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Federal Motor Vehicle Safety Standards; Air Brake Systems

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Information about this document as published in the Federal Register.

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AGENCY:

National Highway Traffic Safety Administration (NHTSA, DOT.)

ACTION:

Final rule; technical amendment.

SUMMARY:

In a May 3, 1989 final rule, NHTSA changed the brake applications and release timing requirements of the Federal motor vehicle safety standard on air brake systems. The changes to these requirements resulted in the addition of a new schematic diagram of a trailer test rig, labeled as Figure 1, to the standard. A pre-existing trailer test rig schematic was re-labeled as Figure 1(a) and retained for use until the new brake application and release timing requirements and the new figure became effective May 3, 1991. We are now deleting the obsolete Figure (1)(a). A provision describing the pressure characteristics of the trailer test rig depicted in Figure 1(a) is also being deleted. We are also taking this opportunity to correct various minor errors and omissions in the standard.

DATES:

Effective Date: The amendment made by this final rule is effective June 27, 2002.

Petitions: Petitions for reconsideration must be received by July 12, 2002.

ADDRESSES:

Petitions for reconsideration should refer to the docket number of this rule and be submitted to: Administrator, National Highway Traffic Safety Administration, 400 Seventh Street, SW, Washington, DC 20590.

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FOR FURTHER INFORMATION CONTACT:

The following persons at the National Highway Traffic Safety Administration, 400 Seventh Street, SW, Washington, DC 20590:

For non-legal issues: Mr. Jeffrey Woods, 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) 366-8525, fax (202) 493-2739, electronic mail jwoods@nhtsa.dot.gov”.

For legal issues: Otto Matheke, Office of the Chief Counsel, NCC-20, telephone (202) 366-5253, facsimile (202) 366-3820, electronic mail omatheke@nhtsa.dot.gov”.

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SUPPLEMENTARY INFORMATION:

On May 3, 1989, we published a final rule (54 FR 18890) amending the brake applications and release timing requirements of Standard No. 121, Air brake systems. Under Standard 121, pneumatic brake systems must meet a number of performance requirements when subjected to testing that includes both on-road and dynamometer testing. One of the aspects of brake system performance measured by Standard No. 121 is how quickly brakes are applied once the brake pedal is depressed and how quickly the brakes release after the brake pedal is allowed to return to its original position. The 1989 final rule modified the existing application and release timing requirements and made several changes in how these application and release times are measured. One of the changes involved the test device, the trailer test rig, used in the timing tests. Due to this change, a schematic diagram of the test device to be used until the new timing requirements became effective on May 3, 1991, was re-labeled as Figure 1(a).

Mr. Robert J. Crail submitted a petition for rulemaking to NHTSA dated July 17, 2000 requesting that Figure 1(a) be deleted from Standard No. 121. Mr. Crail's petition correctly indicated that Figure 1(a) depicts a trailer test rig no longer used in the standard. The petition requested that Figure 1(a) be deleted because Figure 1 depicts the only trailer test rig now used in the standard. NHTSA granted the petition on April 6, 2001, indicating that it would review the issue to determine if further action would be appropriate.

The agency has reviewed this issue and concluded that Figure (1)(a), which is now obsolete, should be deleted. NHTSA also has reviewed Standard No. 121 for other errors and omissions and is correcting these matters in this technical amendment. The agency believes that none of these corrections will change the substantive requirements of the Standard or have any effect on manufacturers of vehicles subject to Standard No. 121.

As noted above, this technical amendment deletes Figure 1(a) depicting an obsolete trailer test rig. S6.1.13(b) which describes the pressure characteristics of the old trailer test rig depicted in Figure 1(a), is also being deleted. S6.1.13(a) which references the currently-used trailer test rig in Figure 1, is renumbered as S6.1.13.

NHTSA is also correcting other typographical errors and omissions. The last sentence of S5.4.1.1 currently states “after each stop, rotate the brake drum or disc until the temperature of the brake falls to between 125 °F. And 200 °F.” This sentence is being corrected by deleting the period after “125 °F” and removing the capitalization of the A in “and” to join the two sentences. As corrected, the last section of the sentence states “between 125 °F and 200 °F.” S6.1.2 states that “the inflation pressure is as specified by the vehicle manufacturer for the GVWR.” The word “tire” is now being inserted before the word “inflation.” Prior to this technical amendment, S6.1.8 included this sentence:

If the vehicle cannot attain a speed of 40 mph in 1 mph, 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.

We are now correcting S6.1.8 by replacing “1 mph” with “1 mile” so the sentence states “If the vehicle cannot attain a speed of 40 mph in 1 mile, continue * * *” Prior to the technical corrections set forth in this notice, S6.2.5 stated, in part, that “the rate of brake drum or disc rotation on a dynamometer or responding to the rate of rotation * * *” This phrase contained a typographical error as the words “or responding” were originally intended to be the single word “corresponding.” NHTSA now amends this section of S6.2.5 to state “the rate of brake drum or disc rotation on a dynamometer corresponding to the rate of rotation * * *”

Several errors in tables and figures are also being corrected. Table III specifies brake chamber pressures that relate to brake retardation forces in the dynamometer test requirements in S5.4.1 Brake retardation force. NHTSA is modifying Table III to remedy a typographical error in the heading for the first column of the table. The Start Printed Page 36820column heading incorrectly read “Column 1, Brake Retardation Force, GAWR.” The comma in between the word “Force” and the abbreviation “GAWR” is being modified to reflect that the numbers in Column 1 are the quotient of brake retardation force divided by gross axle weight rating. The column heading is being changed to “Brake Retardation Force/GAWR.”

A correction is also being made to the rated brake chamber volumes presented in Table V. In a final rule published in the Federal Register on July 11, 1996, (61 FR 36516) NHTSA revised the rated brake chamber volumes for long-stroke brake chambers in Table V. However, the revised brake volumes were never were put into Table V. Therefore, the correct values from the July 11, 1996, final rule are now being put into Table V.

NHTSA is also inserting a new section into the Standard. Standard No. 121 establishes brake performance requirements employing both dynamometer and road tests to measure braking force. Both tests require that brake temperatures be monitored before and during testing and each test must be performed when the brakes are in a certain temperature range. In order to assist those performing the dynamometer test, S6.2.4 provides guidance on the placement and mounting of temperature sensing devices on the brake shoes and contains a reference to a diagram contained in Figure 2. However, reference to Figure 2 and guidance on the installation of temperature sensing devices were omitted from the conditions for the road test contained in S6.1. In order to remedy this omission, S6.1 is amended to add a new paragraph, S6.1.16, outlining temperature sensor installation:

S6.1.16 Thermocouples. The brake temperature is measured by plug-type thermocouples installed in the approximate center of the facing length and width of the most heavily loaded shoe or disc pad, one per brake, as shown in Figure 2. A second thermocouple may be installed at the beginning of the test sequence if the lining wear is expected to reach a point causing the first thermocouple to contact the rubbing surface of a drum or rotor. The second thermocouple shall be installed at a depth of .080 inch and located within 1 inch circumferentially of the thermocouple installed at .040 inch depth. For centergrooved shoes or pads, thermocouples are installed within one-eighth of an inch to one-quarter of an inch of the groove and as close to the center as possible.

We find for good cause that notice and the opportunity to comment on these technical amendments are unnecessary and contrary to the public interest. As noted above, the agency believes that none of these corrections will change the substantive requirements of the Standard or have any effect on manufacturers of vehicles subject to Standard No. 121.

Rulemaking Analyses

A. Executive Order 12866 (Federal Regulation) and DOT Regulatory Policies and Procedures

This notice has not been reviewed under E.O. 12866. After considering the impacts of this rulemaking action, NHTSA has determined that the action is not significant within the meaning of the Department of Transportation regulatory policies and procedures. The final rule makes no substantive changes. The impacts are so minimal as not to warrant the preparation of a full regulatory evaluation.

B. Regulatory Flexibility Act

The agency has also considered the effects of this action in relation to the Regulatory Flexibility Act. For the reasons discussed above, I certify that this action would not have a significant economic impact upon “a substantial number of small entities.” The amendment is intended to assist potential applicants for temporary exemptions, including small businesses, to understand agency procedures so that, if a request for confidentiality is made, the documentation will be complete at the time the request is made. It is also designed to provide guidance as to arguments the agency considers relevant in making decisions upon exemption applications. Governmental jurisdictions will not be affected at all since they are generally neither importers nor purchasers of nonconforming imported motor vehicles.

C. Executive Order 12612 (Federalism)

The agency has analyzed this action in accordance with the principles and criteria contained in Executive Order 12612 “Federalism” and determined that the action does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

D. National Environmental Policy Act

NHTSA has analyzed this action for purposes of the National Environmental Policy Act and concludes that the action will not have a significant effect upon the environment because it is anticipated that the annual volume of motor vehicles produced or imported will not vary from that existing before promulgation of the rule.

E. Civil Justice Reform

This final rule will 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. A procedure is set forth in 49 U.S.C. 30161 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.

F. Unfunded Mandates Reform Act of 1995

The Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4) requires agencies to prepare a written assessment of the cost, benefits and other effects of proposed or final rules that include a Federal mandate likely to result in the expenditure by State, local, or tribal governments, in the aggregate, or by the private sector, of more than $100 million annually. Since this final rule will not have a $100 million effect, no Unfunded Mandates assessment has been prepared.

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List of Subjects in 49 CFR Part 571

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In consideration of the foregoing, NHTSA amends

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PART 571.121—[AMENDED]

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

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

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2. Amend Section 571.121 by revising S5.4.1.1, S6.1.8, S6.1.13, S6.2.5, Table III, Table V, removing figure 1(a), and adding S6.1.16 to read as follows:

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Air brake systems.
* * * * *

S5.4.1.1 After burnishing the brake pursuant to S6.2.6, retain the brake assembly on the inertia dynamometer. With an initial brake temperature between 125 °F. and 200 °F., conduct a stop from 50 m.p.h., maintaining brake chamber air pressure at a constant 20 psi. Measure the average torque exerted by the brake from the time the specified air pressure is reached until the brake stops and divide by the static loaded tire radius specified by the tire manufacturer to determine the retardation force. Repeat the procedure six times, increasing the brake chamber Start Printed Page 36821air pressure by 10 psi each time. After each stop, rotate the brake drum or disc until the temperature of the brake falls to between 125 °F. and 200 °F.

* * * * *

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.

* * * * *

S6.1.13 Trailer test rig.

The trailer test rig shown in Figure 1 is calibrated in accordance with the calibration curves shown in Figure 3. For the requirements of S5.3.3.1 and S5.3.4.1, the pressure in the trailer test rig reservoir is initially set at 100 psi for actuation tests and 95 psi for release tests.

* * * * *

S6.1.16 Thermocouples.

The brake temperature is measured by plug-type thermocouples installed in the approximate center of the facing length and width of the most heavily loaded shoe or disc pad, one per brake, as shown in Figure 2. A second thermocouple may be installed at the beginning of the test sequence if the lining wear is expected to reach a point causing the first thermocouple to contact the rubbing surface of a drum or rotor. The second thermocouple shall be installed at a depth of .080 inch and located within 1 inch circumferentially of the thermocouple installed at .040 inch depth. For centergrooved shoes or pads, thermocouples are installed within one-eighth of an inch to one-quarter of an inch of the groove and as close to the center as possible.

* * * * *

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.

* * * * *

Table III.—Brake Retardation Force

Column 1 brake retardation force/GAWRColumn 2 brake chamber pressure, PSI
0.0520
0.1230
0.1840
0.2550
0.3160
0.3770
0.4180
* * * * *

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 91.75/2.1025
Type 121.75/2.1030
Type 142.25/2.7040
Type 162.25/2.7046
Type 182.25/2.7050
Type 202.25/2.7054
Type 242.50/3.2067
Type 302.50/3.2089
Type 363.00/3.60135
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Dated: Issued: May 21, 2002.

Stephen R. Kratzke,

Associate Administrator for Safety Performance Standards.

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[FR Doc. 02-13221 Filed 5-24-02; 8:45 am]

BILLING CODE 4910-59-P