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: aiam1172OpenMr. Timothy J. Kincaid, Silber, Pickus & Williams, 1505 Investment Plaza, Cleveland, OH 44114; Mr. Timothy J. Kincaid Silber Pickus & Williams 1505 Investment Plaza Cleveland OH 44114; Dear Mr. Kincaid: This is in response to your June 19, 1973, request for samples of th odometer disclosure form described in Part 580, *Odometer Disclosure Requirements*, 49 CFR S 580.6, and for the correct sequence in which to execute the mileage statement and the transfer of ownership.; The Act requires disclosure of odometer readings, but the regulation issued do not require the use of a federally-printed form, and the government therefore does not provide such forms. The use of a commercially-prepared form is satisfactory if it contains the required information, as it appears in the sample format of S 580.6. The document does not have to be separate from other transfer documents, and in the case of a transferor using a bill of sale or other transfer document, the statement may be included within the form. Either the original or a carbon copy may be given to the transferee.; Section 580.4(a) requires a transferor to furnish the statement 'Befor executing any transfer or ownership document' and include the odometer reading at the time of transfer and the date of transfer. To accomplish this, the statement must precede the transfer and should be executed on the date of transfer to reflect an accurate mileage and date. The date of the statement would then function as the date of transfer.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam4720OpenMr. Patrick S. Baran I.D.E.A. 2340 W. Belmont Chicago, IL 60618; Mr. Patrick S. Baran I.D.E.A. 2340 W. Belmont Chicago IL 60618; Dear Mr. Baran: This is in reply to your letter to Taylor Vinson o this Office, with respect to 'D.O.T. guidelines for tail light brightness' with respect to a 'brake light for the back of a motor cycle helmet.' I regret the delay in responding. The Department has no authority to 'approve' or 'disapprove' items of equipment, but we can provide guidance on the relationship of equipment to the Federal motor vehicle safety standards. I enclose a copy of a l982 interpretation with respect to a similar device, a headlamp intended for installation on a motorcycle helmet. It also represents our views with respect to your device. I enclose also a copy of SAE Standard J586c Stop Lamps, which our Rulemaking office promised you. We note that you use the term 'tail light' and 'brake light' interchangeably. In seeking State guidance you should be clear as to whether your device indicates the presence of the cyclist (taillamp), or the application of the brakes of the motorcycle (stop lamp), or both. Sincerely, Stephen P. Wood Acting Chief Counsel Enclosure; |
|
ID: aiam1522OpenMr. C. J. Kidwell, American Safety Equipment Corp., 16055 Ventura Boulevard, Encino, CA 91316; Mr. C. J. Kidwell American Safety Equipment Corp. 16055 Ventura Boulevard Encino CA 91316; Dear Mr. Kidwell: This is in reply to your letter of May 29, 1974, concerning th labeling requirements of Standard No. 218, *Motorcycle Helmets*. You ask for our 'review, comments, interpretation, recommendations, and opinions' on two test reports you had done with respect to the placement of the DOT symbol and its attachment on helmets manufactured to the standard's requirements.; The National Highway Traffic Safety Administration does not provid approval of any item of motor vehicle equipment as conforming to any motor vehicle safety standard. Each item is required to conform, and each manufacturer must determine, by methods within his discretion, whether his product conforms to a standard. With respect to the method of affixing the DOT label to the helmet, any methods that are reasonably designed to provide a label that is clearly legible for the expected life of the helmet would be satisfactory.; We would like to point out, however, that from the photograph an drawings you enclosed, it appears that the DOT symbol on your helmet is partially obscured by a goggle snap and its related material. We do not consider this obscuring of the DOT symbol to conform to the intent of the standard. Accordingly, we recommend that you either reduce the length of the snap and its related material or raise the symbol to attain complete visibility.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam3270OpenMr. Woody Fitzmaurice, Supervisor, Pupil Transportation, State of Missouri, P.O. Box 480, Jefferson City, MO 65102; Mr. Woody Fitzmaurice Supervisor Pupil Transportation State of Missouri P.O. Box 480 Jefferson City MO 65102; Dear Mr. Fitzmaurice: This responds to your recent letter asking whether the State o Missouri has authority under Federal law to specify location requirements for fuel tanks on school buses.; Section 103(d) of the National Traffic and Motor Vehicles Safety Act as amended 1974 (15 U.S.C. 1392(d)) preempts, with one exception, State motor vehicle safety standards of general applicability that are not identical to a Federal safety standard governing the same aspect of motor vehicles performance. Thus, Federal Motor Vehicle Safety Standard No. 301, *Fuel System integrity* (49 CFR 571.301), would preempt State requirements of general applicability governing the same aspect of performance as Standard No. 301. The specification of tank location in the Missouri requirements is intended to insure the integrity of the vehicle fuel system and, therefore, would be regarded by the agency as relating to the same aspect of performance as the barrier impact tests of Standard No. 301. In developing the performance requirements of the standard, the agency did not intend to regulate the location of fuel tanks.; The second sentence of section 103(d) of the Act clarifies that th limitation State safety regulations of general applicability does not prevent governmental entities from specifying additional safety features in vehicles purchased for their own use. Thus, the State of Missouri or its political subdivisions such as the Board of Education could specify additional fuel system requirements, such as tank location, in the case of public school buses, but not in the case of commercial buses. The State requirements are not permitted, however, to prevent the school bus or equipment from complying with applicable safety standards. Therefore, the school bus manufacturer would have to comply with Safety Standard No. 301 regardless of the State requirements.; I hope this has answered all of your questions. However, if you requir further information, please contact Hugh Oates of my staff (202-426-2992); Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam2898OpenMr. George I. Whiston, British Standards Institution, Head Office, 2 Park Street, London WIA 2BS; Mr. George I. Whiston British Standards Institution Head Office 2 Park Street London WIA 2BS; Dear Mr. Whiston: Please excuse the long delay in responding to your letter abou materials incorporated by reference in the Federal motor vehicle safety standards. Your primary concern is the correct version of the referenced materials to be used in conducting compliance tests if the materials are subject to change.; As you noted, Part 571.5 (CFR 571.5) of our regulations provides, i pertinent part, 'Materials subject to change are incorporated as they are in effect on the date of adoption of this part, unless the reference to them provides otherwise.' Almost all safety standards incorporating materials by reference specifically refer by month and year to a particular version of the referenced material. Therefore, the specified version should be used for compliance test purposes, even if the organization that adopted the reference material has published an updated version. If the reference does not identify a specific version, the version in effect when the safety standard was issued should be used for compliance testing.; As you pointed out, many of the voluntary industry standards do no have an 'effect date.' To determine which version was 'in effect' on the date the Federal safety standard incorporating the material was issued, the agency looks to the version adopted by the organization that developed the material as of that date. For example, the Society of Automotive Engineers Standards do not have an effective date, but they do have an identifying month and year which indicates when the latest version was approved by the appropriate SAE approval body. The agency would look at that identifying month and year to determine which version was in effect on the issuance date of the safety standard or amendment.; Regarding your request for a list of the effective dates of the Federa safety standards, please be aware that the standards are being continually amended and the new provisions have their own effective dates. Thus, there is no single effective date for each standard. The enclosed computer printout provides a listing of the effective dates of the safety standards and their amendments as of July 1978. You are correct in your assumption that the safety standards only apply to vehicles manufactured on or after the effective date of relevant standard.; Finally, the effective date of a safety standard does not have an bearing on which edition of materials incorporated by reference is applicable. The version used for compliance testing is the version specifically referred to in the standard by date or, if there is no date specification, the version which was in effect on the date of issuance of the safety standard.; If you have any further questions, I will be pleased to answer them. Sincerely, Joseph J. Levin, Jr., Chief Counsel |
|
ID: aiam2932OpenMr. Heinz W. Gerth, Mercedes-Benz, P.O. Box 350, Montvale, NJ 07645; Mr. Heinz W. Gerth Mercedes-Benz P.O. Box 350 Montvale NJ 07645; Dear Mr. Gerth:#This is in response to your letter of November 27 1978, requesting an interpretation of Federal Motor Vehicle Safety Standard No. 101-80, *Controls and Displays*. Specifically, you asked whether it is permissible to use symbols for the parking lamp functions of the headlamp switch, in addition to the headlamp symbols required in Table I of the Standard.#The answer to your question is yes. Section 5 of the standard states that each passenger car 'with any control listed in S5.1 or in column 1 of Table 1, ... shall meet the requirements of this standard for the location, identification, and illumination of such control or display.' Since no symbols or other designations are required under the standard for parking lamps where their control is not combined with that for headlamps or for 'lamps-off' positions on controls, it is up to the manufacturer whether to label these additional functions and whether to use words or symbols. Footnote 2 of Table 1 of the standard does provide that a manufacturer must use the single headlamp symbol to designate several functions when clearance, identification, parking and/or side marker lamps are all controlled with the headlamp switch. This footnote was not intended to preclude additional symbols for these other functions, however. In fact, S5.2.1 provides that 'additional words or symbols may be used at the manufacturer's discretion for the purpose of clarity.'#Regarding your drawings, clearance lamps are listed in paragraph S5.1 and in column 1 of Table 1 of the standard. Therefore, they must be identified by the symbols shown in column 3 of Table 1 or by the words 'Clearance Lamps' or 'Cl Lps'. The 'parking right and left' symbol shown on the drawing submitted with your letter would not satisfy the requirements for clearance-lamp designations. However, the symbol labeled 'Clearance Lamps' that appears on the drawings which Mr. Gebhard M. Hespeler and Mr. Craig Jones submitted on December 20, 1978, would conform with the requirements. I have enclosed a copy of that drawing.#If you have any further questions, please do not hesitate to write.#Sincerely, Joseph J. Levin, Jr., Chief Counsel; |
|
ID: aiam3620OpenMr. Harry Epstein, Kastar, Inc., Station Road at Sunrise Highway, Bellport, NY 11713; Mr. Harry Epstein Kastar Inc. Station Road at Sunrise Highway Bellport NY 11713; Dear Mr. Epstein: This responds to your letter of October 1, 1982 (and letter of Augus 31, 1982) requesting information concerning the Federal requirements applicable to auxiliary wind deflectors for passenger car doors. Your letter states that Mr. Kevin Cavey of this agency indicated that plastic wind deflectors do not have to meet any government regulations.'; We apologize, but the information given to you by Mr. Cavey wa incorrect. The National Traffic and Motor Vehicle Safety Act, as amended 1974 (the Act), authorizes the National Highway Traffic Safety Administration to issue Federal motor vehicle safety standards which are applicable to motor vehicles or motor vehicle equipment. The wind deflectors you plan to manufacture are pieces of motor vehicle equipment, and they are subject to Safety Standard No. 205, *Glazing Materials* (copy enclosed).; Incorporating by reference ANS Z26,' the American National Standard' Safety Code for Glazing Materials, Safety Standard No. 205 specifies performance requirements for various types of glazing and also the locations in vehicles in which each type of glazing may be used. Under the requirements of this standard, an auxiliary wind deflector to be used on a passenger vehicle at levels requisite for driving ability may be manufactured out of either Item 1, Item 2, Item 4, Item 10, or Item 11 glazing materials, depending upon its proposed location on the vehicle (the various types of glazing are designated as Items' in the standard). The acrylic plastic material you propose to use is probably an Item 4 glazing, which may be used as a wind deflector placed on the side window of a vehicle. An AS-4 glazing material must meet Test No. 2, Luminous Transmittance,' which requires that the material show regular (parallel) luminous transmittance of not less than 70 percent irradiation.' You will have to make the determination whether your material in fact qualifies as an Item 4 material, or any of the other Item numbers mentioned above.; Safety Standard No. 205 also sets forth specific certification an marking requirements. The requirements for prime glazing material manufacturers (those who fabricate, laminate, or temper the glazing material) are set out in paragraphs S6.1-S6.3. While not explicitly stated in your letter, it appears that you do not manufacture the glazing to be used in your deflector, but instead purchase it from a prime glazing manufacturer and then cut it yourself. If this assumption is correct, then the certification and marking requirements applicable to you are of ANS Z26, you are required under this paragraph to mark any section of glazing that you cut with the same words, designations, characters, and numerals as the piece of glazing from which it was taken. This means that you would stamp your product with markings identical to those found on the acrylic sheets you purchased. Each item must also be certified pursuant to Section 114 of the Act. Section 114 provides that an item of motor vehicle equipment may be certified by means of a label or tag on the item or on the outside of a container in which the equipment is delivered. The label or tag must state that the item of motor vehicle equipment complies with all applicable motor vehicle safety standards, which in this case would be Safety Standard No. 205.; Under Section 108(a)(1)(A) and (b)(1) of the Act, new motor vehicl equipment such as wind deflectors must comply with applicable safety standards prior to its first purchase by someone for purposes other than resale. The manufacture or installation of a wind deflector that does not conform to the standard, or the installation in a new vehicle in a location that is not provided for in Standard No. 205, would be a violation of Section 108(a)(1)(A). Under Section 109, anyone who violates Section 108(a)(1)(A) is subject to a civil penalty up to $1,000 for each violation.; Manufacturers of motor vehicle equipment also have responsibilitie under the Act regarding safety defects. Under Section 151 *et* *seq*., such manufacturers must notify purchasers about safety-related defects and remedy such defects free of charge. Again, Section 109 imposes a civil penalty of up to $1,000 upon any person who fails to provide notification of or remedy for a defect in motor vehicle equipment.; We hope you find this information helpful. Please contact Hugh Oates o this office if you have any more questions (202-426-2992).; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam2461OpenMr. Robert B. Kurre, Director of Engineering, Wayne Corporation, Industries Road, Post Office Box 1447, Richmond, IN 47374; Mr. Robert B. Kurre Director of Engineering Wayne Corporation Industries Road Post Office Box 1447 Richmond IN 47374; Dear Mr. Kurre: This is in response to your letter of November 15, 1976, in which yo ask whether emergency exits installed in school buses beyond those required in S5.2.3 of Standard No. 217, *Bus Window Retention and Release*, must meet the requirements of the standard.; The NHTSA has determined previously that only those exits required i S5.2.3 must meet the requirements specified for school bus emergency exits in Standard No. 217. All other emergency exits installed in school buses must comply with the requirements for emergency exits in buses other than school buses. These requirements are detailed in Standard No. 217.; In your letter, you ask specifically whether S5.2.3.1(b), S5.3.1 S5.3.2, S5.3.3, S5.4.1, S5.4.2.1(b) or S5.5.3 apply to a side emergency door in a school bus that already complies with S5.2.3.1(a) of the standard. The NHTSA concludes that this door would be required to comply with S5.3.1, S5.3.2, and S5.4.1 of the standard.; Sincerely, Frank A. Berndt, Acting Chief Counsel |
|
ID: aiam2031OpenMr. Jack Johnson, 8400 East Slauson Avenue, Pico Rivera, CA 90660; Mr. Jack Johnson 8400 East Slauson Avenue Pico Rivera CA 90660; Dear Mr. Johnson: This responds to Motac's August 7, 1975, request for a determinatio that two platform trailers which are designed with a primary cargo-carrying surface which is less than 40 inches above the ground would qualify for exclusion from the requirements of Standard No. 121, *Air Brake Systems*, if manufactured before September 1, 1976.; I have enclosed a copy of the amendment to Standard No. 121 whic excludes heavy hauler trailers from the requirements of the standard until September 1, 1976. You should note that the '40-inch cargo-carrying surface' criterion is measured in the unloaded condition, and that the body must not be equipped with sidewalls unless they are easily removable.; There is no requirement that the vehicle be designed for a certain typ of cargo such as heavy machinery. Therefore your semi-trailers may qualify for the exclusion if they meet the criteria listed in the definition of heavy hauler trailer.; Sincerely, James B. Gregory, Administrator |
|
ID: aiam4809OpenMr. Fred Ciampi Fred's Welding Service Route 86, Box 85 Jumping Branch, WV 25969-0085; Mr. Fred Ciampi Fred's Welding Service Route 86 Box 85 Jumping Branch WV 25969-0085; "Dear Mr. Ciampi: This responds to your letter requesting informatio concerning Federal requirements governing the manufacture of utility trailers. Your letter indicated that you plan to manufacture trailers. First, please be aware that the National Highway Traffic Safety Administration (NHTSA) has authority to issue safety standards applicable to new motor vehicles and certain items of motor vehicle equipment. For purposes of this authority, trailers are considered motor vehicles. NHTSA does not approve motor vehicles or equipment, nor does the agency endorse any commercial products. Instead, the National Traffic and Motor Vehicle Safety Act establishes a certification process under which each manufacturer must certify that its product meets agency safety standards, or other applicable standards. Periodically, NHTSA tests whether vehicles or equipment comply with these standards, and may investigate alleged safety-related product defects. The following Federal safety standards apply to trailers: Safety Standard No. 108, Lamps, Reflective Devices and Associated Equipment, Safety Standard No. 115, Vehicle identification Number--Basic Requirements, and Safety Standard No. 119, New Pneumatic Tires for Vehicles Other Than Passenger Cars. The content requirements for the vehicle identification number are found at 49 CFR Part 565. In addition, depending on the type of braking system used, trailers must meet Safety Standard No. 106, Brake Hoses, Safety Standard No. 116, Motor Vehicle Brake Fluids, and Safety Standard No. 121, Air Brake Systems. All of these standards are found in 49 CFR Part 571. In addition, as a manufacturer of motor vehicles, you would be required to submit identification information to this agency in accordance with 49 CFR Part 566, Manufacturer Identification. You would also be required to certify that each trailer complies with all applicable Federal safety standards. This certification procedure is set out in 49 CFR Part 567. You may find a copy of 49 CFR at a Federal Depository Library in your State. If you so choose, you may purchase a copy of Title 49 from the United States Government Printing Office (GPO), Washington, D.C. 20402, (202) 783-3238. With respect to laws governing trailer manufacture, the principal statute is the National Traffic and Motor Vehicle Safety Act. You may obtain a copy of this Act from GPO. You may wish to note especially 151 of the Act, which requires a manufacturer of a motor vehicle or motor vehicle equipment to conduct notice and recall campaigns if you or this agency find that your product has a safety-related defect. There may be State regulations that apply to trailer manufacture and use. In many states, a person cannot register a new vehicle unless he or she has a statement or certificate of origin. I understand that the Recreation Vehicle Industry Association will supply a small quantity of form statements or certificates upon request. You may contact that organization by writing them at 1896 Preston White Drive, Reston, VA 22090, or calling (800) 336-0154. You may wish to contact the local Department of Transportation or Motor Vehicle Administration in the states for which you have an interest for further information on state requirements. I hope you find this information helpful. Please do not hesitate to contact this office at (202) 366-2992 if you have specific questions. Sincerely, Paul Jackson Rice 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.