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
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ID: aiam0557OpenMr. Thomas S. Pieratt, Jr., Executive Secretary, Distributors Association, 602 Main Street, Cincinnati, OH 45202; Mr. Thomas S. Pieratt Jr. Executive Secretary Distributors Association 602 Main Street Cincinnati OH 45202; Dear Mr. Pieratt: This is in response to your letter of December 24, 1971, in which yo asked several questions concerning the weight rating requirements in the certification Regulations that go into effect January 1, 1972.; Your first three questions are summarized in your third question, a follows:; >>>'We are under the impression that the only way in which the GVW an GAW Ratings assigned to an Incomplete Vehicle by the Incomplete Vehicle Manufacturer can be increased would be (a) if a third axle is added, or (b) if the component parts of the existing axles are increased. Is this correct?<<<; The answer is no. The information supplied to the final-stag manufacturer by the incomplete vehicle manufacturer under Part 568 is to assist the final-stage manufacturer in completing the vehicle in conformity with the standards, and certifying in conformity with Part 567. There are no requirements, however, as to how the final-stage manufacturer uses this information. If he wishes to take it on himself to change the ratings in either direction, or to disregard the conformity information, that is his right. Of course, he will be assuming legal responsibility for whatever changes he makes, as indicated by the facts of the particular situation.; Similarly, he has the right to make whatever physical changes he wishe to the chassis, and assumes the normal responsibilities of a manufacturer in doing so. The Part 568 document offers him protection to the extent that he chooses to stay within its limits, but it is his choice to make.; You asked for a definition of 'rated cargo load' as used in the Par 567 requirement that GVWR 'shall not be less than the sum of unloaded vehicle weight, rated cargo load, and 150 pounds times the vehicle's designated seating capacity.' We have not provided a definition for this term in the regulations. By it is meant simply any figure provided to the vehicle user as to the cargo- carrying capacity, by weight, of the vehicle. There is no requirement that such a figure be provided, but if it is, it must be consistent with the gross vehicle weight rating.; Finally, you asked whether it would be 'illegal' to supply a body wit a volumetric 'capacity for holding eight tons of feed,' on a vehicle whose GVWR only allowed for a cargo load of five tons. If no rating by weight is supplied, the labeling requirement would not be violated by the volumetric capacity of the body. As we stated in a recent letter on the same question, however, such action might have adverse consequences beyond the certification regulation:; >>>[C]ompleting the vehicle so that its apparent carrying capacit exceeds the stated weight ratings may create some risks of liability beyond the certification regulations themselves. If, for example, the vehicle suffers a hazardous malfunction in use that can be traced to overloading of its axle systems, its manufacturer may be liable both under the effect provisions of the National Traffic and Motor Vehicle Safety Act (section 113, 15 U.S.C. 1402) and under common-law product liability doctrines. In such a case, the manufacturer of the incomplete vehicle might avoid liability, leaving it all on the final-stage manufacturer, by pointing out that the design of the vehicle as completed led the user to exceed the GVWR and GAWR furnished with the incomplete vehicle.' (Letter from L.R. Schneider to E. W. Mentzer, October 26, 1971, filed in Interpretations Redbook, Part 567, 568.); << |
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ID: aiam4847OpenMr. Chris Lawrence Chang & Lawrence P.O. Box 105-55 Taipei Taiwan R.O.C.; Mr. Chris Lawrence Chang & Lawrence P.O. Box 105-55 Taipei Taiwan R.O.C.; Dear Mr. Lawrence: This is in reply to your letter to Dr. Burgett o this agency. Though dated January 5, 1991, we did not receive it until March 7. With respect to your wish to produce an electronic sign board for installation in the rear window area, or on the rear, of a passenger car, I enclose a copy of an interpretation of this Office dated August 17, l989, regarding such a device. Although the interpretation is restricted to an interior-mounted electronic sign board, our conclusion would not be changed were the device to be mounted on the outside of the rear of the vehicle. In that location, and as an item of original equipment, we believe that it would impair the effectiveness of the required rear lighting equipment by its potential to distract following drivers from the signals sent by the rear lamps when they and the sign board are operated simultaneously. Although the considerations for aftermarket devices are expressed differently, as explained in the August l989 letter, the potential for distraction would appear to create a partial inoperability of the rear lamps within the meaning of the prohibition. Sincerely, Paul Jackson Rice Chief Counsel Enclosure; |
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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: aiam0804OpenMr. Charles R. Matthews, Sr. Safety Engineer, Oshkosh Truck Corporation, P. O. Box 560, Oshkosh, Wisconsin 54091; Mr. Charles R. Matthews Sr. Safety Engineer Oshkosh Truck Corporation P. O. Box 560 Oshkosh Wisconsin 54091; Dear Mr. Matthews: This is in response to your letter of July 5, 1972, requesting a opinion as to how manufacturers may take into account a vehicle's speed capability in establishing GAWR.; The Certification regulations do not specify particular speed criteri for establishing weight ratings. As a minimum, however, we believe the speed chosen should reflect the maximum speed at which it is reasonable to expect the vehicle to be driven. In the case where a vehicle is subject to some low-speed uses, such as seasonal sue as a snow plow, we believe the figure on the certification label should be based on that use of the vehicle in which its expected speed is greatest. The regulations do not provide for variable ratings based on speed.; Finally, you ask whether cautionary labels dealing with GAWR and GVW figures may be installed in the cab. The NHTSA does not object to the use of such labels. They may be used, as appropriate, to indicate permissible use of higher loads in low-speed applications.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam2839OpenMr. G. Bertella, Chief, Lighting and Optic Laboratory, Fiat- SA-GVF, Sperimentazione-Comp. Gruppi, C. Agnelli 200, 10135 Torino, Italy; Mr. G. Bertella Chief Lighting and Optic Laboratory Fiat- SA-GVF Sperimentazione-Comp. Gruppi C. Agnelli 200 10135 Torino Italy; Dear Mr. Bertella: This responds to your letter of May 8, 1978, to Mr. Vinson of thi office concerning the version of SAE J567, *Bulb Sockets*, applicable as a subreferenced standard to Federal Motor Vehicle Safety Standard No. 108.; The SAE standards which are specified in Standard No. 108 are cited b a number and letter to indicate the applicable version. These directly referenced SAE standards often subreference other SAE standards by inclusion of such terms as 'reference is made to SAE J* *' or 'reference SAE J* *' in which case, unless otherwise specified in Standard No. 108, the subreferenced standard is the version contained in the 1970 SAE Handbook (see paragraph S5.1 of Standard No. 108).; The subreferenced SAE standard closest in subject matter to J567 i J573d, *Lamp Bulbs and Sealed Units*', December 1968. By NHTSA interpretation J573 is not exclusive, and other bulb designs including tubular type bulbs are permitted which are not included in SAE J573. There is no subreferenced notation to SAE J567 contained in SAE J573d. Further, although the agency issued an interpretation in 1968 indicating that SAE Standard J575d, *Tests for Motor Vehicle Lighting Devices and Components*, August 1967, referenced J567, that statement was incorrect and J575d contains no such reference. Therefore SAE J567 is not a subreferenced standard in Standard No. 108. When an SAE Standard is not referenced or subreferenced by a Federal Standard, compliance with it is voluntary, and you may therefore use (or not use) SAE J567 or any version thereof as you choose, as long as the assembled lamp complies with Standard No. 108.; Sincerely, Joseph J. Levin, Jr., Chief Counsel |
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ID: aiam1716OpenMr. C. Henderson, Director of Engineering, American Safety Equipment Corp., 500 Library Street, San Fernando, CA 91340; Mr. C. Henderson Director of Engineering American Safety Equipment Corp. 500 Library Street San Fernando CA 91340; Dear Mr. Henderson: This is in reply to your letter of October 17,1974, requesting ou opinion on whether a torso pad you wish to utilize in a newly-designed child seating system must conform to the requirements of paragraph S4.10.1 of Standard No. 213, 'Child Seating Systems' (49 CFR S 571.213). The enclosed description, diagrams, and pictures of the pad show that it is attached directly to the harness restraint of the seating system. You suggest that because it works with the restraint webbing, it provides a cushioning function more or less like deformable, force-distributing material. You also suggest that it falls under the exclusion for belt adjustment hardware.; In our view, based on the information you provide, the torso pad is rigid component of the child seating system, and is subject to the requirements for padding and minimum radii of paragraph S4.10.1. The fact that the pad is attached to the belt system does not alter this conclusion. Paragraph S4.10.1 refers to 'any rigid component,' and the torso shield must be evaluated as a component separately from the belt system or any other component. We have determined that rigid should be interpreted in its normal, dictionary sense, and it appears from the information you have provided that the torso pad by itself is rigid in nature.; We can neither agree that because the torso pad acts as a bel adjustment system it falls within the exemption for 'belt adjustment hardware.' That exemption is intended to apply only to traditional belt adjustment hardware mechanisms, which are generally completely integrated into the belt webbing and do not protrude from it.; Yours truly, Richard B. Dyson, Acting Chief Counsel |
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ID: aiam4514OpenMr. J. Mike Callahan Precision Images P.O. Box 5524 Kent, Washington 9803l; Mr. J. Mike Callahan Precision Images P.O. Box 5524 Kent Washington 9803l; Dear Mr. Callahan: This is in reply to your letter of April l4, 1987 to Mr. Vinson of this office with respect to your representation of a company 'that will be selling plastic name plates which would be installed behind the red lens of the third brake light.' You stated that 'these are to be sold to new car dealerships. When the driver of the car steps on the brake the dealer's name lights up.' You ask for letters regarding the legality of the name plates for 24 States. We regret the delay in responding to your request. When Mr. Vinson tried to reach you by phone this week he was told that you had already received a letter, and that the answer was negative. Perhaps that letter came from one of the 24 States listed in your letter. We are unable to advise you of the legality under State laws, but I have enclosed representative interpretation letters of this agency on the legality of similar devices under Federal law. Sincerely, Erika Z. Jones Chief Counsel /; |
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ID: aiam1346OpenMr. W. H. Wendelin, Sr., Quality Control Manager, Streamline Division, 1213 West Main Street, Thorntown, IN 46701; Mr. W. H. Wendelin Sr. Quality Control Manager Streamline Division 1213 West Main Street Thorntown IN 46701; Dear Mr. Wendelin: This is in acknowledgment of your Defect Information Report, i accordance with the defect reporting regulations, Part 573.; The Defect Information Report involves: 41 - 1973 SL, Regency Imperial, and Crown Imperial Travel Trailers. Possibility that the 3/8 inch copper tube lines from the gas manifold to all appliances may have a defect thereby causing gas leakage, which may allow for a possible fire hazard.; The following National Highway Traffic Safety Administratio identification number has been assigned to the campaign *73-0224*. The first quarterly status report for this campaign is required to be submitted by February 5, 1974.; Please refer to the above number in all future correspondenc concerning this campaign.; In addition, the letter which you have sent to the first purchaser does not meet the requirements of 49 CFR Part 577 (copy enclosed) in the following respects. It does not contain the specific statements required by sections 577.4(a) and (b)(1). Your reference to a 'possible' safety hazard, moreover, is not permitted under paragraph 577.4(b)(1). We do not consider your letter to adequately describe the malfunction, as required by sections 577.4(c)(1) and (c)(2). You do not, for example, indicate the effect or possible consequence of an 'improper flare' on a gas line. Nor do you state any precautions the owner can take to reduce the likelihood of the malfunction occurring as required by 577.4(c)(4). Your letter fails completely to evaluate the risk to traffic safety as required by section 577.4(d). Finally, we consider your reference to 'no reported related failures' to be a disclaimer prohibited by section 577.6.; It is necessary for you to revise this letter as we have indicated an to provide this office and the owners with a copy of the revised letter.; Failure to comply with this regulation can result in the imposition o civil penalties and injunctive sanctions.; If you desire further information, please contact Messrs. James Murra or Marx Elliott of this office (202) 426- 2840.; Sincerely, Andrew G. Detrick, Acting Director, Office of Defect Investigation, Motor Vehicle Programs; |
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ID: aiam2993OpenMr. Michael Petler, Assistant Manager, Safety and Legislation Department, U.S. Suzuki Motor Corporation, 13767 Freeway Drive, Santa Fe Springs, California 90670; Mr. Michael Petler Assistant Manager Safety and Legislation Department U.S. Suzuki Motor Corporation 13767 Freeway Drive Santa Fe Springs California 90670; Dear Mr. Petler: This is in response to your request of March 22, 1979, for a interpretation of Federal Motor Vehicle Safety Standard No. 109. First, I would like to apologize for the delay in responding to your request of September 14, 1978. As was explained to you in a telephone conversation on March 22, your letter and the response thereto was apparently lost when the Chief Counsel's offices were moved. Although we took great care to ensure that something like this would not happen, it seemingly did in this case. I regret this and hope that it has not caused any undue inconvenience for your company.; You asked whether it was permissible under Standard 109 for manufacturer to stamp the maximum permissible inflation pressure of a tire and its maximum load rating on the tire in both English units (pounds and psi) and metric units (kilograms and kPa). S4.3(b) and (c) of the standard specify that each tire shall have permanently molded onto the sidewalls the maximum load rating for the tire. This agency has interpreted this requirement to mean that the information must appear on the sidewalls in the English units, since this is the system of measurement which will be used and understood by most consumers. However, so long as the information appears in English units, there is no reason that it could not also be the additional information does not cause confusion about the required information. By stating not only the pressure and rating values, but also the units of value, your company would avoid causing any such confusion. Therefore, the expression of inflation pressure and load rating in English and metric units as shown in your illustration is permissible under Standard 109.; Sincerely, Frank Berndt, Acting Chief Counsel |
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ID: aiam3681OpenMr. K. Inoue, National Technical Service Manager, Toyo Tire Corporation, Compton, CA 90221; Mr. K. Inoue National Technical Service Manager Toyo Tire Corporation Compton CA 90221; Dear Mr. Inoue: This responds to your February 16, 1983, letter to Joseph Innes of thi agency regarding permissible methods for displaying Uniform Tire Quality Grading (UTQG) information on the sidewall of tires. Your first proposed alternative would delete the treadwear grade number, but not the word 'TREADWEAR' itself, from the format established in Option 3 of Figure 1, 49 CFR 575.104. The second proposed alternative would delete both the word 'TREADWEAR' and the numerical grade from the format specified in Option 3, Figure 1. Your proposed alternatives would be used only on tires produced in molds manufactured before August 8, 1983.; In the agency's February 7, 1983, notice suspending the treadwea portion of the UTQGS, tires produced in molds manufactured prior to August 8 were required to display UTQG information on tire sidewalls in one of the formats specified in Figure 1 or in Figure 6 of 49 CFR 575.104. Your first proposed alternative is clearly different from each of the permitted formats. The permitted formats require either that the word 'TREADWEAR' must appear next to the treadwear grade on the tire, or neither the word nor the numerical grade must appear. Your first alternative could confuse tire purchasers, since the display format could be interpreted as attributing the grade which appears after the work (sic) 'TRACTION' to both the treadwear and traction performance of the tire. Therefore, your first proposed alternative would not be permitted under 49 CFR 575.104.; Your second proposed alternative is quite similar to one permitte format, Option 3 in Figure 6. The only difference between your second alternative and Option 3 is that the traction information is centered in the format in Option 3, while it is slightly off-center in your alternative. Your second alternative should in no way be misleading to tire purchasers, however. Further, nothing in our regulations specifies precise centering of the traction information.; Any inconsistency between your proposed format and the permitted one i so small that the agency would, as a matter of prosecutorial discretion, make no attempt to enforce the UTQGS format requirement when your second alternative is used.; If you have further questions on this matter, please contact us. Sincerely, Frank Berndt, Chief Counsel |
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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.