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 |
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ID: aiam0134OpenHonorable John B. Anderson, House of Representatives, Washington, DC 20515; Honorable John B. Anderson House of Representatives Washington DC 20515; Dear Mr. Anderson: Thank you for your January 8 letter concerning comments by Mr. Jackso Decker of the E. D. Pitnyre Company, which was addressed to the National Highway Safety Bureau on December 20, 1968. I regret that Miss Claybrook of my staff was unable to locate Mr. Decker's letter after the call from your office requesting a copy of my response to Mr. Decker.; Mr. Decker's letter consists of comments to the Federal Highwa Administration Dockets on the pending proposed regulations under which information would be supplied by manufacturers to consumers about various safety performance characteristics of motor vehicles. My staff was unaware of this letter because it was addressed to the Docket and was sent by the mail room directly to the legal office which maintains all dockets. The dockets contain much of the source material which serves as the basis for final rule making on proposed standards and regulations.; In addition, letters such as this are seldom answered not only becaus it is not appropriate to debate the substance of pending rulemaking actions, but also because the purpose of such correspondence is to provide information to the Government in the development of rulemaking. It is not treated as routine correspondence with the agency. In addition, the volume of such comments frequently reaches such vast proportions that it would be virtually impossible to answer them. For example, in response to a recent Federal Highway Administration proposed regulation some 4,000 comments were submitted.; Mr. Decker, incidentally, does not indicate he expected a specifi answer to his letter but, rather, in his last paragraph, asks that his views 'be given serious consideration before proceeding with the issuance of part 275 of the Federal Motor Vehicle Safety Standards.'; On December 30, 1968, the Federal Highway Administrator issued a notic extending for 60 days the time for filing comments on a number of the proposed regulations for consumer information. This notice also specified that the proposed regulations would not apply to vehicles produced in two or more stages. I am enclosing a copy of this notice with the appropriate section marked for your information.; I regret that we had to ask you to supply a copy of Mr. Decker' letter, but I trust that the above information resolves the issues he raised.; Sincerely, William Haddon, Jr., M.D., Director |
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ID: aiam0135OpenHonorable John B. Anderson, House of Representatives, Washington, DC 20515; Honorable John B. Anderson House of Representatives Washington DC 20515; Dear Mr. Anderson: Thank you for your January 8 letter concerning comments by Mr. Jackso Decker of the E. D. Pitnyre Company, which was addressed to the National Highway Safety Bureau on December 20, 1968. I regret that Miss Claybrook of my staff was unable to locate Mr. Decker's letter after the call from your office requesting a copy of my response to Mr. Decker.; Mr. Decker's letter consists of comments to the Federal Highwa Administration Dockets on the pending proposed regulations under which information would be supplied by manufacturers to consumers about various safety performance characteristics of motor vehicles. My staff was unaware of this letter because it was addressed to the Docket and was sent by the mail room directly to the legal office which maintains all dockets. The dockets contain much of the source material which serves as the basis for final rule making on proposed standards and regulations.; In addition, letters such as this are seldom answered not only becaus it is not appropriate to debate the substance of pending rulemaking actions, but also because the purpose of such correspondence is to provide information to the Government in the development of rulemaking. It is not treated as routine correspondence with the agency. In addition, the volume of such comments frequently reaches such vast proportions that it would be virtually impossible to answer them. For example, in response to a recent Federal Highway Administration proposed regulation some 4,000 comments were submitted.; Mr. Decker, incidentally, does not indicate he expected a specifi answer to his letter but, rather, in his last paragraph, asks that his views 'be given serious consideration before proceeding with the issuance of part 275 of the Federal Motor Vehicle Safety Standards.'; On December 30, 1968, the Federal Highway Administrator issued a notic extending for 60 days the time for filing comments on a number of the proposed regulations for consumer information. This notice also specified that the proposed regulations would not apply to vehicles produced in two or more stages. I am enclosing a copy of this notice with the appropriate section marked for your information.; I regret that we had to ask you to supply a copy of Mr. Decker' letter, but I trust that the above information resolves the issues he raised.; Sincerely, William Haddon, Jr., M.D., Director |
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ID: aiam5180OpenMr. Joseph G. Wilson President The Monmouth Corporation Box 143 Highlands, NJ 07732; Mr. Joseph G. Wilson President The Monmouth Corporation Box 143 Highlands NJ 07732; "Dear Mr. Wilson: Thank you for your letter informing us of th Blu-Lite system, which your company developed. You stated that the system 'protects a vehicle driver from the threat of rear-end collision.' You enclosed a brochure for our information, and would like to demonstrate your system to us. We regret that we cannot accept your offer for a demonstration. In addition, as discussed below, we must advise you that Blu-Lite appears to conflict with both Federal and local laws. Your brochure shows that Blu-Lite is a three compartment lamp, consisting of a center compartment with blue lens (described as 'emergency stop') flanked by two 'red stop lights'. Blue-Lite is shown installed in the rear parcel shelf, apparently as a substitute for the center highmounted stop lamp. In use, Blu-Lite flashes rapidly. The center highmounted stop lamp has been required as original equipment on all passenger cars manufactured on and after September 1, 1985. The effect of Section 108(a)(2)(A) of the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1397(a)(2)(A)) is to forbid any manufacturer, distributor, dealer, or motor vehicle repair business from removing the center highmounted stop lamp, and replacing it with any lamp that does not meet the requirements for the center lamp that was original equipment. Blu-Lite does not meet the original equipment specifications in lamp color, which must be red, and in operation, which must be steady-burning. Thus, any manufacturer, distributor, dealer, or motor vehicle repair business who substituted Blu-Lite for an original equipment center highmounted stop lamp would appear to be in violation of Section 108(a)(2)(A). The Safety Act does not prohibit a vehicle owner from installing Blu-Lite, or any other person, including manufacturers, distributors, dealers, and motor vehicle repair businesses, from installing it on a passenger car manufactured before September 1, 1985. However, the legality of its use must be determined under state laws. It is our impression that many states allow the use of blue lamps only on emergency vehicles. Additionally, many states have laws similar to the Federal one as it relates to the performance and use of the center highmounted stop lamp. If you wish to confirm this, we suggest that you consult the American Association of Motor Vehicle Administrators, 4600 Wilson Boulevard, Arlington, Va. 22203. Sincerely, John Womack Acting Chief Counsel "; |
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ID: aiam5165OpenMr. Arvind V. Rajan Vice President, Marketing and Planning Solectria Corporation 27 Jason Street Arlington, MA 02174; Mr. Arvind V. Rajan Vice President Marketing and Planning Solectria Corporation 27 Jason Street Arlington MA 02174; "Dear Mr. Rajan: We have received your letter of March 30, 1993, askin for confirmation that Solectria Corporation is permitted to import nonconforming motor vehicles for conversion to electric power, provided that the vehicles will be exported immediately following conversion. The vehicle you wish to import is the Suzuki Swift, similar to the Suzuki Swift that has been certified by its manufacturer for sale in the United States, except that the steering column is on the right hand side, and that it has not been certified. There is no section of the importation provisions of the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1381 et seq.) that directly permit the importation of nonconforming vehicles for purposes of repair or alteration. Obviously, the failure of such vehicles to comply with the Federal motor vehicle safety standards poses no risk of traffic accidents, or deaths and injuries resulting from such accidents if these vehicles are never driven on the public roads. In these instances, the agency tries to provide an interpretation of the Act that is consistent with both the purpose of the Act and the facts at hand. Section 108(b)(3) of the Act (15 U.S.C. 1397(b)(3)), in effect, allows importation of a nonconforming motor vehicle 'intended solely for export, and so labeled or tagged on the vehicle . . . and on the outside of the container, if any which is exported.' As the legislative history of this section makes clear, ' t his legislation does not purport to establish standards for motor vehicles . . . to be used entirely outside the United States.' (House Report 1776, page 24). Section 108(b)(3) has been implemented by 49 CFR 591.5(c). We believe that, under the facts as described in your letter, it would be appropriate for Solectria to import nonconforming Suzuki Swifts for conversion to electric power pursuant to paragraph 591.5(c). The vehicles have not been imported for use on the American roads, but solely for export following their conversion. We assume that Solectria will label the converted vehicles and their containers, if applicable, in accordance with the regulatory requirement. If we may help you in any other way, please let us know. Sincerely, John Womack Acting Chief Counsel"; |
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ID: aiam1074OpenMr. Stan Haransky, Associate Director, School Bus Manufacturers Institute, 5530 Wisconsin Avenue, Suite 1220, Washington, DC 20015; Mr. Stan Haransky Associate Director School Bus Manufacturers Institute 5530 Wisconsin Avenue Suite 1220 Washington DC 20015; Dear Mr. Haransky: This is in response to the two petitions for rulemaking dated Februar 15, 1973, that you submitted with respect to safety standards applicable to school buses. In one you requested that future standards applicable to school buses become effective on January 1, rather than September 1 as is customary with respect to passenger car standards. Your second petition made a specific request that the effective date of the Bus Window Retention and Release Standard, No. 217, which is set at September 1, 1973, be delayed until January 1,1974. The reason you gave was that the normal model changeover period of the school bus industry is around the first of the year, while September 1 is in the middle of the peak production season.; Your first petition did not mention any specific standards, and i really a general request that the NHTSA take into account the normal model changeover period of the school bus industry in making effective date decisions. This request appears to be reasonable, and we will certainly consider that factor with respect to standards that are as yet unissued.; The situation is different, however, in the case of Standard No. 217 The standard was published on May 10, 1972, more than fifteen months before its effective date. We consider this standard to be a very important one from a safety standpoint. Furthermore, the public concern over the safety of school buses is at an extremely high level. It appears probable that school bus buyers, who have become very safety conscious, have been relying on this effective date in their purchasing decisions.; We have been given no evidence that this standard will requir extensive redesign and retooling, and even if it did, a four-month delay imposed only a few months before the scheduled effective date would hardly be ameliorative. We have no reason to disbelieve your statements concerning the normal changeover period of the industry, but surely at this late date the industry must have taken the imminent effective date of Standard 217 into consideration in its production planning.; In consideration of all these factors, we do not judge it to be in th public interest to grant a delay in the effective date of Standard 217 on the basis of the reason you have provided, namely, the normal production cycle of the industry. If you wish to provide more detailed information concerning technological or economic difficulties that may be caused by the effective date of this standard, we will be willing to consider it.; Sincerely, James E. Wilson, Acting Administrator |
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ID: aiam2296OpenMr. James E. Harris, President, Willamette Wheel Inc., 1235 S.E. Grand, Portland, OR 97214; Mr. James E. Harris President Willamette Wheel Inc. 1235 S.E. Grand Portland OR 97214; Dear Mr. Harris: I am writing in response to your April 21, 1976, telephone conversatio with Mark Schwimmer of this office, concerning the modification work that you perform on previously certified Datsun pickup trucks, which consists of converting them from two-wheel- to four-wheel-drive vehicles.; As indicated in the October 30, 1975, letter from Richard B. Dyson t you, you are a vehicle alterer who is subject to the requirements of 49 CFR 567.7. That section requires that you affix a label to the vehicle stating that, *as altered*, the vehicle conforms to applicable Federal motor vehicle safety standards.; The Federal government does not certify or otherwise issue advanc approval of motor vehicles. As Mr. Schwimmer explained, the statement on the label constitutes your certification of conformity. If you fail to provide this certification, or if in the exercise of due care you have reason to know that it is false or misleading, you are subject to civil penalties under the National Traffic and Motor Vehicle Safety Act of 1966, as amended.; All altered vehicles must comply fully with all applicable safet standards. Therefore, as Mr. Schwimmer further explained, you would not be relieved of the requirements of S567.7 simply by virtue of the fact that, as altered, the vehicle complied fully with the standards. You would be relieved of the requirements only if both of the following conditions were met:; >>>(i) the alteration is performed solely by the addition substitution, or removal of readily attachable components such as tire and rim assemblies, or by minor finishing operations such as painting, and; (ii) the stated weight ratings of the vehicle are still valid.<<< Because the conversion of the vehicles in question does not meet th first condition, you are subject to the requirements of S 567.7. Please note further that, if your modifications affect the validity of the weight ratings assigned to the vehicles by Datsun, your label must show valid, modified ratings.; An information sheet entitled 'Where to Obtain Federal Motor Vehicl Safety Standards and Regulations' is enclosed for your convenience.; Yours truly, Stephen P. Wood, Assistant Chief Counsel |
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ID: aiam1156OpenMr. Erik Sundelin, Trelleborg Gummifabriks Aktiebolag Fack, S-231 01 TRELLEBORG/Sweden; Mr. Erik Sundelin Trelleborg Gummifabriks Aktiebolag Fack S-231 01 TRELLEBORG/Sweden; Dear Mr. Sundelin: #This is in reply to your letter of May 28, 1973 asking whether you may, consistently with Federal Motor Vehicle Safety Standard No. 109, label maximum load and maximum permissible inflation pressure as follows, using the 165 SR 15 tire size designation as an example: #>>>1. Max Load 1200 Lbs. At 36 psi #2. Max Load 1200 Lbs. At Max Press 36 psi<<< #We do not believe alternative 1 to be consistent with Standard No. 109 because it is not clear that 36 psi is the maximum permissible inflation pressure. Alternative 2 does so indicate, however, and we believe that alternative to be consistent with the standard. #Yours truly, Richard B. Dyson, Assistant Chief Counsel; |
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ID: aiam5263OpenMr. Dennis G. Moore President Sierra Products Inc. 1113 Greenville Road Livermore, CA 94550; Mr. Dennis G. Moore President Sierra Products Inc. 1113 Greenville Road Livermore CA 94550; "Dear Mr. Moore: We have received your letter of September 29, 1993 with reference to the location requirements of Standard No. 108 for identification (i.d.) lamps. Table II of the standard in pertinent part specifies the following location for i.d. lamps: 'On the rear - 3 lamps as close as practicable to the top of the vehicle at the same height, as close as practicable to the vertical centerline . . . .' You reference at least two instances in the past 20 years or longer in which 'NHTSA has allowed the slight misalignment of I.D. lights because of `Practical' circumstances,' and have asked for copies of these interpretations. We are unaware of these interpretations. In their absence, you have asked for an interpretation of the phrase 'at the same height' that would permit the mounting height of the center lamp to deviate slightly from the height of the two lamps that flank it, as shown in your letter. You depict two other possible configurations in which the three lamps are mounted at identical heights. In one configuration, the lower edges of the outboard lamps hang below the frame 'making them vulnerable to being damaged or knocked off' in your opinion. In the second configuration, the lamps are raised and protected, but the center lamp is somewhat obscured by the 'typical roller or protective pad.' You deem these configurations undesirable for safety reasons. The question to be answered is whether the configuration you prefer is 'as close as practicable to the top of the vehicle at the same height' (note the absence of a comma between 'vehicle' and 'at'). The determination of practicability is initially that of the manufacturer. Unless it is clearly erroneous, NHTSA will not question it. In the absence of a superstructure, the frame location may be regarded as being 'as close as practicable to the top of the vehicle. . . .' Because 'at the same height' is part of the same phrase, practicability also governs placement of the lamps at the same height. A manufacturer may determine that, for the sake of practicability, i.d. lamps may be mounted at a height sufficient to protect them from breakage (the outboard lamps) and to ensure compliance with photometric requirements (the center lamp). The configuration you depict is sufficiently close to the literal reading of the phrase 'at the same height' that NHTSA would not question the manufacturer's determination of practicability with respect to the mounting height of the center i.d. lamp. Sincerely, John Womack Acting Chief Counsel "; |
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ID: aiam0358OpenMr. Armand F. Macmanus, Phillips Petroleum Company, Bartlesville, Oklahoma 74003; Mr. Armand F. Macmanus Phillips Petroleum Company Bartlesville Oklahoma 74003; Dear Mr. Macmanus: This is in reply to your letter of May 11, 1971, in which you reques an opinion on whether certain tires manufactured by Phillips Petroleum Company are subject to the requirements governing tires that have been issued pursuant to the National Traffic and Motor Vehicle Safety Act (15 U.S.C. S1391 *et seq*). You state that the tires in question result from Phillips' efforts to develop improved tread rubber, and are manufactured by purchasing new tires, buffering them down, and then retreading the remaining casings with experimental tread rubber compounds. You state further that after the casings have been retreaded, the tread rubber compounds are evaluated by stationary wheel testing, road testing, or both, and indicate that some of the road testing takes place on the public highways.; We agree with your conclusion that these tires are not retreade pneumatic tires under Motor Vehicle Safety Standard No. 117, because they are not manufactured from used tires. However, in our view these tires are new pneumatic tires, and accordingly are subject to the requirements of Motor Vehicle Safety Standard No. 109.; Section 108(a)(1) of the National Traffic and Motor Vehicle Safety Ac (15 U.S.C. S1397(a)(1)) provides that no person shall; >>>'manufacture for sale, sell, offer for sale, or introduce or delive for introduction in interstate commerce any motor vehicle or item of motor vehicle equipment manufactured on or after the date any applicable Federal motor vehicle safety standard take effect... unless it is in conformity with such standard.'<<<; Phillips' use of the public roads for testing these tires is a introduction of them in interstate commerce and is prohibited by section 108(a)(1) if the tires do not conform to Standard No. 109.; One objective of the Act that you did not mention in your letter is th prevention of possibly hazardous motor vehicles or motor vehicle equipment from being used on the public highways, where they may endanger not only the driver of the vehicle in question, but other users of the highway as well. The tires need not be manufactured for sale to the general public in order for a violationoof(sic) section 108(a)(1) to occur.; However, if the testing of these tires is confined to the laboratory o to private roads, the prohibition of the Act will not apply to them.; I trust this answers your question.If you have further questions Please write.; Sincerely,Lawrence R. Schneider, Acting Chief Counsel |
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ID: aiam1740OpenMr. J. L. Brown, President, Brown Truck and Trailer Mfg. Co., P.O. Box 1281, Charlotte, NC 28201; Mr. J. L. Brown President Brown Truck and Trailer Mfg. Co. P.O. Box 1281 Charlotte NC 28201; Dear Mr. Brown: This responds to your December 11, 1974, question whether Standard No 121, *Air brake systems*, or any other Federal brake regulation applies to trailers that are equipped with electric brakes. In a January 2, 1975, telephone conversation with Mr. Herlihy of this office, you indicated that the brake system on your products is entirely electrical.; No Federal braking standards apply to your electrically-brake trailers. Standard No. 121 applies only to trucks, buses, and trailers that the manufacturer chooses to equip with an air brake system.; Yours truly, Richard B. Dyson, Acting 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.