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: nht95-1.75OpenTYPE: INTERPRETATION-NHTSA DATE: February 24, 1995 FROM: David T. Holland -- President, Europa International, Inc. TO: Mary Versailles -- Office of Chief Counsel, NHTSA TITLE: Via fax # 202-366-3820 RE: Request for clarification of passive restraint phase-in requirements of FMVSS 208. ATTACHMT: ATTACHED TO 4/3/95 LETTER FROM PHILIP R. RECHT TO DAVID T. HOLLAND (A43; STD. 208) TEXT: Dear Ms. Versailles, This letter is to follow up our recent phone conversation where-in you acknowledged that if Europa International, Inc. (R91-002) imports Canadian specification MPV's, such as the Chrysler Minivan, that meets the MPV passive restraint phase-in requirement s of FMVSS 208, Europa will be in compliance as it can count these vehicles toward the required percentage. Please acknowledge this letter by signing below and faxing back or by a letter from your office. Thank you for your assistance. Acknowledged by: Mary Versailles Office of Chief Counsel, NHTSA |
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ID: 11414WKMOpen Mr. Alex Tartakovsky Dear Mr. Tartakovsky: This responds to your letter of December 6, 1995, requesting information on any laws, standards, and/or regulations "covering snow chain use for roads and/or for motor vehicles." The short answer to your inquiry is that there are no Federal motor vehicle safety standards (FMVSS) or regulations regarding the use of snow chains. By way of background information, the National Highway Traffic Safety Administration (NHTSA) has the authority to issue FMVSSs applicable to new motor vehicles and new items of motor vehicle equipment. In this case, snow chains for use on motor vehicles would be considered motor vehicle equipment, defined at 49 U.S. Code '30102(7)(B) as any "part or component manufactured or sold for replacement or improvement of a system, part, or component." Thus, although NHTSA has the authority to regulate the manufacture and sale of snow chains, the agency has not done so. Some states regulate the use of snow chains, but this agency does not maintain such data. You may, however, be able to obtain some relevant information from: Automotive Manufacturers Equipment Compliance Agency, Inc. 1090 Vermont Avenue, NW, Suite 1200 Washington, DC 20005 Tel.: (202) 898-0145; FAX (202) 898-0745 I hope this information is helpful to you. Should you have any further questions or need additional information, please feel free to contact Walter Myers of my staff at this address or at (202) 366-2992. Sincerely,
Samuel J. Dubbin Chief Counsel Ref:VSA d:1/25/96 |
1996 |
ID: nht72-4.39OpenDATE: 12/07/72 FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA TO: Bluefield Mack Trucks Inc. TITLE: FMVSR INTERPRETATION TEXT: This is in reply to your letter of November 17, 1972, requesting information on alteration, and installation of fifth wheels, on new trucks. Persons who install fifth wheels on new trucks are generally considered to be "final-stage manufacturers" under NHTSA Certification regulations, and are required to certify that vehicles on which they install the fifth wheel conform to applicable Federal standards. The NHTSA has recently proposed requirements regarding persons who alter completed vehicles, and a copy of this proposal is enclosed. Copies of NHTSA requirements may be obtained as indicated on the enclosure, "Where to Obtain Motor Vehicle Safety Standards and Regulations." The regulations regarding the certification of motor vehicles are found at Parts 567 and 568 of Title 49 of the Code of Federal Regulations, (Item 1) and of the volume, "Federal Motor Vehicle Safety Standards and Regulations" (Item 3). |
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ID: nht90-1.85OpenTYPE: Interpretation-NHTSA DATE: March 26, 1990 FROM: Malcolm B. Mathieson -- Vice President-Engineering, Thomas Built Buses, Inc. TO: Erika Z. Jones -- Chief Counsel, NHTSA TITLE: Re Application of FMVSS 217 non-school bus emergency exit requirements to School Buses. ATTACHMT: Attached to letter dated 3-30-90 from M.B. Mathieson to M.F. Trentacoste; Also attached to letter dated 8-8-89 from M.F. Trentacoste to K. Finkel; Also attached to letter dated 9-29-77 from J.J. Levin, Jr. to M.B. Mathieson; Also attached to le tter dated 7-5-84 from F. Berndt to R. Marion; Also attached to letter dated 3-23-90 from A.H. Brett to M.B. Mathieson; Also attached to letter dated 12-3-90 from P.J. Rice to M. B. Mathieson (A36; Std. 217) TEXT: This letter transmits a copy of correspondence from Thomas Built Buses, Inc. to the Federal Highway Administration, Office of Motor Carrier Standards regarding the application of FMVSS 217 non-school bus emergency exit requirements to school buses. Thomas believes that we have correctly interpreted the application of FMVSS 217 in this instance. We would appreciate your office having the appropriate personnel review this matter and comment on the interpretations involved. Thank you for your consideration of this matter. |
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ID: nht75-2.30OpenDATE: 11/25/75 FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA TO: Dayton Wheel Prod., Inc. TITLE: FMVSS INTERPRETATION TEXT: This is in response to your letter of August 27, 1975 (117-1), requesting an interpretation of paragraph S3 of Federal Motor Vehicle Safety Standard No. 211, Wheel Discs, Wheel Nuts, and Hub Caps. Our interpretation of Standard No. 211 is that S3 prohibits winged projections that do not extend beyond the outer edge of the tire or rim, as well as those that do. We hope that this information will be of assistance. If you have any further questions, please contact us. Sincerely, ATTACH. DAYTON WHEEL PRODUCTS, INC. August 27, 1975 U.S. Department of Transportation -- National Highway Traffic Safety Administration Dear Sirs: This letter is to request an interpretation of Motor Vehicle Safety Standard No 211, section S3. We need to know what determines a "projection". We maintain that a "projection" must extend outside the plane drawn through the outermost side of the tire or rim. Any portion of the wheel that does not project beyond that plane would not constitute a hazard to pedestrians. Please send your comments on the above and a clarification on how the projection should be determined. Thank you for your assistance. Sincerely, James J. Schardt -- President c.c. Robt. E. Weltzer -- Highway Safety Management Specialist, DOT-NHTSA; Reference 117-1 |
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ID: nht72-2.48OpenDATE: 02/15/72 FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA TO: Pyroil Company, Inc. TITLE: FMVSS INTERPRETATION TEXT: This is in reply to your letter of February 7 to Lawrence R. Schneider requesting an interpretation of Motor Vehicle Safety Standard No. 116. No standard code numbering system has been established, and composition of the code is at the discretion of the manufacturers and packagers of brake fluid. Note that the use of a code is optional and not a requirement of paragraph S5.2.2.2(b). No standard format has been adopted for the serial number identifying the package lot and date of packaging, and this information may be incorporated into one code, explainable to this agency upon our request. |
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ID: nht94-9.3OpenTYPE: Interpretation-NHTSA DATE: January 11, 1994 FROM: Don Vierimaa -- Truck Trailer Manufacturers Association TO: Pat Boyd -- NHTSA TITLE: None ATTACHMT: Attached to letter dated 2/7/94 from John Womack to Don Vierimaa (A42; Std. 108) TEXT: A customer has requested that a 4 inch (100 mm) wide retroreflective sheeting be placed along the side of a trailer he is ordering. The manufacturer is reluctant to provide this width of sheeting since the rule states in S5.7.1.3(d) that Grade DOT-C2 sheeting shall have a width of 50 mm. This provides no tolerance nor does it provide a minimum. May a manufacturer install 4 inch (100 mm) wide retroreflective sheeting instead of 2 inch (50 mm) sheeting on the side of new trailers? |
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ID: nht94-1.18OpenTYPE: Interpretation-NHTSA DATE: January 11, 1994 FROM: Don Vierimaa -- Truck Trailer Manufacturers Association TO: Pat Boyd -- NHTSA TITLE: None ATTACHMT: Attached to letter dated 2/7/94 from John Womack to Don Vierimaa (A42; Std. 108) TEXT: A customer has requested that a 4 inch (100 mm) wide retroreflective sheeting be placed along the side of a trailer he is ordering. The manufacturer is reluctant to provide this width of sheeting since the rule states in S5.7.1.3(d) that Grade DOT-C2 sh eeting shall have a width of 50 mm. This provides no tolerance nor does it provide a minimum. May a manufacturer install 4 inch (100 mm) wide retroreflective sheeting instead of 2 inch (50 mm) sheeting on the side of new trailers? |
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ID: nht72-4.30OpenDATE: 11/02/72 FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA TO: Fordyce; Mayne; Hartman; Renard; & Stribling TITLE: FMVSR INTERPRETATION TEXT: This is in reply to your letter of October 10, 1972, requesting information on requirements applicable to the trucking industry regarding the reporting of numbers of vehicles produced. You also ask whether a person who adds a fifth wheel to complete a truck is a manufacturer who is subject to the requirements. Section 573.5(b) of NHTSA "Defect Reports" regulation (49 CFR Part 573) requires manufacturers of motor vehicles to report, on a quarterly basis, the total number of the manufacturer's vehicles by make, model, and model year, if appropriate, produced or imported during that quarter. This requirement applies to all manufacturers of complete or incomplete motor vehicles, including manufacturers of trucks. A person who adds a fifth wheel to an incomplete vehicle and completes the vehicle is considered to be a manufacturer under section 573.3 of the regulation, and is required to report production figures as part of his quarterly reports. |
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ID: nht89-2.36OpenTYPE: INTERPRETATION-NHTSA DATE: 07/19/89 FROM: THEO BOSE -- WEBASTO HEATER INC TO: FEDERAL HIGHWAY ADMINISTRATION TITLE: NONE ATTACHMT: ATTACHED TO LETTER DATED 05/31/90 FROM STEPHEN P. WOOD -- NHTSA TO THEO BOSE -- WEBASTER HEATER INC, A35, STD 301 TEXT: We are a improter and distributor of diesel fuel burning coolant heaters and air heaters for automotive applications. These units are often installed in busses or trucks to preheat the engine and/or provide supplementary heat to busses and school busses etc. We are often asked by OEM's to certify the unit as required under the above mentioned paragraph or to FMVSS 301-75. Fuel intergrity and safety are of high importance to us and we would like your comments about this subject to be able to furnish the proper documentation to our customer clientele. I have enclosed one typical installation manual for your review. Your earliest response is appreciated. Contact me if you have any questions. encl: DBW 2020 manual |
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.