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: aiam2021OpenMr. Wade H. Barrineau, III, Compact Van Equipment Co., Inc., 5159 E. Shore Drive, Conyers, GA 30207; Mr. Wade H. Barrineau III Compact Van Equipment Co. Inc. 5159 E. Shore Drive Conyers GA 30207; Dear Mr. Barrineau: This is in response to your letter of July 17, 1975, inquiring as t the regulations to which you may be subject by manufacturing and selling interior shelving, interior safety bulkheads, and roof mounted ladder carriers for Ford Econoline vans.; The National Highway Traffic Safety Administration has issue regulations covering the alteration of completed, certified motor vehicles before their sale to a purchaser for purposes other than resale. (49 CFR SS 567.7 and 567.8, copy enclosed). Under these regulations, an alteration which either (1) invalidates a vehicle's existing weight ratings or (2) involves installation of other than 'readily attachable' components gives rise to a responsibility for affixing an alterer label, which identifies the alterer and contains some additional information.; From the description of your products, it appears that no specia expertise or tools are required for their installation. They would also seemingly not affect a vehicle's weight ratings. If this assessment is correct, we would accept as reasonable a manufacturer's determination that they are 'readily attachable', and that an alterer label is therefore not required when these products are installed.; The only Safety Standard that might apply to your products is Standar No. 302, *Flammability of Interior Materials* (copy enclosed).; In addition, as items of motor vehicle equipment, your products ar subject to the requirements of the National Motor Vehicle and Traffic Safety Act of 1966, as amended, and must therefore be free from safety-related defects.; If you have any further questions, feel free to write again. Sincerely, Frank A. Berndt, Acting Chief Counsel |
|
ID: aiam0340OpenAndrew R. Hricko, Esq., General Counsel, Insurance Institute for Highway Safety, Watergate Six Hundred, Washington, DC 20037; Andrew R. Hricko Esq. General Counsel Insurance Institute for Highway Safety Watergate Six Hundred Washington DC 20037; Dear Mr. Hricko: This is in reply to your letter of April 30, 1971, requesting a interpretation of the terms 'cooling system' and 'fuel system' as used in Motor Vehicle Safety Standard No. 215.; You first ask whether 'cooling system' includes the various component of the vehicle's air conditioning system. The term is not intended to include the air conditioning system.; Your second question is whether 'fuel systems' would include pollutio control vapor cannisters (sic) and other components used to reduce fuel emissions. If such components contain fuel or fuel vapor they are considered to be a part of the fuel system.; Please advise us if further clarification is needed. Sincerely, Lawrence R. Schneider, Acting Chief Counsel |
|
ID: aiam3468OpenMr. Don W. Upson, Colt Industries, Inc., 1901 'L' Street, N.W., Suite 303, Washington, DC 20036; Mr. Don W. Upson Colt Industries Inc. 1901 'L' Street N.W. Suite 303 Washington DC 20036; Dear Mr. Upson: This responds to your recent letter asking whether any Federa regulations apply to propane fuel systems designed for use in motor vehicles.; I am enclosing an information sheet which sets forth the implication under Federal law of converting gasoline-powered vehicles to use propane or other gas, as well as a general discussion of auxiliary fuel tanks. From that discussion, you will see that there are no safety standards directly applicable to propane fuel tanks as pieces of automobile equipment. There are, however, specifications under the Bureau of Motor Carrier Safety regulations relating to propane fuel systems on commercial vehicles or to tanks used for shipment of propane gas in interstate commerce. If your tanks will be used on other than private vehicles, these regulations may be of interest to you. For further information, you may contact Mr. W. R. Fiste of the Bureau of Motor Carrier Safety (202-426-0033).; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam3587OpenMr. Ronald E. DeVolder, Vice President, Roberts Motor Company, 550 N.E. Columbia Boulevard, Portland, OR 97211; Mr. Ronald E. DeVolder Vice President Roberts Motor Company 550 N.E. Columbia Boulevard Portland OR 97211; Dear Mr. DeVolder: This is in reply to your letter of July 16, 1982, asking for a interpretation of Motor Vehicle Safety Standard No. 108.; You enclose photos of a 1982 Kenworth truck which has two pairs o front turn signal lamps: one set (incorporating a side reflector) mounted 58 1/2 inches above the road surface and which are 83 inches apart, the other, mounted approximately 81 1/2 inches above the road surface and which are 110 inches apart. You have asked whether the vehicle would comply if the lower mounted set were removed and an amber reflex reflector placed on each side of the fender as far forward as practicable.; The answer is yes. The mounting height of 81 1/2 inches does not excee the limit of 83 inches imposed by Table II of Standard No. 108. In addition, the lamps appear to meet the two further requirements that they be located as far apart as practicable and at the same height.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam1967OpenMr. James J. Schintz, Managing Director, Pennsylvania Independent Automobile Dealers Association, 229 State Street, Harrisburg, PA 17101; Mr. James J. Schintz Managing Director Pennsylvania Independent Automobile Dealers Association 229 State Street Harrisburg PA 17101; Dear Mr. Schintz: You (sic) letter of April 21, 1975, to the Federal Trade Commissio concerning the validity of an enclosed odometer disclosure form has been forwarded to this office for reply.; The odometer mileage disclosure portion of the East End Motors' sale contract does not satisfy the requirements of the odometer disclosure regulation (49 CFR Part 580). In order to fulfill the requirements, the following information must be added: the vehicle identification number, the vehicle's last plate number, the vehicle transferor's address, the date of the disclosure statement, a reference to the Motor Vehicle Information and Cost Savings Act (Pub. L. 92-513) and the liability it imposes, and a statement, if applicable, that the vehicle's actual mileage differs from the odometer reading for reasons other than odometer calibration error and the actual mileage is unknown.; Failure to include all of the above information on the odomete disclosure statement executed at the time ownership of a vehicle is tranferred (sic) constitutes a violation of section 408 of the Cost Savings Act and may make the violator liable in the amount of $1,500 or treble damages.; For your information I have enclosed copies of the relevant portions o the Act and the disclosure requirements. You will note that S 580 of the regulation contains a sample odometer mileage statement. Incorporation of this format into a sales contract would satisfy the Federal requirements.; Sincerely, James C. Schultz, Chief Counsel |
|
ID: aiam0851OpenR. F. Tifft, Purchasing Agent, Bunker Ramo, Borg Instruments Division, 902 Wisconsin Street, Delavan, WI, 53115; R. F. Tifft Purchasing Agent Bunker Ramo Borg Instruments Division 902 Wisconsin Street Delavan WI 53115; Dear Mr. Tifft: This is in reply to your letter of September 6, 1972, inquiring abou the applicability of Federal Motor Vehicle Safety Standard (FMVSS) No. 302 to the lens or crystal of automobile clocks installed in the instrument panel of a car.; The lens or crystals of automobile clocks are not included unde paragraph S4.1 as interior components subject to the standard, and, accordingly, they do not have to meet the requirements of FMVSS No. 302.; Sincerely, Robert L. Carter, Associate Administrator, Motor Vehicl Programs; |
|
ID: aiam1765OpenMr. Oliver C. Nusslock,Cooper Industrial Products, Inc.,725 West 11th Street,Auburn Indiana 46706; Mr. Oliver C. Nusslock Cooper Industrial Products Inc. 725 West 11th Street Auburn Indiana 46706; Dear Mr. Nusslock:#Please forgive the delay in responding to you letter of October 24, 1974, requesting information on the requirements of Federal Motor Vehicle Safety Standard No. 106-74, as applied to light duty vacuum hose.#If you manufacture vacuum hose for use in brake systems, you must ensure that the hose meets the performance requirements of Standard No. 106-74, as well as the labeling requirements. I have enclosed a copy of the standard, a copy of the most recent amendment (39 FR 39725), and an information sheet entitled 'Where to Obtain Motor Vehicle Safety Standards and Regulations'.#The system of staggered effective dates is as follows: All brake hoses and brake hose end fittings manufactured after September 1, 1974, must conform to the standard. All brake hose assemblies manufactured after March 1, 1975, must conform to the standard. All vehicles manufactured after September 1, 1975, must contain only hose and assemblies which conform to the standard.#Please let us know if you have any further question.#Yours truly,Richard B. Dyson,Acting Chief Counsel; |
|
ID: aiam2167OpenMr. LeRoy E. Mueller, President, Wisconsin Trailer Company, Inc., Richfield, WI 53076; Mr. LeRoy E. Mueller President Wisconsin Trailer Company Inc. Richfield WI 53076; Dear Mr. Mueller: This responds to your November 26, 1975, request for confirmation tha the NHTSA permits the establishment of gross axle weight ratings (GAWR) for trailer axles based on use at a speed of less than 60 mph.; Your interpretation is incorrect. In the April 28, 1975, interpretatio letter to Mr. James Srch that was enclosed in the NHTSA's recent letter to you, it was stated that '. . .NHTSA has found it necessary to specify that GAWR's and GVWR's be calculated on the basis of highway speeds and not qualified by reduced speed ratings. . . .'; Since the NHTSA's November 20, 1975, letter to you, the agency ha published a proposal that would amend the definition of GAWR to conform to this interpretation. A copy is enclosed for your information.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam2163OpenMr. LeRoy E. Mueller, President, Wisconsin Trailer Company, Inc., Richfield, WI 53076; Mr. LeRoy E. Mueller President Wisconsin Trailer Company Inc. Richfield WI 53076; Dear Mr. Mueller: This responds to your November 26, 1975, request for confirmation tha the NHTSA permits the establishment of gross axle weight ratings (GAWR) for trailer axles based on use at a speed of less than 60 mph.; Your interpretation is incorrect. In the April 28, 1975, interpretatio letter to Mr. James Srch that was enclosed in the NHTSA's recent letter to you, it was stated that '. . .NHTSA has found it necessary to specify that GAWR's and GVWR's be calculated on the basis of highway speeds and not qualified by reduced speed ratings. . . .'; Since the NHTSA's November 20, 1975, letter to you, the agency ha published a proposal that would amend the definition of GAWR to conform to this interpretation. A copy is enclosed for your information.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam1213OpenMr. Francois Louis,Manager,Technical Standards Department,Renault, Inc.,100 Sylvan Avenue,Englewood Cliffs, New Jersey 07632; Mr. Francois Louis Manager Technical Standards Department Renault Inc. 100 Sylvan Avenue Englewood Cliffs New Jersey 07632; Dear Mr. Louis:#This is in reply to your letter of August 1, 1973 asking for clarification of S5.2.1 and S6.9 of Standard No. 105a.#You interpret the parking brake test as allowing 'the vehicle to slide down the 30% incline (because of its weight) as long the wheels remain locked'. The parking brake must hold the vehicle on a 30% grade for 5 minutes. If vehicle weight distribution is such that the limit of traction is exceeded and the vehicle slides down the incline, no noncompliance would be indicated unless the parking brake failed to lock the wheels.#No skid number is specified for the 'clean, dry, smooth, portland cement concrete' incline surface specified in S6.9.#Yours truly,Richard B. Dyson,Assistant Chief Counsel; |
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.