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: nht87-3.43OpenTYPE: INTERPRETATION-NHTSA DATE: 12/10/87 FROM: THOMAS H. JAHNKE -- OASIS INDUSTRIES, INC. TO: CHIEF COUNSEL -- NATIONAL TRAFFIC SAFETY ADM. TITLE: NONE ATTACHMT: ATTACHED TO LETTER DATED 08/19/88 TO THOMAS H. JAHNKE FROM ERIKA Z. JONES, REDBOOK A32C4, STANDARD 205 TEXT: Dear Sirs, Oasis Industries, Inc. is a Fiberglass manufacture, located in the Midwest. We are in the process of coming out with a new product line of hardtops for convertable cars. I would like to find out, through the Dept. of Transportation, if their are any spec. we need to comply with for safety and or standards. In a conversation I had today with a Mr. Hunter, of the Dept. of Transportation, he explained that their were not any regulations of specs. on this type of product. Even though Mr. Hunter has verbally made this statement, we feel that it is necessary to get this commitment in writing. I would like to thank you in advance for your cooperation on the above matter. Sincerely, |
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ID: nht94-3.41OpenTYPE: Interpretation-NHTSA DATE: June 20, 1994 FROM: Irene M. Thomas (Aurora, CO) TO: Dee Fujita, NHTSA TITLE: CarMobile ATTACHMT: Attached to letter dated 8/26/94 from John Womack to Irene M. Thomas (A42; Std. 213) TEXT: Thank you for your time and consideration during our phone call this morning about my "CarMobile". Enclosed please find a notarized sketch and description. I would greatly appreciate an analysis in writing. Thank you! The CarMobile is a device which is attached by velcro strips to the handrails located at the top of the interior rear car doors. It is made of grosgrain ribbon, with three round rings sewn on to it. Toys can be hung from the rings, so that babies and t oddlers can play with them as they dangle in front of their carseats. The children can reach the toys, but not the CarMobile itself. The toys are not included with the CarMobile. Inventor: Irene Thomas Dated: June 21, 1994Notarized |
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ID: nht93-6.37OpenDATE: September 17, 1993 FROM: Angela R. Caron TO: Office of Chief Counsel, NHTSA TITLE: None ATTACHMT: Attached to letter dated 3/16/94 from John Womack to Angela R. Caron (A42; Redbook (2); Std. 208; Std. 213) TEXT: My letter is pertaining to the height of seat belts in cars. As you are probably aware, seat belts are not made for smaller people. Since the seat belts are not adjustable in either of my vehicles, I have been looking for alternative solutions. Enclosed are two ideas, SafeFit and the Child safer. My question is, is either of these restraints safe for an adult? I am 5 feet and of average weight. I would appreciate your input. It just seems so unsafe to have the seat belt across my neck, besides being very uncomfortable. I was also curious about the travel vest for my 2 1/2 year old son. Can it really replace his child safety seat? I thank you for your help on an issue as important as this.
ATTACHMENT SafeFit and Child Safer brochures. (Text omitted) |
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ID: nht95-3.41OpenTYPE: INTERPRETATION-NHTSA DATE: July 13, 1995 FROM: George E. Walton -- International Manufacturer's Consultants Inc. TO: Mr. John Womack -- Acting Chief Counsel, NHTSA TITLE: Reference: Federal Motor Vehicle Safety Standards No. 205, Glazing Materials - Passenger Cars, Multipurpose Vehicles, Motorcycles, Trucks and Buses. ATTACHMT: ATTACHED TO 08/04/95 LETTER FROM JOHN WOMACK TO GEORGE W. WALTON (REDBOOK 2; STD. 205) TEXT: Dear Mr. Womack: We represent a client who wishes to obtain your written comment on the use of the following glazing material in a motor vehicle: Our client wishes to use laminated "AS-1" Glass for motorcycle windshields. A motorcycle is described as a "Motor Vehicle", and the FMVSS-205 standard indicates by reference in the ANSI Z26.1 standard that "AS-1" glazing for use "Anywhere in a Motor Vehicle". Our client would like to have your written comment prior to producing several thousand motorcycle windshields from AS-1 glazing. Would you kindly address your comment to the undersigned. |
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ID: nht95-5.20OpenTYPE: INTERPRETATION-NHTSA DATE: July 13, 1995 FROM: George E. Walton -- International Manufacturer's Consultants Inc. TO: Mr. John Womack -- Acting Chief Counsel, NHTSA TITLE: Reference: Federal Motor Vehicle Safety Standards No. 205, Glazing Materials - Passenger Cars, Multipurpose Vehicles, Motorcycles, Trucks and Buses. ATTACHMT: ATTACHED TO 08/04/95 LETTER FROM JOHN WOMACK TO GEORGE W. WALTON (REDBOOK 2; STD. 205) TEXT: Dear Mr. Womack: We represent a client who wishes to obtain your written comment on the use of the following glazing material in a motor vehicle: Our client wishes to use laminated "AS-1" Glass for motorcycle windshields. A motorcycle is described as a "Motor Vehicle", and the FMVSS-205 standard indicates by reference in the ANSI Z26.1 standard that "AS-1" glazing for use "Anywhere in a Motor Vehicle". Our client would like to have your written comment prior to producing several thousand motorcycle windshields from AS-1 glazing. Would you kindly address your comment to the undersigned. |
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ID: nht71-1.6OpenDATE: 08/09/71 FROM: AUTHOR UNAVAILABLE; Robert L. Carter; NHTSA TO: Holen Company TITLE: FMVSS INTERPRETATION TEXT: This is in reply to your letters of June 30 and August 2 on the subject of the applicability of Standard No. 210 to multipurpose passenger vehicles, trucks, and buses as amended by notice of March 4, 1971 (36 F.R. 4291). The standard applies to these vehicles effective July 1, 1971, even though the heading published in the Register refers only to passenger cars. The application of the standard is controlled by the application section, S2, and not by the heading of the standard. The heading only reflects the substance of the application section and should automatically change whenever the application is changed. Through oversight, the Federal Register was given no instructions as to handing changes, and therefore inserted the old heading into the March 4 notice. Since the heading has no substantive role, and since the amendment is only in effect until the revised Standard No. 210 becomes effective January 1, 1972, we have not requested the Federal Register to alter the heading. I hope this is responsive to your question. |
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ID: nht71-4.10OpenDATE: 09/13/71 FROM: AUTHOR UNAVAILABLE; L. R. Schneider; NHTSA TO: Ray. C. Ellsworth Ranches TITLE: FMVSS INTERPRETATION TEXT: Thank you for your letter of September 2 inquiring whether your braking system hydraulic valve "is in conformity with the Federal Dual Braking Regulations now in effect." Federal Motor Vehicle Safety Standard No. 105, Hydraulic Service Brake, Emergency Brake, and Parking Brake Systems, applies to passenger cars, and not to individual items of motor vehicle equipment incorporated in a hydraulic brake system. Thus, there is no Federal Standard to which your valve must conform. If the valve is installed as original equipment in a passenger car, it is the vehicle that would be required to conform to the performance requirements of Standard No. 105. I have noted your comment that the valve is to be tested on braking systems for military vehicles. You may be interested to know that Federal Motor Vehicle Safety Standards, including No. 105, do not apply to vehicles manufactured for and sold to the Armed Forces of the United States. |
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ID: nht71-5.2OpenDATE: 11/17/71 FROM: AUTHOR UNAVAILABLE; J. W. Carson for E. T. Driver; NHTSA TO: Chrysler Corporation TITLE: FMVSS INTERPRETATION TEXT: This is in reply to your letter of November 4, 1971, to Mr. J. E. Leysath of this Office, concerning the maximum candlepower for taillamps as specified in Federal Motor Vehicle Safety Standard No. 108. Paragraph S5.1 of Standard No. 108 (35 FR, 16840, October 31, 1970) is quoted as follows: "S5.1 SAE Standards and Recommended Practices subreferenced by the SAE Standards and Recommended Practices included in Tables I and III and paragraphs S4.1.4 and S4.5.1 are those published in the 1970 edition of the SAE Handbook." Subreferenced SAE Standard J575, as published in the 1970 edition of the SAE Handbook, is the "d" revision (SAE J575d, August 1967). SAE Standard J575d specifies a maximum of 15 candlepower for a single compartment taillamp, 20 candlepower for a 2-compartment taillamp, and 25 candlepower for a 3-compartment taillamp. These maximum candlepower values are, therefore, applicable requirements under Standard No. 108 (35 FR, 16840, October 31, 1970). |
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ID: 16537.drnOpenMr. Karl-Heinz Ziwica Ref: A:FW22197 Dear Mr. Ziwica: This responds to your request for an interpretation of Standard No. 102, Transmission shift lever sequence, starter interlock, and transmission braking effect as it applied to a proposed BMW transmission design with electronic shifting controls. We have reviewed the arguments presented in your request for an interpretation, and cannot agree with BMW that S3.1.1 Location of transmission shift lever positions on passenger cars, S3.1.3 Starter interlock and S3.1.4 Identification of shift lever positions "are not applicable to automatic transmissions without a shift lever." However, the agency is carefully reviewing BMW's related petition for rulemaking submitted on November 19, 1997, the same date as the request for interpretation. The agency will inform you of its decision on the petition for rulemaking after it has completed its review of your petition. I hope this information is helpful. If you have any questions, please contact Dorothy Nakama of my staff at (202) 366-2992. Sincerely, |
1998 |
ID: nht78-2.41OpenDATE: 03/22/78 FROM: AUTHOR UNAVAILABLE; J. J. Levin, Jr.; NHTSA TO: Industrial Airport TITLE: FMVSS INTERPRETATION TEXT: This responds to your February 16, 1978, request for confirmation that Standard No. 121, Air Brake Systems, does not apply to an air-braked trailer that carries no cargo and consists entirely of a mobile auto-crushing device. Section S3 of Standard No. 121 contains an exclusion for any trailer whose unloaded vehicle weight is not less than 95 percent of its gross vehicle weight rating (GVWR). "Unloaded vehicle weight" means the weight of a vehicle with maximum capacity of all fluids necessary for operation of the vehicle, but without cargo or occupants. Thus, if your mobile auto-crushing trailer carries no cargo or cargo that is less than 5 percent of the vehicles GVWR, it would be excluded from the requirements of Standard No. 121. I would note that Standard No. 108, Lamps, Relective Devices and Associated Equipment, and Standard No. 120, Tire Selection and Rims for Motor Vehicles other than Passenger Cars, may apply to the trailer you describe. I enclose an information sheet that describes where copies of these standards can be obtained. |
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.