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: morr.jegOpen Ms. Sarah L. Morrissey Dear Ms. Morrissey: This responds to your faxed letter concerning air bag regulations. I apologize for the delay in our response. You asked what specific governmental regulations were in effect regarding air bags in a 1994 Plymouth Voyager. You also asked whether the Voyager is considered a car or light truck. The National Highway Traffic Safety Administration's regulations related to air bags are included in Federal Motor Vehicle Safety Standard No. 208, Occupant Crash Protection. The safety standards that apply to a vehicle depend on its date of manufacture. I am enclosing a copy of Standard No. 208 revised as of October 1, 1993. This corresponds to the early part of the 1994 model year. For purposes of our safety standards, the Plymouth Voyager was classified as a multipurpose passenger vehicle. I note that the term "light truck" is commonly used to refer to trucks, buses, and multipurpose passenger vehicles with a gross vehicle weight rating of 10,000 pounds or less. For further information about air bags and related rulemakings, you may wish to visit our web site at http://www.nhtsa.dot.gov and select the term "Air bags" under the Popular Information column. Sincerely, |
1997 |
ID: nht75-6.27OpenDATE: 08/18/75 FROM: FRANK A. BERNDT -- NHTSA ACTING CHIEF COUNSEL TO: WALTER C. BURVILLE -- MANAGER, UNDERWRITING SURVEY DEPARTMENT CHUBB/PACIFIC INDEMNITY GROUP TITLE: N40-30 ATTACHMT: ATTACHED TO LETTER DATED 7/18/75 FROM WALTER C. BURVILLE OF CHUBB PACIFIC INDEMNITY GROUP TO THE ASSOCIATE ADMINISTRATOR FOR MOTOR VEHICLE PROGRAMS NHTSA TEXT: Dear Mr. Burville: This responds to your July 18, 1975, question whether actual road testing of completed vehicles that are required to meet Standard No. 121, Air Brake Systems, is necessary as a basis of certification to the standard. I have enclosed copies of two letters that discuss in detail the kind of evidence a manufacturer of vehicles might use to certify compliance with Standard No. 121. It is emphasized in the letters that the statutory requirement is the exercise of "due care" and that this term may have a different meaning in the case of a small manufacturer than in the case of a large manufacturer. The manufacturer may decide to run only one test of his vehicles, or he may test representative vehicles periodically. I have also enclosed a copy of a letter to a California manufacturer of trailers which may be the source of the NHTSA opinion that one means of exercising "due care" might be tests of representative trailers. Sincerely, ENCLOSURES |
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ID: nht75-5.1OpenDATE: 04/28/75 FROM: NOEL C. BUFE FOR JAMES B. GREGORY -- NHTSA TO: Hendrickson Manufacturing Company TITLE: FMVSR INTERPRETATION TEXT: I am writing in response to your letter of March 25, 1975, in which you request advice as to whether you should establish gross axle weight ratings and gross vehicle weight ratings based on the 55 mph national speed limit or on the maximum attainable speed of the vehicle. The Cross Axle Weight Rating (CAWR) and the Cross Vehicle Weight Rating (CVWR) are defined by the National Highway Traffic Safety Administration (NHTSA) as determinations made by the manufacturer. (49 CFR 3571.3). As a general matter NHTSA finds that the manufacturer is most familiar with the complexities of this product and is most qualified to assign these values. Recently NHTSA has found it necessary to specify that CAWR's and CVWR's be calculated on the basis of highway speeds and not qualified by reduced speed ratings; our reasons for this action are contained in the enclosed letter. For purposes of CAWR-CVWR calculations, NHTSA will hencefort consider "highway speed" to be the 60 mph value used by the United States Tire and Rim Association in assigning unqualified ratings to their tires. Therefore, your trucks and buses which are capable of speeds of 60 mph or more should be assigned ratings which reflect vehicle capabilities at 60 mph. |
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ID: nht72-1.25OpenDATE: 05/26/72 FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA TO: Livingston's Tire Shop TITLE: FMVSS INTERPRETATION TEXT: This is in reply to your letter of May 2, 1972, requesting a letter from NHTSA to the effect that tire manufacturers are free to sell you new repairable tires which you plan to repair and sell. We have assumed that the manufacturers of the tires do not believe that they conform to Motor Vehicle Safety Standard No. 109. "New Pneumatic Tires," and that they have not certified conformance to the standard, as this is apparently the reason for their reluctance to sell you these tires. Paragraph S6. of Standard No. 109 provides, among other things, that passenger car tires that are not certified, defined as "reclassified tires," must bear a label (specified in the standard) stating that they are not to be sold for use on passenger cars. If you wish to purchase reclassified tires, repair them, and resell them for passenger car use, you must ensure that they conform to the performance requirements of Standard No. 109 (paragraphs S1. through S5.), and relabel and certify them in accordance with paragraph S4.3. You should be aware that the NHTSA has proposed, in a notice dated November 27, 1971 (36 F.R. 22688, copy enclosed) to prohibit the sale for any purpose of reclassified tires. |
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ID: nht80-1.21OpenDATE: 03/03/80 FROM: AUTHOR UNAVAILABLE; Debra Weiner; NHTSA TO: Delta Inc. of Arkansas TITLE: FMVSR INTERPRETATION TEXT: Please find enclosed copies of letters concerning the legal implications of manufacturing and installing automotive auxiliary fuel tanks. In addition to the enclosed material, please note that a person who goes into the business of manufacturing motor vehicle equipment, such as auxiliary fuel tanks, is required to submit identifying information and a description of the items he produces to this agency in accord with 49 CFR Part 566 (copy enclosed). I hope that you will find the enclosed materials helpful. If you have any further questions, please feel free to call me at 202-426-2992. ENCLS. |
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ID: nht72-5.7OpenDATE: 03/30/72 FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA TO: Schetky Equipment Corporation TITLE: FMVSR INTERPRETATION TEXT: This is in reply to your letter of March 16, 1972, in which you request clarification of the Certification requirements (49 CFR Part 567). You ask whether certification is necessary, mentioning specifically certification to Motor Vehicle Safety Standard No. 108, when you install new dump bodies on used chassis manufactured both before and after January 1, 1968. The motor vehicle safety standards apply only to new vehicles, and neither compliance with the standards nor "Certification" is required if you are installing truck bodies on used chassis. We are pleased to be of assistance. |
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ID: nht69-2.7OpenDATE: 01/13/69 FROM: AUTHOR UNAVAILABLE; Clue D. Ferguson; NHTSA TO: Baycraft TITLE: FMVSS INTERPRETATION TEXT: Your letter of December 2, 1968, to Mr. William L. Hall, concerning safety glazing in canopies, has been referred to me for reply. FHWA Ruling 68-1 clarified the requirement that slide-in campers must comply with Standard 205 since they are items of motor vehicle equipment for use in motor vehicles. A copy of FHWA Ruling 68-1 is enclosed. The same rationale applies to your canopies. Forward facing windows must be laminated safety glass meeting the requirements of Test No. 26 of ASA Standard Z26.1-1966, July 15, 1966. Other windows may be AS1, 2, 3, 4, 5, 6, 7, 10, 11, 2-26, or 3-26. |
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ID: nht71-3.2OpenDATE: 05/14/71 FROM: AUTHOR UNAVAILABLE; C. A. Baker for E. T. Driver; NHTSA TO: J. A. Kackney & Sons, Inc. TITLE: FMVSS INTERPRETATION TEXT: This is in reply to your letter of May 3, 1971, to Mr. Julian E. Leycath of this Administration, concerning the installation of supplementary stop and rear turn signal lamps on your van type delivery bodies. Installation of the supplementary stop and rear turn signal lamps, in the manner described in your letter and as shown on your drawings 69C-81, and 69C-41 (enclosed with your letter). would not impair the effectiveness of lamps, reflective devices, and associated equipment required by Federal Motor Vehicle Safety Standard No. 108 and would not be prohibited by that standard. Standard No. 108 presently specified that the required stop lamps be mounted at a height "not less than 15 inches nor more than 72 inches". No mounting heights are presently specified for the required rear turn signal lamps. Effective January 1, 1972, the mounting height of required rear turn signal lamps will be "not less than 15 inches nor more than 83 inches". These limitations on mounting heights for the required lamps are not applicable to supplementary stop and rear turn signal lamps. |
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ID: nht94-1.56OpenTYPE: Interpretation-NHTSA DATE: February 14, 1994 FROM: Daniel T. Mason -- Product Development Engineer, Automotive Division, Avery Dennison TO: Barbara Gray -- Office of Market Incentives, NHTSA TITLE: None ATTACHMT: Attached to letter dated 4/8/94 from John Womack to Daniel T. Mason (A42; Part 541) TEXT: The purpose of this letter is to ask for a ruling of the footprint requirements of the parts marking legislation, 541-Federal Motor Vehicle Theft Prevention Standard. I am a Product Development Engineer working under Cliff Nastas for Avery Dennison. My question refers to the footprint feature of the label that appears under a UV light in the substrate after the label (illegible words). Both Avery Dennison and (illegible word) supply parts marking labels to the automotive industry. Both have a florescent agent that migrates into the substrate once applied. Would a label that substitutes a florescent copy of the VIN instead of the whol e footprint of the label be in compliance to the federal legislation? Please inquire for a ruling on this. I will follow up this letter with a phone call to discuss any questions you may have in the next couple weeks. |
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ID: nht90-4.83OpenTYPE: Interpretation-NHTSA DATE: December 13, 1990 FROM: Paul Jackson Rice -- Chief Counsel, NHTSA TO: M. Iwase -- General Manager, Technical Administration Department, Koito Mfg. Co. Ltd. TITLE: None ATTACHMT: Attached to letter dated 11-20-90 to Paul Jackson Rice from M. Iwase (OCC 5458) TEXT: This is in response to your letter of November 20, 1990 with respect to "interpretation and/or petition" concerning combination headlighting systems. Koito has asked about the permissibility of two or four lamp headlighting systems in which the upper beam would be provided by integral beam headlamps, and the lower beam by replaceable bulb headlamps. The systems you describe would not be permissible under Standard No. 108, which allows only the three types of headlighting systems that you mention. Integral beam headlighting systems must be comprised of integral beam headlamps which, by definition, a re headlamps other than sealed beam or replaceable bulb headlamps. Replaceable bulb headlighting systems are those that incorporate the standardized replaceable light sources listed in Standard No. 108. We are transmitting your request to the Office of Rulemaking, for consideration as a petition for rulemaking. |
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.