vehicles.''
    There are two primary reasons for the substantial costs that would 
have been involved in meeting those requirements. The first reason was 
the level of stringency of the requirements: the stopping distance 
requirement from 60 mph was 246 feet, which was the original 
requirement implemented for air-braked vehicles in Standard No. 121 
that was later revised to 293 feet. The second reason relates to the 
state-of-the-art of hydraulic brake system technology in 1975 versus 
that of today. As discussed in detail in the Final Regulatory 
Evaluation (FRE), the requirements being implemented by this notice 
will not require any changes in the design or performance of 
hydraulically-braked heavy vehicles.
    Since its decision in 1975 to narrow Standard No. 105's 
applicability, NHTSA has issued several amendments extending its 
applicability to certain types of vehicles. In 1976, the agency 
extended the Standard's applicability to all school buses. (41 FR 2391, 
January 16, 1976.) In 1981, it extended the standard's applicability on 
a general basis (with some limitations) to trucks, all types of buses, 
and MPVs with a GVWR of 10,000 pounds or less. (46 FR 55, January 2, 
1981.) As for trucks, buses, and MPVs with a GVWR greater than 10,000 
pounds, the agency extended the requirements for braking with partial 
hydraulic system failures and power booster unit failures. However, the 
service and parking brake performance requirements, including those for 
stopping distances, have not been re-adopted for hydraulically-braked 
trucks and non-school buses with GVWRs over 10,000 pounds. The reader 
should refer to the February 1993 NPRMs and today's companion final 
rules for a detailed discussion of the regulatory history.
    These requirements have received a great deal of agency and 
judicial attention. (58 FR 11009, February 23, 1993.) Along with 
certain other provisions, the stopping distance requirements for air-
braked vehicles were invalidated by the United States Court of Appeals 
for the 9th Circuit in PACCAR v. NHTSA, 573 F.2d 632, (9th Cir. 1978) 
cert. denied, 439 U.S. 862 (1978).
    While PACCAR involved air-braked vehicles, it is relevant to 
hydraulically-braked vehicles as well. The stability and control final 
rule contains a detailed discussion about PACCAR and how the agency has 
responded to that decision. As mentioned earlier, the stopping distance 
requirements in this final rule are significantly longer than those 
that were rescinded in 1975.
    However, as also discussed earlier, the same stopping distance 
requirements that were implemented in 1975 for air-braked vehicles were 
later extended to levels that are close to those included in this 
notice. One significant difference between the original requirements in 
1975 for hydraulically braked, heavy vehicles and those contained in 
today's final rule is that the agency has decided to specify different 
stopping distances for different configurations of heavy vehicles. 
Today's requirements can further be distinguished from those 
invalidated in the 1970s, since manufacturers will not need to 
significantly redesign their brakes or use overly aggressive foundation 
brakes to comply with today's requirements.
    Even though the stopping distance requirements being specified in 
today's final rule are less stringent for some vehicle configurations 
than those invalidated by PACCAR for air-braked vehicles, the agency 
believes that the braking requirements in today's final rules, taken as 
a whole, significantly enhance the overall braking performance of 
hydraulically-braked vehicles given the agency's decision to require 
these vehicles to be equipped with ABS.

B. Agency Research

    As part of its review of heavy vehicle braking, NHTSA issued a 
report entitled ``NHTSA Heavy Duty Vehicle Brake Research Program 
Report No. 4--Stopping Capability of Hydraulically Braked Vehicles'' 
(DOT HS 806 860, October 1985). That report was based on a 
comprehensive testing of twelve hydraulically-braked vehicles ranging 
in weight from 14,800 to 46,000 pounds in both the empty and loaded 
conditions. The straight line stopping distance tests measured the 
shortest possible stop within a 12-foot-wide lane without locking up 
more than one wheel per axle or two wheels per tandem axle at speeds 
greater than 20 mph. At 60 mph, stopping distances ranged from 214 feet 
to 396 feet. Among other things, the agency found that the ability to 
stop in a short distance without loss of control is primarily a 
function of front/rear braking force distribution. Vehicles with brake 
force distributions closest to their dynamic weight distributions were 
the best performers. [[Page 13300]] 

C. Heavy Vehicle Safety Report to Congress

    In response to section 9107 of the Truck and Bus Regulatory Reform 
Act of 1988, the agency submitted a report to Congress entitled 
``Improved Brake Systems for Commercial Vehicles.'' (DOT HS 807 706, 
April 1991)<SUP>4 While the report focuses on air brakes systems, much 
of the information is relevant to hydraulically-braked heavy vehicles. 
After discussing crash data concerning heavy vehicle brake systems, the 
report explained factors related to braking effectiveness and stability 
and control during braking. The report mentioned that stopping 
distances and vehicle stability could be improved by equipping heavy 
vehicles with LPVs and ABS.

    \4\The report may be examined at the agency's Technical 
Reference Office, room 5108, at no charge. It is available from the 
National Technical Information Service (NTIS), Springfield, VA 22161 
for a small charge.
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III. Agency Proposal

    On February 23, 1993, NHTSA proposed to amend Standard No. 105 to 
establish different stopping distance requirements for different types 
of heavy vehicles equipped with hydraulic brake systems, when making 
stops from 60 mph on a high coefficient of friction surface. (58 FR 
11003.) The agency tentatively concluded that establishing the same 
stopping distance requirement for all heavy vehicles with fully 
operational service brakes would be inappropriate, since it would be 
too stringent for unloaded single unit trucks but not stringent enough 
for buses. The proposed stopping distances were based on the agency's 
analysis of the available data, especially the stopping distance 
results in the VRTC reports.
    NHTSA explained that its long-term objective is to upgrade the 
braking efficiency of heavy vehicles to enable them to make controlled, 
stable stops, under all loading and road surface conditions. The agency 
believed that the proposed requirements would reduce the disparity in 
stopping distance performance between heavy vehicles and passenger 
cars, while assuring that the requirements' costs are reasonable. The 
agency proposed stopping distance requirements for vehicles equipped 
with hydraulic brake systems consistent with the stopping distance 
requirements for air-braked heavy vehicles. These requirements would 
take effect two years after issuance of the final rule. The agency 
decided not to propose the first effectiveness test, which involves the 
preburnish condition. However, it proposed the second effectiveness 
test, where the vehicle is tested at its GVWR to assure full braking 
power, and the third effectiveness test where the vehicle is tested in 
the lightly loaded vehicle condition to assure reasonable brake 
balance.

IV. Comments on the Proposal

    NHTSA received 29 comments in response to the NPRM. Commenters 
included heavy vehicle manufacturers, brake manufacturers, safety 
advocacy groups, heavy vehicle users, industry trade associations, and 
other individuals. The American Automobile Manufacturers Association 
(AAMA) submitted joint comments on behalf of the eight major domestic 
manufacturers of heavy vehicles: Chrysler, Ford, Freightliner, General 
Motors (GM), Mack Trucks, Navistar, PACCAR, and Volvo-GM.
    The commenters generally supported the agency's decision to 
establish stopping distance requirements. However, they offered mixed 
views about the specific stopping distances being proposed. GM, 
Navistar, Heavy Duty Brake Manufacturers Council (HDBMC), and Rockwell 
WABCO stated that the proposed stopping distance requirements are 
appropriate. In contrast, the Insurance Institute for Highway Safety 
(IIHS), the Coalition for Consumer Health, and Advocates for Highway 
Safety (Advocates) believed that the required distances for trucks and 
buses should be shorter. Advocates stated that the proposal did little 
more than ``grandfather'' existing braking capabilities and therefore 
would not result in the best available braking performance for large 
trucks.
    Commenters also addressed specific issues raised in the NPRM, 
including the requirements' applicability to school buses, the need for 
the first and fourth effectiveness tests, the vehicle test speed, the 
test surface specification, the wheel lock up restrictions, the initial 
brake temperature, the failed system test, the vehicle loading, the 
parking brake test, the burnish procedures, and the implementation 
schedule for the requirements. More specific discussions of these 
comments, and the agency's responses to them, are set forth either 
below or in the stopping distance rule for Standard No. 121.\5\

    \5\The stopping distance rule for air-braked vehicles discusses 
the issues of the test surface, wheel lock restrictions, initial 
brake temperature, the failed system test, vehicle loading, the 
parking brake test, and burnish procedures.
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V. Agency Decision

A. Overview

    Based on the FARS and other crash data, test data from the agency's 
heavy vehicle brake research program, comments to the NPRM, and other 
available information, NHTSA has decided to amend Standard No. 105 to 
establish stopping distance performance requirements for heavy vehicles 
that are equipped with hydraulic brake systems. The requirements, which 
apply to 60 mph stops on a high coefficient of friction surface, 
specify different stopping distance requirements for three different 
types of heavy vehicle configurations: (1) loaded and unloaded buses, 
(2) loaded single unit trucks, and (3) empty single unit trucks. The 
requirements are designed to standardize the distance needed for all 
heavy vehicles to come to a complete stop, thereby reducing the number 
and severity of crashes.
    This notice is one part of the agency's comprehensive effort to 
improve the braking ability of heavy vehicles. In another final rule 
published elsewhere in today's Federal Register, the agency is adopting 
identical stopping distance requirements for comparable heavy vehicles 
that are equipped with air brake systems. The agency believes that it 
is appropriate to specify the same stopping distance requirements for 
similar vehicles. In a third final rule, the agency is responding to 
the Intermodal Surface Transportation Efficiency Act (ISTEA) of 1991 by 
requiring heavy vehicles to be equipped with an antilock brake system 
to improve the lateral stability and control of these vehicles during 
braking.

B. Stopping Distance Requirements

    Based on its testing at VRTC, NHTSA proposed different stopping 
distances for various categories of vehicles, as follows:

Loaded and Unloaded Buses
280 ft.
Loaded Single-Unit Trucks
310 ft.
Empty Single-Unit Trucks
335 ft.

    The agency reasoned that a single stopping distance requirement for 
all heavy vehicles with fully operational service brakes would be too 
stringent for unloaded single unit trucks, but not be stringent enough 
for buses. Based on the VRTC test results, the agency anticipated that 
manufacturers would not have to make changes to the hydraulic braking 
systems of their vehicles to comply with the proposed stopping distance 
requirements.
    AAMA and most other industry commenters agreed with the stopping 
distance values proposed for the various vehicle configurations. GM, 
Navistar, [[Page 13301]] Heavy Duty Brake Manufacturers Council 
(HDBMC), and Rockwell WABCO commented that they believed that the 
proposed stopping distance requirements are appropriate. ATA agreed 
with the proposal to specify different stopping distances for different 
types and loadings of vehicles. It also agreed with specifying the same 
stopping distances for the same types of air-braked and hydraulically-
braked vehicles under the same loading conditions.
    In contrast, other commenters stated that the proposed stopping 
distances were not sufficiently stringent. Advocates stated that the 
proposed stopping distances simply ratify braking distances currently 
achieved by manufacturers and do not seek to improve real-world braking 
performance. It stated that except for the 280-foot requirement for 
buses, the other proposed stopping distances are longer than the 293 
feet established before PACCAR. Similarly, IIHS stated that the 
proposals do not go far enough toward requiring the best available 
braking for heavy vehicles.
    Based on the public comments and other available information, 
especially the VRTC test results, NHTSA has decided to specify 
different stopping distances for three separate categories of vehicles, 
when tested at a speed of 60 mph on a surface with a PFC of 0.9, as 
follows:

Loaded and Unloaded Buses
280 ft.
Loaded Single-Unit Trucks
310 ft.
Unloaded Single-Unit Trucks
335 ft.

    NHTSA believes that these stopping distances, combined with the 
stability and control final rule, will ensure that heavy vehicles make 
short stable stops within a reasonable distance. The agency further 
notes that the companion notice to require heavy vehicles to be 
equipped with antilock brake systems will also help to improve the 
braking performance of those vehicles enough to enable them to comply 
with the stopping distance requirements.

C. First Effectiveness Test

    The first effectiveness test in Standard No. 105, which is commonly 
known as the ``preburnish test,'' measures brake performance very early 
in a vehicle's life. School buses are the only heavy vehicle type 
currently subject to the first effectiveness test (and to Standard No. 
105's other stopping distance requirements.)
    In the NPRM, NHTSA did not propose applying the preburnish test to 
other heavy vehicles. The agency stated that the first effectiveness 
test would continue to apply to school buses, since it did not want to 
modify the Standard's current requirements. The agency reasoned that 
subjecting school buses (but not other heavy vehicles) to the first 
effectiveness test was appropriate given the provisions in the vehicle 
safety law pertaining to school buses (codified as 49 U.S.C. 301), and 
the ``stop-and-go'' duty cycle of school buses. The agency requested 
comment on whether to apply the first effectiveness test to heavy 
vehicles in general and whether to retain the test for school buses.
    AAMA, AlliedSignal, and HDBMC stated that heavy vehicles, including 
school buses, should not be subject to the first effectiveness test and 
the 30-mph second effectiveness test. AlliedSignal commented that 
excluding hydraulically braked school buses from the first 
effectiveness test would be consistent with the agency's intent for 
consistency between hydraulically braked and air-braked vehicles. 
AlliedSignal also stated that the intended usage of non-school buses 
and school buses is nearly identical, and that chassis components are 
nearly identical. AAMA commented that school buses and non-school buses 
should have standardized braking requirements. AAMA disagreed with the 
agency's statement that the school bus provisions of the law have a 
bearing on the need for a first effectiveness or 30-mph second 
effectiveness requirements for school buses. Straight-Stop and Arent 
Fox recommended that transit buses and school buses be tested at speeds 
typical of their normal use such as 20 to 30 mph. Chrysler agreed with 
the agency's proposal not to apply the first effectiveness test to 
heavy vehicles, except for school buses.
    Advocates requested that the agency apply the first effectiveness 
test to all hydraulic braked vehicles, not just school buses. It 
claimed that the new non-asbestos linings tend to swell early in the 
service lives of new brakes. As a result, it believed that the stopping 
distance would be degraded during this period, a phenomenon that would 
be detrimental to safety. Advocates argued that the agency cannot 
arbitrarily dismiss the first effectiveness test with an assertion that 
it is not aware of any ``green brake'' crashes.
    After reviewing the comments and other available information, NHTSA 
has decided not to apply the preburnish test to all heavy vehicles 
equipped with hydraulic brakes. It has also decided that the test 
should not apply to school buses. As explained in the NPRM, NHTSA is 
not aware of any crashes involving hydraulically braked heavy vehicles 
caused by ``green'' brake linings. Therefore, the agency has determined 
that there is no need to apply the preburnish test to heavy vehicles. 
The agency notes that its decision not to apply the preburnish test to 
heavy vehicles results in the requirements in Standard No. 105 and 
Standard No. 121 being consistent for similar vehicles given the 
absence of a preburnish test in FMVSS No. 121 for air-braked school 
buses.\6\

    \6\The agency decided not to include a preburnish test in 
Standard No. 135, reasoning that few vehicles are driven any length 
of time in an unburnished condition.
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    With respect to non-asbestos linings, NHTSA agrees that there is a 
tendency for such linings to swell early in the life of the new brakes. 
However, the agency has already addressed this issue in greater detail 
in a NPRM on the brake adjustment procedure for brake burnish of heavy 
vehicles (56 FR 66395, December 23, 1991). The agency concluded that 
the swelling of the non-asbestos linings has no effect on their service 
life or on the service brake performance of the vehicle.

D. Second Effectiveness Test

    The second effectiveness test in Standard No. 105 assesses brake 
performance when a vehicle is in its fully loaded condition. In the 
NPRM, NHTSA proposed extending the second effectiveness test to 
hydraulically-braked heavy vehicles. The agency explained that this 
test replicates one of the most common loading conditions for heavy 
vehicles. The agency tentatively concluded that it would be in the 
interests of safety to establish stopping distance requirements for 
hydraulically-braked heavy vehicles in the fully loaded condition (at 
GVWR).
    NHTSA notes that, unlike the requirements in Standard No. 121 which 
specify 60-mph stops, the second effectiveness test includes 30-mph 
stops as well as 60-mph stops. The agency proposed applying the 30-mph 
test to school buses, since it is similar to their in-service stop-and-
go operation. Although there is no similar 30-mph road test for air-
braked school buses, the brake assemblies of these vehicles are 
required to be tested on a dynamometer under section S5.4 of Standard 
No. 121. These tests evaluate the capability of a brake assembly in a 
stop-and-go duty cycle. Section S5.4.2, Brake Power, requires that the 
brake be capable of making 10 consecutive decelerations from 50 mph to 
15 mph at an average deceleration rate of 9 feet per second. Therefore, 
the agency further believed that the 30-mph portion of the second 
effectiveness tests should be retained for school buses only, given 
their stop-and-go duty cycle. [[Page 13302]] 
    AlliedSignal was the sole commenter on the issue of the 30-mph 
stopping distances. It stated that its testing of a current system 
showed that the proposed requirement of 70 feet for the 30-mph second 
effectiveness test would be difficult to meet without major brake 
redesign. It therefore recommended that the requirement be increased to 
at least 78 feet if the agency decides not to exclude school buses from 
this test.
    NHTSA has decided to apply the test requirement to school buses 
with a stopping distance of 70 feet, as proposed. The agency notes that 
no vehicle manufacturer objected to the proposed stopping distance 
value. Further, NHTSA's test data (NHTSA Heavy-Duty Vehicle Brake 
Research Program Report No. 4--Stopping Capability of Hydraulically-
Braked Vehicles) show that 70 feet is a reasonable requirement from 30 
mph for the second effectiveness test.
    NHTSA acknowledges that some transit buses have stop-and-go duty 
cycles similar to school buses. However, such vehicles are typically 
equipped with air brake systems, and would therefore be required to 
have their brake assemblies dynamometer tested. The 30-mph second 
effectiveness test would not apply to these vehicles because they are 
not school buses.

E. Leadtime

    In the NPRM, NHTSA proposed that the stopping distance requirements 
become effective two years after the final rule's publication.
    AAMA supported the proposed effective date, provided that the 
agency incorporated its recommended modifications in the final rule. 
Rockwell recommended that the stopping distance requirements and the 
stability performance requirements be combined so that the effective 
dates for both rulemakings are concurrent. Several commenters to the 
stability and control NPRM, including AAMA, made the same suggestion. 
AAMA noted that since ABS can have a direct influence on achievable 
stopping distance, it is important to optimize brake system performance 
by taking both stopping distance and stability into account.
    On April 12, 1994, NHTSA published a supplemental notice of 
proposed rulemaking (59 FR 17326) that proposed the following 
implementation schedule for both the stopping distance and lateral 
stability and control requirements:

Truck tractors
2 years after final rule (1996)
Trailers
3 years after final rule (1997)
Air-braked single unit trucks and buses
3 years after final rule (1997)
Hydraulic-braked single unit trucks and buses
4 years after final rule (1998).

The agency reasoned that making the effective dates for the two 
rulemakings concurrent would facilitate a more orderly implementation 
process, avoid the need for manufacturers to redesign the brakes on 
individual vehicles twice, and reduce the development and compliance 
costs that manufacturers would face as a result of these regulations. 
NHTSA requested comments about the implementation schedule proposed in 
the supplemental notice.
    As the stability and control final rule discusses in detail in the 
section titled ``Implementation Schedule,'' NHTSA has decided to adopt 
an implementation schedule similar to the one proposed in the SNPRM. 
Specifically, hydraulically-braked heavy vehicles manufactured on or 
after March 1, 1999 will have to be equipped with ABS and comply with 
the high coefficient of friction stopping distance requirements. The 
agency has decided that these effective dates, which were widely 
supported by vehicle manufacturers, brake manufacturers, and safety 
advocacy groups, will provide for an efficient implementation of the 
heavy vehicle braking requirements.

F. Costs

    As indicated earlier, NHTSA does not anticipate the need for 
vehicle manufacturers to change the design of the foundation brake 
system of heavy, hydraulically braked vehicles in order to comply with 
the requirements of this final rule. The only costs associated with 
this rulemaking are those related to compliance testing costs. As 
detailed in the FRE, the agency estimates these costs to be $1.030 
million, or an average per-vehicle cost of $5.30.

Rulemaking Analyses and Notices

Executive Order 12866 and DOT Regulatory Policies and Procedures

    This rulemaking document was not reviewed under E.O. 12866. NHTSA 
has considered the impact of this rulemaking action under the 
Department of Transportation's regulatory policies and procedures. This 
action has been determined to be not ``significant'' under those 
policies and procedures.
    A FRE setting forth the agency's detailed analysis of the benefits 
and costs of this rulemaking (along with the other rules issued today) 
has been prepared and been placed in the docket. As mentioned above, 
the agency estimates that the costs attributable to these requirements 
are approximately $1.03 million for testing costs.
    Based on its analysis, the agency concludes that the requirements 
will improve safety by ensuring that all heavy vehicles are capable of 
stopping within a safe distance. The agency believes that implementing 
the stopping distance requirements for heavy vehicles will not result 
in significant costs since the braking performance of currently 
produced vehicles is adequate for these vehicles to comply with the 
reinstated requirements.
B. Regulatory Flexibility Act
    NHTSA has also considered the impacts of this notice under the 
Regulatory Flexibility Act. I hereby certify that this proposed rule 
will not have a significant economic impact on a substantial number of 
small entities. As mentioned above, most heavy vehicles will comply 
with the requirements without the need for significant changes. In 
addition, the agency is not aware of any manufacturer of heavy vehicles 
or hydraulic brake systems that is considered to be a small entity. 
There are no added costs associated with modifying a vehicle's brake 
system to comply with the requirements implemented by this final rule. 
The industry test cost per vehicle to assure compliance with the 
proposal is very small: $5.30. Accordingly, no regulatory flexibility 
analysis has been prepared.
C. Paperwork Reduction Act
    In accordance with the Paperwork Reduction Act of 1980 (P.L. 96-
511), there are no requirements for information collection associated 
with this proposed rule.
D. National Environmental Policy Act
    NHTSA has also analyzed this rule under the National Environmental 
Policy Act and determined that it will not have a significant impact on 
the human environment. No changes in existing production or disposal 
processes will result, except that there is a reduction resulting from 
the removal of the ALV. Nor should production and disposal processes 
have a significant adverse affect on the environment.
E. Executive Order 12612 (Federalism)
    NHTSA has analyzed this rule in accordance with the principles and 
criteria contained in E.O. 12612, and has determined that this rule 
will not have significant federalism implications to warrant the 
preparation of a Federalism Assessment.
[[Page 13303]]

F. Civil Justice Reform
    This final rule does not have any retroactive effect. Under 49 
U.S.C. 30103, whenever a Federal motor vehicle safety standard is in 
effect, a State may not adopt or maintain a safety standard applicable 
to the same aspect of performance which is not identical to the Federal 
standard, except to the extent that the State requirement imposes a 
higher level of performance and applies only to vehicles procured for 
the State's use. 49 U.S.C. 30161 sets forth a procedure for judicial 
review of final rules establishing, amending or revoking Federal motor 
vehicle safety standards. That section does not require submission of a 
petition for reconsideration or other administrative proceedings before 
parties may file suit in court.

List of Subjects in 49 CFR Part 571

    Imports, Motor vehicle safety, Motor vehicles, Rubber and rubber 
products, Tires.

    In consideration of the foregoing, the agency is amending Standard 
No. 105, Hydraulic Brake Systems, in Title 49 of the Code of Federal 
Regulations at Part 571 as follows:

PART 571--[AMENDED]

    1. The authority citation for Part 571 continues to read as 
follows:

    Authority: 49 U.S.C. 322, 30111, 30115, 30117, and 30166, 
delegation of authority at 49 CFR 1.50.


Sec. 571.105  [Amended]

    2. Section 571.105 is amended by adding the definition of ``wheel 
lockup'' in S4 and by revising Table II, S5.1.1, S5.1.1.2, S6, S6.9, 
and S6.10; and by adding S6.9.1, S6.9.2, S6.10.1 and S6.10.2 to read as 
follows:
* * * * *
    Wheel lockup means 100 percent wheel slip.
* * * * *

                                                                                                                
[[Page 13304]]                                                                                                  
                                                                                  Table II.--Stopping Distances                                                                                 
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                   Stopping distance in feet for tests indicated                                                
                                                 -----------------------------------------------------------------------------------------------------------------------------------------------
                                                      I--1st (preburnished) & 4th            II--2d effectiveness              III--3d (lightly loaded vehicles)         IV--Inoperative brake  
                                                  effectiveness; spike effectiveness ------------------------------------                effectiveness                   power and power assist 
       Vehicle test speed (miles per hour)                       check                                                   ---------------------------------------------   unit; partial failure  
                                                 ------------------------------------           (b) &                                                                 --------------------------
                                                                                        (a)      (c)      (d)      (e)      (a)      (b)      (c)      (d)      (e)              (b) &    (d) & 
                                                    (a)      (b)      (c)      (d)                                                                                       (a)      (c)      (e)  
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
30..............................................      <SUP>157    <SUP>1,265    <SUP>1,269                                                                                                                     
                                                                      (1st)                                                                                                                     
                                                                      <SUP>1,265     (4th                                                                                                            
                                                                        and                                                                                                                     
                                                                     spike)                                                                                                                     
                                                                        <SUP>172    <SUP>1,288      <SUP>154      <SUP>157    <SUP>1,278       70       51       57       65       84       70      114      130      170
35..............................................       74       83       91      132       70       74      106       96       67       74       83      114       96      155      176      225
40..............................................       96      108      119      173       91       96      138      124       87       96      108      149      124      202      229      288
45..............................................      121      137      150      218      115      121      175      158      110      121      137      189      158      257      291      358
50..............................................      150      169      185      264      142      150      216      195      135      150      169      233      195      317      359      435
55..............................................      181      204      224      326      172      181      261      236      163      181      204      281      236      383      433      530
60..............................................     <SUP>1216     <SUP>1242     <SUP>1267   <SUP>1,2388     <SUP>1204     <SUP>1216     <SUP>1310      280     <SUP>1194     <SUP>1216     <SUP>1242     <SUP>1335      280     <SUP>1456     <SUP>1517     <SUP>1613
80..............................................     <SUP>1405     <SUP>1459     <SUP>1510       NA     <SUP>1383       NA       NA       NA       NA       NA       NA       NA       NA       NA       NA       NA
95..............................................     <SUP>1607       NA       NA       NA       NA       NA       NA       NA       NA       NA       NA       NA       NA       NA       NA       NA
100.............................................     <SUP>1673       NA       NA       NA       NA       NA       NA       NA       NA       NA       NA       NA       NA       NA       NA      NA 
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
<SUP>1Distance for specified tests. <SUP>2Applicable to school buses only. NA=Not applicable.                                                                                                             
                                                                                                                                                                                                
Note: (a) Passenger cars; (b) vehicles other than passenger cars with GVWR of less than 8,000 lbs; (c) vehicles with GVWR of not less than 8,000 lbs and not more than 10,000 lbs; (d) vehicles 
  with GVWR greater than 10,000 lbs; (e) buses, including school buses, with GVWR greater than 10,000 lbs.                                                                                      


[[Page 13305]]

* * * * *
    S5.1.1  Stopping distance.
    (a) The service brakes shall be capable of stopping each vehicle 
with a GVWR of less than 8,000 pounds, and each school bus with a GVWR 
between 8,000 pounds and 10,000 pounds in four effectiveness tests 
within the distances and from the speeds specified in S5.1.1.1, 
S5.1.1.2, S5.1.1.3, and S5.1.1.4.
    (b) The service brakes shall be capable of stopping each vehicle 
with a GVWR of between 8,000 pounds and 10,000 pounds, other than a 
school bus, in three effectiveness tests within the distances and from 
the speeds specified in S5.1.1.1, S5.1.1.2, and S5.1.1.4.
    (c) The service brakes shall be capable of stopping each vehicle 
with a GVWR greater than 10,000 pounds in two effectiveness tests 
within the distances and from the speeds specified in S5.1.1.2 and 
S5.1.1.3.
* * * * *
    S5.1.1.2  In the second effectiveness test, each vehicle with a 
GVWR of 10,000 pounds or less and each school bus with a GVWR greater 
than 10,000 pounds shall be capable of stopping from 30 mph and 60 mph, 
and each vehicle with a GVWR greater than 10,000 pounds (other than a 
school bus) shall be capable of stopping from 60 mph, within the 
corresponding distances specified in Column II of Table II. If the 
speed attainable in 2 miles is not less than 84 mph, a passenger car or 
other vehicle with a GVWR of 10,000 pounds or less shall also be 
capable of stopping from 80 mph within the corresponding distances 
specified in Column II of Table II.
* * * * *
    S6  Test conditions. The performance requirements of S5 shall be 
met under the following conditions. Where a range of conditions is 
specified, the vehicle shall be capable of meeting the requirements at 
all points within the range. Compliance of vehicles manufactured in two 
or more stages may, at the option of the final-stage manufacturer, be 
demonstrated to comply with this standard by adherence to the 
instructions of the incomplete manufacturer provided with the vehicle 
in accordance with Sec. 568.4(a)(7)(ii) and Sec. 568.5 of title 49 of 
the Code of Federal Regulations.
* * * * *
    S6.9  Road Surface.
    S6.9.1  For vehicles with a GVWR of 10,000 pounds or less, road 
tests are conducted on a 12-foot-wide, level roadway, having a skid 
number of 81. Burnish stops are conducted on any surface. The parking 
brake test surface is clean, dry, smooth, Portland cement concrete.
    S6.9.2  For vehicles with a GVWR greater than 10,000 pounds, road 
tests are conducted on a 12-foot-wide, level roadway, having a peak 
friction coefficient of 0.9 when measured using an American Society for 
Testing and Materials (ASTM) E 1136 standard reference test tire, in 
accordance with ASTM Method E 1337-90, at a speed of 40 mph, without 
water delivery. Burnish stops are conducted on any surface. The parking 
brake test surface is clean, dry, smooth, Portland cement concrete.
* * * * *
    S6.10  Vehicle Position and Wheel Lockup Restrictions. The vehicle 
is aligned in the center of the roadway at the start of each brake 
application. Stops, other than spike stops, are made without any part 
of the vehicle leaving the roadway.
    S6.10.1  For vehicles with a GVWR of 10,000 pounds or less, stops 
are made with wheel lockup permitted only as follows:
    (a) At vehicle speeds above 10 mph, there may be controlled wheel 
lockup on an antilock-equipped axle, and lockup of not more than one 
wheel per vehicle, uncontrolled by an antilock system. (Dual wheels on 
one side of an axle are considered a single wheel.)
    (b) At vehicle speeds of 10 mph or less, any wheel may lock up for 
any duration.
    (c) Unlimited wheel lockup is allowed during spike stops (but not 
spike check stops), partial failure stops, and inoperative brake power 
or power assist unit stops.
    S6.10.2  For vehicles with a GVWR greater than 10,000 pounds, stops 
are made with wheel lockup permitted only as follows:
    (a) At vehicle speeds above 20 mph, any wheel on a nonsteerable 
axle other than the two rearmost nonliftable, nonsteerable axles may 
lock up for any duration. The wheels on the two rearmost nonliftable, 
nonsteerable axles may lock up according to (b).
    (b) At vehicle speeds above 20 mph, one wheel on any axle or two 
wheels on any tandem may lock up for any duration.
    (c) At vehicle speeds above 20 mph, any wheel not permitted to lock 
in (a) or (b) may lock up repeatedly, with each lockup occurring for a 
duration of one second or less.
    (d) At vehicle speeds of 20 mph or less, any wheel may lock up for 
any duration.
    (e) Unlimited wheel lockup is allowed during partial failure stops, 
and inoperative brake power or power assist stops.

    Issued on March 1, 1995.
Ricardo Martinez,
Administrator.
[FR Doc. 95-5412 Filed 3-7-95; 8:45 am]
BILLING CODE 4910-59-P