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: aiam3605OpenMr. R. H. Zelinski, Vice President, Corporate Engineering, Zimmer Corporation, P.O. Box 2127, Pompano Beach, FL 33061; Mr. R. H. Zelinski Vice President Corporate Engineering Zimmer Corporation P.O. Box 2127 Pompano Beach FL 33061; Dear Mr. Zelinski: Thank you for your letter of August 6, 1982, to the Administrato asking whether there is 'any blanket waiver of standards solely based on a small production of vehicles.'; You are correct that no such waiver exists. Even a single automobil manufactured for use on the public roads must meet all applicable Federal motor vehicle safety standards unless exempted by the Administrator under the provisions of Part 555. A manufacturer whose total motor vehicle production in the year preceding filing of his petition does not exceed 10,000 units is eligible to apply for an exemption of up to three years on a hardship basis. Any manufacturer of motor vehicles may apply for an exemption of up to two years on the three remaining bases that you mention but the exemption extends only to a maximum of 2500 vehicles in any 12-month period that the exemption is in effect.; Under the original exemption authority, in effect from 1968 to 1971 exemptions were available on a hardship basis and the threshold of eligibility was 500 units.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam3285OpenMr. Hiroshi Abe, Assistant General Manager, Isuzu Motor America, Inc., 21415 Civil Center Drive, Southfield, Michigan 48076; Mr. Hiroshi Abe Assistant General Manager Isuzu Motor America Inc. 21415 Civil Center Drive Southfield Michigan 48076; Dear Mr. Abe: This is in response to your letter of April 3, 1980, concerning th application of Federal Motor Vehicle Safety Standard No. 115 to incomplete vehicles.; S4.1 of Standard No. 115 provides that '(e)ach vehicle manufactured i more than one stage shall have a VIN and check digit assigned by the incomplete vehicle manufacturer.' Consequently, Isuzu Motors, Inc. would be the entity responsible for assigning the vehicle identification number (VIN) to incomplete vehicles which it ships to the United States.; You wish to know whether the manufacturer identifier in the VIN of eac of these vehicles may designate the vehicle as a 'truck' instead of as an 'incomplete vehicle' if Isuzu knows that the complete vehicle will be a truck.; S4.5.1 of the standard provides that the first three characters of th VIN shall identify the manufacturer, make and type of vehicle. Table I of S4.5.2 delineates the different types of vehicles and includes a separate type designation for 'incomplete vehicles'. as explained in the preamble to Notice 8 (March 22, 1979, 44 FR 17489, at 17490), the 'incomplete vehicle' category was added because 'incomplete vehicle manufacturers would have little way of knowing the final configuration of the vehicle they produce.' It was never the intent of the agency, however, to preclude a manufacturer from indicating the precise types of completed vehicles if this is known.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam2945OpenMr. T. Szkolnicki, Mechanical Engineering, Motor Coach Industries, Inc., Pembina, ND 58271; Mr. T. Szkolnicki Mechanical Engineering Motor Coach Industries Inc. Pembina ND 58271; Dear Mr. Szkolnicki: This responds to your January 2, 1979, request for confirmation that July 23, 1976, interpretation of S5.3.3 and S5.3.4 of Standard No. 121, *Air Brake Systems*, has been incorporated into the body of the regulation. I regret that you did not receive a reply to your letter of November 27, 1978, which was addressed to someone who is no longer in this office.; The interpretation in question has not been incorporated into the bod of the regulation. During a court review of the standard which only recently concluded, the agency was making as few changes to the standard as possible. Consideration is now being given to revision of the standard in minor respects, but no date has been established for action. Until any such action is taken, you may continue to rely on the July 23, 1976, interpretation as the agency's official view of the meaning of S5.3.3 and S5.3.4.; Sincerely, Joseph J. Levin, Jr., Chief Counsel |
|
ID: aiam3918OpenMr. Robert M. Levy, Manager, Design Engineering, Abex Corporation, Signal-Stat Division, P.O. Box 438, Somerset, NJ 08873-3492; Mr. Robert M. Levy Manager Design Engineering Abex Corporation Signal-Stat Division P.O. Box 438 Somerset NJ 08873-3492; Dear Mr. Levy: This is in reply to your letter of February 25, 1985, to Frank Berndt the former Chief Counsel of this agency, asking for clarification of an interpretation of Safety Standard No. 108 that this agency furnished last year to Wesbar Corp.; On May 16, 1984, Wesbar asked whether the correct minimum effectiv luminous lens area on stop lamps and turn signal lamps was 8 square inches or 12 square inches, when intended for use on trailers whose overall width is 80 inches or greater. This office advised Wesbar on July 3, 1984, that as specified in SAE J586c for stop lamps and SAE J588e for turn signal lamps, the answer was 8 square inches. Your letter calls to our attention the fact that these SAE standards require each stop and turn signal lamp to have a minimum of 12 square inches in those vehicle configurations where two stop or turn signal lamps are mounted on the same side of the vehicle and are closer to each other than 22 inches.; Thank you for calling this oversight to our attention. Indeed, SA J586c and J588e establish this exception to the general minimum requirement of 8 square inches. We are furnishing a copy of this letter to Wesbar and apologize for any confusion that the earlier letter has caused.; Sincerely, Jeffrey R. Miller, Chief Counsel |
|
ID: aiam3169OpenMr. Thomas F. Brown, Mack Trucks, Engineering Division, P.O. Box 1761, Allentown, PA 18105; Mr. Thomas F. Brown Mack Trucks Engineering Division P.O. Box 1761 Allentown PA 18105; Dear Mr. Brown: This responds to your October 17, 1979, letter asking about the prope certification label for an intermediate manufacturer that alters the tires and rims on a chassis thereby affecting the gross axle and vehicle weight ratings. In your letter, you suggest an abbreviated certification label that would list the manufacturer's name and date of manufacture, and would make the statement that the vehicle will conform to certain standards if the incomplete vehicle document is followed. The agency agrees that this is a correct certification.; Intermediate manufacturers are required to attach labels to vehicle that they modify to indicate that some manufacturing operation has occurred on a vehicle between the manufacture of its chassis and its final manufacture. The intermediate manufacturer is permitted to select, from among a number of certification statements, the statement or statements that accurately represent the nature of the work undertaken by that manufacturer. Therefore, it is not necessary for an intermediate manufacturer to use all of the certification statements on its labels.; In the situation that you describe, the intermediate manufacturer wil make a statement on its label identical to one of the statements made by the chassis manufacturer. Although this appears to be redundant, it is necessary to have the intermediate manufacturer's label on the vehicle making the required certification statement so that a final-stage manufacturer can continue to rely upon the certification labels and upon the statements made in the incomplete vehicle document.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam3168OpenMr. Thomas F. Brown, Mack Trucks, Engineering Division, P.O. Box 1761, Allentown, PA 18105; Mr. Thomas F. Brown Mack Trucks Engineering Division P.O. Box 1761 Allentown PA 18105; Dear Mr. Brown: This responds to your October 17, 1979, letter asking about the prope certification label for an intermediate manufacturer that alters the tires and rims on a chassis thereby affecting the gross axle and vehicle weight ratings. In your letter, you suggest an abbreviated certification label that would list the manufacturer's name and date of manufacture, and would make the statement that the vehicle will conform to certain standards if the incomplete vehicle document is followed. The agency agrees that this is a correct certification.; Intermediate manufacturers are required to attach labels to vehicle that they modify to indicate that some manufacturing operation has occurred on a vehicle between the manufacture of its chassis and its final manufacture. The intermediate manufacturer is permitted to select, from among a number of certification statements, the statement or statements that accurately represent the nature of the work undertaken by that manufacturer. Therefore, it is not necessary for an intermediate manufacturer to use all of the certification statements on its labels.; In the situation that you describe, the intermediate manufacturer wil make a statement on its label identical to one of the statements made by the chassis manufacturer. Although this appears to be redundant, it is necessary to have the intermediate manufacturer's label on the vehicle making the required certification statement so that a final-stage manufacturer can continue to rely upon the certification labels and upon the statements made in the incomplete vehicle document.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam0582OpenMr. E. G. Nagle, Vice President - Automotive Sales, Allen Industries, Inc., Executive Offices: Honeywell Bldg., 17515 West Nine Mile Road, Southfield, MI, 48075; Mr. E. G. Nagle Vice President - Automotive Sales Allen Industries Inc. Executive Offices: Honeywell Bldg. 17515 West Nine Mile Road Southfield MI 48075; Dear Mr. Nagle: This is in reply to your letter of January 24, 1972, requestin information on possible changes to Motor Vehicle Safety Standard No. 302, 'Flammability of Interior Materials.'; At present, NHTSA is preparing an amendment to the standard based o the notice of proposed rulemaking published May 25, 1971 (36 F.R. 9565), and clarifying other questions pertaining to the standard that have been raised since its issuance. We hope to have this amendment prepared in the near future, but at present we cannot provide information on exact dates. At the same time, if the NHTSA determines that any changes in the standard made by the amendment require additional leadtime, appropriate action will be taken.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam0793OpenMr. Charles R. Matthews, Senior Safety Engineer, Oshkosh Truck Corporation, P. O. Box 560, Oshkosh, WI 54901; Mr. Charles R. Matthews Senior Safety Engineer Oshkosh Truck Corporation P. O. Box 560 Oshkosh WI 54901; Dear Mr. Matthews: This is in response to your letter of June 30, 1972, requestin information on a proper course of action to take concerning your placement of incorrect information on certification labels.; The placement of incorrect information of the type you describe (a overstatement of gross axle weight rating) may be a 'safety related defect' under the National Traffic and Motor Vehicle Safety Act. This would be the case if loading the vehicle to the specified rating would result in an unsafe operating condition.; Whether a defect exists is to be determined in the first instance b the vehicle manufacturer. If you determine that a defect exists, section 113 of the Act (15 U.S.C. 1402) requires that you notify first purchasers by certified mail, describing the defect, its effect on safety, and measures to be taken to correct it. The determination that a defect exists can also be made independently by NHTSA, which would then order the manufacturer to send the required notification. Regulations issued by NHTSA (Defect Reports, 49 CFR Part 573) require manufacturers of vehicles having safety defects to submit certain information to NHTSA, and to compile a list of affected owners.; Replacing the improper labels, as you have suggested, would be a appropriate action to take to rectify this situation and satisfy the Certification regulations.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam5461OpenMr. Tom Determan Engineering Manager Brownie Tank Mfg. Co. 1241 - 72nd Ave. N.E. Minneapolis, MN 55432; Mr. Tom Determan Engineering Manager Brownie Tank Mfg. Co. 1241 - 72nd Ave. N.E. Minneapolis MN 55432; Dear Mr. Determan: This is in reply to your letter of September 2 1994, to Taylor Vinson of this Office. You have inquired about the mounting height requirements specified in Motor Vehicle Safety Standard No. 108 for side marker lamps and reflex reflectors installed on tank trucks. You understand that 'side marker lamps must be mounted at any height above 15' from ground level, and reflex reflectors must be mounted between 15' and 60' from ground level.' You are correct. Standard No. 108 (Tables II and IV) specifies that side reflex reflectors on trucks shall be mounted not less than 15 inches nor more than 60 inches above the road surface, and that side marker lamps must be mounted not less than 15 inches above the road surface. This means that side marker lamps may be placed at heights greater than 60 inches. Noting your thought that enforcement personnel are mistakenly applying requirements for trailers to tank trucks of your customers, I would like to say that the requirements are the same for trailers, except that, under Table II which applies to trailers whose overall width is 80 inches or more, the rear side marker lamps are subject to the same 60-inch height limitation as the side reflex reflectors. I hope that this is helpful in resolving your problem. Sincerely, Philip R. Recht Chief Counsel; |
|
ID: aiam3507OpenMr. Katsuhiko Yokoi, Assistant Manager - Tech. Dept., Toyoda Gosei Co., Ltd., 1 Nagahata, Ochiai, Haruhi-mura, Nishikasugai-gun, Aichi-pref., 452 JAPAN; Mr. Katsuhiko Yokoi Assistant Manager - Tech. Dept. Toyoda Gosei Co. Ltd. 1 Nagahata Ochiai Haruhi-mura Nishikasugai-gun Aichi-pref. 452 JAPAN; Dear Mr. Yokoi: The answers to the questions in your letter of January 20, 1982, ar 'yes' to both questions.; >>>1. The 'adjacent layers' referenced in Federal Motor Vehicle Safet Standard (FMVSS) No. 106, paragraph S7.3.7, are (a) the inner tube and braided layer and (b) the braided layer and outer tube.<<<; >>>2. The adhesion requirements are met if both the tensile strength measured between (a) the inner tube and braided layer and (b) that between the braided layer and the outer cover are equal to or greater than 8lbs/inch as determined using the FMVSS No. 106 procedure. It should be noted that the 8lbs/inch value is an absolute minimum value as indicated in paragraph S8.6.4(a) of the standard.<<<; A copy of FMVSS No. 106 is included for your information. Sincerely, Vernon G. Bloom, Safety Standards Engineer |
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.