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: aiam3239OpenMr. David T. Steadman, Senior Section Engineer, Project and Development Center, British Standards Institution, Maylands Avenue, Memel Hempstead, Herts HP2 4SQ England; Mr. David T. Steadman Senior Section Engineer Project and Development Center British Standards Institution Maylands Avenue Memel Hempstead Herts HP2 4SQ England; Dear Mr. Steadman: Please accept my apologies for our delay in responding to your lette of November 30, 1979. You asked whether five enumerated types of machinery capable of highway travel would be considered motor vehicles to which Federal Motor Vehicle Safety Standards and fuel economy standards would apply. The vehicles enumerated in your letter were:; >>>Wheel-mounted front-end loader, Crawler-mounted front-end loader Crawler- mounted hydraulic excavator, (Rough terrain) fork lift truck, Backhoe-loader<<<; As explained below, these vehicles are not subject to fuel econom standards. However, without more detailed information concerning these machines, we cannot give you a definitive answer as to their possible classification as motor vehicles to which Federal motor vehicle safety standards may be applicable. Nonetheless, we can provide you with guidelines for use in determining the status of these vehicles.; Pursuant to Title V of the Motor Vehicle Information and Cost Saving Act (15 U.S.C. 2001), this agency has promulgated regulations which establish the categories of motor vehicles that are subject to fuel economy standards. The regulations (49 CFR Part 523, copy enclosed) state that fuel economy standards are applicable only to automobiles, light trucks, and automobiles capable of off-highway travel. The definitions of these items which appear in Part 523 do not appear to encompass the types of vehicles that you enumerated in your letter.; Our safety standards apply to a vehicle and its manufacturer only i the vehicle qualifies as a 'motor vehicle' under the provisions of the National Traffic and Motor Vehicle Safety Act of 1966. Section 102(3) of the Act (15 U.S.C. 1391(3)) defines 'motor vehicle' as:; >>>any vehicle driven or drawn by mechanical power manufacture primarily for use on the public streets, roads, and highways, except any vehicle operated exclusively on a rail or rails.<<<; Thus, a motor vehicle is a vehicle which the manufacturer has reason t expect will use public highways at least part of the time.; Tracked (i.e., crawler mounted) and other vehicles incapable of highwa travel are not motor vehicles. In addition, vehicles intended and sold solely for off-road use (e.g., aircraft runway vehicles and underground mining vehicles) are not considered vehicles even if operationally capable of highway travel. They would, however, be considered motor vehicles if the manufacturer knew that a substantial proportion of his customers actually would use them on the highway.; There are some vehicles which are excepted from the motor vehicl classification despite their use of the highway. Highway maintenance and construction equipment lane strippers, self-propelled asphalt pavers, and other vehicles whose maximum speed does not exceed 20 miles per hour and whose abnormal configuration distinguishes them from the traffic flow are not considered motor vehicles.; Historically, the agency has regarded vehicles which use the highway o a necessary and recurring basis to move between work sites as motor vehicles. The primary function of such vehicles is of a mobile, workperforming nature and as such their manufacturer contemplates a primary use of the highway. Mobile cranes, rigs, and towed equipment such as chippers and pull-type street sweepers are examples of vehicles which, in the agency's views, qualify as trucks or trailers and, as such are subject to several of the Motor Vehicle Safety Standards.; However, in a recent decision the United States Court of Appeals fo the Seventh Circuit held that mobile construction equipment does not fall within the definition of 'motor vehicles' found in section 102(3) of the Act. *Koehring Co.* v. *Adams*, 605 F.2d 280 (7th Cir. 1979). The agency has decided not to seek certiorari to the United States Supreme Court. Accordingly, the agency considers itself to be bound by the court's judgment in *Koehring* within the territorial limits of the Seventh Circuit (i.e. the states of Illinois, Indiana and Wisconsin) although it has not yet formulated its policy with respect to the nationwide applicability of the court's holdings. A manufacturer seeking to export vehicles from the United Kingdom to any of these states might wish to consult an attorney who practices in the Seventh Circuit.; A copy of the *Koehring* decision is enclosed. Also enclosed is a information sheet containing advice for obtaining an up-to-date copy of the regulations which apply to motor vehicles and their manufacturers, and a copy of 49 CFR Part 523, *Vehicle Classification*.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam0874OpenMr. E.T. Brodie, Bandag, Incorporated, 1056 Hershey Road, Muscatine, Iowa 52761; Mr. E.T. Brodie Bandag Incorporated 1056 Hershey Road Muscatine Iowa 52761; Dear Mr. Brodie: In your letter of September 27 you suggest that Standard 117 paragraph 5.2.1(b) which relates to exposing fabric during the buffing operation of the retread process might be interpreted as forbidding the retreading of casings containing nail holes. You further quote the conclusion of an outside contractor of a Department of Transportation sponsored tire repair study that 'while test wheel tests could be passed on repaired tires, road test showed them all to be satisfactory.'; We do not consider nail holes to constitute and exposure of cord fabri within the meaning of the standard. Briefly, our examination of retread tires to date shows that nail holes which have been repaired with the repair materials vulcanized to the inside of the tire are very satisfactory. We have cut through such repairs and find them to be sound even after being subjected to Federal Motor Vehicle Safety Standards No. 109 and No. 117, Endurance and High Speed Wheel Tests. Provided the nail holes are permanently sealed on the inside of the tire they appear to be no more objectionable than the casing penetrations made by new tire manufacturers and retreaders in their awl venting procedures.; The Discussion Paper presented at the National Highway Traffic Safet Administration Technical Meeting held on April 10, 1969, contained rather detailed requirements for casings that were to be retreaded. Included within this extensive list were requirements for not retreading a casing if 'two closed punctures (nail hole type) which extend through the fabric, or are less then 15 inches apart or are outside if the tread area.' As a result of the comments received at the April 10, 1969, technical conference, at which you and Mr. Vischer attended, the Administration changed the casing condition requirements to only prohibit retreading of casing which had cord or bead wire exposed. The Administration considers the casing as part of the raw material used in the retreading process and as such, each retreader must use his expertise in casing selection prior to applying his DOT self-certification symbol.; Supplementing the above, we have noted that repairs with the repai materials not bonded to the carcass loosen during flexing and have a high incidence of failure on the Endurance and High Speed Wheel Tests.; Sincerely, E.T. Driver, Director, Office of Operating Systems, Moto Vehicle Programs; |
|
ID: aiam1094OpenMr. Lowell Liebenstein, President, Gil-Mar Welding Corp., 2142 Maple Road, Grafton, WI 53024; Mr. Lowell Liebenstein President Gil-Mar Welding Corp. 2142 Maple Road Grafton WI 53024; Dear Mr. Liebenstein: This is in reply to your letter of March 14, 1973, asking how to compl with NHTSA Certification regulations in cases where you supply a trailer chassis or frame only, and another manufacturer installs the body. In another example, you supply the vehicle without an axle assembly, which is, we assume, also installed by another party.; Based on your letter, the procedures to be foloowed in certifyin vehicles such as these are those contained in NHTSA regulations for 'Vehicles Manufactured in Two or More Stages' (49 CFR Part 568, copy enclosed). Briefly, these regulations require the incomplete vehicle manufacturer, who would be you in these cases, to furnish with the incomplete vehicle a document indicating the extent that the incomplete vehicle a document indicating the extent that the incomplete vehicle conforms to Federal standards, and what the final stage manufacturer must do in order that the completed vehicle will conform to all applicable standards.; If upon your review of these regualtions you have further questions, w will be pleased to respond to them.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam1091OpenMr. Lowell Liebenstein, President, Gil-Mar Welding Corp., 2142 Maple Road, Grafton, WI 53024; Mr. Lowell Liebenstein President Gil-Mar Welding Corp. 2142 Maple Road Grafton WI 53024; Dear Mr. Liebenstein: This is in reply to your letter of March 14, 1973, asking how to compl with NHTSA Certification regulations in cases where you supply a trailer chassis or frame only, and another manufacturer installs the body. In another example, you supply the vehicle without an axle assembly, which is, we assume, also installed by another party.; Based on your letter, the procedures to be followed in certifyin vehicles such as these are those contained in NHTSA regulations for 'Vehicles Manufactured in Two or More Stages' (49 CFR Part 568, copy enclosed). Briefly, these regulations require the incomplete vehicle manufacturer, who would be you in these cases, to furnish with the incomplete vehicle a document indicating the extent that the incomplete vehicle a document indicating the extent that the incomplete vehicle conforms to Federal standards, and what the final stage manufacturer must do in order that the completed vehicle will conform to all applicable standards.; If upon your review of these regulations you have further questions, w will be pleased to respond to them.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam1088OpenMr. Lowell Liebenstein, President, Gil-Mar Welding Corp., 2142 Maple Road, Grafton, WI 53024; Mr. Lowell Liebenstein President Gil-Mar Welding Corp. 2142 Maple Road Grafton WI 53024; Dear Mr. Liebenstein: This is in reply to your letter of March 14, 1973, asking how to compl with NHTSA Certification regulations in cases where you supply a trailer chassis or frame only, and another manufacturer installs the body. In another example, you supply the vehicle without an axle assembly, which is, we assume, also installed by another party.; Based on your letter, the procedures to be followed in certifyin vehicles such as these are those contained in NHTSA regulations for 'Vehicles Manufactured in Two or More Stages' (49 CFR Part 568, copy enclosed). Briefly, these regulations require the incomplete vehicle manufacturer, who would be you in these cases, to furnish with the incomplete vehicle a document indicating the extent that the incomplete vehicle a document indicating the extent that the incomplete vehicle conforms to Federal standards, and what the final stage manufacturer must do in order that the completed vehicle will conform to all applicable standards.; If upon your review of these regulations you have further questions, w will be pleased to respond to them.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam1618OpenMr. K. Nakajima, Director/General Manager, Toyota Motors Sales, U.S.A., Inc., Lyndhurst Office Park, 1099 Wall Street, West, Lyndhurst, NJ 07071; Mr. K. Nakajima Director/General Manager Toyota Motors Sales U.S.A. Inc. Lyndhurst Office Park 1099 Wall Street West Lyndhurst NJ 07071; Dear Mr. Nakajima:#This is in response to your letter of September 9 1974, requesting an interpretation of Federal Motor Vehicle Safety Standard No. 101, specifically, whether Toyota should identify controls with words as well as symbols.#Your use of symbols alone, without the words specified in Column 2 of Table 1 to identify the headlamp, hazard warning, and washer/wiper controls on the 1974 Corona model, is not in compliance with the standard. Symbols are merely an option which may be used in addition to the mandatory word identification.#I have forwarded a copy of your letter to the NHTSA Office of Standard Enforcement, for such action as it deems necessary.#Your truly, Richard B. Dyson, Acting Chief Counsel; |
|
ID: aiam1219OpenMr. D. Black, Technical Director, Alfa Romeo, Inc., 250 Sylvan Avenue, Englewood Cliffs, NJ 07632; Mr. D. Black Technical Director Alfa Romeo Inc. 250 Sylvan Avenue Englewood Cliffs NJ 07632; Dear Mr. Black: This is in response to your letter of August 9, 1973, in which yo inquire whether Alfa Romeo may add to the consumer information 'handouts' for prospective purchasers, required by NHTSA regulations, the consumer information required by the Environmental Protection Agency.; As long as the information required by NHTSA is presented in conformit with 49 CFR Part 575, we have no objection to the inclusion within the same covers of additional information relative to EPA requirements.; The wall posters you mentioned are not required by our regulations, s you may do with them as you please.; Sincerely, Lawrence R. Schneider, Chief Counsel |
|
ID: aiam1218OpenMr. D. Black, Technical Director, Alfa Romeo, Inc., 250 Sylvan Avenue, Englewood Cliffs, NJ 07632; Mr. D. Black Technical Director Alfa Romeo Inc. 250 Sylvan Avenue Englewood Cliffs NJ 07632; Dear Mr. Black: This is in response to your letter of August 9, 1973, in which yo inquire whether Alfa Romeo may add to the consumer information 'handouts' for prospective purchasers, required by NHTSA regulations, the consumer information required by the Environmental Protection Agency.; As long as the information required by NHTSA is presented in conformit with 49 CFR Part 575, we have no objection to the inclusion within the same covers of additional information relative to EPA requirements.; The wall posters you mentioned are not required by our regulations, s you may do with them as you please.; Sincerely, Lawrence R. Schneider, Chief Counsel |
|
ID: aiam2197OpenMr. Danny Lanzdorf, Supervising Engineer, Oshkosh Truck Corporation, P.O. Box 2566, Oshkosh, WI 54901; Mr. Danny Lanzdorf Supervising Engineer Oshkosh Truck Corporation P.O. Box 2566 Oshkosh WI 54901; Dear Mr. Lanzdorf: This responds to Oshkosh Truck Company's January 22, 1976, questio whether a vehicle complies with S5.1.1 of Standard No. 121, *Air Brake System*, when it is moving must also comply with the requirement when it is stationary. Section S5.1.1 specifies an air compressor of sufficient capacity to increase air pressure in the supply and service reservoirs from 85 p.s.i. to 100 p.s.i. within a limited period when the engine is operating at the vehicle manufacturer's maximum recommended rpm.; Section S5.1.1 does not specify whether or not the vehicle is moving a a test condition for the requirement. In view of the absence of this test condition, the NHTSA will resolve differences in this test condition in the manufacturer's favor if they affect the outcome of testing.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam5141OpenMr. Thomas L. Wright Coordinator, Technical Support Unit State of New Jersey Department of Law and Public Safety Division of Motor Vehicles Trenton, NJ 08666; Mr. Thomas L. Wright Coordinator Technical Support Unit State of New Jersey Department of Law and Public Safety Division of Motor Vehicles Trenton NJ 08666; "Dear Mr. Wright: This responds to your letter to Patrick Boyd of th National Highway Traffic Safety Administration's (NHTSA's) Office of Vehicle Safety Standards, concerning window tinting. Your letter has been referred to my office for reply. Your questions relate to a January 22, 1992 (57 FR 2496) notice of proposed rulemaking (NPRM) on the tinting requirements of Safety Standard No. 205, 'Glazing Materials.' You ask about the status of the NPRM. The agency received a large number of comments on this rulemaking. We have reviewed the comments and are analyzing the issues raised in this rulemaking. You also ask about a statement in the NPRM about Federal preemption of state window tinting laws. You ask whether Federal law preempts a state law that permits add-on window tinting material for medical or aesthetic reasons. As explained below, the answer is no, provided that the state law regulates conduct other than that regulated by Federal law. Your question was addressed in the NPRM's discussion of the Federalism implications of the proposed rule (p. 2507). By way of background, NHTSA issued Standard 205 under the authority of the National Traffic and Motor Vehicle Safety Act. The standard currently imposes a minimum level of light transmittance of 70% in all areas requisite for driving visibility (which includes all windows on passenger cars). The primary purpose of this requirement is to ensure adequate visibility through the windows, thereby reducing the risk of a motor vehicle crash. Section 103(d) of the Safety Act provides that: Whenever a Federal motor vehicle safety standard ... is in effect, no State or political subdivision of a State shall have any authority either to establish, or to continue in effect, with respect to any motor vehicle or item of motor vehicle equipment any safety standard applicable to the same aspect of performance of such vehicle or item of equipment which is not identical to the Federal standard. Whether state law is preempted under 103(d) depends in part on the conduct that is regulated by that law. Federal safety standards regulate the manufacture and sale of new motor vehicles and new items of motor vehicle equipment. State law would be preempted to the extent it established performance requirements applicable to the manufacture of vehicles or glazing that differ from those in Standard 205. State law would also be preempted if it purported to allow the manufacture or sale of glazing materials or new vehicles containing glazing material that did not meet the specifications of Standard 205. Federal law also regulates modifications made to new and used vehicles by motor vehicle manufacturers, distributors, dealers and repair businesses. Section 108(a)(2)(A) of the Safety Act provides that: No manufacturer, distributor, dealer, or motor vehicle repair business shall knowingly render inoperative, in whole or in part, any device or element of design installed on or in a motor vehicle ... in compliance with an applicable Federal motor vehicle safety standard. The effect of this is to impose limits on the tinting practices of businesses listed in 108(a)(2)(A). These businesses may not install tinting on new or used vehicles that reduces the light transmittance of windows covered by Standard 205 to a level below the Federal requirement of 70 percent. A state law would be preempted if it purported to allow modifications violating Standard 205 by these named businesses. Section 108(a)(2)(A) does not apply to actions by individual vehicle owners. Because Federal safety standards regulate the manufacture and sale of new motor vehicles, state requirements applicable to the registration and inspection of motor vehicles after the first sale to a consumer are not preempted merely because they are not identical to the Federal safety standards, as long as they do not interfere with the achievement of the purposes of Federal law. Therefore, a state could permit the registration of a vehicle which had been altered by its owner by the addition of window tinting, even when the tinting reduces the light transmittance below the Federal standard. However, the state cannot legitimize conduct - the rendering inoperative of glazing by commercial businesses installing window tinting - that is illegal under Federal law. I have enclosed a copy of the Report to Congress on Tinting of Motor Vehicle Windows which you requested. I hope you find this information helpful. If you have any other questions, please contact Marvin Shaw of my staff at this address or by phone at (202) 366-2992. Sincerely, John Womack Acting Chief Counsel Enclosure"; |
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.