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 |
|---|---|
| search results table | |
ID: aiam3910OpenMr. Gordon Bonvallet, Manager, Photometric Division, ETL Testing Laboratories, Inc., P.O. Box 2040, Cortland, NY 13045- 2040; Mr. Gordon Bonvallet Manager Photometric Division ETL Testing Laboratories Inc. P.O. Box 2040 Cortland NY 13045- 2040; Dear Mr. Bonvallet: This is in reply to your letter of February 4, 1985, asking for a interpretation of the humidity testing procedure for replaceable bulb headlamps.; Paragraph S6.8 of Motor Vehicle Safety Standard No. 108 states i pertinent part that after completion of the test cycle in which the headlamp shall have been in an environment of 100 degrees Fahrenheit with a relative humidity of 90 *+* 10 percent, it shall then be in an environment with a temperature of 73 degrees Fahrenheit and relative humidity of 30 *+* 10 percent before removal for photometric testing. You believe that this implies an instantaneous transition in temperature/humidity conditions which, in your view, is 'impossible to achieve.' You have set forth three alternative procedures and ask which is the most acceptable to this agency.; Under your first alternative, the temperature and humidity in th humidity chamber would be reduced to 73 degrees Fahrenheit-43 percent, requiring about an hour, whereupon the headlamp would be removed to a 'dry box' chamber of the requisite temperature/humidity before photometric testing. In the second alternative, there would be no such removal before the photometric testing. In the third alternative, the headlamp would be removed from the humidity chamber and immediately carried to a 'dry box' with the requisite temperature/humidity, however, in your test set up this would require three to five minutes elapsed time between chambers.; Paragraph S6.8 does not specify a humidity of 43 percent in any of it test conditions, and a procedure incorporating the first and second alternatives clearly would not be in accordance with paragraph S6.8. That paragraph, however, does not specify that the temperature/humidity sequences must occur in the same chamber but it does imply that the lower temperature/humidity soak should take place directly following the higher temperature/humidity one. Therefore, your third alternative is the one that meets the intent of paragraph S6.8. To insure consistency of results, we recommend that no transfer period exceed three minutes and that the headlamp be exposed as briefly and as little as possible to the ambient temperature/humidity of the test laboratory.; Sincerely, Jeffrey R. Miller, Chief Counsel |
|
ID: aiam2602OpenMrs. J. A. Selsemeyer, 5911 Cape Cod Court, Indianapolis, IN 46250; Mrs. J. A. Selsemeyer 5911 Cape Cod Court Indianapolis IN 46250; Dear Mrs. Selsemeyer: This responds to your April 1, 1977, letter asking several question concerning a manufacturer's responsibility for tires installed as original equipment on a passenger car.; You asked the following questions in your letter: >>>1. Are there any laws now in effect which pinpoint responsibilit for the quality of tires received as original equipment on a new car?<<<; Section 159 of the National Traffic and Motor Vehicle Safety Act o 1966 (the Act) (15 U.S.C. 1381 *et seq*.) places responsibility upon the vehicle manufacturer for compliance of original equipment with motor vehicle safety standards. However, Section 159 gives the National Highway Traffic Safety Administration the authority to shift to the tire manufacturer the responsibility for compliance of tires with Federal safety standards. You should note that the Act establishes responsibility for compliance with Federal regulations and does not establish remedies for litigants in private law suits.; >>>2. Is it true that there is a federal law which makes it mandator for United States auto manufacturers to buy original equipment tires in equal amounts from each domestic manufacturer of tires? If so, may I have a copy of this law?<<<; There are no Federal laws of which we are aware that require vehicl manufacturers to purchase equal numbers of tires from each tire manufacturer.; >>>3. What is the current status of safety testing as provided by la in 1966, but never implemented? This law was to be effective January 1, 1976 for radial tires, July 1, 1976 for bias-belted tires, and January, 1977 for bias- ply tires. Was it? If not, what are the prospects?<<<; The regulation to which you refer is known as Uniform Tire Qualit Grading and is found in the Code of Federal Regulations, Title 49, Part 575. The effective dates for implementation of tire quality grading standards for the three tire types you mention have been delayed by litigation. The agency intends to establish new effective dates shortly.; >>>4. Can a customer of General Motors ask for and receive a servic agreement for the tires at the time of sale of a car?<<<; This is a contractual matter between the purchaser of a motor vehicl and General Motors. Federal regulations neither encourage nor discourage such arrangements.; Sincerely, Joseph J. Levin, Jr., Chief Counsel |
|
ID: aiam2252OpenHonorable Mark Andrews, House of Representatives, Washington, DC 20515; Honorable Mark Andrews House of Representatives Washington DC 20515; Dear Mr. Andrews: This is in response to your letter of March 19, 1976, requesting ou comments on an inquiry from one of your constituents, Mr. Pat Milloy, concerning the proper format for disclosure of odometer mileage information in compliance with the Federal odometer disclosure regulation (49 CFR Part 580).; Mr. Milloy states in his letter that a Colorado dealer, orderin odometer disclosure forms, has indicated that the required Federal format has been changed. The format referred to by the Colorado dealer differs from the Federal form which Mr. Milloy and his client, Globe-Gazette Printing Company, believe to still be in force.; The Federal odometer disclosure regulation has not been amended sinc its initial enactment. The format requested by the Colorado dealer (form 'B' enclosed in Mr. Milloy's letter) fails to comply with the current Federal odometer disclosure requirements in several respects. The statement referring to the mileage indicated on the odometer at the time of the vehicle's transfer must be phrased to indicate that the disclosure document was executed at the time of the vehicle's transfer, not at some later time. In addition, the statement must be written in such a manner that it is clear it is to be completed by the transferor alone. To satisfy these criteria the statement should read:; >>>'I, * *, state that the odometer mileage indicated on the vehicl described above, at the time of transfer to * * is as follows:'<<<; The portion of the document provided for disclosure of the odomete mileage and a statement as to its accuracy is also deficient. Instructions are necessary on this part of the form to ensure that it is completed in a consistent manner by all persons. The number of miles indicated on the odometer at the time of the vehicle's transfer need not appear a second time if the form includes the statement recommended above. If the seller wishes, he may indicate on the form that the actual mileage is over 100,000 miles. In addition, the statement concerning the accuracy of the vehicle's reflected mileage must be more complete than the one included in form 'B'. Completion of the disclosure document in accordance with these directions may be accomplished as follows:>>>; '(Where applicable, complete line 1 and/or check line 2:) 1. * *, total cumulative miles (if over 100,000). 2. [ ] I further state that the actual mileage differs from th odometer reading for reasons other than odometer calibration error and that the actual mileage is unknown.'<<<; The odometer regulation's provisions do not require that the transfere sign the statement nor do they make it necessary to have the document notarized. In addition, the date on which the transferor purchased the vehicle need not be provided.; As long as the requirements of the disclosure regulation are satisfied there is no limitation on including additional information in the disclosure statement. Thus, modifying the statement 'B' format to meet the Federal requirements in the manner described above would be sufficient for compliance by the Colorado dealer. The additional information appearing in form 'B' may be retained without affecting compliance.; I hope this letter answers Mr. Milloy's questions concerning th Federal odometer disclosure requirements. If I can be of any further assistance, please do not hesitate to let me know.; Sincerely, Frank Berndt, Acting Chief Counsel |
|
ID: aiam5597OpenMr. Bryan Couch Systems Zone Leader Motor Coach Industries Door 10 475 Clarence Avenue Winnipeg, Manitoba R3T IT5 Canada; Mr. Bryan Couch Systems Zone Leader Motor Coach Industries Door 10 475 Clarence Avenue Winnipeg Manitoba R3T IT5 Canada; Dear Mr. Couch: This responds to your FAX of August 8, 1995, asking fo our comments on a 'preliminary drawing showing our proposed location for the front marker lamp and supplementary front marker lamp.' The front marker lamp will meet all photometry requirements of Federal Motor Vehicle Safety Standard No. 108 and, in your opinion, will be placed as far forward as practicable on the vehicle. The supplementary lamp will not meet the 45 degree rearward photometry requirement. We have only a couple of comments. The first is that initially the determination of practicability of the location of the front side marker lamps is that of the vehicle manufacturer who certifies compliance with Standard No. 108, and NHTSA will not question that determination unless it appears clearly erroneous. In this instance, we see no reason to question your opinion. Our second comment is that a supplementary side marker lamp need not meet any of the requirements for side marker lamps, it must not, however, as provided in paragraph S5.1.3 of Standard No. 108, impair the effectiveness of any lighting equipment installed to meet the requirements of Standard No. 108. Given the small size and candela output of side marker lamps, we do not believe that your supplementary side marker lamp would have this effect. If you have any further questions, you may refer them to Taylor Vinson of this Office (phone: 202-366-5263). Sincerely, John Womack Acting Chief Counsel; |
|
ID: aiam1887OpenMr. R. Wieman, Ohio Hydraulics, 2510 E Sharon Road,Cincinnati, Ohio 45241; Mr. R. Wieman Ohio Hydraulics 2510 E Sharon Road Cincinnati Ohio 45241; Dear Mr. Wieman: #This responds to your letter of March 7, 1975, to Mr Francis Armstrong of this agency, concerning possible changes if Federal Motor Vehicle Safety Standard No. 106-74, *Brake Hoses*. #On March 4, 1975, the NHTSA proposed a change in the definition of 'brake hose assembly' which would exclude from the standard's requirements certain assemblies made for repair of used vehicles (40 F.R. 8962, copy enclosed.) As proposed, the change would not exclude assemblies made by hose distributors. Several of the comments responding to the proposal have suggested that such distributor-made assemblies also be excluded, #When a final decision is made on this issue, it will be published in the Federal Register. #Yours truly, Richard B. Dyson, Assistant Chief Counsel; |
|
ID: aiam0795OpenMr. F. Michael Petler, Assistant Manager, Product Development Department, U. S. Suzuki Motor Corporation, 13767 Freeway Drive, Santa Fe Springs, CA 90670; Mr. F. Michael Petler Assistant Manager Product Development Department U. S. Suzuki Motor Corporation 13767 Freeway Drive Santa Fe Springs CA 90670; Dear Mr. Petler:#In a telephone call subsequent to receiving our answe of July 20 to your letter of July 11, you indicated that you were concerned with a different question from the one we answered regarding the Suzuki handlebar switches you enclosed. The question you had in mind was whether the direction of movement of the switches was sufficiently vertical to satisfy the requirement for 'up' and 'down' positions.#The switches you submitted move in an arc at approximately 45 degrees from the vertical. Since they have in that position a substantial vertical component, we consider that they would conform in that respect with the requirements of the standard.#Yours truly, Richard B. Dyson, Assistant Chief Counsel; |
|
ID: aiam3013OpenMr. Jack W. Sperr, Coordinator, Pupil Transportation, Department of Education, 942 Lancaster Drive, N.E., Salem, OR 97310; Mr. Jack W. Sperr Coordinator Pupil Transportation Department of Education 942 Lancaster Drive N.E. Salem OR 97310; Dear Mr. Sperr: This responds to your April 6, 1979, letter asking several question about the applicability of the school bus safety standards to van-type vehicles.; First, you ask whether a vehicle that transports more than 10 person and is constructed in accordance with the school bus safety standards must be painted, lighted and marked as a school bus. As you know, Highway Safety Program Standard No. 17 formerly permitted Type II school vehicles, under 16 passengers, to be marked, painted, and lighted at the option of the school district. As a result of the Motor Vehicle and Schoolbus Safety Amendments of 1974 (Pub. L. 93-492), all school buses must be equipped with school bus lights. Since they must have lights, they must also be painted and marked as school buses. Therefore, all school vehicles carrying more than 10 persons must be properly painted, marked and lighted.; In your second question you ask whether a school can purchase and use noncomplying used van manufactured after April 1, 1977. The National Highway Traffic Safety Administration (NHTSA) regulates, for the most part, vehicles up to the point of first purchase. Therefore, the sale of a noncomplying used vehicle would be beyond the control of this agency. However, we caution schools purchasing such vehicles that they may be unable to insure them, and they may be responsible for significantly increased liability in the event of an accident. Further, we encourage States not to license such vehicles for the transportation of school children.; Third, you ask whether the standard applies to leased or rente vehicles. The answer to your question is yes. Part 571.3 of our regulations (49 CFR 571) defines school bus as 'a bus that is sold, or introduced in interstate commerce,...' The phrase introduced in interstate commerce includes the lease or rental of vehicles for school use. Since these leased or rented vehicles are considered school buses, they must comply with the safety standards.; In your fourth question, you ask whether a contractor or school ca remove seats from a van that it inadvertently purchased so that as modified it will transport 10 or fewer persons. A school or contractor can modify its own vehicles any way that it chooses. A dealer, manufacturer, or repair business, on the other hand, cannot alter a vehicle in any manner that would render inoperative its compliance with Federal safety standards. The agency notes that if a school removes seats from the van in the manner suggested in your letter, the van would no longer be required to comply with the school bus safety standards. However, a new van-type vehicle that transports 10 or fewer persons must comply with safety standards applicable to multipurpose passenger vehicles (MPV). Your modified vehicle probably would not comply with these MPV requirements. You should remember that the operation of a noncomplying school bus or a noncomplying MPV does not subject a school to liability to the NHTSA. However, a school's private liability in the event of an accident might be increased.; In your final question, you ask whether the NHTSA is enforcing th school bus regulations. The agency has taken extensive steps to enforce its school bus regulations. These include a major testing program of buses manufactured in compliance with the standards. As a result of these tests, some noncompliances have been determined and some remedies have occurred. With respect to the sale of vans as school vehicles, the agency has warned many dealers of the illegality of this practice, and in most instances, these dealers have repurchased the vehicles that were sold in violation of the law.; We encourage States to adopt licensing practices that ensure tha vehicles used to transport school children and manufactured after April 1, 1977, comply with the safety standards. Many States now have such licensing programs, and the problem of van misuse is rapidly diminishing in those areas. We further encourage States to report instances of violations to our Office of Vehicle Safety Compliance. That Office will take the necessary steps to enforce the law.; Sincerely, Frank Berndt, Acting Chief Counsel |
|
ID: aiam4386OpenMr. Thomas S. Pieratt, Jr., Executive Secretary, Truck Equipment & Body Distributors Assoc., 602 Main Street, Cincinnati, OH 45202; Mr. Thomas S. Pieratt Jr. Executive Secretary Truck Equipment & Body Distributors Assoc. 602 Main Street Cincinnati OH 45202; Dear Mr. Pieratt: With reference to your phone conversation with Make Peskoe on Septembe 8, I have enclosed a copy of an NHTSA opinion which concludes that a person adding a snow plow to a completed vehicle is not required to certify the vehicle. In such a case, the existing certification label should be left in place. You should note that the opinion also states that if the mounting of the snow plow causes the vehicle not to conform to any applicable motor vehicle safety standard, and the vehicle is not brought back into conformity before sale, the person mounting the plow will be violating section 108(a)(1) of the National Traffic and Motor Vehicle Safety act, and will be subject to civil penalties and other sanctions as prescribed in sections 109 and 110 of the Act.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam3443OpenMr. M. S. Keshav, Manager (R&D), Bajaj Auto Limited, Adurdi, Poona - 411 035 India; Mr. M. S. Keshav Manager (R&D) Bajaj Auto Limited Adurdi Poona - 411 035 India; Dear Mr. Keshav: This is in reply to your letter of July 7, 1981 asking for a 'exemption' from the requirement of paragraph S4.5.6 of Motor Vehicle Safety Standard No. 108 that an illuminated pilot indicator be provided in each vehicle equipped with a turn signal operating unit.; In your opinion, the front turn signal lamps mounted on the handlebar of certain motor scooters that you manufacture can serve as pilot indicators, if a front turn signal lamp fails to operate, the failure is readily apparent to the operator, if a left turn signal lamp fails, there is an 'appreciable change in the flashing rate' of the front lamp.; We concur in your interpretation. Although S4.5.6 does require th indicator, SAE Standard J588e *Turn Signal Lamps*, September 1970, incorporated by reference, requires it only if turn signal lamps are not readily visible to the driver. Because the operability of both front and rear turn signal lamps on the vehicles you described may be confirmed by the front turn signal alone, the front lamp is the functional equivalent of a turn signal indicator, and a separate indicator need not be provided.; As this is a matter of long-standing interpretation of Standard No. 10 we have no plans to amend S4.5.6 to incorporate it.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam1184OpenMr. Charles Leeds, 1775 Broadway, New York, NY 10019; Mr. Charles Leeds 1775 Broadway New York NY 10019; Dear Mr. Leeds: This is in reply to your letter of July 12, 1973, concerning th obligations of a bank under the odometer disclosure requirements of Title 49 CFR Part 580, upon its sale of a repossessed vehicle.; If upon its repossession the bank becomes the owner of the vehicle, i is required to make a disclosure statement pursuant to 49 CFR Part 580. The auctioneer does not, as a rule, obtain ownership of a vehicle and would not be required to make the disclosure statement.; Yours truly, Richard B. Dyson, 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.