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: aiam0324OpenLawrence D. Heitsch, Darden, Neef & Heitsch, Attorneys and Counselors, 3066 Penobscot Building, Detroit, MI 48226; Lawrence D. Heitsch Darden Neef & Heitsch Attorneys and Counselors 3066 Penobscot Building Detroit MI 48226; Dear Mr. Heitsch: This is in response to your letter of January 20, 1971, petitioning fo rulemaking pursuant to 49 CFR 553.31, asking that the Tire Identification and Record Keeping Regulation be inapplicable to mobile homes. The points raised in your petition have been thoroughly considered, however, your petition, by copy of this letter, is denied. As you know, many of the points you raised were considered in connection with the interpretation of 'Motor Vehicle' as it refers to trailers, issued March 31, 1970 (35 F.R. 5333) (Copy Enclosed). The interpretation concluded that a mobile home is a motor vehicle within the meaning of the National Traffic and Motor Vehicle Safety Act of 1966, (15 U.S.C. 1381 *et seq*.). As such, mobile home manufacturers are required to comply with the requirements of Part 574,(sic); The burden placed on the mobile home manufacturer by the regulatio does notaappear (sic) unreasonable. The regulation requires that the vehicle manufacturer or his designee maintain a record of the tires shipped on or in its vehicles and maintain the names and addresses of the purchasers of its vehicles. Locating the purchaser should be a comparatively easy task.; Mobile homes are constructed with a view, of course, to thei over-the-road capabilities. The Tire Identification and Record Keeping Regulation should be applicable to mobile homes since it relates directly to one of the instrumentalities for moving a mobile home. Should a tire sold with a mobile home be defective, we consider it essential that the purchaser of the vehicle be notified of this fact.; Sincerely, Lawrence R. Schneider, Acting Chief Counsel |
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ID: aiam2319OpenMr. G. Buzzi-Ferraris, Technical Manager, Pirelli Tire Corporation, 600 Third Avenue, New York, New York 10016; Mr. G. Buzzi-Ferraris Technical Manager Pirelli Tire Corporation 600 Third Avenue New York New York 10016; Dear Mr. Buzzi-Ferraris: I am writing in response to your March 12, 1976, letter to Mr. Rober Aubuchon of this agency, concerning the application of Federal Motor Vehicle Safety Standard No. 119, *New Pneumatic Tires for Vehicles Other than Passenger Cars*, to motor driven cycles whose speed attainable in 1 mile is 30 mph or less.; You have inquired whether such vehicles may be equipped with tires tha --; >>>(i) 'Carry all the inscriptions required by labeling, plus th marking 'MAX SPEED' because speed restricted to less than 55 MPH -- S.6.5.'; (ii) 'Have passed the endurance test -- S.6.1, S.7.2 in accordance wit table III --- speed restricted service: 35 MPH'; (iii) 'have not been tested for high speed S.6.3-- in fact they ar speed restricted ...'<<<; an otherwise comply with the requirements of Standard No. 119. I assume that, where your letter refers to the marking 'MAX SPEED', yo intended 'MAX SPEED 35 MPH'. Although such labeling is not prohibited, the standard does not presently recognize a category of speed-restricted motorcycle tires. Tires for motor driven cycles are subject to the same performance requirements as other motorcycle tires. In particular, the schedule for endurance testing is that found in the 'motorcycle' entry of Table III, rather than the '35 m.p.h.' entry. Similarly, these tires are subject to the high speed performance requirements of S.6.3 without exception. An amendment of Standard No. 119 on this subject is being considered, but no firm decision has been made.; Standard No. 119 prohibits the manufacture of the tires that you hav described on and after March 1, 1975. Standard No. 120, *Tire Selection and Rims for Motor Vehicles Other than Passenger Cars*, prohibits the manufacture of motor-driven cycles equipped with such tires on and after September 1, 1976.; Sincerely, Stephen P. Wood, Assistant Chief Counsel |
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ID: aiam5126OpenChristopher J. Daniels, Esquire Nelson, Mullins, Riley & Scarborough 1330 Lady Street P. O. Box 11070 Columbia, SC 29211; Christopher J. Daniels Esquire Nelson Mullins Riley & Scarborough 1330 Lady Street P. O. Box 11070 Columbia SC 29211; "Dear Mr. Daniels: This responds to your letter to Paul Jackson Rice our former Chief Counsel, in which you referred to a tire manufactured in Canada that had had the 'DOT number' obliterated. Because you think the tire was improperly sold in that condition, you asked whether it was illegal to import a tire from Canada without a DOT number and whether it was illegal to sell or use a tire on the highway without a 'DOT serial number.' By way of background information, under the provisions of the National Traffic and Motor Vehicle Safety Act of 1966, 15 U.S.C. 1381, et seq., as amended (hereinafter Safety Act), the National Highway Traffic Safety Administration is authorized to issue Federal motor vehicle safety standards for new motor vehicles and items of new motor vehicle equipment, the latter of which includes tires. All new motor vehicles and items of new motor vehicle equipment manufactured or imported for sale in the United States must comply with all applicable safety standards. This requirement is found at Section 1397 (a)(1)(A) of the Safety Act which provides 'No person shall . . . import into the United States, any . . . item of motor vehicle equipment manufactured on or after the date any applicable Federal motor vehicle safety standard takes effect . . . unless it is in conformity with such standard . . . .' The effect of that language is to require that tires manufactured on or after the effective date of applicable Federal safety standards must comply with those standards before they can be legally imported into the U.S. Pursuant to Standard 109 (49 CFR 571.109, New Pneumatic Tires) and Standard 119 (49 CFR 571.119, New Pneumatic Tires for Vehicles Other Than Passenger Cars), tire manufacturers must certify compliance therewith by molding the symbol 'DOT' onto the tire sidewalls. Further, 49 CFR 574.5 requires that all tires sold in the U.S. have tire identification numbers (TIN) molded into or onto the tire sidewalls by the manufacturers to facilitate recall in the event of a noncompliance or defect. With that background in mind, your specific questions are answered as follows: 1. Is it illegal to import a tire from Canada without a DOT serial number? Answer: Yes. Each tire imported into the U.S. for highway use must have molded into or onto the sidewall a TIN and a DOT symbol or in the alternative, be accompanied by proof that the tire was manufactured prior to the effective date of applicable safety standards. The only exception to these requirements is that used truck tire casings which have less than 2/32 inch tread remaining and which are being imported solely for retreading prior to on- road use may be imported without displaying the TIN or the DOT symbol. 2. Is it illegal to sell or use a tire for highway use without the DOT serial number? Answer: It is illegal for a manufacturer, distributor, or dealer to sell a new or retreaded tire to the first customer for purposes other than resale without the DOT symbol and the TIN molded into or onto the sidewall. There are no Federal requirements for the use of such tire once it has been sold to the first customer. There may, however, be state safety requirements pertinent to the use of motor vehicle equipment. For that information you should check with appropriate state officials. If the tire in question is intended for or capable of being used on a commercial vehicle, you may want to check also with the Office of Motor Carrier Standards (Room 3404), of the Federal Highway Administration, at this address. (Telephone (202) 366-1790.) I hope this information is helpful. Should you have any further questions, please feel free to contact Walter Myers of this office at (202) 366-2992. Sincerely, John Womack Acting Chief Counsel"; |
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ID: aiam0774OpenMr. Barry G. Taylor, Executive Vice President, Argo Plastic Company, 6830 E. Washington Boulevard, Los Angeles, CA 90040; Mr. Barry G. Taylor Executive Vice President Argo Plastic Company 6830 E. Washington Boulevard Los Angeles CA 90040; Dear Mr. Taylor: This is in reply to your letter of June 27, 1972, requesting Federa 'approval' for plastic glazing material you manufacture. You enclose copies of certificates showing approval by the State of California.; The NHTSA does not provide approvals for glazing materials subject t its requirements. These requirements are found in Federal Motor Vehicle Safety Standard No. 205, 'Glazing Materials,' and apply to glazing materials for use in motor vehicles manufactured for sale in the United States. (This includes the 50 States, the District of Columbia, Puerto Rico, Guam, the Virgin Islands, the Canal Zone, and American Samoa, and not 37 States as you mention.); Under the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 138 *et seq.*) manufacturers must use due care to ensure that products they manufacture conform to applicable standards (15 U.S.C. 1397 (b)(2)). The manufacturer must certify conformity as specified in section 114 of the Act (15 U.S.C. 1403), and in the case of Standard No. 205, as specified in the standard. The NHTSA does not approve manufacturers' products or their certification, but monitors compliance with the standards by purchasing materials on the open market, and testing them to the requirements of the standard. The failure of materials to conform can result in the imposition of civil penalties against the manufacturer, and other sanctions (15 U.S.C. 1398, 1399).; A copy of Standard No. 205 and the National Traffic and Motor Vehicl Safety Act are enclosed for your information.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam2749OpenWilliam Shapiro, P.E., Volvo of America Corporation, Rockleigh, NJ 07647; William Shapiro P.E. Volvo of America Corporation Rockleigh NJ 07647; Dear Mr. Shapiro: This responds to your letter of December 20, 1977, enclosing a previou letter requesting an interpretation of paragraph S4.3(j) of Safety Standard No. 209, *Seat Belt Assemblies*. I am sorry that your earlier letter was misplaced.; Volvo is correct in its interpretation that the requirements fo emergency locking retractors in S4.3(j) (2) and (3) were promulgated for reasons of comfort and convenience, although this in turn is directed toward a safety objective. As you know, the more comfortable and convenient belts are, the more likely they will be worn by motorists. Further, the requirements in these paragraphs assure that the driver can make necessary movements in the occupant compartment safely.; Paragraph S4.3(j) (2) specifies that an emergency locking retractor >>>'shall not lock, if the retractor is sensitive to webbin withdrawal, before the webbing extends 2 inches when the retractor is subjected to an acceleration of 0.3g or less.'<<<; Volvo interprets this to require that the retractor not lock before th webbing extends 2 inches when the *webbing* is subjected to an acceleration of 0.3g. This is incorrect. The requirement specifically states that the *retractor* is to be accelerated. The agency does not agree that keeping the belt stationary and accelerating the retractor is equivalent to keeping the retractor stationary and accelerating the belt. This is due to the fact that inertial forces react upon the retractor during its acceleration that are not present when the webbing alone is accelerated. Therefore, results from the two methods of testing could differ significantly.; I hope this has been responsive to your inquiry, and if we can be o any further assistance please let us know.; Sincerely, Joseph J. Levin, Jr., Chief Counsel |
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ID: aiam1866OpenMr. George E. Talmage, Bowes Seal Fast Corporation, 5902 East Thirty-Fourth Street, Indianapolis, Indiana 46218; Mr. George E. Talmage Bowes Seal Fast Corporation 5902 East Thirty-Fourth Street Indianapolis Indiana 46218; Dear Mr. Talmage: This is in reply to your letter of March 31, 1975, to Mr. Fred Redle of this agency, asking our comments on apparent hardships involved with brake fluid containers and labels that have been obsoleted by the recent deletion of color coding requirements.; Since the deletion leaves Standard no. 116 without mandatory colo requirements, and does not prohibit the use of any color, you may use such cans as you have in hand, or on order, until the effective date of any new color requirements. However, in the interim, this does not preclude any State from specifying or prohibiting fluid and container label color.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam5576OpenDirector of Operations Central New York Regional Transport Authority 200 Cortland Avenue Syracuse, NY 13205; Director of Operations Central New York Regional Transport Authority 200 Cortland Avenue Syracuse NY 13205; Dear Mr. Renock: Mr. M. Judson Brown, the project manager for you Transit Authority's compressed natural gas (CNG) bus project, requested that I explain the Federal regulation of CNG containers to you. According to Mr. Brown's letter, the Central New York Regional Transit Authority believes that certain CNG fuel containers are required to be re-inspected and hydrostatically retested every three years. The short explanation is that this agency, the National Highway Traffic Safety Administration (NHTSA), has no authority to regulate the reinspection or retesting of CNG containers used to fuel motor vehicles, after the first consumer purchase. With regard to Mr. Brown's inquiry into the authority of the Research and Special Programs Administration (RSPA) to require reinspection and retesting, we are forwarding your letter to RSPA so that officials of that agency can explain their regulations to you. NHTSA has been authorized by Congress to issue Federal Motor Vehicle Safety Standards (FMVSSs) for new motor vehicles and new items of motor vehicle equipment. The agency has used this authority to issue FMVSS No. 304, Compressed natural gas fuel container integrity, (49 CFR 571.304) which specifies requirements for the integrity of new CNG containers used to fuel motor vehicles. Each new CNG container manufactured on or after March 27, 1995 (the date the standard took effect) must comply with FMVSS No. 304 and be certified as complying with that standard when it is sold. However, after the first consumer purchase of a motor vehicle or an item of motor vehicle equipment, NHTSA's authority is much more limited and does not extend to the reinspection or retesting of motor vehicles or such equipment. I hope you find this information helpful. If you have any other questions, please contact Marvin Shaw at this address or by phone at (202) 366-2992. Sincerely, John Womack Acting Chief Counsel cc: M. Judson Brown; |
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ID: aiam3271OpenMr. Warren Robbins, Manager, Automobile Division, Sleek-Craft Boats, P.O. Box 3563, Santa Fe Springs, CA 90670; Mr. Warren Robbins Manager Automobile Division Sleek-Craft Boats P.O. Box 3563 Santa Fe Springs CA 90670; Dear Mr. Robbins: This responds to your recent letter requesting an interpretation o Safety Standard No. 214, *Side Door Strength*, as it would apply to a new sports car that your company intends to market. You state that the side doors of this vehicle design can meet the 'intermediate' and 'peak' crush resistance requirements of the standard but not the 'initial' crush resistance requirement because of an outer fiberglass veneer component of the door. You ask whether the vehicle can be exempt from this 'initial' requirement since the door can withstand the maximum forces required by the standard.; The answer to your question is no. Safety Standard No. 214 require doors to comply with all three stages of the crush resistance requirements and there is no provision for an averaging of the crush resistance abilities. Although inboard mounted structures may be effective in preventing intrusion if the door has a large cross section, with a correspondingly large distance between the protective structure and the inner panel, the standard reflects a determination by the agency that doors afford the greatest protection if the crush resistance elements are as close to the outer panel as possible. Additionally, the 'initial' crush resistance requirements are necessary to ensure that the entire door system is structurally sound. This is particularly important because of the risk of occupant ejection if door hinges and latches separated during an accident, allowing the door to fly open.; Although the relief you seek cannot be granted by interpretation o Safety Standard No. 214, there are provisions for temporary exemptions from Safety Standards or portions of safety standards under certain circumstances, such as economic hardship. I am enclosing a copy of the regulation governing temporary exemptions for your information (49 CFR Part 555). After reviewing this regulation, you may wish to petition the agency for a temporary exemption from the 'initial' crush resistance requirements of the standard. The regulation explains the procedures you must follow.; If you have any further questions, please contact Hugh Oates of m office at 202-426- 2992.; Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam2899OpenMr. Robert B. Kurre, Wayne Corporation, P. O. Box 1447, Industries Road, Richmond, IN 47374; Mr. Robert B. Kurre Wayne Corporation P. O. Box 1447 Industries Road Richmond IN 47374; Dear Mr. Kurre: This responds to your September 6, 1978, letter asking for clarification of the requirements of Standard No. 217, *Bus Window Retention and Release*. In particular you ask whether paragraph S5.3.3 which requires that, 'a continuous warning sound shall be audible at the driver's seating position and in the vicinity of the emergency exit door having the unclosed mechanism' means that there must be a separate warning alarm at each emergency door and a warning alarm in the driver's seating area.; In your letter you recite the early history of this standard whic addresses the alarm system requirement. At the time of the final rule's adoption, commenters questioned the requirement in the same manner that you have questioned it in your letter. The agency stated in the preamble to the final rule (41 FR 3871) that the requirement mandated the use of audible alarms at each door and in the driver's seating location. The rationale for that requirement was outlined in the preamble and referenced in your letter. Since this interpretation of paragraph S5.3.3 was part of the initial rulemaking with respect to this standard, it is not necessary for the agency to undertake further rulemaking at this time to make this requirement binding upon manufacturers. The multiple alarm system requirement has been the agency's interpretation of paragraph S5.3.3 since its issuance, and manufacturers are required to comply with the safety standards as they are interpreted by the agency.; Sincerely, Joseph J. Levin, Jr., Chief Counsel |
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ID: aiam2933OpenLori Malinovsky, Gladiator Southeast, 1250 8th Street, Jacksonville, FL 32205; Lori Malinovsky Gladiator Southeast 1250 8th Street Jacksonville FL 32205; Dear Ms. Malinovsky: This is in response to your letter of October 30, 1978, requestin information on the Federal Odometer Mileage Statement. Section 580.5(b) of Title 49 Code of Federal Regulations provides; >>>A transferor of a new vehicle prior to its first transfer fo purposes other than resale need not disclose the vehicle's odometer mileage.<<<; Manufacturers of vehicles fall within this section and are exempt fro the disclosure requirements because they sell vehicles to dealers who intend only to resell the vehicles. Since Gladiator, Inc. purchased the vans new with the intent to resell them and since the vans are being sold to dealers only who also intend only to resell them, Gladiator is likewise exempt from the disclosure requirements. The dealerships, however, will be selling the vans to customers who will use them for some purpose other than resale. Consequently, the dealerships are required to issue disclosure statements each time they sell a van.; Sincerely, John Womack, Assistant 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.