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: aiam0517OpenMr. John C. Latzer, Plant Manager, Mobilefreeze Co., Inc., P. O. Box 691, Parsons, KS, 67357; Mr. John C. Latzer Plant Manager Mobilefreeze Co. Inc. P. O. Box 691 Parsons KS 67357; Dear Mr. Latzer: This is in reply to your letter of September 7, 1971, to Mr. Sta Haransky, Truck Body and Equipment Association, Inc., concerning the mounting height of lamps and reflectors on your motorcycle trailers.; A copy of Federal Motor Vehicle Safety Standard No. 108, 'Lamps Reflective Devices and Associated Equipment' is enclosed for your information. The minimum mounting height for lamps and reflectors listed in Table IV of this Standard is 15 inches. We do not have the authority to exempt any motor vehicles from meeting these requirements.; Sincerely, E. T. Driver, Director, Office of Operating Systems, Moto Vehicle Programs; |
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ID: aiam0950OpenMr. R. H. Dobson, Industrial Fibers Division, Marketing--Technical, E. I. Du Pont De Nemours & Company, Wilmington, DE, 19898; Mr. R. H. Dobson Industrial Fibers Division Marketing--Technical E. I. Du Pont De Nemours & Company Wilmington DE 19898; Dear Mr. Dobson: This is in reply to your letter of December 7, 1972, to Mr. James S Gilky concerning Motor Vehicle Safety Standard No. 302, 'Flammability of Interior Materials,' and its possible application to infant restraint harnesses.; Standard No. 302 does not apply to aftermarket materials or components it applies only to those original components or materials of new vehicles specified in Paragraph S4.1 of the standard. Since an infant restraint harness is an aftermarket item of motor vehicle equipment, it is not subject to the requirements of the standard.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam3095OpenMr. David H. Lewis, Tiger Trading Corporation International, 1706 Broadway, Suite 401, Oakland, California 94612; Mr. David H. Lewis Tiger Trading Corporation International 1706 Broadway Suite 401 Oakland California 94612; Dear Mr. Lewis: This responds to your letter of July 26, 1979, concerning an 'afte market' motor vehicle accessory you plan to distribute. You describe the accessory as an item of clear plastic that affixes to the inside of the rear window 'to greatly improve the rear vision of the driver of a passenger vehicle.'; Standard No. 111, *Rearview Mirrors*, established performanc requirements for rearview mirror systems. The standard only applies to mirror installed as original equipment in motor vehicles and does not apply to replacement equipment such as the aftermarket accessory you intend to distribute. However, since the device you plan to distribute is an item of motor vehicle equipment, the recall and remedy provisions of the National Traffic and Motor Vehicle SAfety Act (the Act), as amended, (15 U.S.C. 1411-1420) would apply to any safety-related defect in your mirror accessory. A copy of the Act is enclosed.; If you have any further questions, please let me know. Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam1921OpenMr. Phil Martinez, Trailmaster Tanks, Inc., P.O. Box 13137, Fort Worth, TX 76118; Mr. Phil Martinez Trailmaster Tanks Inc. P.O. Box 13137 Fort Worth TX 76118; Dear Mr. Martinez: This responds to Trailmaster Tank's May 14, 1975, request for discussion of what constitutes the manufacture of a trailer in cases where used components from an existing vehicle are involved.; In response to a similar request from the Truck Trailer Manufacturer Association, the National Highway Traffic Safety Administration recently prepared a comprehensive discussion of this subject, a copy of which is enclosed for your information.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam0074OpenMr. Donald E. Clauson, President, Clauson Manufacturing Company, Inc., U.S. Highway 31-W, Bonnieville, KY 42713; Mr. Donald E. Clauson President Clauson Manufacturing Company Inc. U.S. Highway 31-W Bonnieville KY 42713; Dear Mr. Clauson: Your letter of May 20, 1968, to Mr. Bridwell, concerning pickup covers has been referred to me for reply.; Pickup covers which you describe are considered to be in the sam category as slide-in campers and are items of motor vehicle equipment for use in motor vehicles. As such pickup covers must meet the requirements of Federal Motor Vehicle Safety Standard No. 205, *Glazing Materials* - *Passenger Cars, Multipurpose Passenger Vehicles, Trucks, Buses and Motorcycles*.; Sincerely, William H. Risteen, Office of Standards on Crash- Injur Reduction, Motor Vehicle Safety Performance Service; |
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ID: aiam3583OpenMr. William Croix, Technical Maintenance, Manager, Puerto Rico Marine Management, Inc., G.P.O. Box 71306, San Juan, Puerto Rico 00936; Mr. William Croix Technical Maintenance Manager Puerto Rico Marine Management Inc. G.P.O. Box 71306 San Juan Puerto Rico 00936; Dear Mr. Croix: This is in response to your letter of July 9, 1982, to Mr. Elliott o this agency.; You have asked about Federal requirements for lighting of portabl containers secured to flat bed trailers. As those containers are the cargo of the trailers and not an integral part of them, the Federal lighting requirements (Motor Vehicle Safety Standard No. 108) apply only to the trailer. However, the individual States in which the trailers are operated may impose their own lighting requirements.; Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam0234OpenMr. Donald F. Clausen, Route 4, Menomonie, WI 54751; Mr. Donald F. Clausen Route 4 Menomonie WI 54751; Dear Mr. Clausen: Your postcard of March 9, 1970, to the Chicago Regional Office of th Interstate Commerce Commission has been forwarded to this office by Mr. F. B. Farrell, Regional Administrator for Region 4, Federal Highway Administration. In your card, you request a copy of I.C.C. requirements for a camping trailer you intend to build.; The I.C.C. regulations concerning equipment for trailers are no administered by the Bureau of Motor Carrier Safety, Federal Highway Administration, Department of Transportation. These regulations apply only to vehicles used in interstate commerce for commercial purposes. If you intend to build a camping trailer for your personal use, these regulations would not be applicable to it. Should this not be the case, however, I am enclosing a copy of these requirements for your information.; Federal motor vehicle safety standards, which are issued by th National Highway Safety Bureau pursuant to National Traffic and Motor Vehicle Safety Act of 1966, do apply to manufacturers of camping trailers which will be towed on public highways. At present, the only Federal standard applicable to trailers is Standard No. 108, 'Lamps(sic) Reflective Devices and Associated Equipment', and your trailer must conform to its requirements. I enclose a copy of this standard as amended, and a copy of the above mentioned Act.; I suggest you also consult state and local authorities for possibl other requirements which they may impose on trailers. If I may be of further assistance, please contact me.; Sincerely, Rodolfo A. Diaz, Acting Associate Director, Motor Vehicl Programs; |
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ID: aiam1600OpenMr. Roger J. Harris, President, Eagle Coach Company of Dallas, Inc., 5424 Gregg Street, Suite 109, Dallas, TX 75235; Mr. Roger J. Harris President Eagle Coach Company of Dallas Inc. 5424 Gregg Street Suite 109 Dallas TX 75235; Dear Mr. Harris: This is in reply to your letter of August 15, 1974, asking about 'thos requirements which presently exist for limited volume manufacturers.'; I enclose a copy of an information sheet that tells where you ma obtain the Federal motor vehicle safety standards and other regulations. No exceptions are automatically provided for limited volume manufacturers. Those whose total annual production is 10,000 units or less may petition for a temporary exemption from one or more standards upon the grounds that compliance would cause substantial economic hardship.; As a converter of production sedans into extended wheelbase vehicles and as a customizer of automobiles, your principal obligation is to insure that any new and previously untitled vehicle you sell and deliver to the ultimate purchaser conforms to all Federal motor vehicle safety standards applicable to passenger cars. This means that you should review the standards to determine whether your manufacturing operations affect conformity of any new vehicle as delivered to you that is certified by its manufacture as meeting Federal requirements. In any event, since your alterations consist of more than minor finishing operations you are required to attach the label described by Title 49, Code of Federal Regulations, Section 567.7, a copy of which I also enclose.; Yours truly, Richard B. Dyson, Acting Chief Counsel |
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ID: aiam4611OpenMr. Bob Sandblom President Bookland 8980 E. Indian Bend Road, Suite Dl Scottsdale, AZ 85256; Mr. Bob Sandblom President Bookland 8980 E. Indian Bend Road Suite Dl Scottsdale AZ 85256; Dear Mr. Sandblom: Thank you for your letter of May l8, l989, addresse to the Department, calling our attention to a dealer practice of placing overlays on the center of highmounted stop lamps. We have received a number of inquiries about this subject, and I enclose a representative response. You are correct that it is not legal for a dealer to create a noncompliance, but you will see from the letter enclosed that the practice is not in and of itself illegal provided that the lamp continues to meet the rather technical requirements of the standard after the overlay is required. We appreciate your interest in motor vehicle safety, and for taking the time to write us. Sincerely, Stephen P. Wood Acting Chief Counsel Enclosure; |
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ID: aiam0028OpenMr. L.L. Willis, Vice President - Engineering, Thermo King Corporation, 314 West 90th Street, Minneapolis, Minnesota 55420; Mr. L.L. Willis Vice President - Engineering Thermo King Corporation 314 West 90th Street Minneapolis Minnesota 55420; Dear Mr. Willis: Thank you for your letter of July 11, 1967, regarding the applicabilit of the Federal Motor Vehicle Safety Standards to accessories which are purchased for installation after procurement of the car, and in particular, Safety Standard No. 201.; Standard No. 201, 'Occupant Protection in Interior Impact -- Passenge Cars,' applies only to vehicles as originally equipped and does not apply to accessories such as 'after market' auto air conditioners. However, the public would certainly benefit from the maximum degree of conformance that may be feasible on after market installations.; It is sincerely regretted that a written response to your first reques was not received by you and trust that you were not inconvenienced.; Sincerely yours, George C. Nield, Acting Director, Motor Vehicle Safet Performance Service; |
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.