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 |
|---|---|
ID: nht69-2.3OpenDATE: 05/08/69 FROM: AUTHOR UNAVAILABLE; Charles A. Baker; NHTSA TO: Kentucky Manufacturing Company TITLE: FMVSS INTERPRETATION TEXT: Thank you for your letter of April 7, 1969, to Mr. Frank Turner, Federal Highway Administrator, concerning your request for a clarification of the requirements of rear lights on Drop Frame Trailers. In determining compliance with Federal Motor Vehicle Safety Standard No. 108, requirements for tail, stop, and turn signal lamps on this type of vehicle will be predicated on the normal driving, or closed tailgate, position. These lamps should therefore meet the requirements of the referenced SAE Standards in Table I and be mounted per the requirements of Table II of Standard No. 108, a copy of which is enclosed. Thank you for your interest in meeting the intent of the requirements of Standard No. 108. |
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ID: nht70-1.30OpenDATE: 01/06/70 FROM: AUTHOR UNAVAILABLE; C. A. Baker; NHTSA TO: Toyota Motor Company, Ltd. TITLE: FMVSS INTERPRETATION TEXT: Thank you for your letter of December 29, 1969, to Mr. J. E. Leysath of this Office, concerning an interpretation of paragraph S3.3 of Federal Motor Vehicle Safety Standard No. 108. The requirements and provisions of paragraph S3.3 are applicable to combinations of the required lamps, reflective devices and associated equipment as specified elsewhere in the standard. These requirements and provisions do not preclude the use of a non-required (ornamental) Class B reflex reflector in a combination rear lamp. I should also point out that effective January 1, 1970, the standard requires Class A rear reflex reflectors on all vehicles, including passenger cars. As you have proposed, such required Class A reflectors may be mounted separately from the combination rear lamp. |
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ID: nht70-1.41OpenDATE: 02/05/70 FROM: AUTHOR UNAVAILABLE; Clue D. Ferguson; NHTSA TO: G. F. Pierce Company TITLE: FMVSS INTERPRETATION TEXT: This is in reply to your letter of January 13, 1970, to Mr. W. S. Scott, and to your recent inquiry to Mr. James Gilkey, concerning your safety belt system. Federal Motor Vehicle Safety Standard No. 210 specifies the number of belt enchorages that must be provided and the performance and location requirements of these anchorages in passenger cars. This standard does not apply to seat belt assemblies. Seat belt assembly performance requirements are specified in Federal Motor Vehicle Safety Standard No. 209. I am enclosing copies of Standards Nos. 209 and 210 for your reference. Thank you for your interest in motor vehicle safety. |
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ID: nht68-1.7OpenDATE: 11/18/68 FROM: AUTHOR UNAVAILABLE; Charles A. Baker; NHTSA TO: Arcoa TITLE: FMVSS INTERPRETATION TEXT: Thank you for your letter of October 2, 1968, to Mr. David A. Fay, Office of Standards on Accident Avoidance, requesting an interpretation on the visibility of backup lamps on truck bodies. The optical center of the lens surface must be visible from any eye point in the area you have indicated on your drawing. This Bureau does not issue approval on items of lighting equipment or on vehicle designs incorporating this equipment; therefore, the above comment is for your information only, and in no way relieves the vehicle manufacturer from his responsibility for certifying that the assembled vehicle meets the requirements of Federal Motor Vehicle Safety Standard No. 108. Sincerely, |
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ID: nht68-2.12OpenDATE: 06/03/68 FROM: AUTHOR UNAVAILABLE; David A. Fay; NHTSA TO: Gruppe Autoelektrik TITLE: FMVSS INTERPRETATION TEXT: Thank you for your letters of March 7 and May 15, 1968, to Mr. George C. Nield, concerning the requirements for motorcycle headlamps as specified in Motor Vehicle Safety Standard No. 108. On motorcycles, Standard No. 108 permits the use of unscaled headlamps conforming to SAE Standard J584. You will note that this SAE standard does not reference bulb sockets conforming to SAE Standard J567, which is intended to insure functional compatibility between bulb sockets and the bulbs listed in SAE Standard J573. Therefore, the bulbs used in motorcycle headlamps conforming to SAE Standard J584 need not conform to SAE Standard J573. Thank you for writing. |
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ID: nht68-3.18OpenDATE: 03/12/68 FROM: AUTHOR UNAVAILABLE; Joseph R. O'Gorman; NHTSA TO: The Reuben H. Donnelley Corporation TITLE: FMVSS INTERPRETATION TEXT: Thank you for your letter of February 27, 1968, to the Federal Righway Safety Bureau, in regard to obtaining information about Safety Standard No. 209, seat belt assemblies. Regarding your question on seat belt usage as pertaining to a fire apparatus vehicle, seat belts are not required to be installed, however, if seat belts are installed on a truck by a manufacturer, the seat belt assemblies, as equipment, must meet the requirements of Standard 209, specifically, requirements of the Department of Commerce, National Bureau of Standards for seat belts for use in motor vehicles (15 CFR 9)(30 FR 8432). Thank you again for your interest in the safety program. |
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ID: nht70-2.32OpenDATE: 10/29/70 FROM: AUTHOR UNAVAILABLE; R. H. Compton; NHTSA TO: Leaseway Transportation Corporation TITLE: FMVSS INTERPRETATION TEXT: This is in reply to your letter of October 14, 1970, to Mr. Douglas W. Toms, Director, National Highway Safety Bureau requesting an interpretation on the "marker blink switch" relative to Federal Motor Vehicle Safety Standard No. 108. The use of this switch does not violate the requirements of paragraph S3.5 of Standard No. 108, and is permitted by paragraph S3.1.2. Flashing lights for signaling purposes in a highly controversial subject with many proponents for, and many against, their use. This aspect is being clarified in a soon-to-be-published amendment to Standard No. 108, and will be addressed further in a forthcoming notice of proposed rule making on the same standard. |
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ID: nht70-2.49OpenDATE: 01/02/70 FROM: AUTHOR UNAVAILABLE; C. A. Baker; NHTSA TO: Alba Tire Company TITLE: FMVSS INTERPRETATION TEXT: Thank you for your letter of November 24, 1969 to the National Highway Safety Bureau, concerning our proposed retreated tire standard. I appreciate your sending your thoughts on tire safety to our attention since we make a point of being as familiar as possible with the present state-of-the-art of all aspects to tire safety. The Federal Motor Vehicle Safety Standard do not apply to tires manufactured exclusively for off-road competitive use or to tires retreaded exclusively for off-road competitive use. You are cautioned, however, that if the tires are sold for "street use", then these racing tires wil be covered by the proposed standards and would be subject to the requirements. |
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ID: nht71-2.20OpenDATE: 03/24/71 FROM: AUTHOR UNAVAILABLE; Francis Armstrong; NHTSA TO: AGIP USA Inc. TITLE: FMVSS INTERPRETATION TEXT: This office is in receipt of your letter of February 25, 1971, requesting concurrence with your proposed letter to an automobile manufacturer who wishes to import vehicles into the United States using your brake fluid. Your proposed letter appears to adequately state the responsibility of the vehicle manufacturer, and as your letter indicates, the National Highway Traffic Safety Administration doesn't require that certification tests be conducted at Government approved laboratories. However, if your company plans to import brake fluid into the United States as an item of motor vehicle equipment rather than a part of a vehicle, proof of certification must be supplied by AGIP upon our request. We trust this will answer your questions. |
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ID: nht72-1.20OpenDATE: 05/31/72 FROM: AUTHOR UNAVAILABLE; Francis Armstrong; NHTSA TO: Armstrong Rubber Company TITLE: FMVSS INTERPRETATION TEXT: We are in receipt of your response of October 7, 1971, to CIR 368.1.1, concerning Admiral Belted 78 tires that were branded on one side only. The Administration considers the act of branding on only one sidewall at a time when the standard required both sidewalls be labeled, to be inexcusable. If similar incidents of overlooking requirements come to our attention we will pursue civil penalties. However, based on the information before us we are closing our files in this case with regard to both civil penalties and defect notification. The Administration reserves the right to reopen this file in the event that further violations of this nature come to its attention. |
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.