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: aiam2895OpenMr. W. G. Milby, Manager, Engineering Service, Blue Bird Body Company, P.O. Box 937, Fort Valley, GA 31030; Mr. W. G. Milby Manager Engineering Service Blue Bird Body Company P.O. Box 937 Fort Valley GA 31030; Dear Mr. Milby: This responds to your August 3, 1978, letter asking how to compute th area of a sample of a body panel when testing for compliance with Standard No. 221, *School Bus Body Joint Strength*.; In your letter, you suggest that the net cross- sectional area of th sample is determined by multiplying the width of the sample by its thickness and then subtracting the area of each discreet fastener hole. The National Highway Traffic Safety Administration agrees that this procedure yields the correct area of the sample, and it is the method used by the agency in its compliance testing.; Sincerely, Joseph J. Levin, Jr., Chief Counsel |
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ID: aiam1017OpenMr. J. C. Eckhold, Director, Automotive Safety Office, Ford Motor Company, The American Road, Dearborn, MI 48121; Mr. J. C. Eckhold Director Automotive Safety Office Ford Motor Company The American Road Dearborn MI 48121; Dear Mr. Eckhold: This is in reply to your letter of February 16, 1973, concerning th safety standard applicable to the sling for the upper torso belt used in Ford's 1974 model restraint system.; The schematic drawing attached to your letter shows that the slin attaches to the roof rail and serves the function of an upper torso belt anchorage. We agree with you that the sling is subject to the requirements of Standard No. 210 and not to the requirements of Standard No. 209. Although the sling is made of fabric webbing, its function is that of an anchorage and it is therefore subject to the anchorage standard.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam1533OpenMr. Robert C. Gibson,Imperial-Eastman Corporation,6300 West Howard Street,Chicago, Illinois 60648; Mr. Robert C. Gibson Imperial-Eastman Corporation 6300 West Howard Street Chicago Illinois 60648; Dear Mr. Gibson:#This responds to your May 2, 1974, question concerning the labeling of multi-piece end fittings, the use of hose marked with the DOT symbol in non-brake applications, and the acceptability of an end fitting design under the requirements of Standard No. 106, *Brake hoses*.#The answers to your first two questions will appear in the upcoming notice responding to petitions for reconsideration of amendments to Standard No. 106. #As to the acceptability of a certain end fitting design , the standard specifies performance requirements for end fittings. Any design which meets the specifications of the standard may be manufactured after the effective date of the standard.#Yours truly,Richard B. Dyson,Assistant Chief Counsel; |
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ID: aiam0456OpenMr. Davis Piper, Vice President, Forse Cleanamation, 1500 West Second Street, Anderson, IN 46011; Mr. Davis Piper Vice President Forse Cleanamation 1500 West Second Street Anderson IN 46011; Dear Mr. Piper: This is in reply to your letter of September 29, 1971, to Mr. J.E Leysath of this Office requesting information relative to the lighting requirements applicable to your E-Z Tow towing unit.; The E-Z Tow unit is a 'motor vehicle' as defined by the Nationa Traffic and Motor Vehicle Safety Act of 1966 since it is a 'vehicle . . . drawn by mechanical power manufactured primarily for use on the public streets, roads, and highways.' However, since it is designed to 'tow' rather than to 'carry' property, the E-Z Tow unit is not a 'trailer' as defined for purposes of the Federal Motor Vehicle Safety Standards. Since it is an unclassified 'motor vehicle,' the lighting requirements of Federal Motor Vehicle Safety Standard No. 108 are not applicable, therefore, you need only to comply with the lighting requirements of the States in which you sell or use the unit.; Sincerely, E. T. Driver, Director, Office of Operating Systems, Moto Vehicle Programs; |
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ID: aiam3328OpenJames. R. Clifton, P.O. Box 237, Bessemer, AL 35021; James. R. Clifton P.O. Box 237 Bessemer AL 35021; Dear Mr. Clifton: This is in response to your telephone conversation with Kathy DeMete of my staff on Tuesday, September 2, 1980. You asked for the status of section 580.5(a)(1) of Title 49 of the Code of Federal Regulations. That section exempts from the odometer disclosure requirements anyone transferring a vehicle having a gross vehicle weight rating of more than 16,000 pounds. That exemption is part of the regulation, originally issued in January 1973, which prescribes rules requiring a transferor of a motor vehicle to make a written disclosure to the transferee concerning the odometer reading and its accuracy.; In January 1977, the exemption was declared void by the United State District Court for the District of Nebraska on the grounds that the National Highway Traffic Safety Administration (NHTSA) has exceeded its authority in fashioning the exemption. Notwithstanding the court's decision, the NHTSA believes that it has the authority to create exemptions for vehicles for which the odometer reading is not relevant. The exemption, consequently, remains a part of the odometer disclosure regulations.; Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam0221OpenJohn S. Cushman, Esq.,Special Assistant Attorney General, Consumer Division, 102 State Capitol, St. Paul, Minnesota 55101; John S. Cushman Esq. Special Assistant Attorney General Consumer Division 102 State Capitol St. Paul Minnesota 55101; Dear Mr. Cushman: Your letter of February 16, 1979, transmitting Mr. John M. Schneider' letter, concerning tire selection for his 25,500-lb. GVW Truck, to the Federal Trade Commission has been referred to the National Highway Safety Bureau for reply.; There are no Federal standards at the present time for Tire Selectio and Rims for trucks. We are currently in the rule making phase to establish such a standard, however, we anticipate the effective date of this standard to be more than a year in the future.; The lack of Federal Standards in no way relieves a vehicle manufacture from his responsibility to design vehicles with equipment that will perform safely. this was evidenced in recent negotiations between General Motors and the National Highway Safety Bureau on a problem concerning three piece Kelsey-Hayes wheels. As you may know, at present, there are no standard covering wheel performance.; Sincerely, Rodolfo A. Diaz, Acting Associate Director, Motor Vehicl Programs; |
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ID: aiam1944OpenMr. John S. Hickman, President, Hickman Hampel Corp., 4149 North Stowell Avenue, Milwaukee, WI 53211; Mr. John S. Hickman President Hickman Hampel Corp. 4149 North Stowell Avenue Milwaukee WI 53211; Dear Mr. Hickman: This is in response to your letter of March 10, 1975, petitioning th National Highway Traffic Safety Administration to authorize the use of tempered glass for motorcycle windscreens.; As you know, Standard No. 205 and USAS Z26.1 prohibits the use o tempered glass in motorcycle windscreens. The rationale for this requirement is that tempered glass when impacted either shatters, showering the operator with glass pellets, or crazes, thereby obscuring the operator's vision. Consequently, while there are definite safety advantages to the use of windshield wipers, it is our view that they do not offset the dangers cited above. Your petition, therefore, is denied.; We trust you will be able to find a laminated glass or acrylic whic meets both your requirements and our standard, and wish you success in this endeavor.; Sincerely, Robert L. Carter, Associate Administrator, Motor Vehicl Programs; |
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ID: aiam0999OpenMr. D. S. Mitchell, Glass Sales Manager, Canadian Pittsburgh Industries Ltd., 1060 Arlington Street, Winnipeg 3, Manitoba, Canada; Mr. D. S. Mitchell Glass Sales Manager Canadian Pittsburgh Industries Ltd. 1060 Arlington Street Winnipeg 3 Manitoba Canada; Dear Mr. Mitchell: This is in reply to your letter of December 22, 1972, which wa forwarded to us by the Department of Transport of Canada, requesting assignment of a manufacturer's code number for glazing materials you manufacture.; In your letter you indicate that the glazing in question is purchase in stock sheets, and then cut to the customer's requirements. The assignment of Code numbers is limited to what NHTSA has called 'prime glazing material manufacturers' and this group includes only those who 'fabricate, laminate, or temper the glazing material.' As your function appears to be only that of cutting the material to size, we would not consider you, at least with respect to this material, to be a prime glazing material manufacturer. Consequently, a code number assignment would be improper. The labeling requirements which you would be subject to, if this glazing as cut by you is to be imported into the United States, are those requirements specified in S6.4 and S6.5 of Motor Vehicle Safety Standard No. 205, copy enclosed.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam4118OpenMr. Jost Leite, Hanover Marketing & Trade Corporation, 1703 N.W. 38th Avenue, Lauderhill, FL 33311; Mr. Jost Leite Hanover Marketing & Trade Corporation 1703 N.W. 38th Avenue Lauderhill FL 33311; Dear Mr. Leite: This responds to your letters to this office which, in effect, aske about a manufacturer's certification responsibilities and who has the authority to determine a product does not comply with an applicable Federal motor vehicle safety standard. I regret the delay in our response. I hope the following discussion answers your questions.; The National Traffic and Motor Vehicle Safety Act establishes self-certification requirement for manufacturers. Thus, it is the responsibility of each manufacturer to certify that its products are in compliance. Under the Act, only the manufacturer of the product or the agency can formally determine that a product is not in compliance and commence a notification and remedy campaign.; The public is encouraged to notify this agency if they believe potential noncompliance exists in a particular product. The agency will, if appropriate, begin a compliance investigation. However, this agency could not and has not authorized any member of the private industry to conduct compliance investigations.; I hope this responds to your concerns. Please contact my office if yo have further questions.; Sincerely, Erika Z. Jones, Chief Counsel |
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ID: aiam2722OpenMr. Philip H. Taft, Director, Tire Retreading Institute, National Tire Dealers & Retreaders Association, Inc., 1343 L Street, N.W., Washington, D.C. 20005; Mr. Philip H. Taft Director Tire Retreading Institute National Tire Dealers & Retreaders Association Inc. 1343 L Street N.W. Washington D.C. 20005; Dear Mr. Taft: This responds to your October 27, 1977, letter asking whether a tir retreader is permitted to change the designation of a tire from 'tubeless' to 'tubetype'.; Standard No. 117, *Retreaded Pneumatic Tires*, requires that th information appearing on the tire sidewall be the same as that which appeared on the tire as originally manufactured. This is indicated by the language in paragraph S6.3. If a retreader changed the tire designation from 'tubeless' to 'tubetype', he would be altering the information that was associated with the original tire. Thus, a retreader is not permitted to change the tire designation in the manner you describe.; Sincerely, Joseph J. Levin Jr., 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.