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: nht78-3.42OpenDATE: 11/14/78 FROM: AUTHOR UNAVAILABLE; John Womack; NHTSA TO: McClintock Donovan Carson & Roach TITLE: FMVSR INTERPRETATION TEXT: This is in response to your letter of September 1, 1978, requesting information on the Federal odometer disclosure requirements. You specifically asked what a lessor's responsibility is with regard to the certifications on the disclosure statement. The lessor, as transferor of a vehicle, is required to certify, to the best of his knowledge, as to the accuracy of the vehicle's odometer. A lessor should assume that an odometer is accurate unless he has reason to believe otherwise. Any reasonable belief that the odometer is wrong should be reflected on the disclosure statement by checking, in the first set of certifications, either box 2 or 3, as appropriate. In situations where the lessor has no knowledge as to the accuracy of the odometer reading, he should not state that the mileage is in error because to the best of his knowledge it is correct. With regard to the second set of certifications, the lessor should check box 1 unless he altered or knows that the lessee or some other person altered the odometer. Since your client is concerned about the possibility that the lessee may alter the odometer, he may find it advisable to protect himself by requiring the lessee to indemnify him in the event of liability under the Motor Vehicle Information and Cost Savings Act. He may also add a statement on the disclosure form that the vehicle was subject to a lease or was otherwise outside of his control. |
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ID: nht74-4.43OpenDATE: 01/15/74 FROM: AUTHOR UNAVAILABLE; E. T. Driver; NHTSA TO: Farrar & Farrar TITLE: FMVSS INTERPRETATION TEXT: This is in reply to your letter of December 17, 1973, regarding rules and regulations pertaining to tire ply bonding and adhesion strength, and to tire ratings as related to number of plies. There are no Federal regulations that contain specific requirements for ply bending and adhesion strength, per se, in tires. However, a measure of tire structural strength is provided by the plunger energy test included in Federal Motor Vehicle Safety Standard No. 109, copy enclosed. The high speed and endurance tests also form a part of the tire evaluation process. Poor bonding and adhesion of plies could cause premature separation and failure in these tests. There is no categorization in the Federal standard that relates tire mating to number of plies, except that labeling of tire sidewalls is required to express values for load rating, maximum inflation, and number of plies. The enclosed booklet entitled "Consumer Tire Guide" shows in its tables of tire load limits how ply ratings have been related to load ratings in tire industry practice. Recent trend in the industry has been to phase out the ply rating system and to substitute in its place the "load range" system denoted by markings with letters. With regard to test methods and procedures used in tire analysis, we recommend your examination of the following standards of the American Society for Testing Materials (ASTM) and the American National Standards Institute (AMSI). ASTM 885-72 "Tire Cords, Tire Cord Fabrics and Industrial Filament Yarns made from Man-made Organic Base Fibers" 1973 Edition or ANSI-L 14.231-1973 (2nd Edition) approved August 10, 1973. ASTM D 2969-71T "Tire Cords, Tire Cord Fabrics, Filaments, and Strands made from Wire" ASTM D 2970-71T "Tire Cords, Tire Cord Fabrics, and Industrial Yarns made from Class" ENCLS. |
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ID: nht75-6.1OpenDATE: 08/19/75 FROM: AUTHOR UNAVAILABLE; Frank A. Berndt; NHTSA TO: International Development Service Inc. TITLE: FMVSR INTERPRETATION TEXT: This is in reply to your letter of July 8, 1975, asking our opinion on several matters. You first ask: "1. If our automobile is imported using a used chassis and where a used or rebuilt engine would be installed in the car in the United States, would you consider that this constitutes the vehicle being classified as used? We consider a vehicle with a used chassis to be a used automobile. 2. If a used chassis is defined as being used by its being previously titled, does it matter where the titling has occurred? As the previous answer indicates, it does not matter where titling has occurred. 3. If we import, complete, and sell the car under the conditions stated in number one and your opinion was that this constitutes a used vehicle, then, what would our requirements be in reference to the vehicles complying with the Motor Vehicle Safety Standards under the Act of 1966?" Federal motor vehicle safety standards apply to used vehicles, that are imported into the United States. The standards are those that were in effect on the date of manufacture of the chassis. Further, you would be a manufacturer of motor vehicles and subject to all regulations that apply to manufacturers, chief of which is to notify purchasers upon discovery of any safety-related defect in your product, and to remedy it. Your fourth question asks what your responsibilities are under four possible plans of shipping components into the United States. I will assume for purposes of this answer that the chassis are new. These four fact situations differ somewhat from the hypothetical presented in your letter of May 31, 1975, of a motor vehicle complete except for its engine. In these four situations, the vehicle is clearly motor vehicle equipment, an assembly that needs further manufacturing operations for completion, and the remarks of Mr. Schultz in his letter of May 5 on this matter set forth your obligations as a supplier of equipment. |
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ID: nht92-9.58OpenDATE: January 7, 1992 FROM: Stephen C. Bartch -- Applications Engineer, Quigley Motor Company, Inc. TO: Office of Chief Council, NHTSA TITLE: None ATTACHMT: Attached to letter dated 2/18/92 from Paul Jackson Rice to Stephen C. Bartch (A39; Part 567; Std. 301) TEXT: We propose to convert the Ford E-series vans to our 4X4 drive system; however, the tank in the 1992 vans interferes with our transfer case placement. After much consideration and examining other Ford tank arrangements on 4X4 vehicles, we came to the conclusion that to keep certification costs down and still show due-care in reference to FMVSS 301, we should either: A. find a tank manufacturer that can build a tank with identical attachments as the OEM tank, or B. modify the OEM tank to eliminate the interference. We found a tank supplier who can manufacture the tank to our specifications, so we can pursue both options. The question that some of our customers are asking is about the legality of our fuel tank retrofit in regards to FMVSS 301. Could you summarize in writing our responsibilities regarding FMVSS 301 and state that we are not required by law to do crash testing on our vehicles? Thank you for your cooperation and willingness to accommodate us. |
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ID: nht94-4.41OpenTYPE: INTERPRETATION-NHTSA DATE: October 01, 1994 EST FROM: Womack, John -- Acting Chief Counsel, NHTSA TO: March, Gary D. -- Director, Illinois Dept. of Transportation, Division of Traffic Safety TITLE: NONE ATTACHMT: Attached To 2/14/94 Letter From Gary D. March To John Womack (Occ 9667) TEXT: This responds to your letter of February 14, 1994, requesting an explanation of the compliance date for vehicles manufactured in two or more stages of a recent final rule amending Standard No. 217, Bus Emergency Exits and Window Retention and Release (57 FR 49413; November 2, 1992). The effective date for the November 2 final rule is May 2, 1994. Only vehicles manufactured on or after the effective date of an applicable requirement in a Federal motor vehicle safety standard must comply with that requirement. If a vehicle is manufa ctured in two or more stages, the final stage manufacturer is required to certify that the vehicle complies with "the standards in effect on the date of manufacture of the incomplete vehicle, the date of final completion, or a date between those two date s." (49 CFR Part @ 568.6). The choice of a date is the manufacturers. I hope you find this information helpful. If you have any other questions, please contact Walter Myers of my staff at this address or by phone at (202) 366-2992. |
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ID: nht94-1.94OpenTYPE: Interpretation-NHTSA DATE: March 24, 1994 FROM: John Womack -- Acting Chief Counsel, NHTSA TO: Gary D. March -- Director, Illinois Dept. of Transportation, Division of Traffic Safety (Springfield, IL) TITLE: None ATTACHMT: Attached to letter dated 2/14/94 from Gary D. March to John Womack (OCC 9667) TEXT: This responds to your letter of February 14, 1994, requesting an explanation of the compliance date for vehicles manufactured in two or more stages of a recent final rule amending Standard No. 217, Bus Emergency Exits and Window Retention and Release (57 FR 49413; November 2, 1992). The effective date for the November 2 final rule is May 2, 1994. Only vehicles manufactured on or after the effective date of an applicable requirement in a Federal motor vehicle safety standard must comply with that requirement. If a vehicle is manufa ctured in two or more stages, the final stage manufacturer is required to certify that the vehicle complies with "the standards in effect on the date of manufacture of the incomplete vehicle, the date of final completion, or a date between those two date s." (49 CFR Part S568.6). The choice of a date is the manufacturers. I hope you find this information helpful. If you have any other questions, please contact Walter Myers of my staff at this address or by phone at (202) 366-2992. |
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ID: 9667Open Gary D. March, Director Dear Mr. March: This responds to your letter of February 14, 1994, requesting an explanation of the compliance date for vehicles manufactured in two or more stages of a recent final rule amending Standard No. 217, Bus Emergency Exits and Window Retention and Release (57 FR 49413; November 2, 1992). The effective date for the November 2 final rule is May 2, 1994. Only vehicles manufactured on or after the effective date of an applicable requirement in a Federal motor vehicle safety standard must comply with that requirement. If a vehicle is manufactured in two or more stages, the final stage manufacturer is required to certify that the vehicle complies with "the standards in effect on the date of manufacture of the incomplete vehicle, the date of final completion, or a date between those two dates." (49 CFR Part 568.6). The choice of a date is the manufacturer's. I hope you find this information helpful. If you have any other questions, please contact Walter Myers of my staff at this address or by phone at (202) 366-2992. Sincerely,
John Womack Acting Chief Counsel ref:586#217 d:3/17/94 |
1994 |
ID: 3270yyOpen Mr. Tony Llama Dear Mr. Llama: This responds to your letter of December 13, l99l, with respect to the permissibility of temporarily importing a Fiat from Brazil that is not in conformance with the Federal motor vehicle safety standards. The purpose of the importation is to design and build an air conditioning system for the car. Upon completion of this work, the Fiat will be exported. You have enclosed a copy of my letter of August 2, 1990, granting permission for the importation of a van manufactured in the Soviet Union for which you had been asked to design an air conditioning system. In that letter, I informed you that it would be appropriate for you to enter the van pursuant to 49 CFR section 591.5(j), under the declaration that the vehicle is being imported solely for the purpose of research, investigations, and studies or demonstrations. Under the circumstances outlined in your letter, we believe that it would be appropriate for you to enter the Brazilian Fiat as well under section 591.5(j). If you have any further questions, we shall be happy to answer them. Sincerely,
Paul Jackson Rice Chief Counsel /ref:59l d:l/3/92 |
1970 |
ID: nht92-9.60OpenDATE: January 3, 1992 FROM: Paul Jackson Rice -- Chief Counsel, NHTSA TO: Tony Llama -- President, Davenport Enterprises TITLE: None ATTACHMT: Attached to letter dated 12/13/91 from Tony Llama to Paul Jackson Rice (OCC 6784) TEXT: This responds to your letter of December 13, 1991, with respect to the permissibility of temporarily importing a Fiat from Brazil that is not in conformance with the Federal motor vehicle safety standards. The purpose of the importation is to design and build an air conditioning system for the car. Upon completion of this work, the Fiat will be exported. You have enclosed a copy of my letter of August 2, 1990, granting permission for the importation of a van manufactured in the Soviet Union for which you had been asked to design an air conditioning system. In that letter, I informed you that it would be appropriate for you to enter the van pursuant to 49 CFR section 591.5(j), under the declaration that the vehicle is being imported solely for the purpose of research, investigations, and studies or demonstrations. Under the circumstances outlined in your letter, we believe that it would be appropriate for you to enter the Brazilian Fiat as well under section 591.5(j). If you have any further questions, we shall be happy to answer them. |
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ID: nht94-7.25OpenDATE: March 24, 1994 FROM: John Womack -- Acting Chief Counsel, NHTSA TO: Gary D. March -- Director, Illinois Dept. of Transportation, Division of Traffic Safety (Springfield, IL) TITLE: None ATTACHMT: Attached to letter dated 2/14/94 from Gary D. March to John Womack (OCC 9667) TEXT: This responds to your letter of February 14, 1994, requesting an explanation of the compliance date for vehicles manufactured in two or more stages of a recent final rule amending Standard No. 217, Bus Emergency Exits and Window Retention and Release (57 FR 49413; November 2, 1992). The effective date for the November 2 final rule is May 2, 1994. Only vehicles manufactured on or after the effective date of an applicable requirement in a Federal motor vehicle safety standard must comply with that requirement. If a vehicle is manufactured in two or more stages, the final stage manufacturer is required to certify that the vehicle complies with "the standards in effect on the date of manufacture of the incomplete vehicle, the date of final completion, or a date between those two dates." (49 CFR Part S568.6). The choice of a date is the manufacturers. I hope you find this information helpful. If you have any other questions, please contact Walter Myers of my staff at this address or by phone at (202) 366-2992. |
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.