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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 2051 - 2060 of 2914
Interpretations Date

ID: aiam2621

Open
Mr. Jack Gromer, Vice President - Technical Operations, Timpte, Inc., 5990 N. Washington Street, Denver, CO 80216; Mr. Jack Gromer
Vice President - Technical Operations
Timpte
Inc.
5990 N. Washington Street
Denver
CO 80216;

Dear Mr. Gromer: This responds to your May 6, 1977, letter asking whether your tir information label complies with the requirements of Standard No. 120, *Tire Selection and Rims for Motor Vehicles Other Than Passenger Cars, and Part 567, *Certification*. Further, you request that the National Highway Traffic Safety Administration (NHTSA) expedite treatment of Docket No. 73-31, Notice 1, which, if implemented would simplify the certification and information labels.; Concerning Docket 73- 31, the NHTSA published on June 20, 1977, notice (42 FR 31161) implementing Notice 1 which proposed the use of the designation 'all axles' rather than listing each axle individually on the certification label. The implementation of this regulation should resolve many of your problems.; Regarding the sample information label you submitted with your letter the NHTSA does not give advance approvals of compliance with Federal safety regulations or standards. We will, however, give an informal opinion of whether your label appears to comply with the requirements. The label you submitted does not appear to comply with the requirements of Part 567 or Standard No. 120. I have enclosed copies of both of these regulations for your information.; Your certification label should use the designation 'all axles' no 'each axle.' The tire and rim information should follow that designation stated in the form presented in the examples in Standard No. 120 and Part 567.; Sincerely, Joseph J. Levin, Jr., Chief Counsel

ID: aiam2949

Open
Mr. Leon Conner, P.O. Box 1671, San Angelo, TX 76902; Mr. Leon Conner
P.O. Box 1671
San Angelo
TX 76902;

Dear Mr. Conner: We understand that a question has arisen concerning the testing o '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 tractio 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.; Sincerely, Joseph J. Levin, Jr., Chief Counsel

ID: aiam0489

Open
Mr. James Eckstein, 3025 St. Paul Street, Baltimore, Maryland 21218; Mr. James Eckstein
3025 St. Paul Street
Baltimore
Maryland 21218;

Dear Mr. Eckstein: This is in reply to your letter of August 27, 1971, which was forwarde to this office October 20, 1971, by the Federal Trade Commission, regarding Government specifications for retreaded tires. You refer to problems you believe result from 'out of roundness,' specifically, abnormal wear and blowouts at normal boulevard and highway speeds. You wish to determine whether this problem results from 'too lenient' Government requirements, or whether 'manufacturers are negligent.'; Out-of-roundness can occur in a retreaded tire for numerous reasons and its presence does not necessarily indicate negligence on the part of the manufacturer. Moreover, while an out-of-round tire may affect vehicle handling it generally does not blow out at normal boulevard or even highway speeds, as result of the out-of-round condition. Thus, a blow out in an out-of-round tire could have resulted from other factors. Many tire dealers, in addition, have machines that can eliminate out-of-roundness by cutting of excess tread.; With reference to Federal regulations of retreaded tires, the firs such regulation will become effective January 1, 1972. This regulation, Motor Vehicle Safety Standard No. 117, 'Retreaded Pneumatic Tires,' specifies size and performance requirements for retreaded tires for use on passenger cars. There requirements are similar to those that have been applicable to new passenger car tires since January 1, 1968. None of these requirements specifically concern 'out-of-roundness.' We do not have evidence that this characteristic, by itself, is a safety problem.; Sincerely, Richard B. Dyson, Assistant Chief Counsel

ID: 77-4.43

Open

TYPE: INTERPRETATION-NHTSA

DATE: 12/01/77

FROM: AUTHOR UNAVAILABLE; J. J. Levin, Jr.; NHTSA

TO: Nissan Motor Co., Ltd.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your telephone conversation of November 9, 1977, with Roger Tilton of my staff concerning the applicability of the tire performance standard (Standard No. 109. New Pneumatic Tires -- Passenger Cars) to temporary-use spare tires.

The National Highway Traffic Safety Administration has permitted the manufacture of temporary-use spare tires because they are smaller than regular spare tires and thus when carried in the automobile reduce its overall weight. A reduction in motor vehicle weight can result in increased fuel efficiency of the vehicle. These tires must comply with all of the safety requirements applicable to passenger car tires.

ID: nht68-3.1

Open

DATE: 05/17/68

FROM: AUTHOR UNAVAILABLE; David A. Fay; NHTSA

TO: Berliner Motor Corporation

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your letter of April 10, 1968, addressed to Mr. William H. Risteen, concerning the requirement for headlamp dimmer switches as specified in Federal Motor Vehicle Safety Standard No. 108.

Paragraph S3.4.1 of Standard No. 108 requires that a means for switching between lower and upper headlamp beams shall be provided in accordance with SAE Recommended Practice J564a or J565a. This general requirement is applicable to all vehicles, including motocycles, that are required, by Standard No. 106, to be equipped with lower and upper bean headlamps, even though SAE Recommended Practice J564a is addressed only to passenger cars.

Thank you for writing.

ID: nht71-5.1

Open

DATE: 11/17/71

FROM: AUTHOR UNAVAILABLE; J. W. Carson for E. T. Driver; NHTSA

TO: Ward School Bus Mfg., Inc.

TITLE: FMVSS INTERPRETATION

TEXT: Your letter of October 28, 1971, to Mr. Stan Haranski, Truck Body and Equipment Association, Inc., concerning switching arrangements for school bus red signal lamps, has been forwarded to this Office for reply.

Paragraph S4.1.4(a) of Federal Motor Vehicle Safety Standard No. 108 requires that the four red signal lamps be controlled by a manually actuated switch. A two-way switch, whereby all four lamps are activated when the switch is in one position, and the two rear lamps only are activated when the switch is in the opposite position, would not be in violation of this requirement of Standard No. 108.

ID: nht73-4.47

Open

DATE: 08/13/73

FROM: AUTHOR UNAVILABLE; Richard B. Dyson; NHTSA

TO: SCARTI

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of July 19, 1973, to the Administrator.

The exemption provided vehicles with a curb weight of 1,000 pounds or less will cease to exist as of January 1, 1974, and lightweight vehicles manufactured on or after that date will be required to meet all Federal motor vehicle safety standards applicable to their vehicle category, e.g. passenger cars.

Under the circumstances you indicate, you would be the final-stage manufacturer of a vehicle manufactured in two or more stages, under 49 CFR Parts 567 and 568 of our regulations. We refer you specifically to sections 567.5 and 568.6 of those regulations.

ID: nht91-1.8

Open

DATE: January 3, 1991

FROM: S.V. Kaaria

TO: NHTSA

TITLE: None

ATTACHMT: Attached to letter dated 2-11-91 from Paul Jackson Rice to S.V. Kaaria (A37; Std. 108); Also attached to letter dated 1-16-91 from Marvin A. Leach, to S.V. Kaaria (OCC 5648)

TEXT:

I am the designer of the taillights placed near the rear window of passenger cars. In attempting to negotiate a settlement with auto manufacturers, they all point to the law which requires these new placements of elevated brake lights (Standard 108.1.1.27). They claim since you made the requirements you should negotiate with me for 1% of replacement cost of these taillights.

Would you please clarify your position in this matter, and notify me. Thank you.

ID: nht92-7.39

Open

DATE: April 16, 1992

FROM: Neil Friedkin -- Attorney at Law

TO: Marvin Shaw -- NHTSA, U.S. DOT

TITLE: None

ATTACHMT: Attached to letter dated 6/15/92 from Paul J. Rice to Neil Friedkin (A39; Std. 108; Std. 208; Std. 216); Also attached to letter dated 4/13/92 from Paul Jackson Rice to Neil Friedkin

TEXT:

Enclosed is a copy of the letter provided to me by Paul Jackson Rice on April 13, 1992.

I would appreciate your providing me with the applicable 1986 standard for convertible passenger cars, if possible.

Once again, thank you for your courtesy and cooperation.

Attachment

NHTSA interpretation letter dated 4/13/92 from Paul J. Rice to Neil Friedkin. (Text omitted here.)

ID: nht75-3.13

Open

DATE: 06/25/75

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Emmons Brothers

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your letter of May 1, 1975, concerning Federal Motor Vehicle Safety Standard No. 302, Flammability, and in amplification of your telephone conversation with Mr. Schwartz of my office.

As Mr. Schwartz advised you, Standard No. 302 applies to passenger cars, multipurpose passenger vehicles, trucks, and buses. Thus, the standard would apply to mattresses used in trucks. Further, it has been proposed to extend Standard No. 302 to campers and trailers other than those sold exclusively for the transportation of cargo (copy enclosed). Consequently, as you requested, I have enclosed a copy of Motor Vehicle Safety Standard No. 302, a recent amendment to that standard, and a proposed amendment which may also be of interest to you.

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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