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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 11321 - 11330 of 16490
Interpretations Date

ID: mills.ztv

Open

    Mr. Robert G. Mills
    Supervisor, Homologation and Publications
    Triumph Motorcycles, Ltd.
    Jacknell Road
    Hinckley, Leicestershire LE10 3BS
    United Kingdom

    Dear Mr. Mills:

    This is in reply to your fax of August 22, 2003, with reference to paragraph S7.9.6.2 of Federal Motor Vehicle Safety Standard No. 108.

    You described a single motorcycle headlamp "with two separate illuminating compartments, one of which contains the lower beam and the other the upper beam." The projectors providing each beam would be mounted at the same height and symmetrically disposed around the vertical centerline of the motorcycle. When only the lower beam is activated, the lighting array would be asymmetric; however, the lower beam remains activated when the upper beam is activated, resulting in a symmetric lighting display. You are aware of our 1994 and 1995 interpretations to Jeffrey Shetler of Kawasaki which, in your view, "clearly indicate that an asymmetric lower beam coming from a single headlamp is not considered to comply with the standard." You have asked us to reconsider these interpretations in view of the fact that paragraph S7.9.6.2(c) permits asymmetrical lighting in a two-headlamp motorcycle headlighting system when an upper beam headlamp and a lower beam headlamp are mounted on either side of the vertical centerline.

    Our previous letters to Mr. Shetler were based upon Table IV of Standard No. 108 as in effect in 1994 and 1995. Table IV stated that a motorcycle headlamp must be located "On the front, on the vertical centerline, except that if two are used they shall be symmetrically disposed about the vertical centerline." The headlamp described by Mr. Shetler would be mounted on the vertical centerline, but, as we informed him, "the beams provided by the headlamp are located on either side of the centerline and are therefore asymmetrical in relation to the centerline of the motorcycle when either beam is activated." We did not consider this a configuration that met Table IV.

    However, since the time of those earlier interpretation letters, relevant changes have been made to FMVSS No. 108. Today, as a result of a 1998 final rule (63 FR 42582, August 10, 1998) that specifically allows asymmetrical headlamp beams on motorcycles, a single-headlamp beam configuration as you have described would comply with the requirements of S7.9.6.2(a). Furthermore, in this case, we note that all compartments that are wired to illuminate in the upper beam mode must be illuminated when determining compliance with the upper beam photometry requirements.

    If you have further questions, you may refer them to Mr. Eric Stas of this office (202-366-5263).

    Sincerely,

    Jacqueline Glassman
    Chief Counsel

    ref:108
    d.9/26/03

2003

ID: nht95-1.84

Open

TYPE: INTERPRETATION-NHTSA

DATE: March 2, 1995

FROM: Philip R. Recht -- Chief Counsel, NHTSA

TO: Steve Brooks -- General Manager, IAD West Coast, Inc.

TITLE: None

ATTACHMT: ATTACHED TO 11/1/94 LETTER FROM STEVE BROOKS TO JOHN WOMACK (OCC 10473)

TEXT: This replies to your letter of November 1, 1994, to John Womack, former Acting Chief Counsel. IAD West Coast ("IAD") is converting a Subaru panel van from internal combustion to electric drive. The vehicle is currently a prototype but "will be modified in the state of California, to OEM build standards." You have asked for help "with the definition of crash testing for front and side impact for the vehicle for current and future production, also with the requirement for dual air bags if necessary."

Because we did not understand what you meant by "definition", Taylor Vinson of this office spoke with you on January 24, 1995. He learned that IAD is engineering the prototype for production by another company, and that your question related to the exte nt of crash testing that is required before production. He then explained to you that there is no legal requirement that prototype vehicles be crashed, but that production vehicles must conform with the performance requirements of standards with crash d emonstration procedures, and that the manufacturer's certification of compliance may be based upon good faith surrogates to crash testing such as computer simulation, engineering studies, and mathematical calculations. The Department of Transportation, however, tests in the manner specified in a standard, and if there is a test failure, will ask the manufacturer to supply the data upon which it based its certification.

Your letter also asks about "the requirement for dual air bags if necessary in the future." Manufacturers of light trucks will be required to install dual air bags in not less than 80% of vehicles produced between September 1, 1997, and September 1, 1998 , and in 100% of production from September 1, 1998, on.

Finally, you have asked whether we have information on approach and departure angles. These are not part of the FMVSS, and are established by the manufacturer in designing a vehicle.

I hope that this answers your questions.

ID: nht89-3.46

Open

TYPE: INTERPRETATION-NHTSA

DATE: 11/28/89

FROM: STEPHEN P. WOOD -- NHTSA ACTING CHIEF COUNSEL

TO: WILLIAM E. ALKIRE -- CEO, BRAKELIGHT ENHANCER, INC.

TITLE: NONE

ATTACHMT: LETTER DATED 08/24/89 FROM WILLIAM E. ALKIRE -- BRAKELIGHT ENHANCER, TO TAYLOR VINSON -- NHTSA, RE BRAKELIGHT ENHANCER; OCC 3876; SENATE BILL NO 684, CHAPTER 410; APPROVED 07/27/83; SENATE BILL NO 1317, AMENDED IN SENATE MARCH 8, 1982; INTRODUC ED BY SENATOR JOHNSON ON 01/07/1982

TEXT: Dear Mr. Alkire:

This is in response to your letter of August 24, 1989, in care of Taylor Vinson of this Office, asking for our comments on your "Brake Light Enhancer". This device flashes the stop lamps of a vehicle three times within the first two seconds after actuat ion of the stop lamp system, the lamps remaining illuminated thereafter.

Our comments on your device are restricted to its acceptability under the Federal regulatory scheme as either original or aftermarket equipment.

The Federal motor vehicle safety standard applicable to lighting equipment on new vehicles is Standard No. 108. This standard must be met when the vehicle is manufactured, and when it is sold to its first purchaser (i.e., dealer-installed equipment must not affect compliance of the vehicle with the safety standards). Section S5.510(e) of Standard No. 108 requires stop lamps to be wired to be steady burning in use, and your device's initial cycle of three flashes in two seconds would create a noncomplia nce with this requirement. Accordingly, your device is not permissible as an item of original equipment.

There is no aftermarket Federal standard applicable to your device. Equipment intended for vehicles in use are subject to the restriction of the National Traffic and Motor Vehicle Safety Act that they may not render inoperative, in whole or in part, equ ipment installed in accordance with a Federal motor vehicle safety standard, if they are installed by a person other than the vehicle owner. In our view, if a modification creates a noncompliance with a standard that applies to a new motor vehicle, it is the equivalent of creating a partial inoperability of original safety equipment when that modification is performed on a motor vehicle in use. Installation of the Brake Light Enhancer by a person other than the vehicle owner would have this effect, and thus would be subject to the prohibition of the Act.

Use of the device is also subject to the laws of the various States in which the device will be sold and operated. Although California may permit its use, per Calif. Senate Bill 1317 that you enclosed, other States may not. We are unable to advise on State laws, and recommend that you write the American Association of Motor Vehicle Administrators for an opinion. Its address is 4600 Wilson Boulevard, Arlington, VA 22203.

Sincerely,

ID: 0473a

Open

Mr. Steve Brooks
General Manager
IAD West Coast, Inc.
5761 McFadden Ave.
Huntington Beach, CA 92649

Dear Mr. Brooks:

This replies to your letter of November 1, 1994, to John Womack, former Acting Chief Counsel. IAD West Coast ("IAD") is converting a Subaru panel van from internal combustion to electric drive. The vehicle is currently a prototype but "will be modified in the state of California, to OEM build standards." You have asked for help "with the definition of crash testing for front and side impact for the vehicle for current and future production, also with the requirement for dual air bags if necessary."

Because we did not understand what you meant by "definition", Taylor Vinson of this Office spoke with you on January 24, 1995. He learned that IAD is engineering the prototype for production by another company, and that your question related to the extent of crash testing that is required before production. He then explained to you that there is no legal requirement that prototype vehicles be crashed, but that production vehicles must conform with the performance requirements of standards with crash demonstration procedures, and that the manufacturer's certification of compliance may be based upon good faith surrogates to crash testing such as computer simulation, engineering studies, and mathematical calculations. The Department of Transportation, however, tests in the manner specified in a standard, and if there is a test failure, will ask the manufacturer to supply the data upon which it based its certification.

Your letter also asks about "the requirement for dual air bags if necessary in the future." Manufacturers of light trucks will be required to install dual air bags in not less than 80% of vehicles produced between September 1, 1997, and September 1, 1998, and in 100% of production from September 1, 1998, on.

Finally, you have asked whether we have information on approach and departure angles. These are not part of the FMVSS, and are established by the manufacturer in designing a vehicle.

I hope that this answers your questions.

Sincerely,

Philip R. Recht Chief Counsel ref:208 d:3/2/95

1995

ID: nht90-4.23

Open

TYPE: Interpretation-NHTSA

DATE: September 26, 1990

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: Hiroshi Kato -- Vice President, Mitsubishi Motors America, Inc.

TITLE: None

ATTACHMT: Attached to letter dated 9-4-90 from H. Kato to P.J. Rice (OCC 5193); Also attached to drawing of proposed illumination on rear panel garnish and photo of 1988 Pontiac Fiero (graphics omitted)

TEXT:

This is in reply to your letter of September 4, 1990, asking for an interpretation of paragraph S5.1.3 of Standard No. 108 with respect to two of Mitsubishi's contemplated rear lighting plans.

In the first plan, the rear garnish panel located between the lamps that are mounted at the right and left extremities of the car would be dark but the word "Mitsubishi" in the center would be illuminated. In the second plan, the panel would be illumina ted as a supplemental taillamp, and the word would not. You ask if either plan would create an "impairment" of the required lighting equipment, within the prohibition of S5.1.3.

Judging by the photograph of the Pontiac Fiero that you enclosed, which featured a design similar to your first plan, it does not appear that this plan would create an impairment.

We note that the backup lamp is located in the garnish panel, approximately 15 mm from the word "Mitsubishi", and this raises a question with respect to the second plan. When the taillamps are illuminated, so that there is a broad sweep of red light acr oss the rear of the car, we would be concerned that the backup lamps in the garnish panel might not be readily perceived when activated. We would also be concerned that the illuminated panel might detract from the effectiveness of the stop lamps when th ey are activated. To ensure that the lighted panel creates no impairment of either the stop lamps or the backup lamps, it might be advisable to design it with an intensity that is lower than that of the adjacent taillamps.

The determination of impairment is to be made by the vehicle manufacturer in its certification that the vehicle complies with all applicable Federal motor vehicle safety standards. Unless that determination appears clearly erroneous, NHTSA will not ques tion it.

I hope that this answers your question.

ID: 2668y

Open

Mr. Hiroshi Kato
Vice President
Mitsubishi Motors America, Inc.
Suite 1960
3000 Town Center
Southfield MI 48075

Dear Mr. Kato:

This is in reply to your letter of September 4, l990, asking for an interpretation of paragraph S5.1.3 of Standard No. l08 with respect to two of Mitsubishi's contemplated rear lighting plans.

In the first plan, the rear garnish panel located between the lamps that are mounted at the right and left extremities of the car would be dark but the word "Mitsubishi" in the center would be illuminated. In the second plan, the panel would be illuminated as a supplemental taillamp, and the word would not. You ask if either plan would create an "impairment" of the required lighting equipment, within the prohibition of S5.1.3.

Judging by the photograph of the Pontiac Fiero that you enclosed, which featured a design similar to your first plan, it does not appear that this plan would create an impairment.

We note that the backup lamp is located in the garnish panel, approximately l5 mm from the word "Mitsubishi", and this raises a question with respect to the second plan. When the taillamps are illuminated, so that there is a broad sweep of red light across the rear of the car, we would be concerned that the backup lamps in the garnish panel might not be readily perceived when activated. We would also be concerned that the illuminated panel might detract from the effectiveness of the stop lamps when they are activated. To ensure that the lighted panel creates no impairment of either the stop lamps or the backup lamps, it might be advisable to design it with an intensity that is lower than that of the adjacent taillamps.

The determination of impairment is to be made by the vehicle manufacturer in its certification that the vehicle complies with all applicable Federal motor vehicle safety standards. Unless that determination appears clearly erroneous, NHTSA will not question it.

I hope that this answers your question.

Sincerely,

Paul Jackson Rice Chief Counsel

ref:l08 d:9/26/90

1990

ID: 18327.ztv

Open

Mr. John D. Evans
Vice President Engineering
The Knapheide Manufacturing Company
P.O. Box 7140
Quincy, IL 62305-7140

Dear Mr. Evans:

This is in reply to your letter of June 29, 1998, asking for an interpretation of a note to Federal Motor Vehicle Safety Standard No. 108 Lamps, Reflective Devices, and Associated Equipment.

Standard No. 108 and some of the SAE standards that it incorporates by reference distinguish between vehicles with an overall width of 80 inches or more, and those of lesser width. A note to Standard No. 108 defines "overall width" as the nominal design dimension of the widest part of the vehicle, but excludes certain items including "flexible fender extensions." You have asked whether this term would apply to "a rubber fenderette that is attached to a steel body fender panel." You have also asked whether a "fender design with an integral flare which would be made of a flexible material" and is "easily deformable by finger pressure" would also qualify as a "flexible fender extension."

Although the term "flexible fender extension" has been in the note since 1967 (published at 32 FR 8803), it is not specifically defined. We can find only one instance in which we have interpreted the term. In a letter of May 22, 1997, to Ben Reginella, we informed him that the "painted flexible flares" that he was developing for a Dodge truck were "flexible fender extensions" within the meaning of the term. However, we did not explain how we reached that conclusion. With respect to your "fender design with an integral flare which would be made of flexible material," and which is "easily deformable by finger pressure," in our view, this would not be included in the calculation of "overall width."

We are less certain about "a rubber fenderette." While this might be a "fender extension," its flexibility would appear to depend upon the degree of the hardness of the rubber. It would be a "flexible fender extension" if it, too, is easily deformable by finger pressure.

If you have any questions, you may call Taylor Vinson of this Office (202-366-5263).

Sincerely,
Frank Seales, Jr.
Chief Counsel
ref:108
d.8/17/98

1998

ID: nht76-5.30

Open

DATE: 04/12/76

FROM: AUTHOR UNAVAILABLE; Stephen P. Wood; NHTSA

TO: Cameo Industries

COPYEE: STEPHEN P. WOOD FOR FRANK A. BERNDT -- NHTSA

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your March 17, 1976, letter concerning reporting forms for the mini motor homes that you contemplate building.

The National Highway Traffic Safety Administration (NHTSA) issues Federal motor vehicle safety standards to which motor vehicles must conform. In addition, the agency requires that the manufacturer certify that the vehicles as completed comply with applicable safety standards. A pamphlet summarizing the Federal motor vehicle safety standards is enclosed, along with a copy of the regulations governing vehicle certification. The safety standards themselves are set forth in their entirety in Part 571 of Title 49 of the Code of Federal Regulations.

The NHTSA also investigates safety-related defects and noncompliances with safety standards in motor vehicles and items of motor vehicle equipment. If the agency or the manufacturer determines that a safety-related defect or noncompliance exists, the manufacturer is obligated to notify the vehicle owners and remedy the problem without charge. A copy of the provisions of the National Traffic and Motor Vehicle Safety Act of 1966, as amended, which deal with the responsibilities of manufacturers for safety-related defects and noncompliances in their motor vehicles or items of vehicle equipment (15 U.S.C. @@ 1411-1420) is also enclosed. Further, 49 CFR Part 573, Defect Reports, requires the submission to the NHTSA of information reports concerning defects. A copy of this regulation is enclosed. No particular reporting form is required.

In addition, a new manufacturer of motor vehicles is required by 49 CFR Part 566, Manufacturer Identification, to submit certain information to the NHTSA not more than 30 days after he begins manufacture. A copy of this regulation is also enclosed.

SINCERELY,

To: Office of Chief Counsel NHTSA

From: Cameo Industries

Subject: Motor home reports

MESSAGE:

We are contemplating building mini motor homes and are therefore interested in the reporting forms to be made on these vehicles. We would like to know what kind of monthly, quarterly etc. forms need to be filled out. Could your office send us a list of these forms? Thank you very much for your help on this matter.

Date 3/17/76

Signed Sam F Lancaster President

ID: time.replcepart.Pollak.12-03

Open

    David G. Pollok, Esq.
    Kirkpatrick & Lockhart LLP
    599 Lexington Avenue
    New York, NY 10022-6030

    Dear Mr. Pollak:

    This responds to your recent request for an interpretation of the provisions of the National Traffic & Motor Vehicle Safety Act of 1966, as amended (Safety Act). Specifically, you asked whether Federal law obliges an automobile manufacturer to continue producing and/or supplying replacement parts for a vehicle model that has not been manufactured or distributed in 10 years, and, if so, for how long. In a subsequent telephone conversation with Enid Rubenstein of my staff, you stated that the vehicles in question have never been recalled pursuant to the Safety Act to correct a safety-related defect or non-compliance with a Federal Motor Vehicle Safety Standard.

    There is no provision in the Safety Act or in any of our safety standards or other regulations that requires a manufacturer to make replacement parts available for any particular period of time, or, for that matter, at all. However, under 49 U.S.C. 30118-30119, vehicle manufacturers are required to provide notification of safety-related defects or noncompliances with safety standards to owners, purchasers, and dealers for an unlimited period of time. Also, under 49 U.S.C. 30120, if either a manufacturer or this agency decides, within 10 years of the date of sale of the vehicle to the first purchaser, that a motor vehicle contains a safety-related defect or fails to comply with a Federal motor vehicle safety standard, the manufacturer is required to provide a free remedy for the safety-related defect or noncompliance. These remedies may include the repair, replacement or repurchase of the affected vehicles.

    Although your clients vehicles apparently are beyond the age at which a free repair for a safety-related defect or noncompliance could be required, your client may wish to consider the issue of the ability to provide repairs in deciding whether to continue to make available replacement parts for its vehicles. We understand that some vehicle manufacturers do make various replacement parts available for a considerable period of time.

    Sincerely,

    Jacqueline Glassman
    Chief Counsel

    ref:VSA
    d.12/19/04

2004

ID: nht75-3.29

Open

DATE: 10/22/75

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Koher Company

COPYEE: SENATOR PROXMIRE

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your letter of September 29, 1975, to Senator Proxmire, concerning the regulations governing the production of motor vehicles, a copy of which was referred to this office.

The National Highway Traffic Safety Administration (NHTSA) issues Federal motor vehicle safety standards to which motor vehicles must conform. In addition, the agency requires that the manufacturer certify that the vehicle as completed complies with applicable safety standards. A pamphlet summarizing the Federal motor vehicle safety standards is enclosed, along with a copy of the regulations governing vehicle certification. The safety standards themselves are set forth in their entirety in Part 571 of Volume 49 of the Code of Federal Regulations.

The NHTSA also investigates safety-related defects and noncompliances with safety standards in motor vehicles and items of motor vehicle equipment. If the agency or the manufacturer determine that a safety-related defect or noncompliance exists, the manufacturer is obligated to notify the vehicle owners and remedy the problem without charge. A copy of the provisions of the National Traffic and Motor Vehicle Safety Act of 1966, as amended, which deal with the responsibilities of manufacturers for safety-related defects and noncompliances in their motor vehicles or item of vehicle equipment (15 U.S.C. @ 1411-1420) is also enclosed.

If you have any questions concerning a specific regulation or standard, please write.

United States Senate 10/7/75

To ensure proper handling please return all correspondence TO THE ATTENTION OF:

Geri Rosen

Respectfully referred to: Cong. Liaison DOT

Please respond to the attached inquiry in duplicate and return the enclosure. Thank you for your cooperation. (Illegible Word) U.S.S.

September 24, 1975

DEAR SENATOR:

Kohler Co. is investigating what would be involved in going into production on a very small, very fuel efficient, low-cost urban car suitable for shopping and commuting. We know there are several government agencies that have regulations controlling how you build a vehicle but we do not know what those regulations are or even what agencies we would have to contact. It is vitally important that we know all the regulations and wondered if you know some way we can obtain a copy of all the regulations from all the controlling bureaus. We would certainly appreciate your help in this quest.

YOURS TRULY,

Daniel J. Wahlen Director - Engines Engineering -- KOHLER CO.

Senator William Proxmire

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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