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 |
|---|---|
ID: aiam2506OpenMr. Karl-Heinz Ziwica, Manager, Safety Engineering, BMW of North America, Inc., Montvale, New Jersey 07645; Mr. Karl-Heinz Ziwica Manager Safety Engineering BMW of North America Inc. Montvale New Jersey 07645; Dear Mr. Ziwica: This is in response to your January 17, 1977, letter concerning th requirements of Safety Standard No. 111, *Rearview Mirrors*, For passenger cars. You requested confirmation of your interpretation that the standard specifies no requirements for outside rearview mirrors on the passenger's side of the vehicle when the inside rearview mirror meets S5.1.1 of the standard.; Your interpretation is correct. If the inside rearview mirror of passenger car meets the specified performance requirements, the vehicle is not required to be equipped with an outside rearview mirror on the passenger's side. However, a manufacturer is free to equip its vehicles with outside right-hand mirrors, either plane or convex, if he choses(sic).; You should note that each passenger car whose inside rearview mirro does not meet the field of view performance requirements of Paragraph S5.1.1 must have an outside rearview mirror of unit magnification installed on the passenger's side of the vehicle.; Sincerely, Frank Berndt, Acting Chief Counsel |
|
ID: aiam3007OpenMr. Marvin Manes, Oestreicher, Sternberg & Manes, Suite 402, Wolf Ledges Professional Bldg., 411 Wolf Ledges Parkway, Akron, OH 44311; Mr. Marvin Manes Oestreicher Sternberg & Manes Suite 402 Wolf Ledges Professional Bldg. 411 Wolf Ledges Parkway Akron OH 44311; Dear Mr. Manes: This is in response to your letter of March 13, 1979, asking whethe your client, a tire brand name owner, is permitted to bill its dealers and distributors directly for the costs of supplying Uniform Tire Quality Grading (UTQG) information pursuant to 49 CFR 575.104 and maintaining records of tire sales pursuant to 49 CFR 574.7.; The UTQG regulation requires that tire manufacturers and brand nam owners 'provide' grading information for each of their tires (49 CFR 575.104(d)(1)(i)). Similarly, the Tire Identification and Record Keeping regulation requires these parties to 'provide' upon request tire registration forms to dealers and distributors (49 CFR 575.7(a)) and directs tire manufacturers and brand name owners to maintain or have maintained for them records of the information acquired on these registration forms (49 CFR 574.7(b)).; A billing arrangement of the type your client suggests would in effec make the tire manufacturer or brand name owner the agent of the dealer or distributor for purposes of grading and registering tires. Such a practice would run counter to the intention of the agency that manufacturers and brand name owners bear primary responsibility for implementation of tire grading and registration. The National Highway Traffic Safety Administration (NHTSA) will take whatever action is necessary, including possible revision of the regulations, to prevent manipulation of the tire regulations in this manner.; Apart from the legal implications of your client's proposal, NHTS would question the soundness, from a business standpoint, of a plan for direct billing of UTQG and tire recordkeeping costs. Your client's proposed course of action appears to have the aim of generating dissatisfaction with Federal tire regulations among dealers and distributors, and could, by lessening cooperation at the retail level, interfere with your client's ability to fulfill its obligations under the regulations.; Sincerely, Frank Berndt, Acting Chief Counsel |
|
ID: aiam3006OpenMr. Marvin Manes, Oestreicher, Sternberg & Manes, Suite 402, Wolf Ledges Professional Bldg., 411 Wolf Ledges Parkway, Akron, OH 44311; Mr. Marvin Manes Oestreicher Sternberg & Manes Suite 402 Wolf Ledges Professional Bldg. 411 Wolf Ledges Parkway Akron OH 44311; Dear Mr. Manes: This is in response to your letter of March 13, 1979, asking whethe your client, a tire brand name owner, is permitted to bill its dealers and distributors directly for the costs of supplying Uniform Tire Quality Grading (UTQG) information pursuant to 49 CFR 575.104 and maintaining records of tire sales pursuant to 49 CFR 574.7.; The UTQG regulation requires that tire manufacturers and brand nam owners 'provide' grading information for each of their tires (49 CFR 575.104(d)(1)(i)). Similarly, the Tire Identification and Record Keeping regulation requires these parties to 'provide' upon request tire registration forms to dealers and distributors (49 CFR 575.7(a)) and directs tire manufacturers and brand name owners to maintain or have maintained for them records of the information acquired on these registration forms (49 CFR 574.7(b)).; A billing arrangement of the type your client suggests would in effec make the tire manufacturer or brand name owner the agent of the dealer or distributor for purposes of grading and registering tires. Such a practice would run counter to the intention of the agency that manufacturers and brand name owners bear primary responsibility for implementation of tire grading and registration. The National Highway Traffic Safety Administration (NHTSA) will take whatever action is necessary, including possible revision of the regulations, to prevent manipulation of the tire regulations in this manner.; Apart from the legal implications of your client's proposal, NHTS would question the soundness, from a business standpoint, of a plan for direct billing of UTQG and tire recordkeeping costs. Your client's proposed course of action appears to have the aim of generating dissatisfaction with Federal tire regulations among dealers and distributors, and could, by lessening cooperation at the retail level, interfere with your client's ability to fulfill its obligations under the regulations.; Sincerely, Frank Berndt, Acting Chief Counsel |
|
ID: aiam1818OpenHonorable J. Glenn Beall, Jr., United States Senate, Washington, DC 20510; Honorable J. Glenn Beall Jr. United States Senate Washington DC 20510; Dear Senator Beall: I would like to respond to your February 20, 1975, request fo consideration of Mr. R. L. Herman's views on Standard No. 121, *Air brake systems*. Mr. Herman objects that the National Highway Traffic Safety Administration (NHTSA) may have ignored the majority of comments submitted in response to its recent proposal to delay implementation of the standard, that implementation of the standard should be reconsidered by an activity other than the NHTSA, and that the new brake systems may be less safe than existing systems.; Standard No. 121 was issued as a final rule in February 1971. The NHTS realized that the economic situation in the automotive industry this past fall might justify a postponement of the scheduled January 1, 1975, effective date. In the short time available for review of the standard before its effective dates, the NHTSA issued a proposal, received comments, and made its decision.; The NHTSA concluded that net economic benefit would not be derived fro postponement. The decision was based on evaluation of all the comments, including those concerning the standard's immediate short-term impact on the national economic picture. An important factor in this case was the imminence of the standard and the degree to which financial and employment commitments were made.; As you may know, the President has directed (by Executive Order 11821 that each Federal agency consider the inflation impact of its regulatory actions. At the time of the NHTSA decision on December 31, 1974, final criteria and procedures for implementation of the Order were not yet established. The NHTSA did, however, analyze economic effects of its proposal. The NHTSA has publicly committed itself to continue monitoring the effectiveness of its standard in accordance with its statutory mandate and the President's direction, with a view to identifying any modifications that would lower costs while achieving comparable levels of safety.; An independent evaluation of the standard and its implementation by th Office of the Secretary (of the Department) was recently conducted, and this study supports the NHTSA decision. A copy of a letter regarding that evaluation is enclosed, and it discusses in detail Mr. Herman's concern about the field testing of the new braking components.; Thank you for your interest in motor vehicle safety. Sincerely, James C. Schultz, Chief Counsel |
|
ID: aiam1985OpenMr. Warren M. Heath, Commander, Engineering Section, Department of California Highway Patrol, P. O. Box 898, Sacramento, CA 95804; Mr. Warren M. Heath Commander Engineering Section Department of California Highway Patrol P. O. Box 898 Sacramento CA 95804; Dear Mr. Heath: This is in response to your letter dated April 2, 1975, in which yo ask several questions regarding test procedures for Federal Motor Vehicle Safety Standard No. 218, *Motorcycle Helmets*.; We are not aware of any inconsistency between Standard No. 218 and th compliance procedures that our Office of Standards Enforcement has developed in connection with it. If there were any, of course, the standard would be controlling. The standard specifies a drop height, and a 'guided free fall' from that height. We consider 'free fall' to be an objective and unambiguous physical term, meaning a movement in response to the force of gravity unimpeded by any resistance except air resistance. The requirement the equipment must be capable of meeting, therefore, refers to a fall in which the guiding method imparts no significant resistance, *i.e.*, it does not affect the results. Although in practice a perfectly frictionless guided fall may be unachievable, a manufacturer must ensure that his product would meet the requirement no matter how small the friction. An analogy is the fixed collision barrier defined in S 49 CFR 571.3, which requires a vehicle to meet a barrier crash test requirement using a barrier that absorbs no significant part of the vehicle's energy. Helmet manufacturers must assume, therefore, that the government will test their products using test fixtures that impart as little friction to the fall as possible. We therefore consider the issue of what systems were 'in general use at the time ANS Z90.1 and FMVSS 218 were written' to be irrelevant to the question of compliance.; This discussion should answer your first two questions. We do no accord any legal status to 'old' test procedures as opposed to 'new' ones. With regard to the question about correlation studies, we have not conducted any and I know of no plans to do so. Finally, Standard 218 presently covers only size C helmets because drawings and headforms for the other sizes are not yet available. Therefore, no formal compliance testing can be done on other sizes of helmets. We hope soon to publish drawings and make available models of size A, B and D headforms, at which time a date will be set for extending Standard 218 to these other sizes. Your continuing interest in motorcycle safety is greatly appreciated.; Sincerely, Frank Berndt, Acting Chief Counsel |
|
ID: aiam1986OpenMr. Warren M. Heath, Commander, Engineering Section, Department of California Highway Patrol, P. O. Box 898, Sacramento, CA 95804; Mr. Warren M. Heath Commander Engineering Section Department of California Highway Patrol P. O. Box 898 Sacramento CA 95804; Dear Mr. Heath: This is in response to your letter dated April 2, 1975, in which yo ask several questions regarding test procedures for Federal Motor Vehicle Safety Standard No. 218, *Motorcycle Helmets*.; We are not aware of any inconsistency between Standard No. 218 and th compliance procedures that our Office of Standards Enforcement has developed in connection with it. If there were any, of course, the standard would be controlling. The standard specifies a drop height, and a 'guided free fall' from that height. We consider 'free fall' to be an objective and unambiguous physical term, meaning a movement in response to the force of gravity unimpeded by any resistance except air resistance. The requirement the equipment must be capable of meeting, therefore, refers to a fall in which the guiding method imparts no significant resistance, *i.e.*, it does not affect the results. Although in practice a perfectly frictionless guided fall may be unachievable, a manufacturer must ensure that his product would meet the requirement no matter how small the friction. An analogy is the fixed collision barrier defined in S 49 CFR 571.3, which requires a vehicle to meet a barrier crash test requirement using a barrier that absorbs no significant part of the vehicle's energy. Helmet manufacturers must assume, therefore, that the government will test their products using test fixtures that impart as little friction to the fall as possible. We therefore consider the issue of what systems were 'in general use at the time ANS Z90.1 and FMVSS 218 were written' to be irrelevant to the question of compliance.; This discussion should answer your first two questions. We do no accord any legal status to 'old' test procedures as opposed to 'new' ones. With regard to the question about correlation studies, we have not conducted any and I know of no plans to do so. Finally, Standard 218 presently covers only size C helmets because drawings and headforms for the other sizes are not yet available. Therefore, no formal compliance testing can be done on other sizes of helmets. We hope soon to publish drawings and make available models of size A, B and D headforms, at which time a date will be set for extending Standard 218 to these other sizes. Your continuing interest in motorcycle safety is greatly appreciated.; Sincerely, Frank Berndt, Acting Chief Counsel |
|
ID: aiam1704OpenMr. James P. Coughlin, Vice President - Marketing, Bell Helmets Inc., 2850 Long Beach, CA 90806; Mr. James P. Coughlin Vice President - Marketing Bell Helmets Inc. 2850 Long Beach CA 90806; Dear Mr. Coughlin: This responds to your letter of November 14, 1974, asking whether FMVS 218 applies to helmets intended for use by riders of moped cycles.; The answer to your question is yes. Standard 218 applies to 'helmet designed for use by motorcyclists and other motor vehicle users.' A 'moped' is a 'motor vehicle' (15 U.S.C. 1391), it is also a 'motorcycle,' and specifically a 'motor-driven cycle' (49 CFR 571.3). Since a motorcyclist is any rider of a motorcycle, Standard 218 clearly applies to helmets designed for use by motor driven cycle riders.; As you are probably aware, the States and their political sudivision have jurisdiction over the circumstances under which helmets must be worn. Thus a State could conceivably exclude motor-driven cycles from the coverage of its helmet use law. But this would not affect the obligation of your company to manufacture to comply with Standard 218 all helmets which you intend to be used in connection with the operation of a motor vehicle.; Yours truly, Richard B. Dyson, Acting Chief Counsel |
|
ID: aiam1703OpenMr. James P. Coughlin, Vice President - Marketing, Bell Helmets Inc., 2850 Long Beach, CA 90806; Mr. James P. Coughlin Vice President - Marketing Bell Helmets Inc. 2850 Long Beach CA 90806; Dear Mr. Coughlin: This responds to your letter of November 14, 1974, asking whether FMVS 218 applies to helmets intended for use by riders of moped cycles.; The answer to your question is yes. Standard 218 applies to 'helmet designed for use by motorcyclists and other motor vehicle users.' A 'moped' is a 'motor vehicle' (15 U.S.C. 1391), it is also a 'motorcycle,' and specifically a 'motor-driven cycle' (49 CFR 571.3). Since a motorcyclist is any rider of a motorcycle, Standard 218 clearly applies to helmets designed for use by motor driven cycle riders.; As you are probably aware, the States and their political sudivision have jurisdiction over the circumstances under which helmets must be worn. Thus a State could conceivably exclude motor-driven cycles from the coverage of its helmet use law. But this would not affect the obligation of your company to manufacture to comply with Standard 218 all helmets which you intend to be used in connection with the operation of a motor vehicle.; Yours truly, Richard B. Dyson, Acting Chief Counsel |
|
ID: aiam1752OpenMr. John C. Bennett, Chairman of the Board, Utility Trailer Manufacturing Co., City of Industry, CA 91749; Mr. John C. Bennett Chairman of the Board Utility Trailer Manufacturing Co. City of Industry CA 91749; Dear Mr. Bennett: This responds to your January 8, 1975, request for reconsideration o our determination, in a January 3, 1975, letter to Mr. J. B. Markovich, that a bulk transport trailer designed for transporting farm commodities from the field to processing plants over private and public roads does not qualify for exemption from Standard No. 121, *Air brake systems*, as an agricultural vehicle.; There is no specific exemption for agricultural machinery in th language of the 'National Traffic and Motor Vehicle Safety Act of 1966' (15 U.S.C. 1391 et seq.), and there is little legislative history on the subject. We have concluded that Congress only intended to exclude agricultural machinery that is designed for working on the fields--implements of husbandry--and whose on-road use is strictly limited, at low speeds, and only incidental to its main function.; The NHTSA has interpreted the definition of 'motor vehicle' to agre with this Congressional intent. Our criteria for a 'non-motor vehicle' have been (1) a maximum speed not exceeding 20 mph, and (2) an abnormal configuration which distinguishes it from the traffic flow. These criteria separate 'agricultural machinery' from those vehicles which are related to agriculture but use the highways as a primary purpose.; The NHTSA does not interpret 'motor vehicle' to exempt a vehicle whic has a highway speed capability, even if it uses the highway infrequently. For example, house trailers are subject to safety standards although they sometimes use the highways only once to be moved to a permanent homesite. Mobile cranes and drill rigs which use the highways between job sites are another vehicle type which has also been determined to be a motor vehicle. The important consideration is that their configuration permits unlimited use of the highways.; From your description, your bulk transport trailers are capable o highway speed and use the highway in the same way as other air-braked full trailers. Accordingly, your request for reclassification is denied.; You mentioned difficulty in meeting Standard No. 121's parking brak requirements. I enclose a copy of correspondence on this same matter with a railroad company that finds it necessary to manually release parking brakes under some circumstances.; Sincerely, |
|
ID: aiam2263OpenMr. G.E. Adams, Technical Manager, Dunlop Limited, Engineering Group, Holbrook Lane Coventry CV6 4AA, England; Mr. G.E. Adams Technical Manager Dunlop Limited Engineering Group Holbrook Lane Coventry CV6 4AA England; Dear Mr. Adams: This is in response to your letter of March 17, 1976, requestin information concerning steps which you, as a manufacturer of wheel equipment which will be offered for importation into the United States, must take in order to comply with all applicable National Highway Traffic Safety Administration regulations.; You should be aware of 49 CFR Part 566, *Manufacturer Identification* and 49 CFR Part 573, *Defect Reports*. In addition, Federal Motor Vehicle Safety Standard No. 119, *New Pneumatic Tires for Vehicles Other Than Passenger Cars*, may be of interest to you. Copies of these rules and an information sheet entitled 'Where to Obtain Federal Motor Vehicle Safety Standards and Regulations' are enclosed for your convenience.; Section 110(e) of the National Traffic and Motor Vehicle Safety Act (1 U.S.C. S1399(e)) requires every manufacturer who offers a motor vehicle or item of motor vehicle equipment for importation into the United States to designate a permanent resident of the United States as his agent, upon whom service of all processes, orders, notices, decisions, and requirements may be made.; The procedural regulations (49 CFR 551.45) for designation of agen pursuant to the Act requires that it include:; >>>(1) A certification by its maker that the designation is binding o Dunlop Limited under the laws, corporate bylaws, or other requirements governing the making of the designation at the time and place where it is made,; (2) The full legal name, principle place of business and mailin address of Dunlop Limited,; (3) Trade names or other designations of origin of the products o Dunlop Limited that do not bear its legal name,; (4) A provision that the designation of agent remain in effect unti with drawn or replaced by Dunlop Limited,; (5) A declaration of acceptance duly signed by the agent appointed which may be an individual, a firm, or a U.S. Corporation, and (6) The full legal name and address of the designated agent.<<<; A copy of the procedural regulation for designation of agent i enclosed for your convenience.; Sincerely, John Womack, Assistant Chief Counsel |
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.