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NHTSA Interpretation File Search

Overview

NHTSA's Chief Counsel interprets the statutes that the agency administers and the standards and regulations that it issues. Members of the public may submit requests for interpretation, and the Chief Counsel will respond with a letter of interpretation. These interpretation letters look at the particular facts presented in the question and explain the agency’s opinion on how the law applies given those facts. These letters of interpretation are guidance documents. They do not have the force and effect of law and are not meant to bind the public in any way. They are intended only to provide information to the public regarding existing requirements under the law or agency policies. 

Understanding NHTSA’s Online Interpretation Files

NHTSA makes its letters of interpretation available to the public on this webpage. 

An interpretation letter represents the opinion of the Chief Counsel based on the facts of individual cases at the time the letter was written. While these letters may be helpful in determining how the agency might answer a question that another person has if that question is similar to a previously considered question, do not assume that a prior interpretation will necessarily apply to your situation.

  • Your facts may be sufficiently different from those presented in prior interpretations, such that the agency's answer to you might be different from the answer in the prior interpretation letter;
  • Your situation may be completely new to the agency and not addressed in an existing interpretation letter;
  • The agency's safety standards or regulations may have changed since the prior interpretation letter was written so that the agency's prior interpretation no longer applies; or
  • Some combination of the above, or other, factors.

Searching NHTSA’s Online Interpretation Files

Before beginning a search, it’s important to understand how this online search works. Below we provide some examples of searches you can run. In some cases, the search results may include words similar to what you searched because it utilizes a fuzzy search algorithm.

Single word search

 Example: car
 Result: Any document containing that word.

Multiple word search

 Example: car seat requirements
 Result: Any document containing any of these words.

Connector word search

 Example: car AND seat AND requirements
 Result: Any document containing all of these words.

 Note: Search operators such as AND or OR must be in all capital letters.

Phrase in double quotes

 Example: "headlamp function"
 Result: Any document with that phrase.

Conjunctive search

Example: functionally AND minima
Result: Any document with both of those words.

Wildcard

Example: headl*
Result: Any document with a word beginning with those letters (e.g., headlamp, headlight, headlamps).

Example: no*compl*
Result: Any document beginning with the letters “no” followed by the letters “compl” (e.g., noncompliance, non-complying).

Not

Example: headlamp NOT crash
Result: Any document containing the word “headlamp” and not the word “crash.”

Complex searches

You can combine search operators to write more targeted searches.

Note: The database does not currently support phrase searches with wildcards (e.g., “make* inoperative”). 

Example: Headl* AND (supplement* OR auxiliary OR impair*)
Result: Any document containing words that are variants of “headlamp” (headlamp, headlights, etc.) and also containing a variant of “supplement” (supplement, supplemental, etc.) or “impair” (impair, impairment, etc.) or the word “auxiliary.”

Search Tool

NHTSA's Interpretation Files Search



Displaying 11991 - 12000 of 16517
Interpretations Date

ID: nht79-4.16

Open

DATE: 05/09/79

FROM: STEPHEN P. WOOD FOR FRANK BERNDT, NHTSA

TO: Management Consulting in Product Assurances

TITLE: FMVSR INTERPRETATION

TEXT: This responds to your April 9, 1979, letter asking how the agency will apply the reporting requirements of Part 573, Defect and Noncompliance Reports, to equipment manufacturers.

As the agency indicated in the preamble to the final rule, replacement equipment manufacturers that are required to notify owners and to remedy defective or noncomplying equipment would do so to the best of their abilities. The reporting requirement does not require them to manufacture their equipment so that it is easily identifiable nor does it require them to maintain lists of persons to whom equipment has been sold. Some equipment manufacturers may wish to upgrade their recordkeeping and identification systems to facilitate their statutory obligations to recall and remedy, but the reporting regulation does not require this.

With respect to the "flasher" incident to which you refer in your letter, if a vehicle manufacturer authorizes the use of incorrect flashers in its vehicles, problems resulting from the use of those flashers would be the responsibility of the vehicle manufacturer not the equipment manufacturer. The problem that you describe is one of incorrect use of properly functioning equipment. It is not a problem of defective equipment.

Sincerely,

ID: nht79-4.17

Open

DATE: 05/17/79

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: Yokohama Tire Corporation

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your letter of April 27, 1979, asking whether Yokohama Tire Corporation's point-of-sale information leaflet conforms to the requirements of the Uniform Tire Quality Grading Standards (49 CFR 575.104(d)(1)(ii). While the National Highway Traffic Safety Administration does not typically issue advance judgments concerning compliance with agency regulations, your proposed point-of-sale leaflet appears to meet the requirements of section 575.104(d)(1)(ii), assuming the listing at the bottom of the page contains each tire manufactured by Yokohama which is offered for sale at the location where the leaflet is distributed.

SINCERELY,

YOKOHAMA TIRE CORPORATION

April 27, 1979

Richard Hipolit Office of Chief Council National Highway Traffic Safety Administration

Dear Mr. Hipolit:

Attached is the information I talked to you on April 27, 1979. Please make any correction or changes so this letter will fall within the D. O. T. guideline.

Thank you for your assistance.

Jim Buck National Service Manager Yokohama Tire Corporation

DOT QUALITY GRADES ALL PASSENGER CAR TIRES MUST CONFORM TO FEDERAL SAFETY REQUIREMENTS IN ADDITION TO THESE GRADES TREADWEAR

The treadwear grade is a comparative rating based on the wear rate of the tire when tested under controlled conditions on a specified government test course. For example, a tire graded 150 would wear one and a half (1-1/2) times as well on the government course as a tire graded 100. The relative performance of tires depends upon the actual conditions of their use, however, and may depart significantly from the norm due to variations in driving habits, service practices and differences in road characteristics and climate.

TRACTION

The traction grades, from highest to lowest are A, B, and C, and they represent the tire's ability to stop on wet pavement as measured under controlled conditions on specified government test surfaces of asphalt and concrete. A tire marked C may have poor traction performance. Warning: The traction grade assigned to this tire is based on braking (straightahead) traction tests and does not include cornering (turning) traction.

TEMPERATURE

The temperature grades are A (the highest), B, and C representing the tire's resistance to the generation of heat and its ability to dissipate heat when tested under controlled conditions on a specified indoor laboratory test wheel. Sustained high temperature can cause the material of the tire to degenerate and reduce tire life, and excessive temperature can lead to sudden tire failure. The grade C corresponds to a level of performance which all passenger car tires must meet under the Federal Motor Vehicle Safety Standard No. 109, Grades B and A represent higher levels of performance on the laboratory test wheel than the minimum required by law. Warning: The temperature grade for this tire is established for a tire that is properly inflated and not overloaded. Excessive speed, underinflation, or excessive loading, either separately or in combination, can cause heat buildup and possible tire failure. Tire Size Load Tread Tubeless/ Trd Designation Range Pattern Tube Type Side Wall Wear Traction Temp. 155S13/6.15 $ 13 B Y205 Tubeless Black 80 B B 4PR 155-13/6.15-13 B Y205 Tubeless Black 80 B C 4PR 165S13/6.45S13 B Y205 Tubeless WhiteRibbon 80 B B 4PR 7.00-14-6PR C Y205 Tubeless Black 80 B C 7.00-14-6PR C Y205 Tubeless WhiteRibbon 80 B C H78-15 B Y820 Tubeless Black 80 B C

ID: nht79-4.18

Open

DATE: 07/05/79

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: Subaru of America Inc.

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your letter of June 4, 1979, concerning Subaru's obligation to provide to prospective motor vehicle purchasers an explanation of the Uniform Tire Quality Grading (UTQG) Standards (49 CFR 575.104(d)(1)(ii)). You ask whether Subaru must provide UTQG information to prospective purchasers prior to April 1, 1980, in view of the fact that all motor vehicles sold by your company are equipped with radial tires.

With respect to radial tires, the effective date for all requirements of the UTQG regulation, other than the molding requirement of paragraph (d)(1)(i)(A) and the first purchaser requirement of paragraph (d)(1)(iii), is April 1, 1980. Therefore, manufacturers, such as Subaru, which offer for sale only motor vehicles equipped with radial tires, need not provide UTQG information for examination by prospective purchasers prior to April 1, 1980.

Sincerely,

ATTACH.

June 4, 1979

Richard J. Hipolit -- National Highway Traffic Safety Administration

Dear Mr. Hipolit:

In our telephone conversation on Friday, June 1, you confirmed my interpretation of the requirement for the date of publication of "Tire Quality Grading Information" for our prospective purchasers is dependent upon the effective date of the regulation. As we only use radial tires, the grading regulation effective date for which is April 1, 1980, our obligation to issue information to prospective purchasers is also April 1, 1980.

If this is still your opinion will you please confirm this in writing?

Thank you.

Yours very truly,

SUBARU OF AMERICA, INC.;

D. J. Schrum -- Manager Product Compliance

ID: nht79-4.19

Open

DATE: 03/30/79

FROM: AUTHOR UNAVAILABLE; Michael M. Finkelstein; NHTSA

TO: Rubber Manufacturers Association

TITLE: FMVSR INTERPRETATION

TEXT: In your letter of March 19, you pointed out that the tire industry has printed tire lables and consumer information materials based on Figure 2 of the Uniform Tire Quality Grading (UTQG) Standards (49 CFR 575.104), as published in the National Highway Traffic Safety Administration's (NHTSA) Docket 25, Notice 24 (43 FR 30542; July 17, 1978). That notice contained a typographical error in the text of Figure 2, which was corrected in Notice 31 (44 FR 15721, March 15, 1979) by substitution of the word "are" in place of the word "of" in the first line of the third section of Figure 2.

The labels and other materials printed prior to the issuance of Notice 31 may be technically in noncompliance with the UTQG regulation. To avoid the waste which would result if use of these materials were prohibited, however, NHTSA will permit use of tread labels and information materials containing the Figure 2 text as stated in Notice 24, where orders for printing of these materials were submitted prior to March 15, 1979, the date of publication of Notice 31.

ID: nht79-4.2

Open

DATE: 10/30/79

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Wanger Electric Corporation

TITLE: FMVSS INTERPRETATION

TEXT:

NOA-30

Mr. J. W. Kourik Chief Engineer, Brake Products Wagner Electric Corporation 11444 Lackland Road St. Louis, Missouri 63141

Dear Mr. Kourik:

This responds to your September 17, 1979, letter asking whether Standard No. 121, Air Brake Systems, permits manufacturers to install antilock devices on only one axle of a multi-axle vehicle. The answer to your question is yes.

As you know, the decision in PACCAR v. NHTSA, 573 F.2d 632 (9th Cir. 1978); cert. den'd, 439 U.S. 862 (Oct. 2, 1978) invalidated the antilock requirements as they apply to trucks and trailers. Accordingly, the anti-lock provisions of the standard no longer apply to those vehicles. A manufacturer that desires to install anti-lock devices can do so at its own discretion and to any extent that it considers appropriate. This includes the installation of antilock devices on only one axle. Of course, any installation of devices affecting braking must not impair the brake system's compliance with the standard.

Sincerely,

Frank Berndt Chief Counsel

September 17, 1979

National Highway Traffic Safety Administration Office of Chief Counsel Room 5219 Nassif Building Washington, D.C. 20590

Gentlemen:

Wagner agrees with the NHTSA position recognizing the benefits of antilock in their recommendation that antilock systems on existing vehicles be maintained in proper working condition.

In regard to existing and newly manufactured equipment, Wagner is aware that according to Notice 26 of Docket 75-16 dated 8/9/79:

"...the court's remand (9th District Court of Appeals, PACCAR vs. NHTSA and DOT)...precludes the agency from enforcing compliance with any road test requirement for trucks and trailers at any speed on wet or dry surfaces."

And also, as stated in Notice 01 of Docket 79-03 dated 2/15/79:

"...users...may order antilock according to their choice on new vehicles."

Wagner interprets that it is acceptable for manufacturers to equip fewer than all axles of a multi-axle vehicle for antilock control. Therefore, users who do elect to use antilock may choose, for example, a single anti-lock system for only one axle (in lieu of tandem control or axle-by-axle control) on a tandem axle trailer.

Wagner requests confirmation on our interpretation regarding acceptability of installations where fewer than all axles on a vehicle are under antilock control.

Very truly yours,

WAGNER ELECTRIC CORPORATION

J. W. Kourik, Chief Engineer Brake Products

JWK:DSQ:san

ID: nht79-4.20

Open

DATE: 10/15/79

FROM: AUTHOR UNAVAILABLE; Stephen P. Wood; NHTSA

TO: Federal Trade Commission/PC

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your letter of September 11, 1979, asking whether the National Highway Traffic Safety Administration (NHTSA) has adopted the Rubber Manufacturers Association (RMA) definition of mud and snow tire or has made any official statement regarding the validity of that definition. NHTSA has not adopted the RMA definition for use in any agency regulations, relating either to safety standards or to tire quality grading, nor has NHTSA made any official statement regarding the validity of the definition. If I can be of further assistance, do not hesitate to contact me.

Sincerely,

ATTACH.

FEDERAL TRADE COMMISSION/PC

SEPTEMBER 11, 1979

Dick Hipolit, Esquire -- Office of Chief Counsel, National Highway Traffic Safety Agency

Dear Mr. Hipolit:

Pursuant to our conversation of September 11, 1979, I would appreciate if you would inform me whether N.H.T.S.A. has adopted the industry standard of the Rubber Manufacturers Association's definition of a mud and snow tire or has offered any opinions regarding its validity.

The definition states that: "The characteristics of a mud and snow tire are:

(a) A substantial portion of the lug, block, or rib edges in the tread design are at an angle greater than 30 degrees to the tire circumferential center line.

(b) On at least one side of the tread design, the shoulder lugs protrude at least 1/2" in a direction generally perpendicular to the direction of travel."

The above information may be sent to Jeff Jacobovitz, Federal Trade Commission/PC, 6th & Pennsylvania Avenue, N.W., Washington, D.C. 20580.

Thank you.

Sincerely, Jeff Jacobovitz -- Legal Intern, Division of Compliance

ID: nht79-4.21

Open

DATE: 12/05/79

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: Michelin Tire Corp.

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your letter of November 19, 1979 asking for clarification of the tire manufacturer's responsibility, as of April 1, 1980, for providing Uniform Tire Quality Grading (UTQG) point of sale information for radial tires sold as original equipment on new passenger cars. You also ask what the original equipment tire manufacturer's responsibility will be for providing UTQG information as of October 1, 1980.

The UTQG Standards (49 CFR 575.104) require that tire grading information be made available to consumers by several means. Grading information must be molded on the tire sidewall (49 CFR 575.104(d)(1)(i)(A)), contained in a label affixed to the tread surface (49 CFR 575.104 (d)(1)(i)(B), and furnished under 49 CFR 575.6(a) and (c) to motor vehicle first purchasers and to prospective purchasers of vehicles and tires (49 CFR 575.104(d)(1)(ii) and (iii)).

For radial tires, the effective date for sidewall molding is October 1, 1980, regardless of whether the tire is sold for use as original equipment on a new vehicle or as a replacement tire. However, the tread labeling requirement, effective April 1, 1980 in the case of radial tires, specifically exempts tires sold as original equipment on new vehicles. Therefore, the tire manufacturer is not responsible for the attachment of UTQG tread labels to tires which are in fact sold for use as original equipment on new vehicles.

Motor vehicle and tire manufacturers are responsible under 49 CFR 575.104(d)(1)(ii) and 575.6(c) for providing certain UTQG point of sale information to prospective purchasers of their products. This requirement, which in the case of original equipment tires does not necessitate display of the specific UTQG grades applicable to particular tires; takes effect April 1, 1980, for radial tires.

Pursuant to 49 CFR 575.104(d)(1)(iii) and 575.6(a), first purchasers of vehicles equipped with radial tires manufactured after October 1, 1980 must be supplied with an explanation of the UTQG system containing a statement referring the reader to the tire sidewall for specific UTQG grades. However, responsibility for supplying this information rests with the motor vehicle manufacturer rather than the tire manufacturer.

Sincerely,

ATTACH.

November 19, 1979

DICK HIPLETT -- Office of the Chief Counsel, National Highway Traffic Safety Administration

Dear Sir: Would you please clarify for us what the original equipment manufacturers' responsibility will be as of April 1, 1980 regarding point of sales UTQG information for radial tires.

Also, what will the original equipment manufacturers' responsibility be regarding consumer UTQG information as of October 1, 1980.

Thank you.

Yours truly, MICHELIN TIRE CORPORATION Technical Group; John B. White -- Engineering Manager, Technical Information Dept.

ID: nht79-4.22

Open

DATE: 02/07/79

FROM: JOSEPH J. LEVIN -- CHIEF COUNSEL, NHTSA; SIGNATURE BY STEPHEN P. WOOD

TO: Leon Conner

TITLE: FMVSR INTERPRETATION

TEXT: We understand that a question has arisen concerning the testing of "P-type" tires under the traction grading procedures of the Uniform Tire Quality Grading (UTQG) Standards (49 CFR 575.104(f)(2)). Under the terms of the regulation, candidate tires are to be inflated to 24 psi prior to the traction test (49 CFR 575.104(f)(2)(i)(B) and (D), and (f)(2)(viii)), and are to be loaded to 85 percent of the load specified in Appendix A of FMVSS No. 109 (49 CFR 571.109), for the tires' size designation, at a cold inflation pressure of 24 psi (49 CFR 575.104(f)(2)(viii)). However, Appendix A lists cold inflation pressures for "P-type" tires in kilopascals, with no stated inflation pressure corresponding precisely to 24 psi.

NHTSA chose 24 psi as the stated inflation pressure for UTQG traction testing since it represents the recommended tire inflation pressure for most passenger cars. In the situation where no cold inflation pressure exactly equivalent to the specified pressure of 24 psi is stated in Appendix A of FMVSS No. 109 for a tire size designation, the tires to be tested are inflated to the pressure, listed for the tire size designation in Appendix A, which is nearest to 24 psi, i.e., 180 kPa for tires with inflation pressures measured in kilopascals. The tires are then loaded to 85 percent of the load specified in Appendix A for the inflation pressure thus determined. The agency plans to issue an interpretive amendment to the regulation clarifying this point.

ID: nht79-4.23

Open

DATE: 10/22/79

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: Uniroyal GmbH

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your letter of October 12, 1979, asking whether the character height of 5/32nds of an inch, stated in the Uniform Tire Quality Grading (UTQG) Standards (49 CFR 575.104, Figure 1), is considered by the National Highway Traffic Safety Administration (NHTSA) to specify the only acceptable height for UTQG sidewall molding, or whether the agency interprets this measurement as a minimum value.

The specification of 5/32nds of an inch tire sidewall characters was intended by NHTSA to establish a minimum requirement to assure readability of the UTQG information presented. The agency has no objection to the use of characters of a height greater than 5/32nds of an inch, so long as all characters used to convey UTQG information are of the same height.

ID: nht79-4.24

Open

DATE: 08/14/79

FROM: Frank Berndt; NHTSA

TO: Uniroyal GMBH

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your letter of July 20, 1979, concerning the Uniform Tire Quality Grading (UTGQ) Standards (49 CFR 575.104). You ask whether it is permissible under the regulation to mold UTQG grades on only one sidewall of a tire and, in the case of a symmetrical black sidewall tire, whether the grades may be molded on the same sidewall as the tire identification number required by 49 CFR 574.5.

The UTQG Standards require that tire grades need be molded on only one sidewall of a tire. Since the regulation presently does not specify the sidewall on which tire grades must be molded, Uniroyal is legally permitted to mold UTQG grades on either sidewall of its tires. However, in order to facilitate consumer access to the grading information, the National Highway Traffic Safety Administration (NHTSA) encourages manufacturers to mold tire grades on the sidewall intended to be visible when the tire is mounted on a vehicle. NHTSA will monitor the placement of tire trades to determine whether further action is necessary to assure the accessibility of the grading information.

Request an Interpretation

You may email your request to Interpretations.NHTSA@dot.gov or send your request in hard copy to:

The Chief Counsel
National Highway Traffic Safety Administration, W41-326
U.S. Department of Transportation
1200 New Jersey Avenue SE
Washington, DC 20590

If you want to talk to someone at NHTSA about what a request for interpretation should include, call the Office of the Chief Counsel at 202-366-2992.

Please note that NHTSA’s response will be made available in this online database, and that the incoming interpretation request may also be made publicly available.

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