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: aiam0974OpenMr. Tatsuo Kato, Engineering Representative, Nissan Motor Company, Ltd., 560 Sylvan Avenue, Englewood Cliffs, NJ 07632; Mr. Tatsuo Kato Engineering Representative Nissan Motor Company Ltd. 560 Sylvan Avenue Englewood Cliffs NJ 07632; Dear Mr. Kato: This is in reply to your letter of January 2, 1973, concernin Truck-Camper loading consumer information requirements.; You have asked whether you have correctly indicated the 'rear end o truck bed' in a drawing of the short body pick- up truck that you attached. The answer is yes. As Mr. Vinson of our staff indicated to Mr. Nishibori when he telephoned on January 9, 1973, 'rear end of truck bed' does not refer to a particular point with the tailgate in either a raised or lowered position. It means, in the words of the preamble of the reissued standard (37 F.R. 26605) 'the point where the identified surface of the camper abuts the rearmost edge surface of the cargo area of the truck, presumably the tailgate in most configurations.'; You also ask if you must meet the requirements of S 575.6 on or afte March 1, 1973. As a manufacturer of a truck that is capable of accommodating a slide-in camper, you must pursuant to 575.6(a) furnish consumer information with each truck manufactured on or after March 1, 1973, at the time the vehicle is offered for sale. Material for examination by prospective purchasers, pursuant to 575.6(b) should be made available at dealer showrooms no later than the date that trucks manufactured on or after March 1, 1973, are first offered for sale by such dealers. The NHTSA has been petitioned to delay the effective date by 60 days and this request is under consideration.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam2949OpenMr. Leon Conner, P.O. Box 1671, San Angelo, TX 76902; Mr. Leon Conner P.O. Box 1671 San Angelo TX 76902; Dear Mr. Conner: We understand that a question has arisen concerning the testing o 'P-type' tires under the traction grading procedures of the Uniform Tire Quality Grading (UTQG) Standards (49 CFR 575.104(f)(2)). Under the terms of the regulation, candidate tires are to be inflated to 24 psi prior to the traction test (49 CFR 575.104(f)(2)(i)(B) and (D), and (f)(2)(viii)), and are to be loaded to 85 percent of the load specified in Appendix A of FMVSS No. 109 (49 CFR 571.109), for the tires' size designation, at a cold inflation pressure of 24 psi (49 CFR 575.104(f)(2)(viii)). However, Appendix A lists cold inflation pressures for 'P-type' tires in kilopascals, with no stated inflation pressure corresponding precisely to 24 psi.; NHTSA chose 24 psi as the stated inflation pressure for UTQG tractio testing since it represents the recommended tire inflation pressure for most passenger cars. In the situation where no cold inflation pressure exactly equivalent to the specified pressure of 24 psi is stated in Appendix A of FMVSS No. 109 for a tire size designation, the tires to be tested are inflated to the pressure, listed for the tire size designation in Appendix A, which is nearest to 24 psi, *i.e.*, 180 kPa for tires with inflation pressures measured in kilopascals. The tires are then loaded to 85 percent of the load specified in Appendix A for the inflation pressure thus determined. The agency plans to issue an interpretive amendment to the regulation clarifying this point.; Sincerely, Joseph J. Levin, Jr., Chief Counsel |
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ID: aiam1666OpenMr. George Davis, B. F. Goodrich Tire Company, 500 South Main Street, Akron, OH 44318; Mr. George Davis B. F. Goodrich Tire Company 500 South Main Street Akron OH 44318; Dear Mr. Davis: We have reviewed the draft defect notification letter delivered to u on November 12, 1974, regarding the safety-related defect in Goodrich's Space Saver Spare Tire. We find that this draft does conform to the requirements of 49 CFR Part 577, 'Defect Notification.'; Yours truly, Richard B. Dyson, Acting Chief Counsel |
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ID: aiam4464OpenMr. M. Arisaka Manager, Automotive Lighting Engineering Dept. Stanley Electric Co. Ltd. 2-9-13, Nakameguro, Meguro-ku Tokyo 153 JAPAN; Mr. M. Arisaka Manager Automotive Lighting Engineering Dept. Stanley Electric Co. Ltd. 2-9-13 Nakameguro Meguro-ku Tokyo 153 JAPAN; Dear Mr. Arisaka: This is in reply to your letter of September 23 1987, with respect to daytime running lamps (DRLs). With reference to the Canadian proposal on this subject, you have noted that it would allow optically combining the DRL with the parking lamp, using dual intensity bulbs within the same housing and covered by the same lens. (As you may be aware, the Canadian government recently issued a final rule which adopted the proposal). You have further noted that the maximum candela output of the parking lamp together with the candela of the DRL will be greater than the maximum permitted for the parking lamp. You believe that under this circumstance the parking lamp does not have to conform to the maximum values specified, and have asked for our opinion of this matter. Under the proposal by the United States, a DRL would have to be a lamp other than a parking lamp (proposed new paragraph S4.6.3(a)), because their brightness is inadequate for use as DRLs. However, the DRL could be incorporated into a multiple function lamp, one of whose functions is to serve as a parking lamp. A lamp with multiple functions must meet all requirements that apply when a specific function is being fulfilled. For example, a lamp that functions both as a parking lamp and a DRL and which is operated in daylight could act as either a DRL or a parking lamp, depending on the intensity of the light emitted, but it would have to meet the photometric requirements for the function being exercised. We cannot really be more specific in answering your questions, because we are still at the proposal stage of the rulemaking process. The final decision could differ. Sincerely, Erika Z. Jones Chief Counsel; |
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ID: aiam0427OpenMr. T. G. Burke, American Jawa Ltd., 185 Express Street, Plainview, LI, NY 11803; Mr. T. G. Burke American Jawa Ltd. 185 Express Street Plainview LI NY 11803; Dear Mr. Burke: This is in reply to your letter of August 17, 1971, inquiring whethe tires for use on racing motorcycles are subject to the Tire Identification and Record Keeping regulation (49 C.F.R. 574).; The regulation applies to 'manufacturers, . . . of new and retreade tires for use on motor vehicles' and, thus, whether the regulation applies to the tires in question depends on whether they are for use on a 'motor vehicle.' If the tires are for use on a racing motorcycle (i.e., a motorcycle which is not manufactured primarily for use on the public streets, roads, and highways), the tires are not considered to be manufactured for use on a 'motor vehicle' and the regulation does not apply to them. We consider a label such as 'For Racing Purposes Only, Not for Highway Use' as evidence of manufacture for off road use.; The execution of an HS-7 form is unnecessary when racing tires ar imported whether or not they are mounted on a racing motorcycle. However, should it be necessary to execute an HS-7 form to expedite importation, Box 8 should be used to indicate that the items being imported are not considered to be for use on a motor vehicle and are not items of motor vehicle equipment.; Sincerely, Lawrence R. Schneider, Acting Chief Counsel |
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ID: aiam4937OpenSue Ellen Russell, Esq. Brand & Lowell 923 Fifteenth Street, NW Washington, DC 20005; Sue Ellen Russell Esq. Brand & Lowell 923 Fifteenth Street NW Washington DC 20005; "Dear Ms. Russell: This responds to your letter of October 24, 1991 concerning Safety Standard No. 210, Seat Belt Assembly Anchorages. You stated that Glaval Corporation, which you represent, recently notified NHTSA of its intention to conduct a notification and remedy campaign to respond to 'an apparent noncompliance with the safety belt anchorage strength requirements as they apply to the rear bench seat in Glaval vans.' According to your letter, these seats contain three designated seating positions, and each seat belt anchorage is 'mounted on the seat, not the floor.' You stated that in the course of evaluating potential remedies, you became aware of an April 9, 1990 interpretation letter sent by this agency to Mr. R.W. Schreyer of Transportation Manufacturing Corporation, in which the agency stated that only floor-mounted anchorages are subject to simultaneous testing. Because the Glaval van bench seat anchorages were tested simultaneously in NHTSA's compliance test, you asked the following questions: 1. Consistent with the Schreyer interpretation, should the seat-mounted anchorages of the Glaval bench seat have been loaded sequentially in NHTSA's test? If so, how does NHTSA's test on the Glaval bench seat, where the loads were applied simultaneously, affect NHTSA's tentative conclusion of noncompliance? You are correct that, consistent with the Schreyer interpretation, only floor-mounted anchorages are subject to simultaneous testing under current requirements. However, based on our understanding of the Glaval design, and as discussed below, we consider the anchorages in the Glaval van to be floor-mounted. Therefore, the Schreyer interpretation is not relevant to whether the Glaval van is in compliance with Standard No. 210. Based on photographs included in the Final Report of FMVSS 210 Compliance Testing of 1991 Glaval Van (Report No. 210-GTL-91-003), it appears that the seat belts are attached to a bar which runs along the floor behind the bench seat. The bar is directly mounted to floor brackets which run along each side of the seat. Section S4.2 of Standard No. 210 specifies that floor-mounted seat belt anchorages for adjacent designated seating positions are simultaneously tested. The term 'seat belt anchorage' is defined in section S3 as 'the provision for transferring seat belt assembly loads to the vehicle structure.' In the design at issue, the seat belt anchorage, or provision for transferring seat belt assembly loads to the vehicle structure, includes the seat belt bar. Since the seat belt bar is mounted to the floor by means of the two brackets along the sides of the seat, the seat belt anchorage is 'floor-mounted.' I note for your information that, on April 30, 1990, the agency published a final rule amending Standard No. 210 to, among other things, require simultaneous loading of all anchorages common to the same occupant seat. This amendment is effective on September 1, 1992. 2. Since Standard 207 requires simultaneous loading of the forces required by Standard 207 along with those required by Standard 210, does the Schreyer interpretation mean that, for a bench seat with seat-mounted anchorages, the proper loading for a test pursuant to FMVSS 207 should be 20 times the seat weight plus the proper load for one designated seating position on the bench seat? Your understanding of the Standard No. 207 test is correct. I hope you find this information helpful. If you have further questions, please contact Mary Versailles of my staff at this address or by telephone at (202) 366-2992. Sincerely, Paul Jackson Rice Chief Counsel "; |
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ID: aiam5625OpenMr. Robert R. Brester Director of Product Engineering Velvac Inc. 2900 South 160th Street New Berlin, WI 53151; Mr. Robert R. Brester Director of Product Engineering Velvac Inc. 2900 South 160th Street New Berlin WI 53151; "Dear Mr. Brester: This responds to your request for an interpretatio concerning how Standard No. 105, Hydraulic Brake Systems, affects the brake products you sell. According to your letter: Velvac Inc. manufactures and sells brake components and power braking systems for trailers and truck tag axles. These brake systems are not part of the primary vehicle braking system. In the case of a tag axle, our customers are retrofitting a standard vehicle with an additional axle to increase its load carrying capacity. In the case of a trailer, our system may be the only source of braking. The brake components Velvac supplies generally include control valving, brake boosters and various types of hoses and fittings. These items can be sold both as components and as complete power brake kits. (See attached catalogue drawings . . . .) You stated that Mr. Richard Carter of this agency advised you that different combinations of braking components may be used to achieve the braking performance requirements of Standard No. 105, and that the responsibility of certifying vehicles to Standard No. 105 lies in the hands of your customers. This information is correct. However, you should be aware that some of the components listed in your catalogue are covered by Standard No. 106, Brake Hoses, and must be certified by their manufacturer as complying with that standard. A further discussion of the issues raised by your letter is provided below. By way of background information, the National Highway Traffic Safety Administration (NHTSA) is authorized to issue Federal motor vehicle safety standards for new motor vehicles and new motor vehicle equipment. NHTSA has exercised this authority to issue several vehicle and/or equipment standards related to braking performance. These standards include the aforementioned Standards No. 105 and No. 106, as well as ones on air brake systems, motorcycle brake systems, and motor vehicle brake fluids. You specifically asked about Standard No. 105. That standard specifies requirements for hydraulic service brake and associated parking brake systems, and applies to passenger cars, multipurpose passenger vehicles, trucks, and buses with hydraulic service brake systems. If your brake products are installed as original equipment on a new vehicle subject to Standard No. 105, the vehicle manufacturer is required to certify that, with the products installed, the vehicle satisfies the requirements of that standard (as well as all other applicable safety standards). If your brake products are added to a previously certified new motor vehicle prior to its first sale, the person who modifies the vehicle would be an 'alterer' under our regulations, and would be required to certify that, as altered, the vehicle continues to comply with all of the safety standards affected by the alteration. If your products are installed on a used vehicle by a business such as a repair shop, the repair shop would not be required to attach a certification label. However, it would have to make sure that it did not knowingly make inoperative any part of a device or element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with an applicable safety standard, such as the hydraulic brake system. Assuming you do not manufacture or alter new vehicles, you do not have a responsibility to certify a vehicle's compliance with Standard No. 105. However, I note that some of the brake products listed in your catalogue are covered by Standard No. 106. That standard specifies requirements for motor vehicle brake hose, end fittings and assemblies. Standard No. 106 applies not only to new vehicles, as is the case with Standard No. 105, but also to brake hoses, end fittings and assemblies that are sold individually or in kit form. Manufacturers of these items must certify that the equipment complies with Standard No. 106, and persons selling these items must sell only certified items. NHTSA also has the authority to investigate safety-related defects. Manufacturers of motor vehicles and items of motor vehicle equipment are subject to statutory requirements concerning the recall and remedy of products with defects related to motor vehicle safety. If a manufacturer or NHTSA determines that a safety-related defect exists, the manufacturer must notify purchasers of its product and remedy the problem free of charge. (This responsibility is borne by the vehicle manufacturer in cases in which your products are installed on a new vehicle by or with the express authorization of that vehicle manufacturer.) Any manufacturer that fails to provide notification of or remedy for a defect may be subject to a civil penalty of up to $1,000 per violation. I have enclosed an information sheet that briefly describes various responsibilities of motor vehicle manufacturers under our regulations, and information on how you can obtain copies of our standards. I hope this information is helpful. If you have any further questions, please call Edward Glancy of my staff at (202) 366-2992. Sincerely, John Womack Acting Chief Counsel Enclosure"; |
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ID: aiam0077OpenChester G. Parsons, President, Elgin Sweeper Company, 1300 West Bartlett Road, Elgin, IL 60120; Chester G. Parsons President Elgin Sweeper Company 1300 West Bartlett Road Elgin IL 60120; Dear Mr. Parsons: This is in response to your letter of April 17 requesting eithe confirmation of your opinion that it was 'not the intent of the Federal Motor Vehicle Safety Standards to apply to 'the three wheeled motor street sweeper manufactured by Elgin, or, in the alternative, consideration by the Federal Highway Administration of the establishment of a separate classification for these vehicles.; Three wheeled motor street sweepers are 'motor vehicles' within th meaning of the National Traffic and Motor Vehicle Safety Act of 1966. However, they do not fall into any of the vehicle types defined thus far, to which standards are applicable, and consequently there are no standards applicable to it at this time.; Sincerely, William Haddon, Jr., M.D., Director |
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ID: aiam5275OpenMs. Amantha L. Barbee Sales Coordinator Thomas Built Buses, Inc. Post Office Box 2450 High Point, NC 27261; Ms. Amantha L. Barbee Sales Coordinator Thomas Built Buses Inc. Post Office Box 2450 High Point NC 27261; "Dear Ms. Barbee: This responds to your letter to me of October 14 1993, and your telephone conversation with Walter Myers of my staff on October 22, 1993. You stated in your letter that you are the Head Start Sales Coordinator for Thomas Built Buses, Inc., and in that capacity you have found that many Head Start agencies are using conventional vans to transport Head Start students to and from their programs. You stated that when you asked the directors of the agencies why they did not use vehicles that comply with Federal motor vehicle safety standards (FMVSS) for school buses, their usual answer was 'because we have not been told otherwise.' You then asked whether this practice is illegal and if so, what your organization can do to rectify the situation. As Mr. Myers explained in your telephone conversation, this agency has repeatedly stated that Head Start facilities are preprimary schools. Therefore, new buses sold to Head Start centers for use in transporting Head Start participants to and from school must comply with all Federal motor vehicle safety standards applicable to school buses. However, Federal law does not require Head Start facilities to use complying school buses or any other particular vehicles. The individual states, not the Federal government, have authority over the use of vehicles. As promised by Mr. Myers, please find enclosed interpretation letters previously issued by us on this issue, as follows: to Hon. Paul David Wellstone, U.S. Senate, dated Jan. 26, 1993, to Mr. Chuck Anderson, dated Aug. 21, 1992, and to Mr. Charles Pekow, dated Sept. 27, 1985. I hope this information will be useful. If you have any further questions or desire any further information, please feel free to contact Mr. Myers at this address or at (202) 366-2992. Sincerely, John Womack Acting Chief Counsel Enclosures "; |
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ID: aiam3572OpenMr. Jeff Wimer, P.O. Box 152, Auburn, IN 46706; Mr. Jeff Wimer P.O. Box 152 Auburn IN 46706; Dear Mr. Wimer: This responds to your phone request of June 11, 1982, concernin Federal motor vehicle safety standards that apply to motorcycle sidecars sold as aftermarket motor vehicle equipment.; While there are no 'sidecar' standards, certain of the items o equipment that may be found in sidecars are covered by Federal equipment safety standards. Specifically, brake hoses, lighting equipment, tires, rims, and glazing materials (if provided) would have to comply with Standards Nos. 106, 108, 119, 120 and 205. I have enclosed an information sheet explaining how you can obtain copies of the agency's safety standards.; Because a sidecar itself is an item of motor vehicle equipment, th manufacturer of any sidecar sold in the aftermarket would be responsible for notification and remedy in the event the product was determined to contain a safety-related defect.; If you have any further questions, please let me know. Sincerely, Frank Berndt, 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.