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: aiam3200OpenMr. J. Kawano, General Manager, U.S. Representative Office, Toyota Motor Co., Ltd., One Harmon Plaza, Secaucus, NJ 07094; Mr. J. Kawano General Manager U.S. Representative Office Toyota Motor Co. Ltd. One Harmon Plaza Secaucus NJ 07094; Dear Mr. Kawano: This responds to your recent letter asking whether a manual, Type 1 la belt assembly installed in conjunction with an upper torso automatic belt can qualify as the pelvic portion of a Type 2 belt assembly for purposes of the elongation requirements of Safety Standard No. 209, *Seat Belt Assemblies*.; Safety Standard No. 209 limits the elongation of webbing in a Type lap belt to 20 percent, but allows the webbing in the pelvic portion of a Type 2 belt assembly to elongate 30 percent. The standard defines a 'type 2 seat belt assembly' as a combination of pelvic and upper torso restraints. Although a manual lap belt installed in conjunction with an automatic upper torso belt is not in fact a 'combination' belt as originally contemplated by the definition, the function of the system is equivalent to the Type 2 belt. Therefore, since the pelvic portion of a Type 2 belt may elongate up to 30 percent under the requirements of the standard, we conclude that a lap belt installed in conjunction with an upper torso automatic belt should be considered the pelvic portion of a Type 2 system and subject to the same requirement.; To assure that all interested persons are aware of this interpretation the agency intends to amend Safety Standard No. 209 to clarify that manual lap belts installed in conjunction with automatic upper torso belts may meet the elongation requirements specified for Type 2 belts. The amendment will also specify that such lap belts must be labeled to indicate they are only intended for use with an automatic upper torso restraint. Rulemaking in this regard will be initiated in the near future.; Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam4896OpenMr. Ken Hanna Lectric Limited, Inc. 7322 S. Archer Road Justice, Illinois 60458; Mr. Ken Hanna Lectric Limited Inc. 7322 S. Archer Road Justice Illinois 60458; Dear Mr. Hanna: This responds to your letter of July 8, 1991, t Richard Van Iderstine of this agency. You asked whether a proposed manufacturing and marketing scheme would be in violation of any NHTSA regulations. You intend to petition for rulemaking to amend Standard No. 108 to reinstate SAE Standard J579a as an optional standard for sealed beam headlamps. These lamps would be used on 'antique cars.' Until SAE J579a is reinstated, you would like to manufacture headlamps to conform to SAE J579c, the current specification for sealed beam headlamps that is incorporated into Standard No. 108. However, you do not wish to mark the lenses with the identification nomenclature that SAE J579c requires (presumably because it was lacking from the J579a headlamps with which the antique cars were originally equipped). You ask if you may market these lamps with identification on the package stating that they are 'for display purposes only and not approved for highway use.' Your letter clearly indicates that the purpose of manufacturing the sealed beam headlamps is for their installation on motor vehicles, albeit old ones, and not for 'display purposes only.' The headlamps are motor vehicle equipment, and must comply with all applicable Federal motor vehicle safety standards, in this instance, SAE J579c. Partial compliance with the requirements is not permissible, and the lenses of headlamps manufactured to conform with SAE J579c must be marked as that standard requires. Thus, your suggested manufacturing and marketing scheme would not conform to Standard No. 108, and, if pursued, it would be a violation of the National Traffic and Motor Vehicle Safety Act. The manufacture and sale of noncomplying motor vehicle equipment is a violation of the for which a civil penalty of up to $1,000 per violation may be imposed, up to a total of $800,000 for any related series of violations. In addition, as the manufacturer of the equipment, Lectric Limited must certify them as meeting all applicable Federal motor vehicle safety standards, and similar penalties may be imposed for certification that is false and misleading in a material respect. Finally, the manufacturer of nonconforming equipment is required to notify and remedy in accordance with the requirements of the Act. Because SAE J579a and 579c headlamps are identical in external appearance except for lens marking, we do not believe that authenticity of the appearance of older vehicles will be affected to any discernable degree by requiring that their lenses be marked as the contemporary standard requires. Sincerely, Paul Jackson Rice Chief Counsel; |
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ID: aiam2041OpenMr. James H. Whitaker, Associate Professor, The University of Connecticut, Storrs, CT 06268; Mr. James H. Whitaker Associate Professor The University of Connecticut Storrs CT 06268; Dear Mr. Whitaker: Please forgive the delay in responding to your letter of May 22, 1975 which inquired about the status of tire grading standards.; On May 20, 1975, the National Highway Traffic Safety Administratio issued the Uniform Tire Quality Grading Standards with a series of effective dates beginning January 1, 1976 (40 FR 23073, May 28, 1975). On July 3, 1975, the regulation was republished with minor changes (40 FR 28071). On August 14, 1975, a stay of the effective dates was granted by the United States Court of Appeals for the Sixth Circuit, pending review of the validity of the regulation in a suit brought by eight tire manufacturers.; For your convenience, I have enclosed copies of the Federal Registe notices referred to above.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam0586OpenMr. Irving Frank, Frank and Frank, Counselors at Law, 11 Park Place, New York, New York 10007; Mr. Irving Frank Frank and Frank Counselors at Law 11 Park Place New York New York 10007; Dear Mr. Frank: Thank you for your letter of December 22, 1971, in which you requeste safety information pertaining to 1964 Chevrolet hood latching mechanisms.; Our Offices of Defects Investigation and Accident Investigation an Data Analysis have made a search of their files, and have found no specific information relating to defects in 1964 Chevrolet hood latching. I should like to point out that, inasmuch as Federal motor vehicle safety standards first became effective on January 1, 1968, we have not in all cases received information pertaining to defects which may have affected earlier vehicles. We have, however, monitored a recall campaign affecting potentially defective hood latch mechanisms on 1969 Mercury Cougars, wherein the possibility of binding components could cause the hood to open while the vehicle is in motion. In this connection, we are enclosing a copy of a report, *Motor Vehicle Safety Defect Recall Campaigns*, covering calendar year 1969. Your attention is invited to page 13 of the report for a brief summary of the action, and to page 1 for instructions for obtaining further detailed information relative to this campaign. We are, of course, continuing to be alert for further problems in this area.; Regarding designs of hood latch systems, we favor the type system yo describe in which two complete operations are necessary before the hood can be opened completely. I am enclosing a copy of Federal Motor Vehicles Safety Standard No. 113, entitled Hood Latch Systems, which has required secondary latch positions or secondary hood latch systems on most vehicles since January 1, 1969.; Thank you for your inquiry. Do not hesitate to contact me if I can b of further assistance.; Sincerely, Robert L. Carter, Acting Associate Administrator, Moto Vehicle Programs; |
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ID: aiam2411OpenMr. Byron A. Crampton, Manager of Engineering Services, Truck Body and Equipment Association, Inc., 5530 Wisconsin Avenue, Suite 1220, Washington, DC 20015; Mr. Byron A. Crampton Manager of Engineering Services Truck Body and Equipment Association Inc. 5530 Wisconsin Avenue Suite 1220 Washington DC 20015; Dear Mr. Crampton: This responds to the Truck Body and Equipment Association's letter o September 14, 1976, inquiring as to the effect of Standard No. 121, *Air Brake Systems*, on State laws relating to air brake performance. You ask whether the Commonwealth of Massachusetts can impose requirements pertaining to parking brake release on trucks and buses which differ from provisions contained in the Federal standard.; I believe that the question you raised is identical to a questio raised by the State of California, International Harvester Company, and White Motor Corporation in October 1974, prior to the effective dates of Standard No. 121. It was our opinion at that time that promulgation by a State of a more restrictive parking brake requirement providing for the installation of a release not specified in Standard No. 121 was prohibited by S 103(d) of the National Traffic and Motor Vehicle Safety Act. A copy of that letter is enclosed for your information.; Sincerely, Frank A. Berndt, Acting Chief Counsel |
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ID: aiam3129OpenMr. H.A. Ritzenthaler, VDO-ARGO Instruments Inc., 980 Brooke Road, P.O. Box 2630, Winchester, Virginia 22601; Mr. H.A. Ritzenthaler VDO-ARGO Instruments Inc. 980 Brooke Road P.O. Box 2630 Winchester Virginia 22601; Dear Mr. Ritzenthaler: This is in response to your letter of January 25, 1979, in which yo stated your interpretation of Federal Motor Vehicle Safety Standard 127, *Speedometers and Odometers*, and asked that we advise you if action taken in accordance with this interpretation would place your company in violation of the standard. This letter is to confirm that your interpretation is correct.; According to your interpretation of Safety Standard 127, thos provisions which become effective for new motor vehicles on September 1, 1979 and September 1, 1980 are not applicable to speedometers and replacement parts produced for use in motor vehicles manufactured before those dates. This is correct because Safety Standard 127 is a vehicle standard and an equipment standard which applies to passenger cars, multipurpose passenger vehicles, trucks, motorcycles, and buses manufactured after the standard's effective dates and to speedometer and odometers for use in such vehicles. (Section 3, Safety Standard 127).; Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam1114OpenMr. F.A. Stewart, Vice President, Safety & Reliability, AM General Corporation, Wayne, MI 48184; Mr. F.A. Stewart Vice President Safety & Reliability AM General Corporation Wayne MI 48184; Dear Mr. Stewart: This is in reply to your letter of March 22, 1973, concerning th conformity of buses manufactured by AM General Corporation with paragraph S5.1.1 of Standard No. 217, Bus Window Retention and Release.' Your letter states, enclosing a drawing, that the side sash construction in these buses includes an aluminum tie bar that connects the upper and lower portion of the sash, and is located on the inside and at the center of the glass. You state this configuration precludes testing as specified in S 5.1.1, which specifies that the head form applying the load be placed at the center of the glazing. You request that the standard be revised to permit testing with the head form located as close as possible to the center of the glazing.; Based on the information you have provided, we are of the opinion tha the configuration of this window should be treated under paragraph S5.1 as two separate windows, even though only one sheet of window glazing is used. The tie bar appears to be an integral part of the window sash, and by preventing an occupant from contacting the window at that point, performs essentially the same function as a conventional divider strip. Consequently, we would expect to test this window configuration by applying the head form to the center of each half of the glazing surface.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam4316OpenMr. Barry Bartlett, President, Canadian Automotive Radiator, Air Industrial Park, P. O. Box 189, Debert, Nova Scotia, BOM 1GO, CANADA; Mr. Barry Bartlett President Canadian Automotive Radiator Air Industrial Park P. O. Box 189 Debert Nova Scotia BOM 1GO CANADA; Dear Mr. Barlett(sic): Thank you for your letter of May 5, 1987, concerning Standard No. 301 *Fuel System Integrity*. You asked the agency to confirm that the requirements set out in the standard apply only to fuel systems installed as items of original equipment in new vehicles and do not apply to aftermarket fuel systems. Several of the Federal Motor Vehicle Safety Standards apply both to original and aftermarket equipment. Standard No. 301, however, applies only to fuel systems installed as items of original equipment in new vehicles.; Although the agency does not have any standards that directly apply t aftermarket fuel systems, manufacturers of motor vehicle equipment, which includes aftermarket fuel systems, are subject to the requirements in section 151-159 of the Vehicle Safety Act concerning the recall and remedy of products with defects related to motor vehicle safety. I have enclosed an information sheet which briefly describes those responsibilities.; In addition, installation of your product can be affected by sectio 108(a)(2)(A) of the National Traffic and Motor Vehicle Safety Act. That section prohibits commercial businesses from knowingly rendering inoperative devices or elements of design installed in a vehicle in compliance with the Federal motor vehicle safety standards. Thus, a manufacturer, dealer, distributor or motor vehicle repair shop that installs replacement fuel tanks must ensure that it does not knowingly render inoperative the vehicle's compliance with Standard No. 301.; The prohibition of Section 108(a)(2)(A) does not apply to individua vehicle owner who alter their own vehicles. Thus, under Federal law, they may install or remove any items of motor vehicle equipment regardless of its effect on compliance with Federal motor vehicle safety standards. However, the agency encourages vehicle owners not to remove or otherwise tamper with vehicle safety equipment.; If you have any further questions , please let me know. Sincerely, Erika Z. Jones, Chief Counsel |
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ID: aiam3579OpenMr. John I. Kitchen, President, Tri-City Tires, Inc., 1016 Butt Street, Chesapeake, VA 23324; Mr. John I. Kitchen President Tri-City Tires Inc. 1016 Butt Street Chesapeake VA 23324; Dear Mr. Kitchen: This responds to your recent letter to Mr. Kratzke of my staff askin for a clarification of the requirements of Federal Motor Vehicle Safety Standard No. 120 (49 CFR S571.120) concerning the use of retreaded tires on new trucks and trailers. Specifically, you wanted to know whether a DOT symbol was required to appear on any retreaded tires so used.; Pursuant to your request in a telephone conversation with Mr. Kratzke he sent you a copy of a March 22, 1978 letter from this agency to Dorsey Trailers. That letter stated that retreaded tires could be used on new trucks and trailers, and that retreaded tires used for that purpose are not required to have a DOT symbol. This conclusion is mandated by the requirement in 49 CFR S574.5 that 'the DOT symbol shall not appear on tires to which no Federal Motor Vehicle Standard is applicable.' Since no safety standard applies to retreaded tires for use on trucks and trailers, it follows that the DOT symbol must not appear on those tires.; In your recent letter, you enclosed a copy of a September 29, 198 letter from this agency to Elgene Tire Company. That letter states that, for purposes of Standard No. 120, used tires are interpreted to include retreaded tires. As you noted in your phone conversation with Mr. Kratzke, an implication of this interpretation seems to be that retreaded tires are required, as used tires, to have a DOT symbol.; The agency position regarding the presence of the DOT symbol o retreaded tires has been consistent since 1978, i.e., that the controlling provision on that issue is S574.5 and therefore the DOT symbol is not required to appear on retreaded truck tires, and, indeed, must not appear on those tires. Retreaded truck tires without the DOT symbol may be used on new trucks and trailers in full compliance with Standard No. 120. To clarify this point, the agency published a proposal on October 30, 1980 (45 FR 71834) to amend Standard 120 so that it expressly permits the installation of retreaded tires on new trucks and trailers. (A copy of the proposal is enclosed) Final action on that proposal is expected this summer.; I trust that this response clears up the confusion to which you allude in your letter regarding these requirements. Should you have any further questions in this area, feel free to contact Mr. Kratzke at (202) 426-2992.; Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam1544OpenMr. Kevin J. Adams, Director, Department of Parking & Transit Facilities, University of Virginia, 408 Brandon Avenue, Charlottesville, VA 22903; Mr. Kevin J. Adams Director Department of Parking & Transit Facilities University of Virginia 408 Brandon Avenue Charlottesville VA 22903; Dear Mr. Adams: This is in reply to your letter of May 28, 1974, asking whether ther are any Federal laws that would have a bearing on the University of Virginia's contemplated decision to purchase a tire grooving machine to regroove tires that will be used on buses operated by the University.; The NHTSA has recently amended Federal 'Regrooved Tire' regulations (4 CFR 569, copy enclosed) to prohibit any person from regrooving his own tires (49 CFR S 569.7). The regulation would apply to the University with respect to the tires you contemplate regrooving for use on university buses, and should certainly bear on your decision to purchase a tire regrooving machine.; The amendment to the regulation resulted from litigation *(Nationa Association of Motor Vus Owners* v. *Brinegar*, 483 F.2d 1294 (D.C. Cir. 1973)) in which the United States Court of Appeals held that under section 204 of the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1524) Congress authorized this agency to permit only the sale of regrooved tires.; There are presently some efforts being made in the Congress to amen the Safety Act to alter the effect of this court deicsion. No final action of any kind has been taken, however, and we do not know whether or when such action might be taken.; Sincerely, Lawrence R. Schneider, 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.