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 |
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ID: nht68-2.36OpenDATE: 10/11/68 FROM: AUTHOR UNAVAILABLE; Clue D. Ferguson; NHTSA TO: Tejas Campers TITLE: FMVSS INTERPRETATION TEXT: Thank you for your letter of August 19, 1968, concerning glazing and lighting requirements in campers. The amendment to Standard No. 205 to which you refer, Docket No. 23, is enclosed along with a copy of FHWA Ruling 68-1. The amendment does not allow AS2 tempered glass to be placed in forward facing windows of campers. Forward facing windows of campers must be AS1, AS2 laminated that meets the requirements of test no. 26 of ASA Standard Z26.1 - 1966, or AS3 laminated that meets the requirements of test no. 26 of ASA Standard Z26.1 - 1966. Rigid plastics may be used in other windows. With respect to your question on vehicle lighting requirements, enclosed is a copy of Federal Motor Vehicle Safety Standard No. 108, effective January 1, 1969. You will note from the standard that clearance lamps are not required on vehicles less than 80 inches in overall width. The specified requirements for side marker lamps and side reflex reflectors on vehicles of less than 80 inches in overall width are contained in paragraphs S3.1.1.6 and S3.1.1.8 and Tables III and IV of Standard No 108. I have had your name added to our mailing list for all rulemakings related to multipurpose passenger vehicles and trailers and I have also enclosed information on subscribing to the Federal Register should you so desire. |
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ID: nht68-3.46OpenDATE: 07/31/68 FROM: AUTHOR UNAVAILABLE; J. R. O'Gorman; NHTSA TO: Associazione Nazionale Fra Industrie Automobilistiche TITLE: FMVSS INTERPRETATION TEXT: Thank you for your letter of June 3 to the National Highway Safety Bureau asking "whether the solution given in the enclosed drawing N. 591-1559 of Ferrari is in line with the requirements" of Federal motor vehicle safety standard No. 211. This standard states that "wheel nuts, hub caps, and wheel discs for use on passenger cars . . . shall not incorporate winged projections". The Ferrari plan appears to incorporate such a projection, even though it is recessed. Accordingly the proposed solution by Ferrari does not meet the requirements of Federal standard No. 211. ASSOCIAZIONE NAZIONALE FRA INDUSTRIE AUTOMOBILISTICHE U.S. Department of Transportation Federal Highway Administration National Highway Safety Bureau June 3 1968 Motor Vehicle Safety Standard n. 211 Reference is made to your letter of December 21st 1967 and we wish to thank you very much for the explanations about the standard N. 211. Further we would appreciate it very much your letting us know whether the solution given in the enclosed drawing N. 591-1559 of Ferrari is in line with the requirements concerning "wheel nuts, hub caps and wheel discs". Thanking you in advance, we remain Faithfully Yours, (Illegible Word) Direttore (Francesco Palazzi) |
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ID: nht68-3.5OpenDATE: 12/31/68 FROM: AUTHOR UNAVAILABLE; R. M. O'Mahoney; NHTSA TO: Brixtax (London) Ltd. TITLE: FMVSS INTERPRETATION TEXT: This is in reply to your letter of December 9, 1968, in which you inquire about the certification responsibilities of equipment manufacturers under the National Traffic and Motor Vehicle Safety Act of 1966. You state that it is your understanding that a vehicle manufacturer has the responsibility to certify the entire vehicle, including equipment that is produced by other manufacturers and covered by Federal safety standards, as complying with the applicable standards, and that the basis on which that manufacturer satisfies himself that equipment from suppliers conforms to the standards is a matter of his own discretion. I consider that statement to be essentially correct, with the caveat that the manufacturer must be able to show, under @ 108(b)(2) of the Act, that "he did not have reason to know in the exercise of due care" that any included equipment was nonconforming. What constitutes "due care" must be determined in light of all the circumstances of a particular case. You are also correct in your understanding that approval by the States has no relevance to the question of compliance with this Federal law. Finally, regardless of certification requirements all equipment must conform to applicable standards, and certification by the equipment manufacturer is required if the equipment is ultimately sold in the aftermarket. I am pleased to be of assistance. |
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ID: nht69-1.12OpenDATE: 03/16/69 FROM: AUTHOR UNAVAILABLE; Robert M. O'Mahoney; NHTSA TO: Corporation Commission of Oaklahoma TITLE: FMVSS INTERPRETATION TEXT: This is in reply to your letter of April 15, 1969, in which you inquire about Federal regulation of brake fluid. Brake fluid performance is regulated under the National Traffic and Motor Vehicle Safety Act by Federal Motor Vehicle Safety Standard No. 116. Copies of the Act and the current standards are enclosed. Under the Vehicle Safety/Act, manufacturers of motor vehicles and equipment (including brake fluid) that are covered by standards are fully responsible for ensuring that all of their products conform to the standards. The National Highway Safety Bureau conducts conformity tests of vehicles and equipment, either through its own personnel and facilities or under contract with other public or private testing organizations, but these are for enforcement purposes only. The Bureau is conducting a continuing series of tests on brake fluid, that has included samples from a majority of the major manufacturers, and will include the remainder is the near future. If you need more detailed information concerning this testing program, I suggest that you contact Mr. Francis Armstrong, Director, Office of Performance Analysis, National Highway Safety Bureau, Federal Highway Administration, Washington, D.C. 20591. In answer to your Final question, Standard No. 116 applies to all brake fluid manufactured or sold in the United States, and is not Limited to that sold by automobile manufacturers or distributors. |
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ID: nht70-2.30OpenDATE: 10/19/70 FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA TO: Department of California Highway Patrol TITLE: FMVSS INTERPRETATION TEXT: By letter of October 1, 1970, you asked for the opinion of this office as to whether the State of California, in specifying approval procedures for seat belts to be sold within the State, must require seat belt manufacturers to produce data showing that they have performed the exact tests specified in Federal Motor Vehicle Safety Standard No. 209. The Federal motor vehicle safety standards are not instructions for, or descriptions of, manufacturer tests, nor do they specify types and numbers of tests. They are statements of requirements that each vehicle or item of equipment must meet when tested by the Bureau. Manufacturers are required to exercise due care to ensure that their vehicles will meet the standards if tested by the Bureau, and they are at their own discretion in devising an appropriate testing program for that purpose. If a seat belt manufacturer presents data of tests conducted on webbing taken from rolls, rather than from individual assemblies, and if you are satisfied that such data demonstrates that the webbing would comply with Standard No. 209 when tested according to the procedures of that standard, you may, in our opinion, accept such data for purposes of State approval. I trust that your question has been adequately answered. If you need further clarification we will be glad to provide it. |
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ID: nht70-2.33OpenDATE: 10/29/70 FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA TO: Juno Industries, Inc. TITLE: FMVSS INTERPRETATION TEXT: Your letter of August 26, 1970, concerning the compliance of your cut-van motor home with Federal Motor Vehicle Safety Standard No. 206 - Door Locks and Door Retention Components, has been forwarded to this office for reply. You state that the door in the camper body is located so that no portion of a manikin in any designated seating position would project into the door opening in the side view. If, as it appears, you are correct, the door locks and door retention components on that door are not required to comply with Standard No. 206. You also state that you believe that the doors on the cab comply with Standard No. 206. As a manufacturer of multipurpose passenger vehicles, you are responsible under the National Traffic and Motor Vehicle Safety Act of 1966 for the compliance of the cab doors with Standard No. 206. Although the van may have been manufactured as a truck, it must, when subsequently converted to a multipurpose passenger vehicle, comply with all multipurpose passenger vehicle standards in effect on the date of manufacturer of your motor home. Therefore, you should(Illegible Word) either from the van manufacturer or by your own tests, that the cab doors comply with Standard No. 206. Please let us know if we can be of further assistance. |
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ID: nht71-2.10OpenDATE: 03/01/71 FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA TO: Bolt Beranek and Newman, Inc. TITLE: FMVSS INTERPRETATION TEXT: This is in reply to your letter of February 5, 1971, concerning certification of child seating systems. Your letter asks whether the statement, "This (child seating system) conforms to all applicable Federal Motor Vehicle Safety Standards in effect on the date of manufacture shown above," or alternatively the symbol "DOT," may be used to certify that a child seating system complies with Standard No. 213. You also ask whether the certification statement may be placed on the label required on the child seat pursuant to S4.1 of the standard. The statement that you submit is an adequate certification statement. Furthermore, this statement or a similar statement may be placed on the label required pursuant to S4.1 of the standard, as the certification would therefore be "in the form of a label or tag" on the item of motor vehicle equipment as specified in section 114 of the National Traffic and Motor Vehicle Safety Act (15 U.S.C. @ 1403). With reference to use of the symbol "DOT" for certifying child seating systems, while this symbol is presently used by manufacturers to certify other items of motor vehicle equipment, its use as such is only pursuant to specific provisions of the standards. We cannot approve of its use for child seating systems without prior rulemaking. WE ARE PLEASED TO BE OF ASSISTANCE. |
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ID: nht71-2.36OpenDATE: 04/30/71 FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA TO: Hartman Mfg. Co. TITLE: FMVSS INTERPRETATION TEXT: This is in reply to your letter of April 9, 1971 concerning certain provisions of Motor Vehicle Safety Standard No. 213, "Child Seating Systems." In your letter you ask whether S4.4 of the standard requires the child seating system itself to be restrained by the seat belt assembly. You state that S4.5.1 indicates to you that the vehicle seat belt assembly is employed to restrain both the child and the seating system, and request that this issue be clarified. S4.4(a) of the standard requires each child seating system, when installed as the manufacturer directs, to be restrained by the vehicle seat belt assembly. The vehicle seat belt assembly may also be used to directly restrain the child, but it is not required to do so. When it is used for this purpose, however, it must distribute the restraint forces as specified by S4.5.1 of the standard. The statement in the preamble of the notice of March 23, 1970 to which you refer describes the scope of the standard. This statement means that any device for seating children in a motor vehicle that is designed to utilize the vehicle restraint system or provides restraint by itself, or both, is a "child seating system" and must comply with all the requirements of the standard. We are pleased to be of assistance. |
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ID: nht72-3.23OpenDATE: 07/28/72 FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA TO: Resources Applications, Designs & Control, Incorporated TITLE: FMVSS INTERPRETATION TEXT: This is in response to your letter of July 21, 1972 requesting a determination as to the applicability of Federal Motor Vehicle Safety Standard No. 206, Door Locks and Door Retention Components, to (Illegible Words) equipment manufactured for installation on truck tractors. An amendment to Standard No. 206 was issued in January 1972 (37 F.R. 284), which stated that the requirements of the Standard are applicable to any side door leading directly into a passenger compartment containing one or more seating accommodations. From the information and photographs you provided, it appears that although the (Illegible Words) equipment is a passenger compartment, it is designed as a completely separate unit not containing any seating accommodations, and would therefore be exempt from the requirements of Standard No. 206. It should be noted, however, that is not sleeper berth equipment is installed in such a way that it is (Illegible Word) to the truck cab and can be (Illegible Word) by the driver from within the cab, than any side doors on the sleeper berth equipment would be side door leading into a passenger compartment (the cab) containing seating accommodation and they would have to meet the requirements of the Standard. For your information, I am enclosing a copy of this (Illegible Words) to Standard No. 206. |
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ID: nht71-4.13OpenDATE: 09/18/71 FROM: AUTHOR UNAVAILABLE; L. R. Schneider; NHTSA TO: Meiji Rubber & Chemical Company, Ltd. TITLE: FMVSS INTERPRETATION TEXT: RE: HYDRAULIC BRAKE HOSE ASSEMBLIES This is in reply to your letter of September 3 asking questions about compliance of hydraulic brake hose assemblies with Federal Motor Vehicle Safety Standard No. 106. With respect to your first two questions, the National Highway Traffic Safety Administration does not require that you demonstrate compliance with Standard No. 106 prior to supplying Japanese car manufacturers with brake hose assemblies to be installed on cars intended for export to the United States. If the Japanese vehicle manufacturers request proof of compliance from you (apparently in the form of a certification from the Commonwealth of Pennsylvania based upon test reports from only one of two test laboratories) such a request is solely a business matter between you and the vehicle manufacturer. Your third question points out that proposed Standard No. 106 (Docket No. 1-5, Notice 7) would eliminate the specification of braid material for hydraulic brake hoses and asks whether you may implement this "revision" at the present time. Notice 7 is a proposal only, and the current requirements specifying braid material remain in effect until a formal amendment of Standard No. 106 occurs. The brake hose manufacturer's code number, the subject of your fourth question, is also a proposal which may or may not be adopted in the final rule. |
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.