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: aiam1858OpenMr. M. Delen, Technical External Relations, Van Doorne's Personenautofabriek DAF B.V., Postbus: 1015, Geldropseweg 303, HOLLAND; Mr. M. Delen Technical External Relations Van Doorne's Personenautofabriek DAF B.V. Postbus: 1015 Geldropseweg 303 HOLLAND; Dear Mr. Delen: This is in response to your letter of March 17, 1975, asking whethe the pendulum test device sensors described in section S5.3.7 of the March 12, 1975, notice proposing to amend the Federal bumper standard must be installed for compliance testing if you can prove that no part of the test device, other than the impact ridge, will contact the vehicle.; Under the assumption of your letter, the force and pressure measurin sensors would not need to be installed on planes A and B of the pendulum test device during your compliance testing. A manufacturer is only obligated to exercise due care in assuring himself that his product is capable of meeting the performance requirements of applicable standards when tested in the manner prescribed. If a vehicle is constructed so that it does not touch planes A and B, there is no need to measure the force and pressure on those surfaces.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam2158OpenMr. S. L. Smead, Motocross Engineers, Inc., P.O. Box 861, Wilbraham, MA 01095; Mr. S. L. Smead Motocross Engineers Inc. P.O. Box 861 Wilbraham MA 01095; Dear Mr. Smead: This is in response to your letter of February 6, 1976, concerning th application of 49 CFR Part 574, *Tire Identification and Recordkeeping*, to certain off-road motorcycle tires that you plan to import.; 'Motor vehicle' is defined in Section 102(3) of the National Traffi and Motor Vehicle Safety Act of 1966 as:; >>>any vehicle driven or drawn by mechanical power manufacture primarily for use on the public streets, roads, and highways, except any vehicle operated exclusively on a rail or rails.<<<; The Tire Identification and Recordkeeping regulation does not apply t tires that are not manufactured for use on motor vehicles. From the description in your letter, it appears that the vehicles for which the tires in question are designed are not motor vehicles. Therefore, unless these tires are also designed for use on other vehicles that do meet the statutory definition of 'motor vehicle', they are not subject to any labeling requirements of the Department of Transportation.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam0291OpenMr. Y. Nakajima, Manager, Engineering Department, Koito Manufacturing Co., Ltd., 4-8-3, Takanawa, Minato-Ku, Tokyo, 108 Japan,; Mr. Y. Nakajima Manager Engineering Department Koito Manufacturing Co. Ltd. 4-8-3 Takanawa Minato-Ku Tokyo 108 Japan ; Dear Mr. Nakajima: This is in reply to your letter of January 22, 1971, to Mr. Charles A Baker of this Office concerning questions on paragraph S4.1.1.7 of Federal Motor Vehicle Safety Standard No. 108.; 'Red' was inadvertently included in paragraph S4.1.1.7 of the amendmen to Standard No. 108 published on October 31, 1970. It is anticipated that this paragraph will be further amended in the near future by changing '...requirements for Class A red turn signal lamps...' to '...requirements for Class A turn signal lamps...'; The answers to your questions are therefore as follows: >>>1. Amber turn signal lamps shall conform to the minimum candlepowe requirements for Class A amber as specified in Table 2 of SAE J575d.; 2. There is no maximum candlepower requirement for amber front tur signal lamps.<<<; Sincerely, Roger H. Compton, Director, Office of Operating Systems Motor Vehicle Programs; |
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ID: aiam0458OpenMr. Orlando Rodriguez, Export Manager, Blue Bird Body Company, Fort Valley, GA 31030; Mr. Orlando Rodriguez Export Manager Blue Bird Body Company Fort Valley GA 31030; Dear Mr. Rodriguez: Secretary Volpe has asked me to reply to your letter of October 18 1971, concerning the applicability of the National Traffic and Motor Vehicle Safety Act of 1966 in the territories and possessions of the United States.; The Act and the Federal motor vehicle safety standards issue thereunder apply in Puerto Rico, the Virgin Islands, the Canal Zone, Guam, and American Samoa. Motor vehicles, including buses, manufactured for sale and imported into those areas must meet all applicable Federal motor vehicle safety standards. Only one standard applicable to buses, No. 103, *Windshield Defrosting and Defogging Systems*, specifically does not apply to buses manufactured for sale outside the Continental United States. There are no Federal standards applicable to school bus bodies, so that the wooden bodied buses in American Samoa, of which you spoke, are not prohibited by the Act. School buses manufactured for sale in Puerto Rico are required, however, to have a warning light system.; I hope this clarifies the matter for you. Sincerely, Douglas W. Toms, Administrator |
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ID: aiam3151OpenMr. W.G. Milby, Manager, Engineering Services, Blue Bird Body Company, P.O. Box 937, Fort Valley, Georgia 31030; Mr. W.G. Milby Manager Engineering Services Blue Bird Body Company P.O. Box 937 Fort Valley Georgia 31030; Dear Mr. Milby: This is in response to your letter of March 29, 1979, requesting a interpretation of Federal Motor Vehicle Safety Standard No. 115 (49 CFR 571.115). We are sorry for the delay in responding.; You wish to know whether the 'body number' that Blue Bird Body Compan assigns to its school buses will satisfy the requirement of S4.5.3.3 that the last six characters of the Vehicle Identification Number (VIN) represent the production sequence of the vehicle. Your concern arises from the fact that the 'body number' does not indicate the true numerical sequence of manufacture. As explained in Notice 5 (43 Fr 36448) and Notice 6 (43 FR 52246) the production sequence represents the 'number sequentially assigned by the manufacturer in the production process' (S4.5.3.3), rather than the numerical sequence of actual manufacture. Consequently, the Blue Bird body number may be used as the production sequence number since the 'body numbers' are sequentially assigned when purchase orders for the buses are received.; Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam0776OpenMr. Robert S. Jacobs, 5-J Manufacturing, 7000 S. Angora Road, El Paso, TX 79934; Mr. Robert S. Jacobs 5-J Manufacturing 7000 S. Angora Road El Paso TX 79934; Dear Mr. Jacobs: This is in response to your letter of June 20, 1972, requesting copie of Department of Transportation requirements regarding the manufacture of small boats, truck camper shells, camping trailers, and boat trailers. The NHTSA does have requirements regarding some of these components. All truck campers are required to conform to Motor Vehicle Safety Standard No. 205, 'Glazing Materials,' while those campers designed for mounting on incomplete vehicles (as distinguished from those mounted on pick-up trucks) that are manufactured after September 1, 1972, must conform to Motor Vehicle Safety Standard No. 206, 'Door Locks and Door Retention Components.' Camping and boat trailers must conform to Standard No. 108, 'Lamps, Reflective Devices, and Associated Equipment.' In addition, manufacturers of these products (campers, trailers, etc.) must certify that their products conform to the standards in the manner set forth in the Certification regulations (49 CFR Parts 567, 568). Information on how to obtain copies of NHTSA requirements is enclosed.; We have referred your request for rules and regulations regarding th manufacture of small boats to the United States Coast Guard, and have requested that they respond directly to you.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam0449OpenMr. Paul H. Lawrenz, American Motors Corporation, 14250 Plymouth Road, Detroit, MI, 48232; Mr. Paul H. Lawrenz American Motors Corporation 14250 Plymouth Road Detroit MI 48232; Dear Mr. Lawrenz: This is in reply to your letter of September 21, 1971, to Mr. Lewis C Owen of this Office concerning an interpretation on the visibility requirements in FMVSS No. 108 as referenced in FMVSS No. 215.; Paragraph S4.3.1.1 of FMVSS No. 108 requires that the lamps be visibl at the extreme photometric test angles or as otherwise specified in the applicable SAE Standards. This paragraph does not require photometric tests at these extreme angles.; Sincerely, E. T. Driver, Director, Office of Operating Systems, Moto Vehicle Programs; |
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ID: aiam0450OpenMr. Paul H. Lawrenz, American Motors Corporation, 14250 Plymouth Road, Detroit, MI 48232; Mr. Paul H. Lawrenz American Motors Corporation 14250 Plymouth Road Detroit MI 48232; Dear Mr. Lawrenz: This is in reply to your letter of September 21, 1971, to Mr. Lewis C Owen of this Office concerning an interpretation on the visibility requirements in FMVSS No. 108 as referenced in FMVSS No. 215.; Paragraph S4.3.1.1 of FMVSS No. 108 requires that the lamps be visibl at the extreme photometric test angles or as otherwise specified in the applicable SAE Standards. This paragraph does not require photometric tests at these extreme angles.; Sincerely, E. T. Driver, Director, Office of Operating Systems, Moto Vehicle Programs; |
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ID: aiam1349OpenMr. Gorou Utsunomiya, Branch Manager, Toyo Kogyo U.S.A., Suite 462, 23777 Greenfield Road, Southfield, MI 48075; Mr. Gorou Utsunomiya Branch Manager Toyo Kogyo U.S.A. Suite 462 23777 Greenfield Road Southfield MI 48075; Dear Mr. Utsunomiya: This is in reply to your letter of December 6 to Mr. Lewis Owen of thi Office concerning the use of a special parking lamp bulb in one of your tail lamp assemblies.; The location of the subject bulb in the lamp assembly, regardless o whether the switch is removed to make it inoperative, is permitted, providing that the other required lamps function as specified in Federal Motor Vehicle Safety Standard No. 108.; Sincerely, E. T. Driver, Director, Office of Operating Systems, Moto Vehicle Programs; |
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ID: aiam0779OpenMr. Satoshi Nishibori, Engineering Representative, Liaison Office in U.S.A., 560 Sylvan Avenue, Englewood Cliffs, NJ, 07632; Mr. Satoshi Nishibori Engineering Representative Liaison Office in U.S.A. 560 Sylvan Avenue Englewood Cliffs NJ 07632; Dear Mr. Nishibori: This is in reply to your letter of June 29, 1972, concerning th application of Motor Vehicle Safety Standard No. 302, 'Flammability of Interior Materials', to replacement parts for vehicles manufactured on or after September 1, 1972.; Standard No. 302 does not apply to replacement parts or aftermarke materials irrespective of the date of their manufacture. It applies only to new vehicles manufactured on or after September 1, 1972, and not to the replacement materials used in those vehicles.; Yours truly, Richard B. Dyson, Assistant 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.