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
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ID: aiam4515OpenMs. C. Dianne Black Engineering Manager Jaguar Cars, Inc. 600 Willow Tree Road Leonia, NJ 07605; Ms. C. Dianne Black Engineering Manager Jaguar Cars Inc. 600 Willow Tree Road Leonia NJ 07605; Dear Ms. Black: Thank you for your letter of April l4, l988, providin further information about the Jaguar headlamp levelling system discussed in your letters of June and October l987 to which I responded on February 1, 1988. We support your efforts to call the driver's attention to the fact that the system does not automatically return to the 'zero' position from either of the two adjustment positions when those loading conditions no longer exist. Sincerely, Erika Z. Jones Chief Counsel; |
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ID: aiam1347OpenMr. Peter J. Sferrazza, Staff Counsel, 811 North First Avenue, Wausau, WI 54401; Mr. Peter J. Sferrazza Staff Counsel 811 North First Avenue Wausau WI 54401; Dear Mr. Sferrazza: In response to your request of November 28, 1973, I have enclosed copy of Part 580, *Odometer Disclosure Requirements*, 49 CFR Part 580, which was issued under the authority of the Motor Vehicle Information and Cost Savings Act of 1972, 15 U.S.C. S 1988.; The transferor must disclose the mileage as it is recorded on th odometer, and in addition that he knows that reading to be inaccurate if such is the case. This means that a transferor would check the box indicating that the reading does not reflect the mileage, if he knew that the vehicle had traveled more than 100,000 miles. The buyer would then be on notice to ask why the reading was not accurate and to be told that the vehicle had more than 100,000 miles on it.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam2992OpenMr. Hisakazu Murakami, Nissan Motor Co., Ltd., P.O. Box 1606, 560 Sylvan Avenue, Englewood Cliffs, NJ 07632; Mr. Hisakazu Murakami Nissan Motor Co. Ltd. P.O. Box 1606 560 Sylvan Avenue Englewood Cliffs NJ 07632; Dear Mr. Murakami: This responds to your letter of January 23, 1979, concerning a ne design belt system for rear seat lap belts that you would like to use in future vehicles. You ask if the proposed design would comply with the requirements of Safety Standard No. 208.; The answer to your question depends in which seating position in th rear seat of the vehicle the proposed belt system would be used. The new design would not comply with paragraph S7.1.1 of Safety Standard No. 208 if installed at outboard designated seating positions in the rear seat. That paragraph requires lap belts to adjust by means of an emergency- locking or automatic-locking retractor to fit persons whose dimensions range from those of a 50th-percentile 6-year-old child to those of a 95th percentile adult male. In some cases your proposed design would not adjust automatically to fit a 95th- percentile adult male.; The proposed design would comply with the standard, however, i installed in the center seating position of the rear seat, since paragraph S7.1.1.2 specifies that a seat belt assembly installed at any designated seating position other than the outboard positions of the front and second seats shall adjust either by a retractor or by a manual adjusting device.; Since your new belt system design would currently be precluded fo outboard designated seating positions, you may wish to petition for amendment of Safety Standard No. 208. Any petition should include an adequate description of the belt design, including: (1) seating positions for which the belt system would be applicable, (2) advantages of the system, (3) size of the belt system hardware, and (4) problems, if any, associated with automatic retraction of the belt system.; The National Highway Traffic Safety Administration hereby grants you request for confidentiality of the new belt system design described in your letter. Please notify us if the design becomes public in the future. Also, please note that if you petition for rulemaking in this area, the details of your belt design would probably have to be disclosed to the public, at least in general terms.; Sincerely, Frank Berndt, Acting Chief Counsel |
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ID: aiam4145OpenMs. Brenda Hartman, 8617 Creston, Pinckney, MI 48169; Ms. Brenda Hartman 8617 Creston Pinckney MI 48169; Dear Ms. Hartman: Thank you for your letter of February 27, 1986, asking how ou regulations affect a product you are considering. In your letter, you asked the agency not to disclose your idea for this product. In a phone conversation of April 28, 1986, with Stephen Oesch of my staff, you waived your request for complete nondisclosure and agreed to the disclosure of a generic description of your product. As you requested, we will not disclose the specific details of your product or the sketches you enclosed with your letter.; Your product is designed to reduce the possibility that a young chil could unbuckle a vehicle safety belt. The product would enclose the buckle of the safety belt, so that it is difficult for a child to operate the buckle release.; We have significant reservations about your product. I hope th following discussion explains our reservations and the effect of our regulations on your product.; Our agency has the authority to issue safety standards applicable t new motor vehicles and certain items of motor vehicle equipment. NHTSA, however, does not approve motor vehicles or motor vehicle equipment, nor do we endorse any commercial products. Instead the National Traffic and Motor Vehicle Safety Act establishes a 'self-certification' process under which each manufacturer is responsible for certifying that its products meet our safety standards. The agency periodically tests vehicles and equipment items for compliance with the standards, and also investigates other alleged safety-related defects.; Although we do not have any standards that directly apply to you product, we do have several statutory provisions that could affect it. Manufacturers of motor vehicle equipment such as your product are subject to the requirements in sections 151-159 of the Vehicle Safety Act concerning the recall and remedy of products with defects related to motor vehicle safety. The agency does not determine the existence of safety defects except in the context of a defect proceeding, and thus is unable to say whether your product might or might not contain such a defect. However, the agency has reservations about your product because of our concern that people be able to easily and quickly operate a safety belt in an emergency. As the agency said last year on the related topic of the force level necessary to operate buckles in child restraints:; >>>The agency's safety concerns over child restraint buckle forc release and size stem from the need for convenient buckling and unbuckling of a child and, in emergencies, to quickly remove the child from the restraint. This latter situation can occur in instances of post-crash fires, immersions, etc. A restraint that is difficult to disengage, due to the need for excessive buckle pressure or difficulty in operating the release mechanism because of a very small release button, can unnecessarily endanger the child in the restraint and the adult attempting to release the child. (50 FR 33722, August 21, 1985).<<<; In addition, use of your product can be affected by sectio 108(a)(2)(A) of the Vehicle Safety Act. That section prohibits commercial businesses from knowingly tampering with devices or elements of design installed in a vehicle in compliance with the Federal motor vehicle safety standards. One requirement of Standard No. 209, *Seat Belt Assemblies*, is that the pushbutton release for a safety belt must have a a (sic) minimum area for applying the release force. Installation of your device by a commercial business could be prohibited since it apparently would substantially reduce the minimum area available for applying the release force to the safety belt pushbutton. In addition, Standard No. 302, *Flammability of Interior Materials*, requires new safety belts to meet a flammability resistance requirement. Thus, although Standard No. 302 does not directly apply to aftermarket equipment, commercial businesses could not install your device if it would mean that the safety belt no longer meet (sic) the flammability resistance requirements of Standard No. 302.; The prohibition of section 108(a)(2(A) (sic) does not apply t individual vehicle owners who may install or remove any items of motor vehicle equipment regardless of its effect on compliance with Federal motor vehicle safety standards. However, our policy is to encourage vehicle owners not to remove or otherwise tamper with vehicle safety equipment. Installation of your product by any person could be inconsistent with that policy.; If you have any further questions, please let me know. Sincerely, Erika Z. Jones, Chief Counsel |
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ID: aiam3680OpenW.E.J. Moss, P. Eng., Flyer Industries Limited, 64 Hoka Street, Box 245 Transcona P.O., Winnipeg, Manitoba, Canada R2C 3T4; W.E.J. Moss P. Eng. Flyer Industries Limited 64 Hoka Street Box 245 Transcona P.O. Winnipeg Manitoba Canada R2C 3T4; Dear Mr. Moss: This responds to your January 27, 1983, letter asking about th application of Standard No. 217, *Bus Window Retention and Release*, to the front entrance doors of buses. You ask that the window retention test not be applied to your bus, because application of the required amount of force will cause the door to open. You state further that if the door had no glazing, it would not be tested for retention and, therefore, would be acceptable under the standard.; Standard No. 217 states that all glazing that exceeds 8 inches i diameter shall be tested for retention. During that test, neither the glazing nor the surrounding frame shall open in a manner that would allow a 4-inch sphere to pass through the opening. The intent of this requirements is of course to prevent the ejection of occupants in accidents.; The agency does test the front door of buses for compliance with thi section if they contain glazing that meets the size requirement. In tests that have been conducted, most front doors have complied. Accordingly, the proper construction of front doors in compliance with the requirement would not appear to be a problem. The agency does not believe that it would be in the interest of safety to exempt front door glazing from the test requirements. Although passengers are required to stand behind the standee line as you note in your letter, they may easily be thrown forward of that line in an accident. The agency considers it important to reduce the possibility of their being thrown from the vehicle if such a situation were to arise.; You are technically correct that an all metal door would not be teste for compliance with this retention provision since it would not contain glazing. However, the agency would not view favorably the installation of doors in buses that open so easily in an accident. Use of such doors might be considered to be a safety-related defect subject to the agency's recall and remedy authority.; Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam3395OpenW.M. Bradley, Jr., Auto Damage Claim Examiner, Kemper Group, Mid-Atlantic Division, 1610 Forest Avenue, Richmond, VA 23288; W.M. Bradley Jr. Auto Damage Claim Examiner Kemper Group Mid-Atlantic Division 1610 Forest Avenue Richmond VA 23288; Dear Mr. Bradley: This is in response to your letter of February 10, 1978, requesting listing of those states whose certificates of title have been approved by the agency for use in lieu of the separate Federal odometer form.; The Odometer Disclosure Requirements (49 CFR Part 580) provide that th transferor of a vehicle may make the disclosure required by the Federal odmeter (sic) laws on the state certificate of title, if the state title document contains essentially the same information required on the Federal odometer disclosure statement. If the information contained on the state certificate of title varies from that required by the Federal from (sic), the state must obtain the approval of this agency before its certificate of title can be used as a sustitute for the Federal form.; In order to spare states the burden of an approval process the agenc has indicated that certain variation from the Federal form are acceptable. In the *Federal Register* notice of August 1, 1977, which amended the disclosure regulation, we gave examples of shortened forms that would be acceptable. A state title can be considered to be approved for use as a full disclosure statement if it varies from the Federal form in only those aspects noted in the August 1, 1977, notice, a copy of which is enclosed.; The following states have odometer statements on their motor vehicl titles that are consistent with the requirements of the federal law:; >>>Maryland, Ohio, Massachusetts, Pennsylvania, Michigan, Hawaii Minnesota, New York, North Dakota<<<; In addition, the following states submitted title forms to the agenc asking for approval but had unacceptable statements. Each was advised that before its form could be approved certain additional information was required on its certificate of title. We do not know whether that information has been included on the titles.; >>>North Carolina, Virginia, Delaware, Washington, South Dakota, Utah South Carolina, Wisconsin, Indiana<<<; If you have any further questions, please do not hesitate to write. Sincerely, David W. Allen, assistant Chief Counsel |
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ID: aiam4450OpenMr. Donald N. Stahl District Attorney Office of District Attorney Bureau of Investigation Court House P.O. Box 442 Modesto, CA 95353; Mr. Donald N. Stahl District Attorney Office of District Attorney Bureau of Investigation Court House P.O. Box 442 Modesto CA 95353; "Dear Mr. Stahl: Re: McCoy Tire Service Center D.A. No. CF696 Thi responds to your letter asking about requirements concerning the importation of tire casings. According to your letter, a routine inspection by the California Highway Patrol (CHP) of a local school district's buses disclosed recapped tires on a bus which did not have DOT markings on the tires. The CHP learned that the tire casings were originally designed for use by a rubber tire train in Japan and were new tires that had been imported for recapping purposes. The tire casings were imported as slicks (no tread design), and the slick was removed. The tires were then recapped using the 'bondag' process and sold to the school district. You asked whether it is permissible to import this type of tire casing and, if so, whether the particular type of tire casing meets Department of Transportation standards. Your questions are responded to below. Our opinions are based on the facts provided in your letter. Before addressing your specific questions, I will provide background information about requirements for tires. All tires which are subject to a Federal motor vehicle safety standard must have the symbol 'DOT' molded into the sidewall by the manufacturer or retreader, if those tires are to be imported into the United States. This symbol represents a certification by the manufacturer or retreader that the tire complies with all requirements of the applicable safety standards. New tires for use on school buses are subject to Federal Motor Vehicle Safety Standard No. ll9 (49 CFR 571.119). Section S6.5(a) of the standard requires that all new tires for use on motor vehicles other than passenger cars have the DOT symbol molded into the sidewall by the manufacturer. Tires without this symbol may not be legally imported. This is also true for used tires manufactured on or after the effective date of Standard No. ll9, March l, l975, with one narrow exception. Used tires for use on motor vehicles other than passenger cars which have less than 2/32 inch of tread remaining and which are imported solely for the purpose of being retreaded in this country prior to resale may be imported without a DOT symbol on the sidewall. I have enclosed a copy of a June l8, l98l letter to Mr. Roy Littlefield, which explains in detail the requirements of this narrow exception to the requirements that used tires have a DOT symbol on the sidewall to be legally imported. No Federal safety standard is applicable to retreaded tires for use on motor vehicles other than passenger cars. They may be imported without certification of compliance by the retreader. However, these tires must have a tire identification number marked on the sidewall, per the requirements of 49 CFR Part 574. Your first question is whether it is permissible to import the type of tire casing at issue. As indicated above, new tires for use on school buses may not be imported without the DOT symbol. However, it is our opinion that the casings at issue are materials needing further manufacturing operations to become completed items of motor vehicle equipment, rather than finished items of motor vehicle equipment (tires which could lawfully be used or sold as they are). This opinion is based on the fact that the casings are being imported as slicks, which generally cannot be used on the public highways under state laws since they have no tread, and since the casings are being imported for purposes of recapping. Your second question is whether the casings at issue meet Department of Transportation standards. A key issue in answering this question is whether the tires are considered to be retreaded tires or new tires subject to Standard No. ll9. It is our opinion that any tires manufactured by applying new tread to new casings are considered new tires rather than retreaded tires, and are subject to the same requirements as any other new tires. The National Highway Traffic Safety Administration defines 'retreaded' as 'manufactured by a process in which a tread is attached to a casing.' The term 'casing' is defined as 'a used tire to which additional tread may be attached for the purpose of retreading.' See 49 CFR Part 57l.ll7 and 49 CFR Part 574.3(b). In the situation you described in your letter, the casings were not used tires at the time the 'recapping' took place. Instead, they were simply new tires (originally designed for use on a rubber tire train) which were imported for recapping purposes. These casings would not be considered used tires until they have actually been used (presumably on a train prior to importation, or on the highway, with the new tread attached, in the United States.) Since the tires at issue were not used tires at the time they were recapped, they are not retreaded tires but are instead new tires, subject to Standard No. ll9. The tires would appear not to comply with Standard No. ll9, given the absence of the DOT symbol. Your letter states that the original manufacturer of the tires has stated that the tires are not suitable by any means for highway use. If the tires are not suitable for highway use after they have been recapped, they may contain a safety-related defect. See l5 U.S.C. l4ll et seq. We note that the defect provisions of the National Traffic and Motor Vehicle Safety Act apply to items of motor vehicle equipment regardless of whether there is an applicable safety standard. We hope this information is helpful, and we are referring your letter to our Office of Enforcement. Sincerely, Erika Z. Jones Chief Counsel"; |
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ID: aiam0940OpenMr. James Tydings, Chief Engineer, Thomas Built Buses, Inc., 1408 Courtesy Road, P. O. Box 1849, High Point, NC 27261; Mr. James Tydings Chief Engineer Thomas Built Buses Inc. 1408 Courtesy Road P. O. Box 1849 High Point NC 27261; Dear Mr. Tydings: This is in response to your recent inquiries to Berkley Swee concerning Federal Motor Vehicle Safety Standards Nos. 101 and 108.; You ask whether S4.2.2 of Standard No. 101 applies to push-pul switches. This paragraph requires identification for the extreme positions of any heating and air conditioning system control that regulates a function over a quantitative range, and you state that you currently do not indicate the quantitative range for the heater switches.; S4.2.2 does apply to push-pull switches, and I enclose a notice tha the agency published on December 3, 1971, clarifying our intent. A legend such as 'push off' and 'pull high' would be sufficient to meet the requirements of Standard No. 101. You would not have to redesign your switch cabinet to provide a slide or lever-type switch.; You have also asked whether the school bus lighting description on you attached pages numbered 34 and 35 is 'legal'. The system as described conforms to the requirements of Standard No. 108 for the items listed.; Sincerely, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam1652OpenMr. H. (Speedy) Hirai, Technical Representative, Toyo Kogyo Co., Ltd. USA, 23777 Greenfield Road, Suite 462, Southfield, MI 48075; Mr. H. (Speedy) Hirai Technical Representative Toyo Kogyo Co. Ltd. USA 23777 Greenfield Road Suite 462 Southfield MI 48075; Dear Mr. Hirai: This is in response to your letter of October 18, 1974, in which yo ask whether you must supply consumer information concerning a vehicle whose motor is modified by a high-altitude kit. Further, you wish to know whether the acceleration and passing ability tests required by the regulation must be carried out at the barometric pressure required by section 575.106(d)(1)(vi).; It is our view that you must submit consumer information that meets al the requirements of Part 575, including those relating to barometric pressure, as they apply to these vehicles. Nonetheless, this does not prohibit your also including, separate from the required information, the performance characteristics of the vehicle at the altitude for which it has been modified. While we are aware that vehicles modified for high-altitude performance might not initially be sold at low altitudes, the highly mobile nature of automobile use makes it appropriate that owners be aware of their performance at the lower altitudes at which many of them will be driven and sold after their first purchase.; Yours truly, Richard B. Dyson, Acting Chief Counsel |
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ID: aiam4000OpenMr. Thomas J. Burke, Vice President - Domestic Sales, Hess & Eisenhardt Armoring Company, 8959 Blue Ash Road, Cincinnati, OH 45242; Mr. Thomas J. Burke Vice President - Domestic Sales Hess & Eisenhardt Armoring Company 8959 Blue Ash Road Cincinnati OH 45242; Dear Mr. Burke: Thank you for your letter of July 3, 1985, to Mr. Burdette and Mr Brownlee concerning a new automobile safety package your company is developing. Your letter was referred to my office for reply. You described your product as a number of modifications to a vehicle to improve its security. The modifications include changes to the windows, tires, doors, and fuel tank. I hope the following discussion explains how our regulations would affect your product.; The National Traffic and Motor Vehicle Safety Act authorizes th National Highway Traffic Safety Administration (NHTSA) to issue Federal Motor Vehicle Safety Standards for new motor vehicles and items of motor vehicle equipment. Under that authority, NHTSA has issued vehicle safety standards on a wide variety of subjects, including on tires, windows, doors and fuel tanks. I am enclosing an information sheet explaining how you can obtain copies of our standards. A manufacturer of new vehicles must certify that its vehicles conform to the requirements of all applicable safety standards. Under our certification regulation, Part 567, *Certification* (49 CFR Part 567), a person who modifies a vehicle prior to its first sale to the consumer is considered an alterer.' Part 567.7 requires vehicle alterers to certify that the vehicle, as altered, conforms to all of our safety standards. Thus, if your company is modifying vehicles with your security package prior to their first sale to the consumer, it must certify that the vehicles, as altered, conform with all applicable standards. Any person who fails to comply with our certification regulations is subject to civil penalties under the Vehicle Safety Act.; If your company is modifying used vehicles, then its actions would b affected by section 108(a)(2)(A) of the Vehicle Safety Act (15 U.S.C. S1397(a)(2)(A)), which was added to the Act in 1974 to address the problem of persons tampering with safety equipment installed on a motor vehicle. Section 108(a)(2)(A) provides, in part, that:; >>>No manufacturer, distributor, dealer, or motor vehicle repai business shall knowingly render inoperative, in whole or part, any device or element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with an applicable Federal motor vehicle safety standard.....<<<; Thus, a manufacturer, distributor, dealer, or motor vehicle repai business making the modifications you describe must ensure that those modifications do not render inoperative' the compliance of the vehicle with any safety standard. The Vehicle Safety Act provides for civil penalties for persons that render inoperative' an element of a safety standard.; I hope this information is of assistance to you. If you have furthe questions, please let me know.; Sincerely, Jeffrey R. Miller, Chief Counsel |
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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.