2892 Federal Register / Vol. 60, No. 8 / Thursday, January 12, 1995 / Rules and Regulations

1Automatic Slack Adjusters for Heavy Vehicle

Brake Systems, February 1991, DOT HS 724, and

the National Transportation Safety Board Heavy

Vehicle Airbrake Performance, 1992, PB92–917003/

NTSB/SS–92/01

(v) The Highway Safety Act of 1966,

as amended, 23 U.S.C. 402(b)(1)(D).

Issued at Washington, DC this 5th day of

January 1995.

Federico Pen ̃ a,

Secretary of Transportation.

[FR Doc. 95–753 Filed 1–11–95; 8:45 am]

BILLING CODE 4910–62–U

National Highway Traffic Safety

Administration

49 CFR Part 571

[Docket No. 93–54, Notice 2]

RIN 2127–AE54

Federal Motor Vehicle Safety

Standards; Air Brake Systems; LongStroke Brake Chambers

AGENCY: National Highway Traffic

Safety Administration (NHTSA),

Department of Transportation.

ACTION: Final rule.

SUMMARY: Consistent with a

recommendation by the National

Transportation Safety Board and in

response to a petition for rulemaking

from the American Trucking

Associations (ATA), this final rule

amends the reservoir requirements in

Standard No. 121, Air Brake Systems,

for trucks, buses, and trailers equipped

with air brakes. The agency believes that

the amendments will improve the

braking efficiency of such vehicles and

reduce the number of brakes found to be

out of adjustment during inspections. It

will do this by removing a design

restriction that tends to discourage the

use of long-stroke brake chambers, a

technology with potentially significant

safety benefits.

DATES: Effective Date: The amendments

become effective on February 13, 1995.

Petitions for Reconsideration: Any

petitions for reconsideration of this rule

must be received by NHTSA no later

than February 13, 1995.

ADDRESSES: Petitions for reconsideration

of this rule should refer to Docket 93–

54; Notice 2 and should be submitted to:

Administrator, National Highway

Traffic Safety Administration, 400

Seventh Street SW., Washington, D.C.

20590.

FOR FURTHER INFORMATION CONTACT: Mr.

Richard Carter, Office of Vehicle Safety

Standards, National Highway Traffic

Safety Administration, 400 Seventh

Street SW., Washington, D.C. 20590

(202–366–5274).

SUPPLEMENTARY INFORMATION:

I. Background

Standard No. 121, Air Brake Systems,

specifies performance requirements

applicable to vehicles equipped with air

brakes. The Standard also requires airbraked vehicles to be equipped with

various types of equipment, including

an air compressor, reservoirs, and a

pressure gauge. (See section S5.1)

Standard No. 121 does not specify the

length of stroke of brake chambers, but

it establishes a ratio between the volume

of the service reservoirs and the volume

of the brake chambers. The reservoirs

store energy, in the form of air at high

pressure that is used to apply the

vehicle’s brakes. Without such

reservoirs, the vehicle’s air compressor

could not maintain adequate brake

system pressure during successive rapid

brake applications. The effect of this

ratio is that if the brake chamber stroke

is lengthened, thereby increasing its

volume, it may be necessary to enlarge

the service reservoirs.

With respect to trucks and buses,

Section S5.1.2.1 currently specifies that

The combined volume of all service

reservoirs and supply reservoirs shall be at

least 12 times the combined volume of all

service brake chambers at maximum travel of

pistons or diaphragms. However, the

reservoirs on the truck portion of an auto

transporter need not meet this requirement.

Similarly, with respect to trailers,

section S5.2.1.1 specifies

The total volume of each service reservoir

shall be at least eight times the combined

volume of all service brake chambers

serviced by that reservoir at the maximum

travel of the pistons or diaphragms of those

service brake chambers. However, the

reservoirs on a heavy hauler trailer and on

the trailer portion of an auto transporter need

not meet the requirements specified in

S5.2.1.1.

These provisions were intended to

ensure that a vehicle’s braking system

has sufficient compressed air to provide

adequate brake pressure after a number

of brake applications.

Brake chambers with longer strokes

are commonly known as ‘‘long-stroke’’

chambers, in reference to the longer

piston or pushrod travel that they

require. Reports 1 by NHTSA and the

National Transportation Safety Board

(NTSB) have indicated that long stroke

chambers can help improve brake

adjustment on heavy vehicles. However,

the reports also note that the reservoir

requirements in Standard No. 121

would necessitate much larger

reservoirs when long-stroke chambers

are used. Thus, while the current

requirements do not prohibit long-stroke

chambers, the requirements for reservoir

size significantly discourage their use.

II. Petition

On March 17, 1992, the American

Trucking Associations (ATA) petitioned

the agency to amend the reservoir

requirements in Standard No. 121 to

facilitate the installation of long-stroke

chambers. With respect to trucks, buses,

and trailers equipped with long-stroke

chambers, ATA recommended that the

combined volume of all the reservoirs

be based on the ‘‘rated volume’’ of the

service brake chambers, rather than on

the volume of the chambers at the

maximum travel of the piston. The

‘‘rated volume’’ of each brake chamber

would be determined pursuant to a table

of specified values according to the area

of the brake diaphragm and the length

of the stroke. In other words, under

ATA’s recommended amendment, if a

‘‘type 30’’ brake chamber (with a

diaphragm of approximately 30 square

inches) had a full stroke of at least 2.50

inches, then the rated volume of the

brake chamber would have to be at least

84 cubic inches. As a practical matter,

the use of long stroke chambers should

have a minimal effect on reservoir

capacity. For other types of brake

chambers not presented on the table, the

rated volume would be the volume of

the brake chamber at maximum travel of

the brake pistons or pushrods.

In support of its petition, ATA argued

that manufacturers would have to incur

unnecessary costs associated with

increasing the size of the reservoirs if

standard brake chambers were replaced

with long-stroke chambers. Along with

these additional costs, some vehicle

configurations would have to be

redesigned due to lack of adequate

locations with sufficient space to

accommodate large reservoirs. The lack

of space is especially significant with

short wheel base single unit trucks

equipped with extensive accessories

(e.g., power-take-off units (PTOs), tail

gate lifts, refrigeration units, larger

brakes) which compete for

undercarriage space.

III. Notice of Proposed Rulemaking

On August 2, 1993, NHTSA proposed

amending Standard No. 121’s reservoir

requirements for trucks, buses, and

trailers to facilitate the introduction of

long-stroke brake chambers. (58 FR

41078). Specifically, the agency

proposed that the method for

calculating air reservoir requirements

would be based on the ‘‘rated volume’’
Federal Register / Vol. 60, No. 8 / Thursday, January 12, 1995 / Rules and Regulations 2893

of the brake chambers rather than on the

volume of the brake chambers at the

maximum travel of the brake pistons or

push rods. The agency tentatively

agreed with the petitioner that the

proposed amendments would make it

easier for vehicle manufacturers to

install long-stroke brake chambers on

air-braked vehicles, because extremely

large reservoirs would no longer be

required. The agency stated that it

believed that long-stroke chambers

would help improve the braking

efficiency of vehicles, significantly

increase the reserve stroke, reduce the

number of brakes found to be out of

adjustment during inspections, and

reduce the incidence of dragging brakes.

NHTSA referenced the Safety Board

report, which concluded that ‘‘* * *

combining a properly installed and

maintained automatic slack adjuster

with a long-stroke chamber could

reduce the percentage of brakes at or

past the limit of adjustment from the 26

percent figure for the manual slack

adjusters on a regular stroke chamber to

the 4 percent figure for the automatic

adjusters installed on a long-stroke

chamber.’’

In the NPRM, NHTSA explained its

tentative determination that there would

be no safety problem with the amended

reservoir requirements. The agency

cited tests conducted at NHTSA’s

Vehicle Research and Test Center

(VRTC) that indicated that there is

sufficient reserve volume to stop an airbraked vehicle even under worst-case

conditions (i.e., the engine was stalled

so the compressor was not adding

replacement air to the system, the

vehicle was equipped with long-stroke

brake chambers and antilock brake

systems (ABS), and the vehicle was

stopped on a very low friction surface).

The VRTC tests further indicated that

while multiple combination vehicles

would experience an additional 10 psi

drop in air pressure because of the

compressor’s need to fill a greater

volume when the vehicle is equipped

with long-stroke chambers, there would

still be adequate air pressure to safely

stop a triple trailer combination vehicle

with ABS on a wet Jennite surface. The

rapid cycling produced by the ABS

under this condition places severe

demands on reservoir capacity and is

therefore a good measure of the reserve

pressure available from reservoirs

meeting the revised volumes proposed

in the NPRM. Notwithstanding its

tentative findings, NHTSA requested

comment about any potential safety

problems that might result from

amending the reservoir requirements to

facilitate the introduction of long-stroke

brake chambers.

IV. Comments to the NPRM

NHTSA received 15 comments in

response to the NPRM. Commenters

included vehicle manufacturers, brake

manufacturers, truck equipment

suppliers, ATA, the Heavy Duty Brake

Manufacturers Council (HDBMC) and

Advocates for Highway and Auto Safety

(Advocates).

Commenters addressed both the need

for the proposal and recommended

various modifications to the proposed

regulations.

Midland-Grau, Rockwell, Allied

Signal, HDBMC, Freightliner,

International Transquip Industries (ITI),

MGM Brakes, Ford, and ATA generally

believed that the proposal to facilitate

the use of long stroke brake chambers is

in the interest of safety. In contrast,

while WhiteGMC/Volvo, Haldex, Eaton,

and Advocates, agreed that long stroke

brake chambers could enhance safety,

they opposed the agency’s specific

proposal which they believed would

reduce the stringency of the reservoir

requirements and thus result in

detriment to safety.

V. Agency Determination

A. Overview

After reviewing the comments in light

of the available information, NHTSA

has decided to amend Standard No.

121’s reservoir requirements for trucks,

buses, and trailers to facilitate the

introduction of long-stroke brake

chambers. Specifically, under today’s

amendments, the method for calculating

air reservoir requirements is now based

on either the ‘‘rated volume’’ of the

brake chambers or the volume of the

brake chambers at the maximum travel

of the brake pistons or push rods,

whichever is less. As a result of these

amendments, it will be easier for vehicle

manufacturers to install long-stroke

brake chambers on air-braked vehicles,

because extremely large reservoirs will

no longer be required to meet the

reservoir requirements. The agency has

determined that long-stroke chambers

will help improve the braking efficiency

of vehicles, increase the reserve stroke,

reduce the number of brakes found to be

out of adjustment during inspections,

and reduce the incidence of dragging

brakes.

NHTSA has decided to modify the

proposed Table V ‘‘Brake Chamber

Rated Volumes’’ by specifying upper

limits to the stroke lengths for which

rated volumes may be used. As

explained below, the agency has

determined that specifying an upper

limit is necessary to preclude

manufacturers from extending stroke

lengths beyond the point at which

adequate air pressure reserves are

available to bring a vehicle to a

complete stop. Accordingly, the

amendment would not affect extremely

long stroke chambers, the use of which

could adversely affect air reservoir

capacity. Specifically, Table V has been

modified such that a vehicle

manufacturer can use the ‘‘rated

volume’’ rather than the actual brake

chamber volume, when determining

minimum reservoir volume, only when

the maximum strokes for long stroke

chambers are no more than 20 percent

longer than the nominal stroke for

standard stroke chambers. In addition,

the rated volumes have been increased

to reflect the largest volumes of standard

stroke air brake chambers that are

available.

B. Safety Consequences

In the NPRM, NHTSA considered the

safety implications of amending the

reservoir requirements to facilitate the

installation of long-stroke brake

chambers. The agency had tentatively

determined that relaxing the current

reservoir volume requirements would

not result in any safety problems.

Notwithstanding its tentative findings,

the agency requested comment about

potential safety problems that might

result from decreasing the stringency of

the reservoir requirements.

Midland-Grau, Rockwell, Allied

Signal, HDBMC, Freightliner, ITI, MGM

Brakes, Ford, and ATA generally

believed that the proposal to facilitate

the use of long stroke brake chambers

would have no corresponding safety

problems. HDBMC stated that long

stroke brake chambers will provide a

significant improvement in maintaining

a more reliable level of automatic brake

adjustment. Freightliner stated that long

stroke chambers will improve highway

safety by providing additional reserve

stroke at force levels that will maintain

brake performances under extreme

operating conditions. ATA stated that

the use of long stroke brake chambers

will decrease the number of vehicles

with defective brakes and provide for

more effective brakes, especially when

they are hot. Rockwell stated that the

current regulations unnecessarily

impede the adoption of long stroke

chambers and the potential benefits they

offer. It further stated that long stroke

chambers would keep the useful stroke

of a vehicle’s slack adjuster within the

acceptable stroke limits, reduce the

number of out-of adjustment vehicles,

and the number of incidents of dragging

brakes.
2894 Federal Register / Vol. 60, No. 8 / Thursday, January 12, 1995 / Rules and Regulations

2NHTSA’s Heavy-Duty Vehicle Research Program

Report No. 5: Pneumatic Timing. DOT HS 806 897,

December 1985.

3 Id.

In contrast, WhiteGMC/Volvo,

Haldex, Eaton, and Advocates believed

that the proposal would be detrimental

to safety, primarily because the

proposed amendments would make the

reservoir requirements less stringent.

WhiteGMC/Volvo stated that the

proposal promotes less reservoir volume

and extended application times.

Advocates had ‘‘misgivings about the

regulatory approach’’ in the NPRM

which it believed would significantly

reduce the total operating reserve

volume of the brake reservoirs, thereby

allowing manufacturers to install

undersized brake reservoirs. Haldex

stated that the proposal was ill advised

and premature because it would result

in a decrease in the reserve air volume.

Instead, it favored issuance of a

‘‘performance based standard.’’ Eaton

was concerned that the proposal was a

‘‘quick fix’’ that would degrade heavy

truck brake system performance.

After reviewing testing conducted at

VRTC, the comments, and other

available information, NHTSA has

determined that the amendments to

Standard No. 121’s reservoir

requirements will ensure the safe

braking of air-braked vehicles, since it

will not adversely affect their reservoir

capacity. Specifically, testing conducted

at VRTC indicate that today’s

amendments to Standard No. 121 will

not cause a significant reduction in a

brake system’s maintaining adequate

pressure even under adverse conditions,

affect its application and release times,

or contribute to a vehicle’s propensity to

jackknife.

With respect to a brake system’s air

reserves, VRTC and SAE testing indicate

that long stroke chambers perform

safely, even if the volume of the

reservoirs are not increased to reflect the

increased volume of the long stroke

chambers. In general, long stroke

chambers use no more air than standard

length brake chambers, if they are

properly adjusted. This testing

information has been placed in the

public docket under ‘‘Reservoir Pressure

Drop With ABS Cycling’’ and ‘‘SAE

J1911 Tractor and Trailer Tests.’’

Similarly, long stroke chambers in SAE

J1911 tests show the same air

consumption as a conventional brake

chamber, when properly adjusted.

The only time a long stroke chamber

will consume more air is when the

automatic adjuster is not functioning

correctly and the stroke is at the outer

limit of adjustment. To protect against

such situations, the agency has decided

to specify an upper limit for the

maximum stroke of brake chambers for

which a vehicle manufacturer can use

the ‘‘rated volume’’ in determining the

minimum reservoir volumes. The

agency has specified that the upper

limit be 20 percent above the nominal

stroke for a normal stroke brake

chamber. For instance, Type 9 brakes

will be allowed to have a stroke length

of between 1.75 and 2.10 inches. The

agency has rejected the upper limits

recommended by Midland-Grau which

in some cases would have increased the

stroke length up to 40 percent. The

agency believes that using ‘‘rated

volumes’’ for such long stroke chambers

might undermine the reservoir

requirements.

With respect to brake application

times, NHTSA has determined that long

stroke brake chambers typically do not

significantly affect brake apply and

release times. The effect of brake

adjustment level on timing is discussed

in ‘‘NHTSA Heavy-Duty Vehicle Brake

Research Program Report No. 5:

Pneumatic Timing.’’ DOT HS 806 897,

December 1985. The one exception is in

the highly unusual situation in which

all the automatic brake adjusters on a

vehicle fail and at the same time all of

the units operate at the outer limit of

adjustment or beyond. Even under this

highly unlikely condition, the apply

time would only increase by

approximately 0.040 second and the

release time by 0.024 second. Moreover,

standard stroke chambers would be

ineffectual in this situation. This

equates to about three additional feet of

stopping distance on the apply time and

two additional feet on the release time.2

Any such increases can be minimized,

since vehicle manufacturers can change

the apply and release times by

modifying the valving to adjust or

remove air flow restrictions. Similarly,

the vehicle manufacturers could remove

air flow restrictions to the glad hand

and pass the signal faster to the trailer.

With respect to jackknifes, NHTSA

disagrees with Eaton’s claim that

equipping vehicles with long stroke

chambers would increase the likelihood

of jackknifes. Jackknifes are caused by

wheel lockup due to hard brake

applications on wet roads or when

vehicles are empty or lightly loaded.

The presence or absence of long stroke

chambers will not affect the underlying

foundation brakes. Specifically, VRTC

studies 3 show that stroke lengths do not

affect brake timing. The agency further

notes that long stroke chambers improve

brake adjustment and the resulting

brake balance between tractors and

trailers, thereby improving a

combination vehicle’s directional

stability and control and decreasing the

likelihood of jackknifing.

C. Changes to Proposed Regulatory Text

Several commenters recommended

that the proposed wording of Table V

and S5.1.2.1 and S5.2.1.2 be modified to

provide greater flexibility to

manufacturers. For instance, ATA

requested that the words ‘‘on CAM

Brakes’’ be deleted from the title in

Table V so that it reads—‘‘Brake

Chamber Rated Volumes.’’ ATA also

requested that the words ‘‘brake

chamber’’ be changed to ‘‘brake

actuator’’ and that ‘‘actuator’’ be

inserted into Table V to clarify that the

‘‘type’’ is a brake actuator classification

and not a brake classification. Similarly,

ITI recommended that S5.1.2.1 and

S5.2.1.2 be revised to permit brake

chambers that were not of the sizes

specifically listed in Table V. Allied

recommended that the wording

‘‘maximum travel of pistons or push

rod’’ be replaced with ‘‘full stroke of

push rods.’’ It also recommended

‘‘defining chamber type as being the

nominal effective area of a piston or

diaphragm.’’

NHTSA has modified certain

provisions in the regulatory text

pursuant to the comments. For instance,

it has modified the title to Table V to

state ‘‘Brake Chamber Rated Volumes’’

instead of ‘‘Brake Chamber Rated

Volumes on Cam Brakes.’’ The agency

agrees with the commenters that

including the reference to cam brakes

was unnecessarily narrow and might

imply exclusion for use of other brake

types such as air disc, wedge, and airover-hydraulic. NHTSA has also

incorporated Allied Signal’s request for

the regulation to indicate that chamber

type is the nominal effective area of a

piston or diaphragm, by adding this

information to the top of column one in

Table V.

NHTSA decided not to modify other

provisions in the regulatory text,

notwithstanding recommendations by

commenters to the NPRM. For instance,

the agency decided not to adopt ATA’s

request to change the phrase ‘‘brake

chamber’’ to ‘‘brake actuator.’’

There are numerous references to

brake chamber throughout Standard No.

121, which are well understood by the

technical personnel who rely on the

requirements. ‘‘Brake actuator’’ may

explain what an air-brake chamber does

(i.e., that it actuates the brakes when it

fills with air); however, it adds nothing

to what is already understood.

Similarly, the agency decided not to

adopt Allied Signal’s request to

eliminate the term ‘‘piston.’’ While the
Federal Register / Vol. 60, No. 8 / Thursday, January 12, 1995 / Rules and Regulations 2895

4 ‘‘The Influence of Braking Strategy on Brake

Temperatures in Mountain Descents,’’ March 1992,

Federal Highway Administration Report DTFH61–

89–C–00106. Report available through the National

Technical Information Service. NTIS accession

number PB 93–137032.

commenter apparently believed that the

use of the additional word ‘‘piston’’

added nothing because every system has

a push rod, the agency nevertheless has

decided to include this term to clarify

that the necessary measurements of

stroke length can be measured at the

piston or the push rod. Accordingly, the

regulatory text retains this word.

D. Future Rulemaking

NHTSA notes that it is considering

rulemaking consistent with the draft

SAE Recommended Practice J1609X, Air

Reservoir Capacity Performance

Guide—Commercial Vehicles. The

purpose of such a rulemaking would be

to establish a performance requirement

addressing the minimum air storage

capacity for air-braked vehicles. If the

agency determined that such a

performance requirement were

appropriate, it would issue a proposal in

the Federal Register on which the

public could comment. A considerable

amount of testing needs to be completed

before a viable set of performance

requirements are established.

E. Miscellaneous Issues

Commenters raised a number of issues

that were not mentioned in the NPRM.

These include testing trucks on downhill grades, the consistency of the

amendment to the agency’s statutory

mandate, marking requirements, and the

rule’s effective date.

With respect to testing truck descents

on downhill grades, NHTSA disagrees

with comments by Advocates and

Haldex that the air reservoir

requirements should be based on such

testing and that such testing represents

worst-case situations. Braking on ice,

snow, and rain covered roads with low

coefficient of friction surfaces is more

severe than mountain grade braking.

The air pressure remaining after a

complete antilock cycling stop on ice or

wet Jennite is substantially less than

that remaining in the air brake system

at the bottom of a long mountain grade.

Moreover, VRTC studies clearly show

that there is sufficient air remaining in

the air brake system, after stopping on

low coefficient of friction surfaces or

mountain grades using either snubbing

or steady pressure. Similarly, testing

performed by the University of

Michigan Transportation Research

Institute (UMTRI) shows sufficient air

supply reserves on long down hill

grades to make a 60 psi full braking stop

at the bottom of the grade.4 Advocates

appears to misunderstand how downhill

braking affects an air brake system’s

reservoirs. Consumption and apply and

release times, which are important

concerns for long stroke chambers, are

not important concerns with downhill

braking. The major consideration in

downhill braking is overheated brakes

and brake fade caused by brakes that are

not in adjustment, since improperly

adjusted brakes must be applied for

longer periods of time. As a result, the

vehicle will have either no brakes or

very limited braking. The use of long

stroke brake chambers together with

automatic adjusters will reduce the

incidence of out-of-adjustment, and thus

not degrade the performance on

downhill braking.

Advocates stated that the petitioner’s

‘‘rated volume’’ approach to establish

the air reservoir volumes is equivalent

to the European type approval approach

for establishing compliance.

Accordingly, it believed that the

proposal was inconsistent with the

National Traffic and Motor Vehicle

Safety Act (now codified as chapter 301

of Title 49, United States Code). NHTSA

believes that Advocates has

misinterpreted both the proposal and

the law. Unlike European type approval,

the proposal is not for a single

manufacturer’s product. Rather, it

regulates all manufacturers’ brake

chambers of a specific type.

Accordingly, today’s requirements are

consistent with the law.

Rockwell and HDBMC recommended

that the agency require the

identification of long stroke chambers

through marking requirements.

Notwithstanding this request, NHTSA

notes that the agency cannot include a

marking requirement in this final rule

that it did not propose in the NPRM.

Nevertheless, the agency will monitor

the progress made by the Federal

Highway Administration which is

working with the SAE, Commercial

Vehicle Safety Alliance, and brake

equipment manufacturers to establish

an acceptable marking system that can

easily be identified under the difficult

visual conditions on the underside of air

braked vehicles. If NHTSA determines

that Federal marking requirements are

needed, then it would propose marking

requirements in a future rulemaking.

The same problem with inadequate

notice is relevant to Midland-Grau’s

recommendation to raise the minimum

governor cut-in pressure to 100 psi. The

agency may consider such a

requirement in a separate rulemaking,

depending on tests to be conducted at

VRTC.

In response to requests by Freightliner

and ATA for NHTSA to make the final

rule effective upon publication, the

agency notes that the Administrative

Procedure Act generally requires a

leadtime of at least 30 days, unless the

agency finds ‘‘good cause’’ to issue the

rule sooner. Since, NHTSA typically

makes a finding of good cause only in

emergency situations, the agency cannot

accommodate this request. The final

rule will take effect 30 days after its

publication in the Federal Register.

Rulemaking Analyses and Notices

Executive Order 12866 (Federal

Regulation) and DOT Regulatory

Policies and Procedures

NHTSA has considered the impact of

this rulemaking action under E.O.

12866, ‘‘Regulatory Planning and

Review’’ and the Department of

Transportation’s regulatory policies and

procedures. This rulemaking document

was not reviewed under E.O. 12866.

This action has been determined to be

not ‘‘significant’’ under the Department

of Transportation’s regulatory policies

and procedures. A full regulatory

evaluation is not required because the

rule will not impose any special

requirements on manufacturers. Instead,

the rule will facilitate the introduction

of a new brake design by removing a

design restriction. Therefore, the agency

believes that this rulemaking will not

result in significant additional costs or

cost savings.

Regulatory Flexibility Act

In accordance with the Regulatory

Flexibility Act, NHTSA has evaluated

the effects of this action on small

entities. Based upon this evaluation, I

certify that the amendments will not

have a significant economic impact on

a substantial number of small entities.

Vehicle and brake manufacturers

typically do not qualify as small

entities. As discussed above, the

agency’s assessment is that this

amendment will have no cost impact to

the industry. For these reasons, vehicle

manufacturers, small businesses, small

organizations, and small governmental

units which purchase motor vehicles

will not be affected by the requirements.

Accordingly, no regulatory flexibility

analysis has been prepared.

Executive Order 12612 (Federalism)

This action has been analyzed in

accordance with the principles and

criteria contained in Executive Order

12612, and it has been determined that

the rule will not have sufficient
2896 Federal Register / Vol. 60, No. 8 / Thursday, January 12, 1995 / Rules and Regulations

Federalism implications to warrant

preparation of a Federalism Assessment.

No State laws will be affected.

National Environmental Policy Act

Finally, the agency has considered the

environmental implications of this final

rule in accordance with the National

Environmental Policy Act of 1969 and

determined that the rule will not

significantly affect the human

environment.

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, 49

CFR part 571 is amended to read as

follows:

PART 571—FEDERAL MOTOR

VEHICLE SAFETY STANDARDS

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.

2. Section 571.121 is amended by

revising S5.1.2.1 and S5.2.1.1 to read as

follows:

§ 571.121 Standard No. 121; Air brake

systems.

* * * * *

S5.1.2.1 The combined volume of all

service reservoirs and supply reservoirs

shall be at least 12 times the combined

volume of all service brake chambers.

For each brake chamber type having a

full stroke at least as great as the first

number in Column 1 of Table V, but no

more than the second number in

Column 1 of Table V, the volume of

each brake chamber for purposes of

calculating the required combined

service and supply reservoir volume

shall be either that specified in Column

2 of Table V or the actual volume of the

brake chamber at maximum travel of the

brake piston or pushrod, whichever is

lower. The volume of a brake chamber

not listed in Table V is the volume of

the brake chamber at maximum travel of

the brake piston or pushrod. The

reservoirs of the truck portion of an auto

transporter need not meet this

requirement for reservoir volume.

* * * * *

S5.2.1.1 The total volume of each

service reservoir shall be at least eight

times the combined volume of all

service brake chambers serviced by that

reservoir. For each brake chamber type

having a full stroke at least as great as

the first number in Column 1 of Table

V, but no more than the second number

in column 1, the volume of each brake

chamber for purposes of calculating the

required total service reservoir volume

shall be either that number specified in

Column 2 of Table V or the actual

volume of the brake chamber at

maximum travel of the brake piston or

pushrod, whichever is lower. The

volume of a brake chamber not listed in

Table V is the volume of the brake

chamber at maximum travel of the brake

piston or pushrod. The reservoirs on a

heavy hauler trailer and the trailer

portion of an auto transporter need not

meet this requirement for reservoir

volume.

* * * * *

§ 571.121 [Amended]

3. Section 571.121 is amended to

include the following table to be placed

after Figure 3.

TABLE V.—BRAKE CHAMBER RATED

VOLUMES

Brake chamber type

(nominal area of piston or diaphragm in

square inches)

Column 1,

full stroke

(inches)

Column

2, rated

volume

(cubic

inches)

Type 9 ..................... 1.75/2.10 25

Type 12 ................... 1.75/2.10 30

Type 14 ................... 2.25/2.70 40

Type 16 ................... 2.25/2.70 50

Type 18 ................... 2.25/2.70 55

Type 20 ................... 2.25/2.70 60

Type 24 ................... 2.25/2.70 70

Type 30 ................... 2.50/3.20 95

Type 36 ................... 3.00/3.60 135

Issued on January 5, 1995.

Ricardo Martinez,

Administrator.

[FR Doc. 95–752 Filed 1–11–95; 8:45 am]

BILLING CODE 4910–59–P

49 CFR Part 572

[Docket No. 95–01, Notice 1]

RIN 2127–AF48

Anthropomorphic Test Dummy; SixYear Old Dummy

AGENCY: National Highway Traffic

Safety Administration (NHTSA),

Department of Transportation.

ACTION: Final rule; technical

amendment.

SUMMARY: This document makes a minor

correction to the thorax assembly and

test procedure in NHTSA’s regulation

for the six-year-old child dummy. This

document corrects inconsistencies

between the figure in the regulation that

illustrates the test set-up for calibrating

the dummy’s thorax and the regulatory

text that describes the calibration test

procedure. This action removes

potential sources of concern and

confusion for manufacturers and users

of the dummy about whether a

particular six-year-old child dummy

meets the specifications of NHTSA’s

regulation for the dummy (part 572,

subpart I).

EFFECTIVE DATE: The changes made in

this rule are effective January 12, 1995.

FOR FURTHER INFORMATION CONTACT: Mr.

Stan Backaitis, Office of Vehicle Safety

Standards, National Highway Traffic

Safety Administration, 400 Seventh

Street SW., Washington, DC 20590.

Telephone: (202) 366–4912.

SUPPLEMENTARY INFORMATION: On

November 14, 1991, NHTSA published

a rule that added specifications for a 6-

year-old child test dummy to NHTSA’s

set of regulations for ‘‘Anthropomorphic

Test Dummies’’ (49 CFR part 572). The

agency explained in the rule that the 6-

year-old child dummy would be used to

test child restraint systems for older

children. The dummy is instrumented

with accelerometers for measuring

accelerations in the head and thorax

during dynamic testing. The rule

adopted performance criteria as

calibration checks to assure the

repeatability and reproducibility of the

dummy’s dynamic performance. These

specifications for the dummy are set

forth in subpart I of 49 CFR part 572.

In February 1994, First Technology

Safety Systems, Inc. (First Technology),

a manufacturer of test dummies,

informed the agency that figure 41 in

subpart I appears to have two errors.

Figure 41 illustrates the test set-up for

calibrating the dummy’s thorax (figure

41, ‘‘thorax impact test set-up’’). Both

errors are due to inconsistencies

between figure 41 and the regulatory