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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 16161 - 16170 of 16490
Interpretations Date

ID: nht89-1.45

Open

TYPE: INTERPRETATION-NHTSA

DATE: 03/20/89

FROM: M. IWASE -- TECHNICAL ADMINISTRATION DEPT. KOITO MFG. CO., LTD.

TO: ERIKA Z. JONES -- CHIEF COUNSEL NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION

TITLE: NONE

ATTACHMT: ATTACHED TO LETTER DATED 06/19/89 FROM ERIKA Z. JONES -- NHTSA TO M. IWASE; REDBOOK A33; STANDARD 108

TEXT: Dear Ms. Jones,

Koito would like to confirm the following prescription of license plate lamp in Table II and IV of FMVSS No. 108.

TABLE II - LOCATION OF REQUIRED EQUIPMENT Location on Height above Item Multipurpose passenger Trailers road surface vehicles, trucks, and busses measuredLicense At rear license plate, to At rear license plate, to No plate illuminate the plate from the illuminate the plate from requirement lamp top or sides. the top or sides. TABLE IV - LOCATION OF REQUIRED EQUIPMENT Location on Height above Item Passenger cars, multipurpose Motorcycles road surface passenger vehicles, measuredLicense At rear license plate, to At rear license plate No plate illuminate the plate from the requirementlamp top or sides.

We interpret that the license plate lamp is not permitted to illuminate the plate from the bottom (except Motorcycle).

We would greatly appreciate if you would kindly and promptly give us your confirmation as to whether the illumination from the bottom be permissible.

Sincerely yours,

ID: 77-4.46

Open

TYPE: INTERPRETATION-NHTSA

DATE: 12/05/77

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

TO: Rocky Mountain Bandag

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your October 19, 1977, letter asking whether the National Highway Traffic Safety Administration (NHTSA) has regulations that prohibit the use of retreaded tires on steering axles.

The NHTSA has performance regulations applicable to retreaded passenger car tires. The agency does not regulate the use of retreaded tires that meet those performance requirements. You should note that the Bureau of Motor Carrier Safety has regulations (49 Code of Federal Regulations Part 393.75(d)) that prohibit the use of retreaded tires on the front wheels of buses under their jurisdiction. They do not prohibit the use of such retreaded tires on the steering axle of trucks, however.

SINCERELY,

ROCKY MOUNTAIN bandag

October 19, 1977

Director U. S. Department of Transportation National Highway Traffic Safety Administration

We are in the business of cold process retreading truck tires.

Quite frequently, truck owners tell us there's a D.O.T. regulation that says retreaded tires cannot be used on steering axles. To our knowledge, there is no such regulation. If we're correct, would you please send a letter that says there is no D.O.T. regulation that disallows use of retreads on the steering axle?

William H. Loughran President

ID: 2860yy

Open

Mr. Billy S. Peterson
President
Automotive Safety Testing, Inc.
at TRC of Ohio, Bldg. 20
Rd. 152 & SR 33
East Liberty, OH 43319

Dear Mr. Peterson:

This is in reply to your letter of February 7, l99l, to the Office of Chief Counsel asking for a clarification of allowable mounting locations and photometric output requirements for tail/stop lamps on passenger cars.

One of your clients wishes to mount "two-part" stop/tail lamps "so that one lamp is mounted on the fixed quarter panel and a duplicate lamp is mounted on the trunk lid." Each part of the two-part lamp is a combination tail/stop lamp. You have asked whether the minimum photometric requirements must be met by "the lamp mounted to the quarter panel or may the portion mounted on the trunk lid count toward the photometric requirements."

Your "two-part lamp" would be treated as two separate lamps. For purposes of compliance, only one of these two adjacent lamps must be designed to conform to Standard No. l08, and this conformance must be independent of any "contribution" by the adjacent lamp. Although Standard No. l08 permits either the deck or the body mounted lamp to be the complying lamp, it would be our preference that the body mounted lamp be the one that complies, so that the benefit of a conforming stop/tail lamp would be realized during those occasions when the lid may be raised.

Sincerely,

Paul Jackson Rice Chief Counsel

/ref:l08 d:3/8/9l

2009

ID: nht91-2.20

Open

DATE: March 8, 1991

FROM: Paul Jackson Rice -- Chief Counsel

TO: Billy S. Peterson -- President, Automotive Safety Testing, Inc. at TRC of Ohio

TITLE: None

ATTACHMT: Attached to letter dated 2-7-91 from Billy S. Peterson to Office of Chief Council (OCC 5709)

TEXT:

This is in reply to your letter of February 7, 1991, to the Office of Chief Counsel asking for a clarification of allowable mounting locations and photometric output requirements for tail/stop lamps on passenger cars.

One of your clients wishes to mount "two-part" stop/tail lamps "so that one lamp is mounted on the fixed quarter panel and a duplicate lamp is mounted on the trunk lid." Each part of the two-part lamp is a combination tail/stop lamp. You have asked whether the minimum photometric requirements must be met by "the lamp mounted to the quarter panel or may the portion mounted on the trunk lid count toward the photometric requirements."

Your "two-part lamp" would be treated as two separate lamps. For purposes of compliance, only one of these two adjacent lamps must be designed to conform to Standard No. 108, and this conformance must be independent of any "contribution" by the adjacent lamp. Although Standard No. 108 permits either the deck or the body mounted lamp to be the complying lamp, it would be our preference that the body mounted lamp be the one that complies, so that the benefit of a conforming stop/tail lamp would be realized during those occasions when the lid may be raised.

ID: nht87-2.60

Open

TYPE: INTERPRETATION-NHTSA

DATE: JULY 30, 1987

FROM: LEONARD CAIN -- DIRECTOR, SCHOOL BUILDING AND TRANSPORTATION - MISSISSIPPI DEPT. OF EDUCATION

TO: JOAN TILLMAN -- NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION

ATTACHMT: FEBRUARY 23, 1988 LETTER FROM JONES TO CAIN

TEXT: In our telephone conversation yesterday, you made reference to not having any knowledge of Standard 17. Through the years this division has received numerous communiques from the National Highway Traffic Safety Administration regarding Standard 17 and i ts application for transporting students to and from school and related activities.

Enclosed is a copy of a Notice from the NHTSA making reference to Standard 17, Pupil Transportation Safety. You will note on page 2 of this notice that the last paragraph makes specific reference to color under the definition of school bus identificatio n and marking requirements.

Would you please provide an official interpretation of the Federal Motor Vehicle Safety Standards for school buses regarding the following questions:

(1) Does a vehicle (type 1 bus) purchased by a local public school district for transporting students for only activity purposes have to conform to all Federal Motor Vehicle Safety Standards? Does a bus purchased and used solely for activity purposes ha ve to be painted school bus yellow?

(2) Does a van (designed to carry 11 or more persons) purchased by a local public school district for transportating students for only activity purposes have to conform to all Federal Motor Vehicle Safety Standards? Does a van purchased and used solely for activity purposes have to be painted school bus yellow?

Your help is sincerely appreciated.

ID: nht71-3.12

Open

DATE: 06/02/71

FROM: L. R. SCHNEIDER -- NHTSA; SIGNATURE BY DAVID SCHMELTZER

TO: Truck Trailer Manufacturers Association

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of May 28, 1972, requesting clarification of whether a vehicle manufacturer, under 574.10 of the Tire Identification and Record Keeping regulation, may designate someone to maintain the records for his.

This letter is to confirm that motor vehicle manufacturers may assign a designee for the record keeping requirements of Part 574.

ID: nht72-6.43

Open

DATE: 01/20/72

FROM: AUTHOR UNAVAILABLE; E.T. Driver; NHTSA

TO: Crestview Service Center

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of January 7, 1972, regarding recordkeeping of tires manufactured before May 22, 1971.

Tires manufactured prior to May 22, 1971, are not subject to the recordkeeping requirements of Regulation Part 574.

Regulation Part 574 became effective May 22, 1971, for tires manufactured on and after that date.

ID: nht94-4.55

Open

TYPE: INTERPRETATION-NHTSA

DATE: October 18, 1994

FROM: Jerry G. Sullivan, P.E. -- The Braun Corporation

TO: Mary Versailles -- NHTSA Office of Chief Council

TITLE: NONE

ATTACHMT: Attached to 1/9/95 letter from Philip R. Recht to Jerry G. Sullivan (A43; Std. 217)

TEXT: Dear Mary,

I am writing for a clarification to FMVSS 217. For non-school buses, GVWR less than 10,000 lbs, can the driver side front door area be used to help meet the unobstructed openings requirement? [Ref: 55.2.2(c) Doors]

I appreciate your assistance in this matter.

Sincerely

ID: nht72-3.3

Open

DATE: 02/04/72

FROM: CHARLES A. BAKER FOR E.T. DRIVER -- NHTSA

TO: Enterprise Sky Park

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of January 20, 1972, regarding standards for retreaded automobile and truck tires.

Federal motor vehicle safety standards do not apply to aircraft or aircraft equipment.

Standard No. 117 entitled "Retreaded Pneumatic Tires - Passenger Cars," does not apply to the retreading of aircraft tires and does not supersede Advisory Circular 43.13-1. A copy of the standard is enclosed.

We do not have a safety standard for retreaded truck tires at this time.

ID: nht92-5.24

Open

DATE: July 9, 1992

FROM: Tilman (Tilghman) Spingler -- Robert Bosch GmbH

TO: Paul Jackson Rice -- Chief Counsel, NHTSA Administration

TITLE: Request for Interpretation

ATTACHMT: Attached to letter dated 8/3/92 from Paul J. Rice to Tilghman (Tilman) Spingler (A39; Std. 108)

TEXT:

FMVSS 108 requires for Replaceable Bulb Headlamps a vertical aim range of > +/- 4 degrees and a horizontal aim range of > +/- 2.3 degrees. Does this mean that a headlamp has to meet both ranges in addition, i.e. 2.5 degrees horizontal at a full range of 4 degrees vertical and vice-versa? Would it be possible to give me a "quick" answer by fax?

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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