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: aiam4876OpenMs. Vicki Haudler 4636 S. Cedar Lake Rd. St. Louis Park, MN 55416; Ms. Vicki Haudler 4636 S. Cedar Lake Rd. St. Louis Park MN 55416; "Dear Ms. Haudler: This responds to your letter seeking furthe information about a possible determination to be made by the Secretary of Transportation under Federal Motor Vehicle Safety Standard No. 208 (49 CFR 571.208). S4.1.4.1 of Standard No. 208 provides that cars manufactured on or after September 1, 1989 must be equipped with automatic crash protection. Vehicles equipped with automatic crash protection protect their occupants by means that require no action by vehicle occupants. Compliance with the minimum performance requirements of Standard No. 208 is determined in a dynamic crash test. That is, a vehicle must comply with specified injury criteria, as measured on a test dummy, when tested by this agency in a 30 mph barrier crash test. The two types of automatic crash protection currently offered on new passenger cars are automatic safety belts (which help to assure belt use) and air bags (which supplement safety belts and offer some protection even when safety belts are not used). As you noted in your letter, S4.1.5 of Standard No. 208 provides that: 'If the Secretary of Transportation determines, by not later than April 1, 1989, that state mandatory safety belt usage laws have been enacted that meet the criteria specified in S4.1.5.2 and that are applicable to not less than two-thirds of the total population . . ., the automatic restraint requirements will not go into effect .' You asked whether the Secretary ever made a determination under S4.1.5 regarding State safety belt use laws. The answer is no. Under S4.1.5, the Secretary was not required to make any determination about any State safety belt laws. In fact, the Secretary never did so. Because no determination was made under S4.1.5, the automatic restraint requirements went into effect as of September 1, 1989 for all passenger cars. I have returned the self-addressed, stamped envelope you enclosed in your letter. Good luck in your legal career. Sincerely, Paul Jackson Rice Chief Counsel"; |
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ID: aiam3356OpenMr. C. Rodney Kuhns, 132 Frement Place, Los Angeles, CA 90005; Mr. C. Rodney Kuhns 132 Frement Place Los Angeles CA 90005; Dear Mr. Kuhns: This responds to your letter of August 10, 1980, in which you as whether your proposed urban transport vehicle would be classified as an automobile or a motorcycle.; The agency's definition of 'motorcycle' is given in 49 CFR S 571.3 which reads in part:; >>>'Motorcycle' means a motor vehicle with motive power having a sea or saddle for the use of the rider and designed to travel on not more than three wheels in contact with the ground.<<<; Based on our understanding of your drawings, your proposed vehicle ha more than three wheels. If our understanding is correct, your vehicle would be classified as a passenger car rather than as a motorcycle.; The requirements for passenger cars are more stringent than fo motorcycles. We have enclosed a pamphlet prepared by the agency which gives a brief summary of the requirements and applicability of each of the Federal motor vehicle safety standards (issued as of August 1978). However, because of the volume of these standards, we do not provide copies directly. We have enclosed an information sheet which explains how you can obtain up-to-date copies of our standards and other regulations.; This agency does not license any vehicles for street or highway use Licensing is handled by the States. We specify performance requirements, and any motor vehicle must be certified by its manufacturer as being in compliance with all applicable safety standards as of the date of its manufacture. If the vehicle complies with these requirements, we specify no further steps which must be taken.; The agency will provide confidential treatment for your letter an accompanying drawings.; Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam3357OpenMr. C. Rodney Kuhns, 132 Frement Place, Los Angeles, CA 90005; Mr. C. Rodney Kuhns 132 Frement Place Los Angeles CA 90005; Dear Mr. Kuhns: This responds to your letter of August 10, 1980, in which you as whether your proposed urban transport vehicle would be classified as an automobile or a motorcycle.; The agency's definition of 'motorcycle' is given in 49 CFR S 571.3 which reads in part:; >>>'Motorcycle' means a motor vehicle with motive power having a sea or saddle for the use of the rider and designed to travel on not more than three wheels in contact with the ground.<<<; Based on our understanding of your drawings, your proposed vehicle ha more than three wheels. If our understanding is correct, your vehicle would be classified as a passenger car rather than as a motorcycle.; The requirements for passenger cars are more stringent than fo motorcycles. We have enclosed a pamphlet prepared by the agency which gives a brief summary of the requirements and applicability of each of the Federal motor vehicle safety standards (issued as of August 1978). However, because of the volume of these standards, we do not provide copies directly. We have enclosed an information sheet which explains how you can obtain up-to-date copies of our standards and other regulations.; This agency does not license any vehicles for street or highway use Licensing is handled by the States. We specify performance requirements, and any motor vehicle must be certified by its manufacturer as being in compliance with all applicable safety standards as of the date of its manufacture. If the vehicle complies with these requirements, we specify no further steps which must be taken.; The agency will provide confidential treatment for your letter an accompanying drawings.; Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam0938OpenMr. Bernard P. O'Meara, Center for Auto Safety, 800 National Press Building, Washington, DC 20004; Mr. Bernard P. O'Meara Center for Auto Safety 800 National Press Building Washington DC 20004; Dear Mr. O'Meara: Thank you for your letter of 29 November, 1972, concerning allege non-compliance of the Defect Information Report regarding Volkswagen Windshield Wipers, submitted by Volkswagen of America on October 12, 1972, with the requirements of NHTSA's Defect Reports Regulations, 49 CFR Part 573. We agree that Volkswagen has failed to supply information required by Sections 573.4(c)(2) and 573.4(c)(6) of the Regulation, specifically, the months of manufacture of the affected vehicles and a chronology which includes warranty claims, field service bulletins, and other such information. We are contacting Volkswagen to determine why the Company has failed to furnish that information and to attempt to obtain it. We also agree with your conclusion that 100% of 1948-1969 Volkswagens are potentially affected by the windshield wiper defect. However, Volkswagen's statement that 'no information is available' as to either the total number of such vehicles operating in the United States, or the percentage potentially affected satisfies the disclosure requirement of the regulation (49 CFR 573.4(c)(3, 4)).; We cannot agree, however, with your remaining assertions o non-compliance with the Regulations. While the Volkswagen Information Report is lacking in detail and is a poor example of an informational communication, it does contain minimal responses to the enumerated requirements of the Regulations.; Thank you for your interest in motor vehicle safety. Sincerely, Lawrence R. Schneider, Chief Counsel |
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ID: aiam5186OpenMr. Shawn Shieh Ventures International USA 1141 N. Columbus Ave., Suite 303 Glendale, CA 91202; Mr. Shawn Shieh Ventures International USA 1141 N. Columbus Ave. Suite 303 Glendale CA 91202; Dear Mr. Shieh: This replies to your undated letter to the Office o Enforcement, NHTSA, asking questions about an emergency communication product intended to be permanently mounted in the back window of an automobile. The product uses light emitting diodes to form messages for the drivers of following cars to read. I enclose a copy of a letter dated August 17, 1989, that the agency sent to Alan S. Eldahr who asked for our comments on a similar device. The same advice applies to your product. As you will see, our opinion is that the product is of doubtful legality under Federal law when used on passenger cars manufactured on or after September 1, 1985, which are equipped with center highmounted stoplamps. In addition, the product must not create a noncompliance with the Federal field of view requirements for interior rear view mirrors. Thus, we cannot answer your question about the maximum size of a permanent structure to be installed in an automobile because that will vary from car to car. With respect to your other questions, there are no Federal specifications for the material of the base support. The 'restriction' on the product's wiring is that it must not interfere with the functioning of any Federally required lamp on the vehicle. This agency is the only government agency you have to consult on the product. Sincerely, John Womack Acting Chief Counsel Enclosure; |
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ID: aiam2887OpenMr. R. W. Cheetham, Director, Quality Assurance, The Armstrong Rubber Company, 500 Sargent Drive, New Haven, CT 06507; Mr. R. W. Cheetham Director Quality Assurance The Armstrong Rubber Company 500 Sargent Drive New Haven CT 06507; Dear Mr. Cheetham: This is in response to your letter of October 19, 1978, requestin approval of the tread labels Armstrong Rubber Company proposes to use in satisfaction of the labeling requirements of the Uniform Tire Quality Grading Standards (UTQGS)(49 CFR 575.104(d)(1)(i)(B)). You propose to include the applicable UTQGS grades for a particular tire on a tread label identifying the tire brand, type and size. A separate label would contain the general grading information from Figure 2 of the rule, including a listing of all possible traction and temperature grades, with the text on the label oriented along the tread circumference instead of across it.; Part 575.104(d)(1)(i)(B) requires that each passenger car replacemen tire, other than a snow tire or temporary use spare tire, have affixed a tread label containing both the specific UTQGS grades for the tire and an explanation of the grades in the form illustrated in Figure 2. Thus, the specific grades for the tire must appear on the same label that contains the explanation of the grading system. The regulation calls for a depiction of all possible traction and temperature grades with the grades applicable to the specific tire indelibly circled.; While the National Highway Traffic Safety Administration (NHTSA) has n objection to the inclusion of the required UTQGS information on the same label with other data such as tire size and brand name, failure to provide the required explanations on the same label with the applicable tire grades is not permitted by the regulation. Your proposed labels also fail to meet the regulation's requirement that applicable traction and temperature grades be denoted by circling the appropriate letter in a display of all possible grades. Finally, the general UTQGS information in your proposal is not in the form illustrated in Figure 2, since the text in your example will appear along the tread rather than at right angles as specified by Figure 2.; While your proposed tread labels do not meet the present requirement of Part 575.104(d)(1)(i)(B), NHTSA will treat your letter as a petition for rulemaking and consider amending the UTQG regulation to permit greater flexibility in tread labeling.; Sincerely, Joseph J. Levin, Jr., Chief Counsel |
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ID: aiam2889OpenMr. R. W. Cheetham, Director, Quality Assurance, The Armstrong Rubber Company, 500 Sargent Drive, New Haven, CT 06507; Mr. R. W. Cheetham Director Quality Assurance The Armstrong Rubber Company 500 Sargent Drive New Haven CT 06507; Dear Mr. Cheetham: This is in response to your letter of October 19, 1978, requestin approval of the tread labels Armstrong Rubber Company proposes to use in satisfaction of the labeling requirements of the Uniform Tire Quality Grading Standards (UTQGS)(49 CFR 575.104(d)(1)(i)(B)). You propose to include the applicable UTQGS grades for a particular tire on a tread label identifying the tire brand, type and size. A separate label would contain the general grading information from Figure 2 of the rule, including a listing of all possible traction and temperature grades, with the text on the label oriented along the tread circumference instead of across it.; Part 575.104(d)(1)(i)(B) requires that each passenger car replacemen tire, other than a snow tire or temporary use spare tire, have affixed a tread label containing both the specific UTQGS grades for the tire and an explanation of the grades in the form illustrated in Figure 2. Thus, the specific grades for the tire must appear on the same label that contains the explanation of the grading system. The regulation calls for a depiction of all possible traction and temperature grades with the grades applicable to the specific tire indelibly circled.; While the National Highway Traffic Safety Administration (NHTSA) has n objection to the inclusion of the required UTQGS information on the same label with other data such as tire size and brand name, failure to provide the required explanations on the same label with the applicable tire grades is not permitted by the regulation. Your proposed labels also fail to meet the regulation's requirement that applicable traction and temperature grades be denoted by circling the appropriate letter in a display of all possible grades. Finally, the general UTQGS information in your proposal is not in the form illustrated in Figure 2, since the text in your example will appear along the tread rather than at right angles as specified by Figure 2.; While your proposed tread labels do not meet the present requirement of Part 575.104(d)(1)(i)(B), NHTSA will treat your letter as a petition for rulemaking and consider amending the UTQG regulation to permit greater flexibility in tread labeling.; Sincerely, Joseph J. Levin, Jr., Chief Counsel |
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ID: aiam0778OpenMr. G. L. Hartman, Group Staff Engineer, Superior Coach Division, Sheller-Globe Corporation, Lima, OH 45802; Mr. G. L. Hartman Group Staff Engineer Superior Coach Division Sheller-Globe Corporation Lima OH 45802; Dear Mr. Hartman: This is in reply to your letter of June 23, 1972, concerning th Certification and related regulations (49 CFR Parts 567, 568). You indicate in your letter that many school bus bodies are exceeding by small amounts the weight ratings specified for the chassis by the incomplete manufacturer, and that increasing the capability of the chassis results in expenditures which you believe are not justified by the additional safety achieved. You indicate also that you believe that section 567.5 requires the final-stage manufacturer to use the incomplete vehicle ratings for his ratings, except when differing tire sizes are specified in accordance with 567.4(h).; You appear to be misinterpreting the regulations. There is n requirement that a final-stage manufacturer use the ratings provided by the incomplete vehicle manufacturer. The final-stage manufacturer is free to raise them for purposes of certification, as long as the values he chooses are consistent with the definitions of GAWR and GVWR. If he does raise them, however, he can no longer rely on the assurances of the incomplete vehicle manufacturer as to conformity with the standards, but will be responsible, subject to the Vehicle Safety Act's penalties, for (1) conformity of the vehicle with all applicable standards, and (2) ensuring that no safety problem has been created. If the final-stage manufacturer will not assume this responsibility, in our opinion he cannot reasonably maintain that the limitations imposed by the incomplete manufacturer's ratings are unjustified.; In short, you are free to choose and combine your components as you se fit, as long as you use due care to ensure that the vehicle conforms to the standards and contains no safety-related defects. Observing the component manufacturer's maximum load ratings is usually the easiest way to do this.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam2090OpenMr. Tokio Iinuma, Staff Safety, Nissan Motor Co., Ltd., P.O. Box 1606, Englewood Cliffs, NJ 07632; Mr. Tokio Iinuma Staff Safety Nissan Motor Co. Ltd. P.O. Box 1606 Englewood Cliffs NJ 07632; Dear Mr. Iinuma: This is in reply to your letter of September 8, 1975, to Mr. Bernd requesting an interpretation of the visibility requirements specified in paragraph S4.3.1.1 of Federal Motor Vehicle Safety Standard No. 108.; Specifically, you ask whether a front turn signal lamp which i partially obscured by the radiator grille as shown on a drawing that you enclosed would meet the specified visibility requirements, if . . .; >>>'1. The lamp met the photometric requirements under the state o being equipped on the vehicle.; 2. We could easily observe through all the photometric test angles tha the lamp was activated.'<<<; If condition 1 above is met, the lamp would appear to comply with th visibility requirements of paragraph S4.3.1.1.; For condition 2 above, SAE Standard J588d, incorporated by reference i Standard No. 108, specifies in part that signals from lamps mounted on the left and right sides of the vehicle shall be visible through a horizontal angle of 45 degrees to the left and right respectively. To be considered visible, the lamp must provide an unobstructed projected illuminated area of outer lens surface, excluding that portion of the lens that may serve as a reflex reflector, at least 2 square inches in extent, measured at 45 degrees to the longitudinal axis of the vehicle. If your design meets the specified requirements, the lamp would also be in compliance with the requirements of paragraph S4.3.1.1.; As you were informed in a meeting with Messrs. Leysath and Vinson o this agency on September 8, 1975, it is not necessary that the entire lamp as partially obscured comply with Standard No. 108. If either the upper or lower portion of the lamp meets the photometric and visibility requirements, that is sufficient for conformance. If certification is based upon the lower portion alone, however, the center of the lower portion must be mounted not less than 15 inches above the pavement.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam2092OpenMr. Richard L. Kreutziger, Coach and Equipment Sales Corp., P.O. Box 36, Penn Yan, NY 14527; Mr. Richard L. Kreutziger Coach and Equipment Sales Corp. P.O. Box 36 Penn Yan NY 14527; Dear Mr. Kreutziger: This is in response to your letter of July 30, 1975, to Mr. Schwartz o this office, seeking an interpretation of Federal Motor Vehicle Safety Standard No. 205.; FMVSS No. 205 requires that the prime glazing manufacturer certify eac piece of glazing covered by the standard by marking it with the letters DOT, the manufacturers code mark assigned by the Department of Transportation and the markings required by section 6 of A.N.S.Z-26. The latter markings are the 'AS' number, the model number and the manufacturer's distinctive designation or trademark. The distributor who cuts a section of glazing material to which the standard applies is required to mark the material in accordance with section 6 of A.N.S.Z-26. Thus, each of the rectangular lites should be marked with the manufacturer's model number and trademark in addition to the AS number, but not with the letters DOT or the prime glazing manufacturer's DOT number.; Section 114 of the National Traffic and Motor Vehicle Safety Act o 1966 requires that you, as the vehicle manufacturer, certify that your product conforms to all applicable Federal motor vehicle safety standards. This would, of course, include FMVSS No. 205.; I hope I have fully answered your questions. If you have any furthe need for information please do not hesitate to write.; Sincerely, Frank A. Berndt, Acting 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.