ID: nht72-2.34

DATE: 04/13/72

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: Amerace - Esna Corporation

TITLE: FMVSS INTERPRETATION

TEXT: In your letter of February 4 to Mr. Schneider you discussed differences between SAS Standard J594d, March 1957, Reflex Reflectors, and its successor J594e, March 1970. You asked "whether relief can be granted in the unnecessary specular restriction appearing in Federal Motor Vehicle Safety Standard No. 108 because of its inclusion of J594d rather than J594e."

We have reviewed your letter and the administrator has determined that the issue you raised merits (Illegible Word) of rulemaking. I enclose a copy of a notice proposing an amendment to Standard No. 108 to substitute SAE J594e as the referenced requirement for reflex reflectors.

ID: nht72-2.35

DATE: 02/15/72

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: D. M. Schwentker, Esq. -- Busby, Rivkin, Sherman and Levy

TITLE: FMVSS INTERPRETATION

TEXT: In your letter of November 30, 1971, you ask if you may assume certain statements to be true. My reply lists your statements and discusses each separately.

"1. 571.5(a) applies to SAE Standards and Recommended Practices subreferenced by the SAE Standards and Recommended Practices referenced in the Federal Motor Vehicles Safety Standards contained in Part 571 as well as to the primary references.

The Initial Standards incorporate many SAE materials, probably due in large part to the statutory mandate that they be based upon existing standards. The intent of 571.5(a) appears to be to insure that those materials are legitimately incorporated into the Federal requirements, and that materials subject to change are in fact "frozen" as of a day certain, so that the Federal Standards are not subject to attack on grounds of vagueness. J575 is not directly "referred to" in Standard No. 106, but since its inclusion in Standard No. 108 is required to complete the structure of the Standard, I do not regard a direct reference as necessary to bring it within the ambit of 571.5(a). The SAE Standards that are part of Standard No. 108 "refer" to J575 and this is sufficient.

"2. [Materials] . . . 'in effect on the date of adoption of this Part . . . means [materials] . . . in effect on the date of publication in the Federal Register of the Federal Motor Vehicle Safety Standard or regulation in which they are referenced . . .'

The answer is obviously "yes" with reference to the Initial Standards; February 3, 1967, was both the "date of adoption of this Part" as well as "the date of publication in the Federal Register of the Federal Motor Vehicle Safety Standard or regulation in which they are referenced."

The answer is "no" with respect to Standards published after February 3, 1967. Section 571.5(a) says that materials subject to change incorporated in any Standard published subsequent to February 3, 1967, are those in effect on February 3, 1967, unless the reference to them provides otherwise.

"3. '. . . in effect . . .' with respect to SAE Standards and Recommended Practices means formally adopted by SAE although not necessarily printed in the SAE Handbook.

In the strict legal sense, an SAE Standard is never "in effect" since adherence to it is voluntary. One revision supersedes another but cannot be said legally to "revoke" it, ending its "effectivity."

SAE Standards do not have effective dates. They bear an identifying month and year indicating when the latest revision was approved by the appropriate SAE approval body. Thus, J575d, November 1966, means that the (Illegible Word) was approved by the SAE lighting committee in November 1966. J575d was then printed and circulated to SAE members in January 1967, subsequently appearing in the 1968 Handbook.

J575d then was "in effect" on February 3, 1967 end before appearing in the 1968 Handbook, whether considered as becoming effective upon approval by the SAE lighting committee or upon publication and distribution to SAE members.

"4. SAE J575d is the revision subreferenced in Table III of Federal Motor Vehicle Safety Standard No. 108 (32 F.R. 18033) under passenger cars, tail lamps (effective January 1, 1969).

Yes. Standard No. 108 was amended to adopt Table III in December 1967, based upon a proposal published on February 3, 1967. The agency did not manifest its intent, in the SPRM or any correspondence that I have been able to discover, that the referenced and subreferenced SAE Standards in the proposed standard were those appearing in the 1967 Handbook (e.g. J575c). It is a general SAE policy, however, as expressed in its Handbooks, that where revision letters are not used, the assumption is that references to Standards will designate the latest revision. Since J575d had been published and circulated in January 1967, it may be reviewed as incorporated by reference into those SAE materials referencing J575 that were part of the NPRM of February 3, 1967.

I hope this answers your questions.

ID: nht72-2.36

DATE: 12/08/72

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: P. F. Middleton, Esq.

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of November 22, 1972 to the National Highway Traffic Safety Administration asking "whether when a school bus is being used to transport pupils, the red lights must go on when the entrance door is opened without exception."

If the system is one of red lamps only, its activation according to SAE Standard J887 is not automatic but manual. The situation differs with respect to the combination amber and red lamps system. Paragraph S4.1.4(b)(ii) of Standard No. 108 effective January 1, 1972, which you reference, states

"The school bus signal lamp system shall be wired so that the amber signal lamps are activated only by manual or foot operation, and if activated, are automatically deactivated and the red signal lamps automatically activated when the bus entrance door is opened."

This means that the red lamps are only activated if the amber lamps have been activated before the door is opened. Activation of the red lamp system is thus dependent upon the action of the bus operator in prior activation of the amber lamp system. From the standpoint of safety we hope that his activation of the amber lamp system will be "without exception" whenever he is transporting pupils.

Because paragraph S3.1.3.2 of Standard No. 108 as it was in effect from January 1, 1969 to January 1, 1972, which you also reference, could mistakenly be interpreted to require activation of the red lamp system without exception whenever the door was opened, the National Highway Traffic Safety Administration adopted the language of S4.1.4 to clarify the ambiguity.

ID: nht72-2.37

DATE: 07/21/72

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: Motor Coach Industries, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of April 17, 1972, in which you requested our interpretation of several sections of Standard 121. I apologize for our delay in replying.

Your first question concerns the air reservoirs which are considered to be included in the service reservoir system. As shown in your diagram, three tanks are capable of providing air to the service brake chambers: the wet air tank, the dry air tank, and the accessory tank. The first two tanks are clearly part of the service reservoir system. The accessory tank, however, has not been generally considered as part of the service brake system, and it is our opinion that it should not be included in computing the reservoir system capacity.

Although the exclusion of the accessory tank from the service reservoir system would seem to weigh against the present location of your pressure gauge in the accessory system circuit, there is another feature of its operation in its present location which leads us to conclude that it would not be acceptable under the present wording of S5.1.4. In the event of a pressure loss in the accessory system (your Condition #1), the gauge would accurately indicate the pressure in the dry tank until the pressure falls to 65 p.s.i., at which point the gauge would cease to indicate the dry tank pressure and would be only an accessory tank gauge. Thus, if the check valve functions properly, the dry tank would be at 65 p.s.i. even though the gauge may read O p.s.i. Because the pressure deliverable to the brake from the service reservoir system would be the 65 p.s.i. of the dry tank, the gauge would not be indicating the service reservoir system air pressure as required by S5.1.4.

Your third question is whether the vehicle must be stationary throughout the static retardation force test of S5.6.1. Our reply is that the vehicle need not remain stationary. Its friction may be overcome by the test pull, although it must exert a force of the magnitude specified in the section.

Your last question relates to the treatment of trailing axles under the requirements of S5.7.1. You indicate that you presently offer an automatic emergency system as an option and that it appears inconsistent to require park brakes on each axle under the automatic application option when they are not required on each axle the other option. We are continuing our evaluation of the parking brake requirements, including the axle-by-axle braking required by S5.7.1. At this time it has not been decided whether to formally institute rulemaking to adjust the requirements. We will advise you if such rulemaking will be forthcoming.

ID: nht72-2.38

DATE: 08/17/72

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: Ford Motor Company

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of July 26, 1972, concerning the adjustment of a tractor's fifth wheel under the test conditions proposed in Docket 70-17, Notice 5.

You state that it is not possible to load the tractor to its GVWR with the tractor's nonsteerable axles and the trailer's axles at GAWR if the fifth wheel is set in more than one position. If this is the case, and the correct loading can be obtained with the fifth wheel in one position only, then only that position will be used in compliance testing. If more than one position can be used to produce the correct loading, the tractor must conform to the requirements of the standard with the fifth wheel at any such position.

ID: nht72-2.39

DATE: 06/13/72

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: Lox Equipment Company

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of May 17, 1972, concerning problems you are having establishing gross axle weight ratings on vehicles you manufacture. You indicate that the problem occurs because brake drums which you use do not come with manufacturer's ratings, but are merely recommended for use with certain axles. You also ask whether a motor vehicle safety standard will require a 40-foot stopping distance from 20 mph.

Your understanding that brake drum capability does not have to be considered in determining gross axle weight rating is not entirely correct. The gross axle weight rating, which is the load carrying capacity of a single axle system (49 CFR 571.3), is a measure of the safe load-carrying capacity of the entire axle system. Manufacturers should include components in their vehicles that are designed to handle loads up to these ratings. Normally an assembler can rely on the specifications or the advice of a reputable supplier as to the capacity of the supplier's components. We expect manufacturers to exercise due care in ensuring that purchased components are adequate and safe for the vehicles they are used on, in accordance with careful business practices. These do not necessarily have to take the form of formal "ratings."

With reference to your question regarding stopping distance, Standard No. 121, Air Brake Systems, effective September 1, 1974 (not July 1, 1972) will, among other things, require a vehicle to stop from 20 mph in 33 and 54 feet on surfaces with skid numbers of 75 and 30 respectively.

ID: nht72-2.4

DATE: 04/03/72

FROM: JAMES E. FORRESTER FOR ROBERT L. CARTER -- NHTSA

TO: Walters Company U.S.A.

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your letter of March 7, 1972, requesting the latest information regarding Federal Motor Vehicle Safety Standard (FMVSS) No. 301, clarification of "leakage" and comments regarding U.S. Patent No. 3, 610, 263.

As amendment to FMVSS No. 301 will be issued in the near future in response to the Notice of Proposed Rule Making published earlier, 35 F.R. (Illegible Word). The substance of this action involves extending the scope of the rule as indicated in the Notice, but the details of the final amendment will not be disclosed before issue. A copy of the Notice is enclosed.

Paragraph S4.4 does not mention leakage but refers to fuel spillage which is defined in S3. There is no assurance that this proposal will remain intact in the final rule since the comments from industry, continued research and development work, and many other inputs will influence the course of this rule making.

We are not in a position to comment on the features of any particular device, since our concern is primarily with performance requirements in order to permit originality and choice of different means for design of improved performance. We appreciate the information about your patented fuel tank safety valve assembly, and shall place a copy of this patent in our Docket No. 70-20. This docket is a public file to receive information and comments on matters pertaining to the rule making action on fuel system integrity.

We appreciate your interest in motor vehicle safety.

ID: nht72-2.40

DATE: 07/19/72

FROM: AUTHOR UNAVAILABLE; C. A. Baker for E. T. Driver; NHTSA

TO: Raybestos-Manhattan

TITLE: FMVSS INTERPRETATION

TEXT: In your letter of June 30, 1972, you raised two questions that touch on the responsibility of manufacturers who produce components, such as brake blocks, that affect the ability of a vehicle to meet a motor vehicle safety standard.

Motor Vehicle Safety Standard No. 121, Air Brake Systems, the standard of concern to you, regulates vehicles equipped with air brakes, but it does not regulate the brakes or their components as separate items of equipment. As a component manufacturer, your company is therefore not required by our regulations to certify its products as conforming to Standard 121. This is not to say that your customers will not be concerned about the performance of your products, but only that you have no direct responsibility under the standard.

A vehicle manufacturer who intends to use your brake blocks on a new vehicle will probably try to get as much test data from you as he can. His vehicle will have to conform to the standard. If our tests disclose a shortcoming in the brakes, he will have to show that he exercised due care in the manufacture of the vehicle and the data he obtains from you may be an important part of his case. Whether you supply him with dynamometer data or complete road test data is a matter to be arranged privately, however, and the subject is not regulated by our rules.

A brake block or other brake component sold as a replacement part is not at this time subject to regulation under Standard 121. A truck owner will presumably want to obtain components that are compatible with the rest of the brake system.

You have also asked for information about agencies equipped to run tests in accordance with Standard 121. At this time we have not compiled a list of test facilities, but we expect that such information will become widely available in the next few months.

ID: nht72-2.41

DATE: 02/28/72

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: Dayton Steel Foundry Company

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of February 2, 1972, in which you asked whether the temperature range specified in S6.2.6 of Motor Vehicle Safety Standard No. 121 was an initial temperature range or a range applicable throughout the stop.

In the new issuance of the standard, published in the February 24, 1972, issue of the Federal Register, the section has been amended to make it clear that the range is the range of initial brake temperature on each stop.

ID: nht72-2.42

DATE: 04/13/72

FROM: AUTHOR UNAVAILABLE; C. A. Baker for E. T. Driver; NHTSA

TO: The Budd Company

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of March 10, 1972, in which you presented a series of questions concerning the meaning of several requirements of Federal Motor Vehicle Safety Standard No. 121, "Air Brake Systems." Our reply deals with the questions in the order you asked them.

1. Your first question concerns the meaning of the statement in section S5.4 that "a brake assembly that has undergone a road test pursuant to S5.3 need not conform to the requirements on this section." To paraphrase your question, the quoted language means that if a given brake assembly is subjected to the road test, the same brake assembly with the used lining need not conform to the dynamometer requirements. Conformity to the dynamometer requirements will be determined by testing an identical brake assembly with new linings. The petitions for deletion of dynamometer testing would have made the road test the only test. The standard requires both tests, even though two sets of identical brakes will be used, and our statement that the petitions were denied is therefore correct.

2. You point out that the measurement interval used in S5.4.1.1 for determining average torque, which begins when a specified pressure is reached, differs from the interval specified in S5.4 for measuring deceleration, which begins with the onset of deceleration. Although we agree that you may need different instrumentation for measuring average torque and average deceleration, we do not agree that their is any conflict since average torque and average deceleration are not required to be measured at the same time. We consider the present method of measuring torque and deceleration to be the correct methods.

3. The typographical error in section S5.4.1.1, which you have correctly edited to read "Repeat the procedure six times, increasing the brake chamber air pressure by 10 psi each time," has been corrected by a revision in the March 29, 1972, Federal Register.

4, 5, 6. The requirements of S5.4.2, S5.4.2.1 and S5.4.3 concerning average deceleration rates should not be understood to mean that a manufacturer, in his own testing, must test at exactly that rate. It is advisable for him to test in a manner that offers assurance that the brakes will pass when tested in the manner specified in the standard. Typically, where a test value such as 9 fpsps is specified, manufacturers tend to use more adverse values in their own testing. Under the former wording of these sections, the compliance agency could have tested brakes at decelerations higher than the specified minimum, and it would have been much more difficult for a manufacturer to ascertain his "worst case" situation.

The notice proposing to amend the weight conditions for truck-tractors should be issued within the next two months.