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
| Interpretations | Date |
|---|---|
| search results table | |
ID: aiam1030OpenMr. Bill B. Wiggins, Wiggins & Christian, 602 First Federal Building, Post Office Box 994, Fort Smith, AR 72901; Mr. Bill B. Wiggins Wiggins & Christian 602 First Federal Building Post Office Box 994 Fort Smith AR 72901; Dear Mr. Wiggins: This is in response to your letter of February 27, 1973, concerning th application of the new Federal Odometer Disclosure Requirements to transfers between dealers.; The Federal requirements apply, with certain exceptions, to eac transfer of ownership of a motor vehicle. Some types of vehicles, such as heavy trucks and antique vehicles, are exempt. Passenger cars and lighter vehicles, however, are exempted only in the case of transfers of *new* vehicles from a manufacturer or a distributor to a dealer or from one dealer to another. The transfer of a *used* car or light truck, whether from dealer to dealer, dealer to wholesaler, or dealer to customer, must be accompanied by a disclosure statement.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam4662OpenMr. William E. Alkire CEO, Brakelight Enhancer, Inc. 1010 Rancheros Drive San Marcos, CA 92069; Mr. William E. Alkire CEO Brakelight Enhancer Inc. 1010 Rancheros Drive San Marcos CA 92069; Dear Mr. Alkire: This is in response to your letter of August 24, l989 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 actuation 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 S5.5.10(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 noncompliance 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, equipment 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 orignial 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, Stephen P. Wood Acting Chief Counsel; |
|
ID: aiam4398OpenMr. Hiroshi Kato, Assistant Vice President, Technical, MMC Services, Inc., 3000 Town Center, Suite 1960, Southfield, MI 48075; Mr. Hiroshi Kato Assistant Vice President Technical MMC Services Inc. 3000 Town Center Suite 1960 Southfield MI 48075; Dear Mr. Kato: This responds to your letter dated August 3, 1987, in which you sough my confirmation of a previous interpretation I sent to you. The issue is the classification of a new mini-van for the purposes of our safety and bumper standards. I stated in a July 28, 1987 interpretation to your company that, based on the information you had provided, this new mini-van could be classified as a multipurpose passenger vehicle, because it is constructed on a truck chassis. My conclusion that the mini-van's chassis could be considered a truck chassis was based on information you had provided showing that the chassis design and construction was more suitable for heavy duty commercial operation than a conventional passenger car chassis.; In response to this letter, you sent me another letter dated August 3 1987, in which you stated that my previous interpretation may have been based on the erroneous belief that you were going to introduce a cargo version of this mini-van in to the United States, and that this cargo version would have a chassis that was substantially reinforced as compared with the chassis on a passenger version of this mini-van.; My previous interpretation was based on the fact that the mini-van yo will introduce into the United States is built on a truck chassis. My conclusion that the chassis can properly be characterized as a truck chassis was based on the facts that the chassis has a heavier-duty rear suspension and longitudinal members and a 25 percent higher gross vehicle weight rating than the sedan version of this vehicle. Assuming that these understandings are accurate, because nothing in your August 3 letter indicates they were inaccurate, the agency's position was accurately expressed in my July 28, 1987 letter to your company.; Sincerely, Erika Z. Jones, Chief Counsel |
|
ID: aiam1460OpenMr. Charles E. Park, President, Intermodal Services, Inc., P.O. Box 111, 4 Lavista - Perimeter Park - Suite 130, Tucker, GA 30084; Mr. Charles E. Park President Intermodal Services Inc. P.O. Box 111 4 Lavista - Perimeter Park - Suite 130 Tucker GA 30084; Dear Mr. Park: This responds to your April 8, 1974, request for a waiver from Standar 121, *Air brake systems*, to permit the manufacturer of semi-trailers which do not comply with the standard after its effective date.; Our authority to enforce standards under S108(a)(1) of the Nationa Traffic and Motor Vehicle Safety Act of 1966 prohibits the sale of a vehicle which does not comply with applicable standards. We are unable to permit by regulation what is prohibited by this section of the law.; We do have under consideration petitions to delay the effective date o Standard 121 as it applies to trailers.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam3148OpenMr. William Shapiro, Volvo of America, Rockleigh, NJ 07647; Mr. William Shapiro Volvo of America Rockleigh NJ 07647; Dear Mr. Shapiro: This is in response to the questions that you addressed to Mr. Hug Oates over the telephone with regard to auxiliary fuel tanks. I have enclosed a copy of a letter which was sent to a company that planned to manufacture auxiliary fuel tanks for passenger cars and to do some installation. The principles enunciated in that letter are applicable to auxiliary fuel tanks intended for use in all types of motor vehicles except motor carriers in interstate commerce. If you have any further questions after reading the enclosed letter please feel free to contact Ms. Debra Weiner of my office who is familiar with the issues arising from the manufacture and use of auxiliary fuel tanks.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam1175OpenMr. Edward W. Gaylord, Vice President, Gaylord Products, Inc., 1918 Prairie Avenue, Chicago, IL 60616; Mr. Edward W. Gaylord Vice President Gaylord Products Inc. 1918 Prairie Avenue Chicago IL 60616; Dear Mr. Gaylord: This is in reply to your letter of June 26, 1973, to Mr. Vinson of thi office, enclosing the proposed Panther certification label, and asking whether it conforms to our requirements. The label is arranged as a narrow horizontal strip with two lines of type.; The label contains the required statements in the required order, an thus fulfills the requirements.; Sincerely, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam4377OpenMr. John Scott Hatt, 1215 N. Quinn Street, Apt #2, Arlington, VA 22209; Mr. John Scott Hatt 1215 N. Quinn Street Apt #2 Arlington VA 22209; Dear Mr. Hatt: This is in reply to your letter of June 8, 1987, to this agency askin about the legality of having 'a lighted sign on the side of a car door used for advertising purposes.' You have also asked whether such a sign would be a safety hazard to other drivers.; There is no Federal prohibition against installation of such a sign Its legality would be determined under local laws where a vehicle with a lighted sign would be registered and operated. You might wish to seek the advice of Arlington traffic officials and the Virginia State Police on this subject. It is not possible to say whether such a sign would be a safety hazard. Unlit advertising signs seem permissible in some areas on the sides of buses.; Sincerely, Erika Z. Jones, Chief Counsel |
|
ID: aiam3518OpenMr. David Traxler, 147 King George Way, Columbia, SC 29210; Mr. David Traxler 147 King George Way Columbia SC 29210; Dear Mr. Traxler: This is to follow-up your telephone call of October 29, 1981, askin whether any Federal motor vehicle safety standards apply to 'hatchback' door latches.; Safety Standard No. 206, *Door Locks and Door Retention Components* includes requirements for side door latches. We have enclosed a copy of that standard for your convenience.; There are no Federal motor vehicle safety standards applicable to th rear latch of a hatchback. However, even in the absence of a safety standard, the defect provisions of the National Traffic and Motor Vehicle Safety Act may be applicable. Sections 151 *et seq*. of the Act provide that manufacturers of motor vehicles and motor vehicle equipment must notify owners of vehicles and equipment with safety-related defects and remedy those defects free of charge.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam1525OpenMr. J. W. Kennebeck, Manager, Emissions, Safety & Development, Volkswagen of America, Inc., Englewood Cliffs, NJ 07632; Mr. J. W. Kennebeck Manager Emissions Safety & Development Volkswagen of America Inc. Englewood Cliffs NJ 07632; Dear Mr. Kennebeck: This responds to your May 22, 1974, question whether Volkswagen' passive belt system may be equipped with a 'comfort clip,' and whether an optional Type I lap belt may be offered in conjunction with the passive system. Your passive system consists of an upper torso restraint and, in place of a lap belt, knee padding under the dashboard.; A vehicle which satisfies Standard No. 208, *Occupant cras protection*, may be equipped, at the option of the manufacturer, with additional safety belts which conform to Standard No. 209, *Seat belt assemblies*. Additional belts, like any required belt, must conform to the S7.2 requirements for latch mechanisms.; >>>S7.2 *Latch mechanism*. A seat belt assembly installed in passenger car shall have a latch mechanism --; (a) Whose components are accessible to a seated occupant in both th stowed and operational positions,; (b) That releases both the upper torso restraint and the lap bel simultaneously, if the assembly has a lap belt and an upper torso restraint that require unlatching for release of the occupant, and; (c) That releases at a single point by a push-button action.<<< This requirement assures that the occupant crash protection provide under Standard No. 208 is not diminished by a complicated and slow series of belt latch mechanisms which could otherwise be introduced into the vehicle.; Volkswagens' passive upper torso restraint and a separate active la belt do not violate S7.2(b) in combination. Simultaneous release is required only 'if the assembly has a lap belt and an upper torso restraint that require unlatching for release of the occupant.' As described, Volkswagen's upper torso restraint does not require unlatching for release of the occupant.; With regard to our regulation of 'comfort clips', we approved the us of a clip in a March 9, 1973, letter to General Motors, to relieve belt tension in limited circumstances. A copy of that letter is enclosed. In that case, the lap belt provided could be independently and firmly adjusted to limit occupant movement, providing protection in the event of lateral and rollover crashes. Until we have further details on the functioning of the Volkswagen clips, however, which we urge you to submit, we are unable to determine whether it would conform to the adjustment requirements of S7.1.1 of Standard No. 208, *Occupant crash protection*.; Sincerely, Lawrence R. Schneider, Chief Counsel |
|
ID: aiam4727OpenMs Margaret Schmock Dept K2/ELE2 Robert Bosch GmbH Postfach 42 7410 Reutlingen W. Germany; Ms Margaret Schmock Dept K2/ELE2 Robert Bosch GmbH Postfach 42 7410 Reutlingen W. Germany; Dear Ms Schmock: This is in reply to your FAX of March 6, l990, wit respect to the relationship between Federal Motor Vehicle Safety Standard No. 108, and 'CAC Title 13, Article 9'. You have indicated that CAC requires a headlamp adjustment range in the horizontal of at least +/- 4 degrees, whereas Standard No. 108 requires a horizontal adjustment range of not less than 2.5 degrees. You have asked whether Bosch headlamps still must have an adjustment range of +/-4 degrees in the horizontal although Standard No. 108 has been changed. We understand that 'CAC' refers to 'California Administrative Code'. The effect of the preemption provisions of the National Traffic and Motor Vehicle Safety Act is to prohibit California from adopting and enforcing a minimum horizontal headlamp adjustment range greater or less than 2.5 degrees. Thus, a State requirement that a headlamp have a horizontal range of +/- 4 degrees is invalid because it differs from a corresponding Federal requirement. We are unable to answer your further questions with respect to the California code, and suggest that, for further information you write Department of Motor Vehicles, State of California, 2415 First Avenue, Sacramento, California 95818, ATTN: Mr. A. A. Pierce, Director (FAX 916-732-7854). Sincerely, Stephen P. Wood Acting Chief Counsel; |
|
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.