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: aiam2670OpenMr. M. J. Denholm, Director of Engineering, Power Controls Division, Midland-Ross Corporation, 490 South Chestnut Street, Owosso, MI 48867; Mr. M. J. Denholm Director of Engineering Power Controls Division Midland-Ross Corporation 490 South Chestnut Street Owosso MI 48867; Dear Mr. Denholm: This responds to Midland-Ross' July 8, 1977, request for confirmatio that the requirement that '[e]ach service reservoir system shall be protected against loss of air pressure. . .by check valves or equivalent devices' in S5.1.2.3 and S5.2.1.5 of Standard No. 121, *Air Brake Systems*, permits small losses of air pressure through the check valve of up to 2 psi per minute without constituting noncompliance.; The requirement for protection against 'loss of air pressure' doe permit a small amount of leakage, in recognition of the fact that no fitting can be perfectly air tight. While the standard does not presently specify a rate of permissible air loss in S5.1.2.3 or S5.2.1.5, the agency has adopted a maximum loss of 10 psi in 10 minutes as meeting the requirement for protection against loss of air pressure. The agency is considering adding such a specification to the standard in the future by interpretive amendment.; Sincerely, Joseph J. Levin, Jr., Chief Counsel |
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ID: aiam5270OpenMr. Herman Myburgh Executive Vice-President Allvan Corporation; Mr. Herman Myburgh Executive Vice-President Allvan Corporation; FAX 1-615-459-0289 Dear Mr. Myburgh: This responds to your FAX o November 8, 1993, asking for an interpretation of the conspicuity mounting height requirement of Standard No. 108 as it applies to your curtainsided trailer. You state that there are no retroreflective tapes that can be affixed to the curtain material itself and ask whether the conspicuity material may be placed on the frame rail. The answer is yes. As you note, in that location the material will be located within the range of mounting heights specified in recent amendments to Standard No. 108. For your information, submissions to the docket during the course of this rulemaking indicate that there are conspicuity materials that can be affixed to curtain materials. Some trailer manufacturers may prefer this avenue to compliance. Sincerely, John Womack Acting Chief Counsel; |
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ID: aiam0076OpenChester G. Parsons, President, Elgin Sweeper Company, 1300 West Bartlett Road, Elgin, IL 60120; Chester G. Parsons President Elgin Sweeper Company 1300 West Bartlett Road Elgin IL 60120; Dear Mr. Parsons: This is in response to your letter of April 17 requesting eithe confirmation of your opinion that it was 'not the intent of the Federal Motor Vehicle Safety Standards to apply to' the three wheeled motor street sweeper manufactured by Elgin, or, in the alternative, consideration by the Federal Highway Administration of the establishment of a separate classification for these vehicles.; Three wheeled motor street sweepers are 'motor vehicles' within th meaning of the National Traffic and Motor Vehicle Safety Act of 1966. However, they do not fall into any of the vehicle types defined thus far, to which standards are applicable, and consequently there are no standards applicable to it at this time.; Sincerely, William Hadden, Jr., M.D. |
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ID: aiam5629OpenJonathan P. Reynolds, Esq. Cosco, Inc. 2525 State St. Columbus, IN 47201; Jonathan P. Reynolds Esq. Cosco Inc. 2525 State St. Columbus IN 47201; "Dear Mr. Reynolds: This responds to your letter asking us to confir that we consider your submission, dated August 3, 1995, as a timely petition for reconsideration of a final rule published July 6, 1995 (Docket No. 74-09, Notice 42). You enclosed a copy of a Federal Express document to show that your submission was received by NHTSA within the time period provided for such petitions under 49 CFR 553.35. The Federal Express document, which shows the signature of an agency employee, supports a finding that your submission was timely filed. NHTSA is processing your submission as a petition for reconsideration of the subject rule. If you have any further questions about your petition, please contact Ms. Deirdre Fujita of my staff at (202) 366-2992. Sincerely, John Womack Acting Chief Counsel"; |
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ID: aiam0548OpenMr. H. Braun, Engineering Supervisor - Production, Motor Coach Industries, Inc., Pembina, ND 58271; Mr. H. Braun Engineering Supervisor - Production Motor Coach Industries Inc. Pembina ND 58271; Dear Mr. Braun: This is in reply to your letter of October 23, 1972, in which you as whether it is permissible under the Certification regulations for you to list alternative tire sizes and gross axle weight ratings on certification labels for vehicles which you sell without tires, but on which you apparently install them before delivery. You indicate that the tires are supplied by the customer, which he either owns, leases, or purchases from you.; Under the Certification regulation, you may if you wish lis alternative tire sizes, and alternative gross vehicle or gross axle weight ratings, as you described in your letter. If you install the tires, regardless of whether they are owned by the vehicle purchaser, leased, or purchased from you, the tire you install should be one of the alternative sizes listed on the certification label.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam0554OpenMr. H. Braun, Engineering Supervisor - Production, Motor Coach Industries, Inc., Pembina, ND 58271; Mr. H. Braun Engineering Supervisor - Production Motor Coach Industries Inc. Pembina ND 58271; Dear Mr. Braun: This is in reply to your letter of October 23, 1972, in which you as whether it is permissible under the Certification regulations for you to list alternative tire sizes and gross axle weight ratings on certification labels for vehicles which you sell without tires, but on which you apparently install them before delivery. You indicate that the tires are supplied by the customer, which he either owns, leases, or purchases from you.; Under the Certification regulation, you may if you wish lis alternative tire sizes, and alternative gross vehicle or gross axle weight ratings, as you described in your letter. If you install the tires, regardless of whether they are owned by the vehicle purchaser, leased, or purchased from you, the tire you install should be one of the alternative sizes listed on the certification label.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam1527OpenMr. Tatsuo Kato,Nissan Motor Co., Ltd.,560 Sylvan Avenue,Englewood Cliffs, New Jersey 07632; Mr. Tatsuo Kato Nissan Motor Co. Ltd. 560 Sylvan Avenue Englewood Cliffs New Jersey 07632; Dear Mr. Kato:#This responds to your July 3, 1974, question whether th Standard No. 106-74, *Brake hoses*, labeling requirements for brake hose fittings (S5.2.3) permit labeling in addition to that required in the section.#Optional labeling is not prohibited by the standard as long as the additional marking does not confuse the required marking. We have already interpreted S5.2.2 to permit optional labeling on the opposite side of the hose from the required labeling. The required labeling must appear without additions to make it clearly legible.#Your illustration appears satisfactory as long as the '1/8' and the 'lot number are sufficiently separate for clarity. #Yours truly,Richard B. Dyson,Acting Chief Counsel; |
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ID: aiam1979OpenMr. David J. Humphreys, RVIA, 1140 Connecticut Avenue, Washington, DC 20036; Mr. David J. Humphreys RVIA 1140 Connecticut Avenue Washington DC 20036; Dear Mr. Humphreys: This is in response to your letter of May 22, 1975, in which yo request an interpretation which excludes roof vent covers in recreational vehicles from the coverage of Motor Vehicle Safety Standard No. 205.; The National Highway Traffic Safety Administration (NHTSA) has receive an identical request from Richards, WAtson, Dreyfuss & Gershon on behalf of Hehr International, Inc. In response to that request, we have determined that roof vent covers should be included within the scope of Standard No. 205, but also concur that roof vent covers manufactured by the injection molding process are not susceptible to testing under the procedures found in USAS Z26.1. Consequently, we intend to issue in the near future proposed rulemaking which would establish surrogate testing procedures for this type of roof vent cover. Until such time as the new procedure is adopted, it is the intention of the NHTSA to take no action against manufacturers who do not certify that their injection molded roof vent covers meet the requirements of Standard No. 205 which incorporate the requirements of USAS Z26.1.; Sincerely, James C. Schultz, Chief Counsel |
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ID: aiam1224OpenMr. Jim Peters, Florida Department of Agriculture & Consumer Services, Tallahassee, FL 32304; Mr. Jim Peters Florida Department of Agriculture & Consumer Services Tallahassee FL 32304; Dear Mr. Peters: This is in response to your request of July 18, 1973, that the Nationa Highway Traffic Safety Administration undertake an investigation of possible odometer tampering on a vehicle purchased by Mr. Fulton Y. Roberts of Tallahassee.; There are no criminal penalties for violation of the odomete requirements of the Motor Vehicle Information and Cost Savings Act. Remedies for violation of the odometer requirements are of two types. In the case of repeated violations, the United States Attorney may seek injunctive relief against further violations. In the case of a violation which has already occurred, the remedy is a private civil action by the defrauded party. For this reason, the NHTSA does not normally investigate incidents such as this.; Mr. Roberts should be advised that he may be able to sue for $1,50 without proof of damages, or possibly more if he can prove damages.; Mr. Roberts may wish to consult an attorney in this matter. Th applicable provisions of the Act are enclosed.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam2286OpenMr. Gilbert Theissen,6S Hayden Hall,33 Washington Square West,New York, New York 10011; Mr. Gilbert Theissen 6S Hayden Hall 33 Washington Square West New York New York 10011; Dear Mr. Theissen:#This is in response to your letter of February 5 1976, to Mrs. Winifred Desmond of this agency concerning braking and rollover characteristics of the Jeep vehicle. We are sorry for the delay in our answer.#The Jeep Corporation is correct in saying that 49 CFR 571.105-75, *Hydraulic Brake Systems*, applies only to passenger cars. It will also apply to school buses manufactured after October 25, 1976. Part 575, Consumer Information Regulations, applies as a whole to all motor vehicles (49 CFR 575.4), but the consumer information item requiring reports on brake performance is limited to passenger cars and motorcycles (49 CFR S571.101).#With regard to rollover resistance, the agency has issued an advance notice of proposed rulemaking to collect information on rollover resistance, but no requirement to report on rollover performance exists at this time.#Yours truly,Stephen P. Wood,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.