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 |
|---|---|
| search results table | |
ID: aiam4508OpenMr. R. H. Madison 12814 Asbury Drive Ft. Washington, MD 20744; Mr. R. H. Madison 12814 Asbury Drive Ft. Washington MD 20744; "Dear Mr. Madison: This responds to your March 31, 1988, letter askin for our interpretation of Safety Standard No. 207, Seating Systems, as it applies to a seat installed in a multipurpose passenger vehicle and equipped with a safety belt. You attached a sketch of your seat and asked whether the safety belt assembly is considered to be attached to the seat. You asked this question in order to determine whether the seat would be subject to the specified forces of paragraph S4.2(c) of the standard. The answer is that NHTSA considers the assembly to be attached to the seat. By way of background information, the National Highway Traffic Safety Administration (NHTSA) does not grant approval of motor vehicles or motor vehicle equipment. Under the National Traffic and Motor Vehicle Safety Act, it is the responsibility of the manufacturer to ensure that its vehicles or equipment comply with applicable requirements. The following represents our opinion based on our understanding of the facts provided in your letter. In this regard, I want to note that rendering an opinion in this case was complicated by the fact that your sketch does not show the seat structure and its interrelationship with the vehicle structure and belt anchorage. In your letter, you refer to a vehicle having a 'Belt Attachment Frame' made from steel members attached to the vehicle's structure. You said that, '(r)esting on the Belt Attachment Frame is a plywood deck . . . The seat cushion rests on but is not otherwise attached to the deck. The seat belt attachments pass through the deck and are secured to the Belt Attachment Frame. Other portions of the seat or its supporting structure might rest on and contact the Belt Attachment Frame and might extend to or beyond it. However, except for the deck, no part of the seat or its structural members would be attached to the Belt Attachment Frame.' (Emphasis added.) The answer to your question depends on whether the Belt Attachment Frame is considered part of the seat. Based on the information you provide, we conclude that the Belt Attachment Frame is part of the seat itself. According to your letter, the deck for the seat cushion is attached to and supported by the Belt Attachment Frame, it appears that the Belt Attachment Frame is a necessary and functional part of the seat structure. Since we interpret the Belt Attachment Frame to be a part of the seat, and since the seat belt assembly loads will be transferred to the Frame in the event of a crash, we consider the seat belt assembly to be attached to the seat, for purposes of testing the seat under S4.2(c) of Standard No. 207. Please contact my office if you have further questions. Sincerely, Erika Z. Jones Chief Counsel"; |
|
ID: aiam3737OpenMr. H. Le Guen, Laboratory Director, Union Technique de L'Automobile du Motorcycle et du Cycle, Autodrome de Linas- Montlhery, Linas, 91310 Montlhery, France; Mr. H. Le Guen Laboratory Director Union Technique de L'Automobile du Motorcycle et du Cycle Autodrome de Linas- Montlhery Linas 91310 Montlhery France; Dear Mr. Le Guen: This is in reply to your letter of July 27, 1983, to Mr. Vinson of thi office asking several questions with respect to the amendment of Standard No. 108, June 2, 1983, which permits semi-sealed replaceable bulb headlamps.; First, you mention certain sealing specifications, contrasting the with references to designed openings, and ask for our comments on this. Although the design that Ford intends to use is not a vented system, the amendment does not specify or prohibit either vented or unvented systems. A vented system using the standardized replaceable light source and the O-ring seal is permissable (sic) if the headlamp passes all the recently adopted environmental tests.; With reference to your further questions, there are no tolerances o the dust test. You have also asked whether, assuming that a European type headlamp using the new light source 'passes all tests mentioned in the amendment to F.M.V.S.S. 108, would it get D.O.T. approval?' If the lens- reflector unit is bonded, and if with the light source inserted the lamp meets U.S. photometric requirements and all environmental tests specified in the amendment, then the manufacturer of the lamp may apply the D.O.T. symbol to it. This is the certification that the lamp meets all applicable U.S. Federal motor vehicle safety standards. Under this self- certification process, the manufacturer, rather than D.O.T., approves the lamp for sale.; Finally, you have asked who will manufacture the new bulb and where yo might be able to obtain test samples. Ford's initial supplier will be Sylvania/GTE, and you may write GTE Products Corp., West Main Street, Hillsboro, NH 03249, Attn: Mr. Richardson.; I hope this answers your questions. Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam2825OpenMr. Warren L. VanderLinden, Sales Manager, Minnesota Motor Company, P.O. Box 505, Fergus Falls, MN 56537; Mr. Warren L. VanderLinden Sales Manager Minnesota Motor Company P.O. Box 505 Fergus Falls MN 56537; Dear Mr. VanderLinden: Administrator Claybrook has asked me to respond to your recent lette concerning the installation of safety belts in the cargo area of a van vehicle for the purpose of securing wheelchair patients. Apparently, your legal counsel has advised you that such installation might be prohibited by Federal law or might give rise to private litigation problems in the future.; In answer to your questions, there is nothing under Federal law or th Federal motor vehicle safety standards that would prevent the installation of safety belts in the cargo area of a van to secure wheelchairs. In fact, Administrator Claybrook and the National Highway Traffic Safety Administration encourage you to make the installation requested by the senior citizens home. The safe transportation of disabled persons is currently a serious problem and every effort should be made to ameliorate the situation.; The only instance in which you would have any responsibilities unde Federal law would be an installation of additional safety belts prior to first purchase of the van by a consumer. In that case you would be a vehicle alteror, (sic) and under our certification regulations you would be required to place an additional label on the vehicle specifying that, as altered, the vehicle is still in compliance with all applicable safety standards (49 CFR 567.7, copy enclosed). For example, you should not destroy the vehicle's compliance with our Fuel System Integrity standard by penetrating the gas tank with the safety belt anchorage bolts.; Concerning your liability in private litigation, the general provision of negligence law would be applicable, as with any maintenance, repair or alteration done by a motor vehicle repair business. I must defer to the advice of your own counsel on that matter, however.; Once again, the agency does encourage the installation of safety belt for the securement of wheelchairs, since the disabled are seriously endangered without some type of restraint to protect them in a crash. Further, I believe that your fears of liability should be minimal as long as the installation is accomplished with normal consideration and due care.; Please contact Hugh Oates of my office if you have any furthe questions (202-426- 2992).; Sincerely, Joseph J. Levin, Jr., Chief Counsel |
|
ID: aiam0818OpenMr. Louis J. Zsoka, President, Garfield Rubber Products, Inc., 13532 Broadway Avenue, Garfield Heights, OH, 44125; Mr. Louis J. Zsoka President Garfield Rubber Products Inc. 13532 Broadway Avenue Garfield Heights OH 44125; Dear Mr. Zsoka: This is in reply to your letter of July 13, 1972, concerning th applicability of Federal Motor Vehicle Safety Standard (FMVSS) No. 302 to your sponge rubber weather-stripping for replacement.; Standard No. 302 does not apply to replacement parts or aftermarke materials. You are correct in your observation that sponge rubber weather-stripping is not included in the list of motor vehicle interior materials to which Standard No. 302 applies.; Sincerely, Robert L. Carter, Associate Administrator, Motor Vehicl Programs; |
|
ID: aiam4158OpenMr. Roger Williams, President, Technical Hallmark Enterprises, Inc., P.O. Box 103, Moss Point, MS 39563; Mr. Roger Williams President Technical Hallmark Enterprises Inc. P.O. Box 103 Moss Point MS 39563; Dear Mr. Williams: This is in reply to your letter asking about regulations applicable t the 'new lights that are now being seen on the trunk lids, and the rear windows of new automobiles'.; The specific legal name for this light is 'center high-mounted sto lamp.' It was optional for use as original equipment on passenger cars manufactured between August 1, 1984 and September 1, 1985. It has been mandatory original equipment since them. The Federal regulation that requires it is Federal Motor Vehicle Safety Standard No. 108 *Lamps, Reflective Devices, and Associated Equipment* issued by the National Highway Traffic Safety Administration of the Department of Transportation. This standard specifies color, minimum illuminated lens area, mode of operation, etc. for original equipment, and for equipment intended to replace that original equipment. The standard does not cover center high-mounted stop lamps intended for use on cars that never had them, and a manufacturer of such aftermarket motor vehicle equipment is subject only to State laws on their design, installation, and use. We encourage aftermarket manufacturers to follow the Federal standard so that the full potential of the lamp may be realized. This means that the lamp should be steady- burning rather than pulsating, and that the lens not have logos, trademarks, or other markings on it to interrupt the transmission of light from the lamp. The standard does not specify the shape of the lamp but virtually all to date have been rectangular (photos of the 1984 Cadillac Allante show a circular one), and some have exceeded the minimum requirement of a lens area of at least 4 1/2 square inches.; Noting your interest as a prospective manufacturer of these devices, enclose a copy of Standard No. 108. Sections 4.1.1.41 (page 218), Section 4.3.1.8 (page 227) and Table III (page 256) provide the relevant requirements for center high-mounted stoplamps. Should you proceed to manufacture aftermarket lamps, you would be subject to the agency's notification and remedy procedures should a safety related defect occur in them. Otherwise, you would appear to be subject only to State laws.; Sincerely, Erika Z. Jones, Chief Counsel |
|
ID: aiam3367OpenMr. G. Montgomery Spindler, Uniroyal, Inc., 1700 K Street, N.W., Washington, DC 20006; Mr. G. Montgomery Spindler Uniroyal Inc. 1700 K Street N.W. Washington DC 20006; Dear Mr. Spindler: This is in response to your letter of October 10, 1980, requestin clarification of the explanation of Treadwear grading in Figure 2 of the Uniform Tire Quality Grading (UTQG) Standards (49 CFR S 575.104). You ask whether the explanation can be interpreted to mean that the relative treadwear performance of different tires on the UTQG test course in San Angelo, Texas will be consistent with the relative performance of the tires when driven under comparable conditions on other roads.; In experimental testing leading to promulgation of the UTQG regulation the National Highway Traffic Safety Administration (NHTSA) tested the treadwear of various tire lines not only on the San Angelo course but on roads in other parts of the country. The agency concluded that the UTQG grades established for different tires in testing on the San Angelo course accurately represent the relative performance of the tires obtainable on roads elsewhere in the United States, assuming that the tires to be compared are run under identical conditions.; The statement in Figure 2 of the UTQG regulation that a tire graded 15 would wear one and one-half times as well on the government course as a tire graded 100 was not intended to suggest that the tire would not wear one and one-half times as well on another course, if conditions of use were controlled. The term 'relative performance' in Figure 2 refers to the performance of tires in comparison to other tires, and the term 'norm' refers to the consistently obtainable relative performance of tires when tested under controlled conditions. Thus, the explanation indicates that, although the relative performance of different tires will be consistent when the tires are tested under controlled conditions, this relative performance may not be obtainable in actual use, if one tire is subjected to more severe road or weather conditions, abusive driving or improper maintenance.; NHTSA will provide confidential treatment for your October 10, 1980 letter.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam5319OpenMr. Michinori Hachiya Director, Technical Affairs Nissan North America, Inc. 750 17th Street, N.W. Suite 901 Washington, D.C. 20006-4607; Mr. Michinori Hachiya Director Technical Affairs Nissan North America Inc. 750 17th Street N.W. Suite 901 Washington D.C. 20006-4607; Dear Mr. Hachiya: This responds to your request for an interpretatio of the theft prevention standard (49 CFR part 541) as it would apply to high theft passenger motor vehicles and their replacement parts from model year (MY) 1996 and thereafter. Because the agency has not yet published regulations for MY 1996 high theft lines and thereafter, we are unable to answer your specific questions. As a result of the 'Anti Car Theft Act of 1992' (ACTA), certain changes must be made to the theft prevention standard. In its October 25, 1993 semiannual regulatory agenda, NHTSA listed its proposed rulemakings to implement the ACTA. (See 58 FR 56734 et seq.) In a Federal Register document of January 6, 1994 (59 FR 796), NHTSA stated it intended that the new ACTA-mandated procedures apply to high theft lines beginning in MY 1996. As indicated in the October 1993 semiannual agenda, NHTSA will shortly issue a notice of proposed rulemaking to amend the theft prevention standard. We believe the NPRM will address the issues you raise. If the NPRM does not address them, you will be able to discuss any questions you may have in your comments on the rulemaking submitted to NHTSA during the public comment period. If you have any questions, please contact Dorothy Nakama of my staff at (202) 366-2992. Sincerely, John Womack Acting Chief Counsel; |
|
ID: aiam2126OpenInterps. File, Part 575.104; Interps. File Part 575.104; Subject: Telephone call from Patrick Raher, Esq. of Hogan & Hartson Esqs., representing Mercedes-Benz, on September 15, 1975; The subject telephone call was referred to me by Mark Schwimmer. explained to the caller the status of the UTQGS litigation, the briefing schedule, and the meaning of the stay order. He stated that Mark Schwimmer had read to him the text of Judge Weick's stay order.; The caller's questions and my responses were essentially the same a those covered in my August 27, 1975 memorandum in reference to telephone calls from Yokohama Tire Company and Transportation, Inc.; From: Allan Kam, Attorney |
|
ID: aiam2576OpenHonorable Warren G. Magnuson, Chairman, Committee on Commerce, Science, and Transportation, United States Senate, Washington, DC 20510; Honorable Warren G. Magnuson Chairman Committee on Commerce Science and Transportation United States Senate Washington DC 20510; Dear Mr. Chairman: This is in response to your letter of April 11, 1977, expressing you concern over a perceived pattern of delay in the implementation of the Federal motor vehicle safety and damageability standards. You expressed particular concern about the National Highway Traffic Safety Administration's (NHTSA) recent proposal to delay for one year the effective date for the second phase of requirements in the Part 581 bumper standard.; I am aware that there have been instances in the past when th effective dates of final rules have been delayed or when the final rules have been modified or rescinded. I do not intend to pass judgment on whether the actions of my predecessors in those particular instances should have been taken. However, I agree with your view that changes in the substantive requirements and effective dates of final rules can have undesirable effects and should be avoided if possible.; I believe that the most effective means of reducing the necessity fo changes in final rules is to ensure that each proposed rule is thoroughly examined prior to issuance in final form. Every significant issue should be explored and comments and data from all interested persons should be carefully analyzed. Where gaps in our knowledge appear, the information-gathering authority given the NHTSA should be utilized. For example, extensive use of that authority has been recently made in connection with rulemaking under Title V of the Motor Vehicle Information and Cost Savings Act, as amended, to establish average fuel economy standards for model year 1981-1984 passenger automobiles. By making more careful analyses and obtaining needed information, we can minimize the possibility that belatedly discovered information or circumstances will necessitate a change in our requirements or implementation schedules.; Our taking these steps does not, of course, mean that there will no continue to be some instances in which effective dates and substantive requirements are changed. We must be responsive to new information and changed circumstances to ensure that our requirements continue to meet all statutory criteria. There will still be problems not completely foreseen by the agency or the manufacturers. New concerns such as those relating to fuel economy and noise will arise. Finally, there may be a need to adjust our standards to accommodate changes in other types of motor vehicle standards.; As to the second phase of the bumper requirements, I am currentl reviewing the reasons for the proposal to delay, and the comments on the notice are being analyzed. The statute, under which Part 581 was promulgated, requires that interested persons be given an opportunity for oral presentation of comments prior to the issuance of any amendment to the bumper standard. Thus, my decision on the proposed amendment will be made following a public hearing which will be scheduled in the near future.; Sincerely, Joan B. Claybrook |
|
ID: aiam2063OpenMr. Andrew W. Brainerd, Brainerd & Bridges, 1 North LaSalle Street, Chicago, Illinois 60602; Mr. Andrew W. Brainerd Brainerd & Bridges 1 North LaSalle Street Chicago Illinois 60602; Dear Mr. Brainerd: #This is in response to the May 26, 1975, petitio of your client, Kugelfischer Georg Schaefer & Co., for an amendment of the banding requirement of Federal Motor Vehicle Safety Standard No. 106-74, *Brake Hoses*. #The National Highway Traffic Safety Administration has granted the petitions of General Motors Corporation and Ford Motor Company to delete the banding requirement. A proceeding respecting the issuance of a notice of proposed rulemaking has been commenced. Because the amendment requested by your client is inconsistent with the deletion of the banding requirement, in the strict sense, that petition is hereby denied. You may find, however, that the change now being developed in our rulemaking proceedings will be satisfactory to your client. #Sincerely, Robert L. Carter, Associate Administrator, Motor Vehicle Programs; |
|
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.