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: nht73-1.5OpenDATE: 02/22/73 FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA TO: Toyo Kogyo Co., Ltd. USA Rep. Ofc. TITLE: FMVSS INTERPRETATION TEXT: This is in reply to your letter of February 8, 1973 concerning the operating point of a hand-operating parking system (Standard No. 105a). We intend to specify an operating point in the response to petitions for reconsideration of Standard No. 105a. This notice should be published not later than May 1, 1973. Yours truly, Richard B Dyson -- Assistant Chief Councel, National Highway Traffic Safety Administrator U.S. Government of Transportation Dear Mr. Dyson Re; Operating Point of Hand Parking System Would you inform us your opinion regarded with 90 lb force applied to hand-operated parking system in MVSS 105A Docket No. 70-27 Notice 5 Section 5.2. In this regulation we cannot find the operating point. We would like to consider it on the middle finger in following figure. Your kind reply will be high appreciated, Sincerely yours, |
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ID: nht73-2.19OpenDATE: 08/20/73 FROM: AUTHOR UNAVAILABLE; Robert L. Carter; NHTSA TO: American Safety Equipment Corporation TITLE: FMVSS INTERPRETATION TEXT: In reference to your August 3, 1973, petition for rule making pertaining to Standard No. 213, we require additional information on your harness release mechanism prior to reaching any decision on this matter. Specifically, we require data on the amount of force required to open your release mechanism under the following conditions: 1. When the harness system is preloaded with the child body block to 45 pounds (according to the existing procedure in Standard No. 213); 2. When the harness system is preloaded to 45 pounds with a three-year-old Sierra child dummy (by pulling on the arms and legs of the dummy); and 3. When the child seating system with an actual child occupant is suspended upside down and when the harness system is not unloaded (pulling only on the latch mechanism without releasing the load on the harness). Your cooperation in furnishing us this data will aid in resolving this matter. |
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ID: nht73-2.41OpenDATE: 02/22/73 FROM: E.T. DRIVER -- NHTSA; SIGNATURE BY CHARLES A. BAKER TO: N. H. Dachs TITLE: FMVSS INTERPRETATION TEXT: This is in response to your letter of January 30, 1973, relating to the safety standard for automobile accelerators. On April 8, 1972, the National Highway Traffic Safety Administration (NHTSA) issued Federal Motor Vehicle Safety Standard No. 124, Accelerator Control Systems. This standard established requirements for accelerator control systems, effective September 1, 1973. In addition to the standard, two amendments were issued; one in September 1972 and the other in January 1973. Copies of the standard, plus the amendments, are enclosed for your review and further information. The NHTSA has not prepared or issued any reports relating to the safety standard; however, many comments were received in response to the proposed rule making action. These responses may be reviewed in the Docket Section, NHTSA, Room 5241, 400 Seventh Street, S.W., Washington, D.C. 20590. We trust that the above information will be useful to you. If we can be of any further service, please let us know. |
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ID: nht73-3.22OpenDATE: 02/08/73 FROM: AUTHOR UNAVAILABLE; Robert L. Carter; NHTSA TO: United States Senate TITLE: FMVSS INTERPRETATION TEXT: This is in reply to your letter of January 26, 1973, which was forwarded to the National Highway Traffic Safety Administration (NHTSA) by National Transportation Safety Board Chairman John H. Reed, regarding the position of the shoulder harness on the Toyota Corona purchased by Mr. John McCauley of Mattapan, Massachusetts. A copy of the constituent's letter is enclosed. Federal Motor Vehicle Safety Standard No. 208, Occupant(Illegible Word) Protection, requires that all cars made after January 1, 1972, have lap and shoulder belts which fit specified occupant sizes. Our Office of Standards Enforcement has made telephone contact in order to obtain more detailed information on Mr. McCauley's vehicle and the exact nature of the safety belt problems which he experienced. I appreciate Mr. McCauley's interest in motor vehicle safety and his bringing this situation to our attention. As we had recently received a similar complaint on another model Toyota automobile, our Office of Standards Enforcement is conducting an investigation of the entire matter. |
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ID: 7892Open Mr. Chester I. Nielsen, III Dear Mr. Nielsen: This responds to your letter of October 21, 1992, to Walter B. McCormick, Jr. (the General Counsel of this Department). You have written for "further explanation of S5.3.1.1.1 in FMVSS 108." You have heard that there is an additional interpretation with respect to the location of clearance lamps on boat trailers whose overall width is 80 inches or more, which would allow mounting of these lamps in accordance with a sketch that you enclosed, and you ask for confirmation of this interpretation. We are unaware of any interpretation of this nature. The requirements for the provision and location of clearance lamps on wide boat trailers remain those set forth in Tables I and II of Standard No. 108, with the exceptions set forth in paragraphs S5.1.1.9, S5.3.1.1.1, and S5.3.1.4. Sincerely,
Paul Jackson Rice Chief Counsel ref:108 d:12/1/92 |
1992 |
ID: 7912Open Mr. Chester I. Nielsen, III Dear Mr. Nielsen: This responds to your letter of October 21, 1992, to Walter B. McCormick, Jr. (the General Counsel of this Department). You have written for "further explanation of S5.3.1.1.1 in FMVSS 108." You have heard that there is an additional interpretation with respect to the location of clearance lamps on boat trailers whose overall width is 80 inches or more, which would allow mounting of these lamps in accordance with a sketch that you enclosed, and you ask for confirmation of this interpretation. We are unaware of any interpretation of this nature. The requirements for the provision and location of clearance lamps on wide boat trailers remain those set forth in Tables I and II of Standard No. 108, with the exceptions set forth in paragraphs S5.1.1.9, S5.3.1.1.1, and S5.3.1.4. Sincerely,
Paul Jackson Rice Chief Counsel ref:108 d:12/1/92 |
1992 |
ID: nht75-1.37OpenDATE: 09/18/75 FROM: AUTHOR UNAVAILABLE; M. I. Schwimmer; NHTSA TO: File TITLE: FMVSS INTERPRETATION TEXT: SUBJECT: Meeting concerning labeling requirements of Standard No. 106-74, Brake Hoses On September 16, 1975, a meeting was held with representatives of Volkswagen of America to discuss the labeling of short lengths of brake hose pursuant to Standard No. 106-74. The following persons were present: Cerherd Riechel VW Karl-Heinz Ziwica VW Welfred Redler NHTSA Mark Schwimmer NHTSA The Volkswagen representatives discussed difficulties they have experienced with the requirement that a full legend of the information specified in the standard appear on each brake hose, regardless of its length. They submitted samples of the hose in question and a photograph and drawing indicating its installation. They suggested that a sequence of hose segments, interrupted only by check valves or T-connectors, be considered a single brake hose for the purposes of the standard's labeling requirements. I explained that a Federal Register notice addressing the short hose issue is expected to be published in the near future. |
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ID: nht75-2.38OpenDATE: 08/11/75 FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA TO: The Budd Company TITLE: FMVSS INTERPRETATION TEXT: This is in response to your letter of July 8, 1975, asking which standards might be affected by the mounting of a tail lamp in the elastic skin of a bumper. Motor Vehicle Safety Standard No. 215, Exterior Protection, prescribes barrier and pendulum impact tests to which vehicles must be subjected without incurring certain types of damage. Included in the list of safety systems that must remain undamaged are lamps and reflective devices. S5.3.1 of Standard 215 states that each lamp or reflective device, except license plate lamps, must remain free of cracks and comply with the applicable visibility requirements of S4.3.1.1 of Standard No. 108, Lamps, Reflective Devices, and Associated Equipment. The manufacturer should be aware that placement of a tail lamp in the elastic skin of a bumper might expose it to damage during Standard 215 compliance testing. For your information, I have enclosed copies of the current Standard No. 215, the proposed Part 580 bumper damageability standard, and Standard No. 108. |
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ID: nht75-4.37OpenDATE: 06/26/75 FROM: AUTHOR UNAVAILABLE; R. L. Carter; NHTSA TO: Department of Public Instruction - Delaware TITLE: FMVSS INTERPRETATION TEXT: This letter is in further response to your phone call to Mr. David Soule, concerning the proper wording of captions above emergency doors and/or exits in school buses. While we do not consider the phrase "Emergency Door" to be synonymous with "Emergency Exit" (we do not believe push-out windows or other nondoor emergency exits are appropriately marked "Emergency Door"), we would not consider a bus failing to conform to Standard No. 217, Bus Window Retention and Release, if its emergency doors were marked "Emergency Door." Emergency exits other than doors, however, must be marked "Emergency exit." National Highway Traffic Safety Administration standards apply only to vehicles manufactured after a standard's effective date. Standard No. 217 does not apply to buses in use that were manufactured before its effective date of September 1, 1973. I might point out that a Federal Register notice published February 26, 1975, proposing requirements for emergency doors in school buses would require that such exits be designated "Emergency Door." |
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ID: nht68-1.21OpenDATE: 04/26/68 FROM: AUTHOR UNAVAILABLE; David A. Fay; NHTSA TO: Blue Bird Body Company TITLE: FMVSS INTERPRETATION TEXT: Thank you for your letter of March 19, 1968, to Mr. George C. Nield, requesting a clarification of paragraphs S3.4.4 and S3.4.4.1 of Motor Vehicle Safety Standard No. 108. In your letter you listed possible brake combinations as follows: 1. A vacuum over dual hydraulic brake system and a hand operated mechanical brake are provided. 2. A full air brake system and a hand operated mechanical brake are provided. 3. A full air brake system with a spring loaded emergency stopping system which is actuated at a pre-determined low air pressure level and a hand operated mechanical brake are provided. In accordance with the interpretation issued February 27, 1967 (32 F.R. 3390, copy enclosed), on "emergency brakes," the supplementary brake systems included in the above brake combinations are not emergency brakes. Therefore, paragraph S3.4.4 of Standard No. 108 does not require that the stop lamp be actuated upon application of these supplementary brakes. Thank you for writing. |
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.