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: nht90-4.36OpenTYPE: Interpretation-NHTSA DATE: October 8, 1990 FROM: William Walters TO: Erika Jones -- Chief Counsel, NHTSA TITLE: None ATTACHMT: Attached to article entitled Dankert's Device, Local inventor wants to produce Info-Lite (text omitted); Also attached to United States Patent information for patent number 4,922,225 (text and graphics omitted) TEXT: I am concerned why the D.O.T. and the National Safety Council have not investigated the enclosed material. The original 3rd brake lite patent and the one adopted for mandatory use was designed by Norman Dankert. His addition which is covered by the enclosed patent not only addressed highway problems but gives you the solution. This safety is before the fact , not after as is the case of ABS & Air Bags. Why not prevent the occurance. This lite also becomes the ultimate flow meter which prevents "bunching" and congestion. Please read the enclosed, "Correcting the Path-Following message." The United States Patent Office came to the conclusion that the analysis merited a patent. I would like the National Safety Administration's opinion on this and also the reason why this System is not being used. Attachments Attached is an article entitled Dankert's Device, Local inventor wants to produce Info-Lite (text omitted); Also attached is United States Patent information, patent number 4,922,225, dated May 1, 1990, (text and graphics omitted). |
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ID: nht89-3.42OpenTYPE: Interpretation-NHTSA DATE: November 21, 1989 FROM: Patrick S. Baran -- Inventors, Dreamers, Explorers & Artists Inc. TO: Taylor Vinson -- U.S. Dept. of Transportation.,NHTSA TITLE: None ATTACHMT: Attached to letter dated 4-9-90 To Patrick S. Baran and From Stephen P Wood; (A35; STD 108 & 218); Also attached to letter 8-2-82 To William R. Harris, Jr. and From Frank Berndt; Attachment SAEJ586c not included. TEXT: We have a brake light for the back of a motor cycle helmet. I am writing to you for informations on the D.O.T. guidelines for tail light brightness. If there is anything else you can think of that we need to know for D.O.T. approval of this helmet brake light please let us know. I can be reached at(312)883-9200 or mail the information to I.D.E.A. Inc.; 2340 West Belmont; Chicago, IL 60618. Thank you for your time. |
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ID: nht95-5.9OpenTYPE: INTERPRETATION-NHTSA DATE: December 22, 1995 FROM: Samuel J. Dubbin -- Chief Counsel, NHTSA TO: Kenneth W. Easterling -- Plan B Engineering, Inc. TITLE: NONE ATTACHMT: 11/16/95 letter from Kenneth W. Easterling to Taylor Vinson (OCC 11372); 7/30/93 letter from John Womack to Wayne Ferguson TEXT: This responds to your letter of November 16, 1995, asking for our opinion of "G-Lamps", ("proportional deceleration indicator lamps) intended as a rear end collision avoidance device. Your system would flash the stop lamps proportionally to the rate of deceleration. Over the years, the agency has received many requests for interpretations of the laws which it administers as they relate to deceleration warning systems. Our reply has been that it is impermissible to wire the stop lamp system so that it flashes, no ma tter what the purpose of the flashing. I enclose for your information, as a representative reply, a copy of our letter of July 30, 1993, to Wayne Ferguson of the Virginia Department of Transportation, which fully sets forth our views and interpretations . If you have questions about these matters, you may telephone Taylor Vinson of this office at 202-366-5263. Enclosure: (see 7/30/93 letter from John Womack to Wayne Ferguson) |
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ID: nht95-7.64OpenTYPE: INTERPRETATION-NHTSA DATE: December 22, 1995 FROM: Samuel J. Dubbin -- Chief Counsel, NHTSA TO: Kenneth W. Easterling -- Plan B Engineering, Inc. TITLE: NONE ATTACHMT: 11/16/95 letter from Kenneth W. Easterling to Taylor Vinson (OCC 11372); 7/30/93 letter from John Womack to Wayne Ferguson TEXT: This responds to your letter of November 16, 1995, asking for our opinion of "G-Lamps", ("proportional deceleration indicator lamps) intended as a rear end collision avoidance device. Your system would flash the stop lamps proportionally to the rate of deceleration. Over the years, the agency has received many requests for interpretations of the laws which it administers as they relate to deceleration warning systems. Our reply has been that it is impermissible to wire the stop lamp system so that it flashes, no matter what the purpose of the flashing. I enclose for your information, as a representative reply, a copy of our letter of July 30, 1993, to Wayne Ferguson of the Virginia Department of Transportation, which fully sets forth our views and interpretations. If you have questions about these matters, you may telephone Taylor Vinson of this office at 202-366-5263. Enclosure: (see 7/30/93 letter from John Womack to Wayne Ferguson) |
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ID: nht72-6.10OpenDATE: 02/22/72 FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA TO: Winnebago Industries Inc. TITLE: FMVSR INTERPRETATION TEXT: We have received your quarterly report pursuant to section 573.5 of the Defect Reports regulations and note that you have marked "confidential" data submitted concerning a notification campaign conducted on your Model 04 motor home. The NHTSA does not consider information regarding notification campaigns to be confidential under sections 112 or 113 of the National Traffic and Motor Vehicle Safety Act (15 U.S.C. @ 1401, 1402), and is making this information public. The only information that we have agreed to keep confidential, if requested, are production figures submitted pursuant to section 573.5(b). |
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ID: nht80-1.1OpenDATE: 01/03/80 FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA TO: Mr. Glen Brinks TITLE: FMVSR INTERPRETATION TEXT: This responds to your recent letter requesting information concerning the Federal safety regulations applicable to motorcycle fuel tanks and motorcycle trailers. The Federal Motor Vehicle Safety Standard regarding fuel system intergrity, Standard No. 301-75, currently does not apply to motorcycles. Two safety standards would be applicable to the manufacture of motorcycle trailers: Safety Standard No. 108, Lamps, Reflective Devices, and Associated Equipment and Safety Standard No. 120, Tire Selection and Rims for Vehicles Other Than Passenger Cars. The manufacturer of a trailer, including a motorcycle trailer, would have to certify the compliance of the trailer to these two safety standards. Part 566 of our regulations, Manufacturer Identification (49 CFR 566), specifies information which must be submitted to the NHTSA by manufactures of motor vehicles, including trailers. Part 567, Certification (49 CFR 567), specifies the content and location of the certification label or tag that must be attached to motor vehicles regulated by our standards. I am enclosing an information sheet that explains where you can obtain copies of these safety standards and regulations. ENC. November 23, 1979 Joseph Levin NHTSA Dear Mr. Levin; Some time ago, you were a big help to me when I was working on a kit car article for Road & Track magazine. Currently, I am working on another project requiring a knowledge of NHTSA regulations and I wonder if you could help out again. Could you send me a copy of the NHTSA regulations relating to 1) motorcycle fuel tank construction, type of fittings required, fuel lines, etc. and 2) motorcycle trailers? Thank you very much for your consideration. Glenn Brinks |
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ID: nht94-3.20OpenTYPE: INTERPRETATION-NHTSA DATE: June 3, 1994 FROM: John Womack -- Acting Chief Counsel, NHTSA TO: John A. Griffiths TITLE: None ATTACHMT: Attached To Letter Dated 5/16/94 From John A. Griffiths (OCC-10024) TEXT: Dear Mr. Griffiths: This responds to your request for an interpretation whether the Federal Motor Vehicle Safety Standards specify for a manual transmission vehicle, a "neutral safety switch," or other means to prevent starting of the vehicle unless the clutch is fully depr essed. The answer is no. Standard No. 102, Transmission shift lever sequence, starter interlock, and transmission braking effect, specifies starter interlocks for automatic transmission vehicles, but not for manual transmission vehicles. (See S3.1.3.) None of the other safety s tandards specify that motor vehicles include a device of the type you describe, or specify means to prevent starting of a manual transmission vehicle unless the clutch is depressed. I hope that this information is useful. If you have any further questions, please contact Dorothy Nakama of my staff at (202) 366-2992. Sincerely, |
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ID: 11372Open Mr. Kenneth W. Easterling Dear Mr. Easterling: This responds to your letter of November 16, 1995, asking for our opinion of "G-Lamps", ("proportional deceleration indicator lamps) intended as a rear end collision avoidance device. Your system would flash the stop lamps proportionally to the rate of deceleration. Over the years, the agency has received many requests for interpretations of the laws which it administers as they relate to deceleration warning systems. Our reply has been that it is impermissible to wire the stop lamp system so that it flashes, no matter what the purpose of the flashing. I enclose for your information, as a representative reply, a copy of our letter of July 30, 1993, to Wayne Ferguson of the Virginia Department of Transportation, which fully sets forth our views and interpretations. If you have questions about these matters, you may telephone Taylor Vinson of this office at 202-366-5263. Sincerely,
Samuel J. Dubbin Chief Counsel Enclosure ref:108 d:12/22/95 |
1995 |
ID: 77-1.36OpenTYPE: INTERPRETATION-NHTSA DATE: 03/04/77 FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA TO: Harman International Industries, Inc. TITLE: FMVSS INTERPRETATION |
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ID: nht68-1.33OpenDATE: 10/23/68 FROM: AUTHOR UNAVAILABLE; James B. Gregory; NHTSA TO: National Association of Independent Insurers A.J.J. Enterprises Inc. NHTSA TITLE: FMVSS INTERPRETATION FMVSR INTERPRETATION |
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.