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: aiam0307OpenMr. Colin Calvert, Marketing Manager, FSC Corporation, 6707 Electronics Drive, Springfield, VA 22151; Mr. Colin Calvert Marketing Manager FSC Corporation 6707 Electronics Drive Springfield VA 22151; Dear Mr. Calvert: Please excuse the delay in responding to your letter of January 14 1971. It was inadvertently misplaced. In your letter you requested that I comment whether your system fulfills the requirements of Part 574, the Tire Identification and Record Keeping Regulation.; I am sure you will appreciate the fact that the Administration canno approve each of the various systems developed. Your system, upon a cursory review, appears adequate, however, the regulation speaks for itself concerning the actual requirements.; Sincerely, Lawrence R. Schneider, Acting Chief Counsel |
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ID: aiam5105OpenMr. Daniel K. Upham President Sys Tek Corporation 444 N. Zachary, Suite 111 Moorpark, CA 93021; Mr. Daniel K. Upham President Sys Tek Corporation 444 N. Zachary Suite 111 Moorpark CA 93021; "Dear Mr. Upham: This responds to your letter of December 9, 1992, wit respect to whether a 'portable lighted message display using L.E.D. technology' is permissible under Federal law. The product would be sold in the aftermarket. As you indicate, ' i t will be either battery powered or it will be powered using the vehicle power source via cigarette lighter or directly to the car's electrical harness.' It will be installed in either the side rear or rear window. We assume that battery-powered devices, and those activated through the cigarette lighter, are so simple that the vehicle owner can install and use the device without resorting to the assistance of others. Under this circumstance, there is no restriction that applies to this device under the laws administered by this agency. Nevertheless, the device may be subject to restrictions imposed by a State in which it is operated. However, if attaching the device to the car's electrical harness is a task that may be performed by a person other than the vehicle owner, a different consideration applies. A manufacturer, dealer, distributor, or motor vehicle repair business may not install the device if it renders inoperative, in whole or in part, any device or element of design installed in accordance with a Federal motor vehicle safety standard. Examples of equipment added pursuant to a Federal standard and that could be affected by the sign board are the stop lamps, both center highmounted and conventional, and the inside rear view mirror. I enclose a copy of an interpretation of the agency dated August 17, 1989, to Mr. Alan S. Eldahr, and call your attention to our views on impairment by message boards expressed on the second page. This letter also provides the address of an organization that you may consult on applicable State laws. Installation of the message board in a side rear window by a manufacturer, distributor, dealer, or motor vehicle repair business would appear permissible. The only required side lighting equipment are front and rear lamps and reflectors, intended to mark the extremities of the vehicles, and we do not believe that their function would be negatively affected by installation of the message board. Sincerely, Paul Jackson Rice Chief Counsel Enclosure"; |
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ID: aiam1845OpenMr. Dave Bickel, Product Engineering, Ventline, Inc., P.O. Box 308, Bristol, IN 46507; Mr. Dave Bickel Product Engineering Ventline Inc. P.O. Box 308 Bristol IN 46507; Dear Mr. Bickel: This is in reply to your letter of February 27, 1975, regarding the us of rubber-modified polypropylene plastic in a roof ventilator which you manufacture. You enclose a sample of the material.; A plastic material used in the roof ventilator of a motor home mus meet the requirement of Motor Vehicle Safety Standard No. 205 (49 CFR S 571.205). Our conclusion is based on the fact that ANS Standard Z26.1-1966, which is incorporated into the Federal standard, includes ventilators and openings in the roof of motor vehicles as locations in which glazing materials meeting the requirements of the standard are directed to be used. Any of the materials specified in ANS Z26, and the plastic materials added to the standard (items 12 and 13) on November 11, 1972, may be used in a roof ventilator of a motor home. We would consider such a ventilator to be a window' of the motor home.; The NHTSA has in the past amended Standard No. 205 to permit the use o new materials in vehicle locations following a manufacturer's petition for such an amendment. It appears from your letter that the use of polypropylene in roof ventilators would not create a safety hazard. However, in order for us to consider a change in the standard it will be necessary for you to provide us with information on the performance of this material. One way that manufacturers have provided us this information in the past is to have the material tested to the least restrictive requirements of the standard for any material which the standard permits to be used in the location desired.; I have enclosed a copy of NHTSA procedural rules (49 CFR Part 553 containing information on submitting a petition for rulemaking. Such a petition should contain the information I have referred to regarding the performance of polypropylene.; In your letter you ask for a code number should we determine that th material must conform to Standard No. 205. A code number, however, is issued only to a prime glazing material manufacturer, who is one who either fabricates, laminates, or tempers the glazing material. The request for such a code number must be made directly by the prime glazing material manufacturer.; Sincerely, James C. Schultz, Chief Counsel |
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ID: aiam3878OpenMr. Eddie Cole, Answer Products, Inc., 27967 Beale Court, Valencia, CA 91355; Mr. Eddie Cole Answer Products Inc. 27967 Beale Court Valencia CA 91355; Dear Mr. Cole: This responds to your letter regarding the importation of motorcycl helmets by your company from Italy.; Federal Motor Vehicle Safety Standard No. 218, *Motorcycle Helmets* applies to helmets designed for use by motorcyclists and other motor vehicle users. You stated in your letter that there is a DOT *approval sticker* on the helmet and that your company's name is clearly displayed on the helmet. Standard No. 218 requires that each helmet be permanently and legibly labeled with the manufacturer's name or identification, model designation, size, month and year of manufacture, and the symbol DOT. The DOT symbol does not indicate approval of any helmet by the Department of Transportation. Instead, the DOT symbol represents the manufacturer's certification that the helmet meets all the requirements of Standard No. 218. A copy of this standard is enclosed for your information.; As an importer, your company is also considered a manufacturer unde the provisions of the National Traffic and Motor Vehicle Safety Act which is administered by this agency. Therefore, either your company's name or the Italian manufacturer's name should be affixed to each helmet. Your company and the Italian manufacturer are both responsible for any defect in the helmet or failure to comply with the standard's requirements.; You asked about other regulations of which you should be aware. Copie of these are enclosed:; >>>49 CFR Part 551-- *Procedural Rules* (Subpart D--Service of proces on foreign manufacturers and importers).; 49 CFR Part 566--*Manufacturer Identification*.<<< If you need additional information, please contact this office. Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam0757OpenMr. Satoshi Nishibori, Engineering Representative, Nissan Motor Co., Ltd., 560 Sylvan Avenue, Englewood Cliffs, NJ, 07632; Mr. Satoshi Nishibori Engineering Representative Nissan Motor Co. Ltd. 560 Sylvan Avenue Englewood Cliffs NJ 07632; Dear Mr. Nishibori: This is in reply to your letter of June 9, 1972, concerning th proposed amendment to paragraph S4.2 of Motor Vehicle Safety Standard No. 302 (36 F.R. 9565, May 26, 1971). As we understand your question it is, when surface, underlying, or padding and cushioning materials are glued together in particular vehicle components, should you test with the glue applied to the contact points between the materials.; The proposed revision of paragraph S4.2 together with paragraph S5. o the standard contemplates the testing of composites with the individual materials joined together, as they appear in the vehicle. Materials glued together would be tested in that configuration during NHTSA compliance tests, and the glue would be tested as part of the composite.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam2290OpenMr. John Eckhold, Automotive Safety Director, Ford Motor Company, The American Road, Dearborn, MI 48121; Mr. John Eckhold Automotive Safety Director Ford Motor Company The American Road Dearborn MI 48121; Dear Mr. Eckhold: I am writing to inform you that the National Highway Traffic Safet Administration (NHTSA) will, for a limited time, refrain from enforcing one portion of 49 CFR Part 575, *Consumer Information Regulations*.; Subpart B of Part 575 specifies certain items of consumer informatio that apply to motor vehicles and their tires. Section 575.6 in Subpart A requires this information to be delivered to first purchasers (paragraphs (a) and (b)), made available to prospective purchasers (paragraph (c)) and submitted to the NHTSA (paragraph (d)). In particular, S 575.6(d) requires that:; >>>Each manufacturer of motor vehicles...shall submit to th Administrator 10 copies of the information specified in Part B of this part that is applicable to the vehicles or tires offered for sale, at least 30 days before that information is first provided for examination by prospective purchasers pursuant to paragraph (c) of this section.<<<; I understand that the strike by the United Rubber Workers has, b cutting off the supply of new tires, created an emergency situation within the motor vehicle industry, making it difficult for a manufacturer to know more than several days before it completes a vehicle which tires will be available for installation on the vehicle. I understand further that the provision of such information to the NHTSA 30 days before it is made available to prospective purchasers has become virtually impossible.; In view of the impracticability under the current circumstances of th 30-day-notice requirement, the NHTSA has concluded that enforcement of the requirement at this time is inappropriate. Accordingly, with respect to vehicles offered for sale during the strike and the 60-day period following its settlement, the NHTSA will refrain from enforcing the 30-day-notice requirement in S 575.6(d). Submittals of information to the agency must continue to be made, however, not later than the time the information is made available to prospective purchasers. With respect to vehicles that will be offered for sale at the expiration of the 60-day period, the NHTSA expects to begin receiving submittals after the thirtieth day following settlement of the strike.; Please note that the requirements of paragraphs (a), (b), and (c) of 575.6, as well as Federal Motor Vehicle Safety Standard No. 110, *Tire Selection and Rims--Passenger Cars*, are not affected by this letter.; Sincerely, James B. Gregory, Administrator |
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ID: aiam5555OpenMr. C. Rufus Pennington, III Margol & Pennington, P.A. Suite 1702 American Heritage Tower 76 South Laura Street Jacksonville, FL 32202; Mr. C. Rufus Pennington III Margol & Pennington P.A. Suite 1702 American Heritage Tower 76 South Laura Street Jacksonville FL 32202; "Dear Mr. Pennington: This responds to your letter concerning the rea seats of a 1979 Porsche 911 SC, which were not equipped with any type of seat belt. You asked two questions relating to whether these seats should have been equipped with seat belts. Your questions are addressed below. 1. Did the manufacturer's designation of 'two front' passenger seats eliminate any obligation on the part of the manufacturer to provide seat belts in the rear seats under Federal Motor Vehicle Safety Standard 208? As explained below, a manufacturer's designation that a vehicle has two front seats does not eliminate the obligation to provide seat belts at rear seats, if those positions are 'designated seating positions.' By way of background information, The National Highway Traffic Safety Administration (NHTSA) is authorized to issue Federal motor vehicle safety standards applicable to the manufacture and sale of new motor vehicles and items of motor vehicle equipment. NHTSA has exercised this authority to establish Federal Motor Vehicle Safety Standard No. 208, Occupant Crash Protection (49 CFR 571.208), which specifies performance requirements for the protection of vehicle occupants in crashes. Standard No. 208 required passenger cars manufactured on or after September 1, 1973 and before September 1, 1986, to have either a Type 1 (lap) or Type 2 (lap/shoulder) seat belt assembly at each rear 'designated seating position.' The term 'designated seating position' is defined at 49 CFR 571.3. For vehicles manufactured before September 1, 1980, the term 'designated seating position' was defined as: any plan view location intended by the manufacturer to provide seating accommodation while the vehicle is in motion, for a person at least as large as a fifth percentile adult female, except auxiliary seating accommodations such as temporary or folding jump seats. In a May 22, 1978, notification to vehicle manufacturers, the agency stated that manufacturers are responsible for determining the number of seating positions that are in the vehicle. The agency also stated: This does not mean, however, that the manufacturer's designation will be accepted by the agency if there are additional, obvious seating positions that are likely to be used by occupants while the vehicle is in motion. The agency unquestionably intends to require protection for all vehicle occupants. Thus, a manufacturer's specification that a vehicle has two front seats did not eliminate Standard No. 208's requirement for a seat belt assembly at each rear seat, if those locations met the above definition. 2. Did the Porsche 911 SC comply with, or did it violate, the requirements of Federal Motor Vehicle Safety Standard 208? NHTSA cannot make a determination as to whether a vehicle complied with applicable safety standards outside a compliance proceeding. However, I can advise you of the factors the agency would look at to determine if the rear locations are designated seating positions. If those locations are designated seating positions, they should have been equipped with a seat belt assembly when originally manufactured. The May 22, 1978, notice provides a good summary of the agency's position. That notice states: the agency will consider any position ... capable of accommodating a person at least as large as a fifth percentile adult female to be a 'designated seating position', if the overall seat configuration and design is such that the manufacturer knows the position is likely to be used as a seating position while the vehicle is in motion. I note that the hip breadth of a sitting fifth percentile female is approximately 13 inches, and the sitting height is approximately 31 inches. These are the measurements NHTSA would consider in determining whether a position is capable of accommodating a fifth percentile female. I hope this information has been helpful. If you have other questions or need some additional information, please contact Mary Versailles of my staff at this address or by phone at (202) 366-2992. Sincerely, John Womack Acting Chief Counsel Enclosures"; |
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ID: aiam1516OpenMr. Ronald C. Dobbyn, Program Manager, Law Enforcement Standards Laboratory, U.S. Department of Commerce, National Bureau of Standards, Washington, D.C. 20234; Mr. Ronald C. Dobbyn Program Manager Law Enforcement Standards Laboratory U.S. Department of Commerce National Bureau of Standards Washington D.C. 20234; Dear Mr. Dobbyn: Your May 1, 1974, letter to Mr. Clyde Roquemore has been forwarded t me for reply. You ask for our comments on a draft standard on crash helmets developed by the National Bureau of Standards' Law Enforcement Standards Laboratory for the National Institute of Law Enforcement and Criminal Justice, which was enclosed in your letter. You point out that this draft standard 'is intended for voluntary use by state and local law enforcement agencies in their equipment selection and procurement process.'; Section 103(d) of the National Traffic and Motor Vehicle Safety Act o 1966, 15 U.S.C. 1392(d), provides:; >>>Whenever a Federal motor vehicle safety standard established unde this title 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. Nothing in this section shall be construed to prevent the Federal Governmnent or the government of any State or political subdivision thereof from establishing a safety requirement applicable to motor vehicles or motor vehicle equipment procured for its own use if such requirement imposes a higher standard of performance than that required to comply with the otherwise applicable Federal standard.<<<; Pursuant to his statutory authority under the National Traffic an Motor Vehicle Safety Act, the Administrator of the National Highway Traffic Safety Administration (NHTSA) established Federal Motor Vehicle Safety Standard No. 218, *Motorcycle Helmets*, 49 CFR Part 571.218, on August 9, 1973. Since Standard No.218 establishes minimum performance requirements for motorcycle helmets manufactured for use by motorcyclists and other motor vehicle users, any differing State or municipal requirements in the form of laws or regulation applicable to the design or performance of motorcycle helmets which have a bearing on safety would be void in accordance with the preemption provision of the Act cited above.; On the other hand, if a law enforcement agency (or any other person wishes to establish higher requirements for its own procurement purposes, for helmets that nevertheless conform to Federal standards, nothing in the law would prohibit that.; I have enclosed a copy of the National Traffic and Motor Vecle Safet Act of 1966 and copies of each of the four notices issued by the NHTSA on motorcycle helmets. If I can be of any further assistance, please let me know.; Sincerely, Lawrence R. Schneider, Chief Counsel |
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ID: aiam4714OpenMr. George B. Maday President Network USA Inc. 136 Walker St., SW Atlanta, GA . 30313-1326; Mr. George B. Maday President Network USA Inc. 136 Walker St. SW Atlanta GA . 30313-1326; Dear Mr. Maday: This is in reply to your letter with respect to th automatic light switching device whose potential for the U.S. market you are assessing. The device automatically activates the headlamps at a pre-determined (but adjustable) level of darkness. There is a manual override for the operator. I regret the delay in responding. You have asked two questions: 'l. What legislation is in force or pending regarding the mandatory utilization of such daytime running lights for vehicles?' None. The agency once proposed that motor vehicles be equipped with daytime running lamps as an option, but it terminated rulemaking on this subject without taking action. '2. What regulations, standards, forms, etc. have to be submitted to you or the appropriate agency to ensure that the product meets any U.S. specifications or standards prior to importation. None. There are no Federal motor vehicle safety standards that apply to this item of motor vehicle equipment. However, if you intend it to be installed as an item of original equipment, it must not create a noncompliance with Motor Vehicle Safety Standard No. 108 Lamps, Reflective Devices, and Associated Equipment, or result in an impairment of the effectiveness of the lighting equipment that the standard requires. For example, the standard requires the taillamps to be activated when the headlamps are activated. Therefore, when your device activates the headlamps, the taillamps must also be activated. Though expressed in somewhat different terms, the acceptability of your device in the aftermarket is governed by a similar consideration: it may not be installed by a motor vehicle manufacturer, distributor, dealer or repair business if the installation would render inoperative any element of design or device installed in accordance with Standard No. 108. The device would remain subject to the laws of any State in which it is sold or operated. We are unable to advise you as to its acceptability under State laws, and recommend that you consult the American Association of Motor Vehicle Administrators (AAMVA), 4600 Wilson Boulevard, Arlington, Va. 22203. Sincerely, Stephen P. Wood Acting Chief Counsel; |
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ID: aiam1146OpenMr. Louis C. Lundstrom,Executive Director,Environmental Activities Staff,General Motors Corporation,General Motors Technical Center,Warren, Michigan 48090; Mr. Louis C. Lundstrom Executive Director Environmental Activities Staff General Motors Corporation General Motors Technical Center Warren Michigan 48090; Dear Mr. Lundstrom:#This is in reply to your letter of may 11, 1973 asking for confirmation of your interpretation of paragraph S7.9 of Standard No. 105a in term of General Motors' air vacuum power brake.#Your interpretation is correct. Your system with its 'two separate and independent energy sources in the power head...is equivalents to two entirely duplicate systems', and disconnection of one source at a time would be the correct test procedure under S7.9, provided the requirements of S5.1.3 are satisfactorily met under both conditions.#Sincerely,James E. Wilson,Associate Administrator,Traffic Safety Programs; |
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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.