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: aiam3164OpenMr. Thomas F. Brown, Executive Engineer, Mack Trucks, Inc., P.O. Box 1761, Allentown, Pennsylvania 18105; Mr. Thomas F. Brown Executive Engineer Mack Trucks Inc. P.O. Box 1761 Allentown Pennsylvania 18105; Dear Mr. Brown: I apologize for the delay in responding to your letter of June 26 1979, questioning an opinion contained in our December 12, 1978, letter to you regarding the requirements of Federal Motor Vehicles Safety Standard No. 120. Our letter stated that your company should stamp the words 'not applicable', or words of similar import, in any spaces on your certification label which are for axles not present on the vehicle to which the label is affixed. You responded that the blank spaces on the label would not be confusing, and that the likelihood of a discrepancy between the vehicle and the label is very remote.; Our letter did not address the question of the wrong label accidentall being affixed to a vehicle. Such an occurrence would mean that the vehicle would not comply with the requirements of Standard No. 120, and it could not legally be sold in the United States. Hence, any questions about a discrepancy between the information appearing on the label and the vehicle are beyond the scope of this reply.; S5.3 of Standard No. 120 requires that the labeling informatio specified in S5.3.1 - S5.3.3 appear in the format shown in the truck example following S5.3. As explained in the December 12 letter, minor variations on what is set forth in the truck example are permitted, but only is those minor variations do not change or obscure the meaning of the label. Minor variations consist of slight differences in punctuation or a substitution of words for a punctuation mark. The purpose of the labeling requirement is to clearly convey to the user of the vehicle the information specified in Standard No. 120.; Leaving blank spaces for axles which do not exist on the particula vehicle being labeled does not, upon reconsideration, change or obscure the meaning of the label. Nor is it reasonable to assume that blank spaces will confuse the average reader of the label, when those blank spaces correspond to axles not present on the vehicle. Therefore, I am hereby withdrawing the statement in our previous letter that Mack Trucks should stamp 'not applicable' or words of similar import on certification labels for axles not present on the vehicle being labeled. It would be more accurate, however, to insert these words and it would be a simple matter to do so at the same time the other variable information is applied to the label form.; Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam1661OpenMr. James B. Steward, Bridges and Collins, Bridges Building, 701 Teal Lake Avenue, Negaunee, MI 49866; Mr. James B. Steward Bridges and Collins Bridges Building 701 Teal Lake Avenue Negaunee MI 49866; Dear Mr. Steward: This is in response to your letter of October 23, 1974, commenting o the Federal law requiring execution of an odometer disclosure statement when ownership of a motor vehicle is transferred. You express concern for private individuals, who, being ignorant of the disclosure requirements, are subjected to expensive litigation in defending their failure to provide the necessary document.; The odometer requirements of the Motor Vehicle Information and Cos Savings Act were enacted in an effort to eradicate the occurrence of odometer tampering, by providing safeguards for consumers purchasing used motor vehicles which may have been subjected to an odometer alteration. In its attempt to achieve these ends, Congress ordered that an odometer disclosure statement, executed by the seller, accompany the transfer of ownership of any motor vehicle. The information required to appear on the disclosure form is considered necessary to fully inform the buyer of all facts relevant to the odometer's accuracy that may be within the seller's knowledge.; In order to protect the seller from liability where he fails to fulfil the requirements due only to a lack of knowledge of the law, the relevant provisions specify that intent to defraud must be shown in order to obtain recovery under the Act for a noncompliance.; Ignorance of the law in many situations exposes persons to unfortunat costs and burdens. However, Congress has sought, through the Cost Savings Act, to effect an improvement in the reliability of motor vehicle mileage indications. Protection of buyers from fraudulent representation of a vehicle's odometer mileage demands the enforcement of certain requirements. If a seller is ignorant of the odometer law and fails to provide a disclosure statement he will probably not be subject to liability under the Act since his inaction was not intended to defraud the buyer. Emasculating the law to remove a private seller totally from responsibility for fear he might have to defend his actions would be defeating Congress' intent.; Your suggestion that the disclosure requirements only be applied t private sellers in situations where State law requires odometer mileage disclosure to appear on the Title is unacceptable, since the Federal scheme cannot rely on a State's action for its viability.; For these reasons, we must conclude that although some private seller may incur expense in defending their failure to fully comply with the Federal odometer disclosure requirements, the disclosure provisions should continue to be applicable to all sellers of motor vehicles in order to achieve the results intended.; Yours truly, Richard B. Dyson, Acting Chief Counsel |
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ID: aiam5051OpenMr. Mark V. Schwartz Account Executive Entran Devices, Inc. 10 Washington Avenue Fairfield, NJ 07004; Mr. Mark V. Schwartz Account Executive Entran Devices Inc. 10 Washington Avenue Fairfield NJ 07004; "Dear Mr. Schwartz: This responds to your request for an interpretatio of 49 CFR Part 572, Anthropomorphic Test Dummies. Specifically, you were interested in the provisions for the Hybrid III test dummy set forth in Subpart E of Part 572. You noted that 572.36(g) provides that the thorax and knee impactor accelerometers 'shall have the dimensions and characteristics of Endevco Model 7231c or equivalent.' You provided a sheet setting forth dimensional and electrical response information for an accelerometer model produced by your company, the Entran EGE-72C-750. You then asked if the Entran EGE-72C-750 was 'equivalent' to the Endevco Model 7231c, within the meaning of 572.36(g). I am pleased to have this opportunity to explain our regulation for you. Part 572 sets forth specifications with which all test dummies must comply if those dummies are to be used in this agency's compliance testing. In NHTSA's compliance testing to date, we have used only the Endevco Model 7231c for the thorax and knee impactor accelerometers. This should not be misinterpreted as suggesting that this agency believes that only this particular make and model of accelerometer will perform acceptably in compliance testing. Instead, it means that the agency has found that the Endevco Model 7231c performs acceptably in the intended shock environment, in terms of frequency response characteristics, damping, linearity, transverse sensitivity, reliability, repeatability, durability, etc. The dictionary defines 'equivalent' as 'equal in value, measure, force, effect, significance, etc.' As noted above, NHTSA has used only the Endevco Model 7231c for the thorax and knee impactor accelerometers in the compliance testing to date. Thus, the agency has not made any determination of which accelerometers are equivalent to the Endevco Model 7231c. Until such time as the agency makes a determination about equivalent accelerometers, the issue of equivalency of your EGE-72C-750 model and the specified accelerometer model is a matter to be worked out between your company and prospective users of your company's accelerometers. As long as you can satisfy prospective users about the equivalence of your company's accelerometers, NHTSA will not review the use of any particular accelerometers in certification testing, unless the test results indicate a problem or problems caused by those accelerometers. I hope this information is helpful. If you have any further questions or need some additional information on this subject, please feel free to contact Steve Kratzke of my staff at this address or by telephone at (202) 366-2992. Sincerely, Paul Jackson Rice Chief Counsel"; |
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ID: aiam3762OpenMs. Susan Reilly, Reilly Manufacturing, P.O. Box 51, Mt. Vernon, IA 52314; Ms. Susan Reilly Reilly Manufacturing P.O. Box 51 Mt. Vernon IA 52314; Dear Ms. Reilly: This responds to your letter asking whether a motorcycle helme fastener your company produces, called 'Alpha Clip,' complies with Federal requirements.; By way of background information, this agency does not give approval of vehicles or equipment. The National Traffic and Motor Vehicle Safety Act places the responsibility on the manufacturer to ensure that its vehicles or equipment comply with applicable standards.; Safety Standard No. 218, *Motorcycle Helmets*, includes various minimu performance requirements for motorcycle helmets. The only requirement directly relevant to your fastener is the retention test, which is set forth at section S5.3. The letter you enclosed from the University of Southern California suggests that the clip passes that test.; I would note that Standard No. 218 only applies to new motorcycl helmets and not to replacement equipment for motorcycle helmets. Thus, unless your clip was sold as part of a new motorcycle helmet, the requirements of Standard No. 218 would not be directly applicable. (Please note, however, that the agency discourages helmet users from modifying their helmets. Section S5.6.1 of the standard requires that the following instruction be placed on helmets: 'Make no modifications....'); I would also note that should a safety- related defect be discovered i your device, whether by the agency or by yourself, you as the manufacturer would be required under sections 151 *et seq*. of the Act to notify owners, purchasers, and dealers and provide a remedy for the defect. These provisions apply regardless of whether the device is covered by a safety standard. A copy of the Act is enclosed.; Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam5560OpenMr. Mayo D. Tubbs Visionary Lighting Systems 1409 Sweetgum Circle Keller, TX 76248; Mr. Mayo D. Tubbs Visionary Lighting Systems 1409 Sweetgum Circle Keller TX 76248; Dear Mr. Tubbs: Thank you for providing a FAX copy of your letter o April 27, 1995, to Philip Recht. As Taylor Vinson explained to you when you phoned, the agency had no record of receiving your original letter. Our letter of April 13, 1995, to you was based upon your representation that the strip lights in your system would be 'Aviation Green'. We advised you that use of this color has the potential to create a measure of confusion rather than caution, thereby affecting the effectiveness of the mandatory side lighting equipment, i.e., amber front side markers, red rear side markers, and red and white conspicuity striping or red reflectors. You have asked whether our response would be different if the strip lamps were red or amber in color, as shown in the drawings of a van trailer in your Attachment A. In this scheme, amber lamps would be located on the side of the trailer, and red lamps on the rear. Because these colors are associated with caution, we do not believe that they would impair the effectiveness of any of a trailer's required lighting equipment. You expressed your understanding that, if the three rear identification lamps are installed at the top of a trailer, the clearance lamps can be mounted at the bottom and vice versa, as reflected in the drawings shown in your Attachment C. This is not exactly correct. Table II of Standard No. 108 requires identification lamps, without exception, to be mounted 'as close as practicable to the top of the vehicle.' While clearance lamps also are required to be 'as near the top as practicable' (Table II), when the rear identification lamps are mounted at the extreme height of the vehicle the rear clearance lamps need not be located as close as practicable to the top of the vehicle (paragraph S5.3.1.4). This configuration is reflected in the drawing on Attachment C titled 'Identification Lights on Top'. The drawing 'Identification Lights on Bottom' does not depict a location for identification lamps that conforms to Table II. Because clearance lamps are intended to indicate the overall width of the vehicle, the exception originated to accommodate trailer designs in which the widest part of the trailer was the fenders. In the van configuration shown on Attachment C, it would be practicable for both identification and clearance lamps to be mounted at the top of the trailer, and that is the location preferred by this agency for clearance lamps, notwithstanding S5.3.1.4. If there are other questions you have, Taylor Vinson will be happy to answer them for you. Sincerely, John Womack Acting Chief Counsel; |
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ID: aiam1580OpenMr. Raymond E. Jones, Project Engineer, Dura Corporation, Fords Mill Road, Paris, KY 40361; Mr. Raymond E. Jones Project Engineer Dura Corporation Fords Mill Road Paris KY 40361; Dear Mr. Jones: This responds to Dura Corporation's July 24, 1974, questions whethe S5.6 of Standard No. 121, *Air brake systems*, requires parking brakes on air suspension liftable axles, and whether the 'no lockup' requirements of the standard apply to a liftable axle on a 'tandem axle rig'.; The parking brake performance options of S5.6 do not require parkin brakes on an air suspension liftable axle such as you describe. S5.6.2 requires only that the parking brakes installed on a vehicle meet minimum performance levels. S5.6.1 requires parking brake retardation force on 'an axle other than a steerable front axle'. We do not consider this requirement to apply to an axle which is not on the ground when the parking brake system is activated.; The standard's 'no lockup' requirement (S5.3.1) applies to >>>'any wheel at speeds above 10 mph except for . . . (b) Lockup of wheels on nonsteerable axles other than the two rearmos nonliftable, nonsteerable axles on a vehicle with more than two nonsteerable axles.<<<; Under this provision, if a vehicle has two nonliftable, nonsteerabl axles at the rear which do not lock up (such as an antilock-equipped tandem axle rig) it may be equipped with a liftable nonsteerable axle which does not meet the 'no lockup' requirements.; Yours truly, Richard B. Dyson, Acting Chief Counsel. |
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ID: aiam1222OpenMr. Robert E. Gross, 2111 W. 104, Cleveland, OH 44102; Mr. Robert E. Gross 2111 W. 104 Cleveland OH 44102; Dear Mr. Gross: Your complaint to the Federal Trade Commission dated June 8, 1973, ha been referred to the National Highway Traffic Safety Administration which has responsibility for administering the Motor Vehicle Information and Cost Savings Act of 1972.; Title IV of this Act prohibits the resetting of an odometer and i requires that a seller of a motor vehicle make a written disclosure of a vehicle's mileage to the buyer prior to transfer. From your statement it appears that the vehicle's odometer had been reset and that T & J Auto Sales failed to make the required statement.; There is no criminal liability under the Act for failure to conform t these requirements but there is a civil remedy available to you as a private party. If it can be shown that T & J reset the odometer after January 18, 1973, or failed to make the required statement with intent to defraud you, they may be liable to you for $1,500 without proof of any damages or for treble damages if they are greater.; You may wish to consult an attorney in this matter. A copy of th applicable provisions of the Act and the disclosure regulation are enclosed for your information.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam4855OpenMr. Gregory J. Vonderheide Vice President Sales Markets Unlimited Group, Inc. P.O. Box 289 Conestoga, PA 17516; Mr. Gregory J. Vonderheide Vice President Sales Markets Unlimited Group Inc. P.O. Box 289 Conestoga PA 17516; Dear Mr. Vonderheide: This responds to your letter of March 6, l99l asking for the 'application(s) necessary for the Department of Transportation approval of a new product.' The product is described only as a 'Safety Light.' The Department has no authority to approve or disapprove items of motor vehicle equipment. Pursuant to the National Traffic and Motor Vehicle Safety Act, the National Highway Traffic Safety Administration establishes the Federal motor vehicle safety standards that apply to motor vehicles and/or motor vehicle equipment, and which must be met by the manufacturers of any vehicles or equipment to which the standards apply. Unless your product is intended to replace an existing light found on motor vehicles, it would not appear to be directly covered by Standard No. 108, which establishes Federal requirements for motor vehicle lighting. If indeed it is intended as an additional light, under Standard No. 108 supplementary lighting equipment is permissible as original equipment on motor vehicles provided that it does not impair the effectiveness of lighting equipment required by the standard. Supplementary lighting equipment is also permissible under the Act for vehicles in use, provided its installation by a manufacturer, distributor, dealer, or motor vehicle repair business does not render wholly or partially inoperative any element of design or device installed in accordance with any Federal motor vehicle safety standard. Without knowing more of your device, we can provide you only this general guidance. The use of equipment on bicycles is under the authority of the Consumer Product Safety Commission, 5401 Westbard Avenue, Bethesda, Md. and we are unable to advise you of their requirements. The use of supplementary lighting equipment is also regulated by the individual States. We are unable to advise you on these laws, and suggest you consult the American Association of Motor Vehicle Administrators, 4600 Wilson Boulevard, Arlington, VA 22203. Sincerely, Paul Jackson Rice Chief Counsel; |
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ID: aiam4808OpenStanley S. Zinner, Esq. Greene & Zinner, P.C. 202 Mamaroneck Avenue White Plains, NY 10601; Stanley S. Zinner Esq. Greene & Zinner P.C. 202 Mamaroneck Avenue White Plains NY 10601; "Re: FMVSS No. 123 Dear Mr. Zinner: This is in reply to your FAX lette of December 4, l990, requesting an interpretation of section S5.2.4 of 49 CFR 571.123 Motor Vehicle Safety Standard No. 123 Motorcycle Controls and Displays. Specifically, you wish an opinion 'as to the meaning, purpose, and intent' of that section. Section S5.2.4 Stands states that 'A stand shall fold rearward and upward if it contacts the ground when the motorcycle is moving forward.' As Taylor Vinson of this Office explained to you, this requirement was one of the original provisions in Standard No. 123 when it became effective in l974. However, unlike many other requirements in the standard, it was both proposed and adopted without any discussion of its meaning, purpose, and intent in the preambles to both these rulemaking actions other than the bare remark that the notices contained a requirement for stands. Furthermore, in the l6 years that the requirement has been in effect, the agency does not appear to have issued a single legal opinion relating to section S5.2.4. However, the agency has issued two interpretations of section S5.2.5 which we believe are relevant to an understanding of S5.2.4. In pertinent part, S5.2.5 Footrests states that 'Each footrest for a passenger other than an operator shall fold rearward and upward when not in use.' In a letter of February 16, l982, to American Honda Motor Co., Inc., with respect to a proposed footboard design, the then Chief Counsel commented that 'We consider that the purpose of S5.2.5 is to prevent accidents caused by rigid footrests contacting the ground in a banking turn.' In a letter of October 26, l973, also to American Honda, the then Assistant Chief Counsel commented that S5.2.5 did not require automatic folding but only the direction in which the footrests shall retract 'so that if they are inadvertently left down when not in use they will fold rearward and upward should they hit an obstacle while the motorcycle is travelling forward.' I enclose a copy of each of these letters for your information. The meaning of S5.2.4 is, we believe, clear and unambiguous: if a stand is left down, it shall fold rearward and upward if it contacts the ground (which includes the roadway) while the motorcycle is moving forward. Because both sections S5.2.4 and S5.2.5 require motorcycle equipment 'to fold rearward and upward', we further believe that the purpose and intent of both sections are the same, and that S5.2.4 could be substituted for S5.2.5 in the sentences of the two letters quoted in the preceding paragraph. I hope that this is responsive to your request. Sincerely, Paul Jackson Rice Chief Counsel Enclosures"; |
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ID: aiam0100OpenCharles S. Quarles Esq., Messrs. Quarles, Herriott, Clemons, Teschner & Noelke, 411 East Mason Street, Milwaukee, WI 53202; Charles S. Quarles Esq. Messrs. Quarles Herriott Clemons Teschner & Noelke 411 East Mason Street Milwaukee WI 53202; Dear Mr. Quarles: This is in reply to your letter of July 23 to the attention of th Federal Highway Administrator enclosing product literature on the 'Model 16' and 'Cruiser' manufactured by your client, the M-B Company. You have asked what Federal motor vehicle safety standards apply to these vehicles.; Since the Model 16 line striper is 'driven...by mechanical power' it i a 'motor vehicle' within the meaning of section 102(3) of the National Traffic and Motor Vehicle Safety Act of 1966. However, it does not fall into any of the vehicle types defined thus far, to which standards are applicable, and consequently there are no standards applicable to it at this time.; Section 255.3(b), quoted by you, defines a 'truck' as 'a motor vehicl with motive power, except a trailer, designed primarily for the transportation of property or special purpose equipment.' The definition thus excludes all trailers, but would include the Cruiser which transports special purpose equipment necessary for street sweeping. Therefore, the Cruiser must conform to all Federal standards applicable to trucks.; I hope this answers your questions. Sincerely, William Haddon, Jr., M.D., Director |
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.