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 |
|---|---|
ID: nht95-6.26OpenTYPE: INTERPRETATION-NHTSA DATE: August 30, 1995 FROM: John Womack -- Acting Chief Counsel, NHTSA TO: Steven B. Fisher, Esq. -- Kostow & Daar, P. C. TITLE: Re: Motor Vehicle Safety Standard No. 108 ATTACHMT: ATTACHED TO 7/31/95 LETTER FROM STEVEN B. FISHER TO PHILLIP R. RECHT (OCC 11096) TEXT: Dear Mr. Fisher: This responds to your letter of July 31, 1995, to Philip R. Recht, formerly Chief Counsel of this agency. You have asked several questions relating to use of the word "practicable" in the lamp location requirements of Federal Motor Vehicle Safety Standard No. 108. Your first question is "with respect to truck, trailer identification lights (red), what is meant exactly by 'practicable' as used in SS5.3.1.1 and 5.3.1.4." Your second question is whose responsibility it is to make the determination of practicability. Your final question is whether there is any way for a manufacturer of "a single rear identification light" to know where a trailer manufacturer will install the product on any given trailer. We don't see the word "practicable" in S5.3.1.1. However, S5.3.1.4 does provide that rear clearance lamps need not meet the requirement of Table II that they "be located as close as practicable to the top of the vehicle" when the rear identification lamps are located at the extreme height of the vehicle. Table II specifies location of lighting equipment on the vehicle, and it is therefore the responsibility of the vehicle manufacturer, in certifying that its vehicle complies with all applicable Federal motor vehicle safety standards, to determine what is practicable. As you indicate, a trailer manufacturer may make such a determination "in light of the particular design/configuration of the trailer involved." NHTSA will not contest this determination unless it is clearly erroneous. In short, "practicable" as meant by S5.3.1.4 or any other place where the word occurs, is not a term defined by Standard No. 108, and derives its meaning from specific factual contexts. We note that the Random House Dictionary of the English Language (1967) defines "practicable" as "capable of being done, effected, or put into practice with the available means" (p. 1127). There is no responsibility under Standard No. 108 for the manufacturer of identification lamps to know where its products will be installed on the motor vehicle. Its responsibility under Standard No. 108 is to ensure that any identification lamp that it manufactures for replacement purposes is designed to conform to Standard No. 108's performance specifications and so certified at the time the lamp is shipped from the factory. If you have any further questions you may phone Taylor Vinson of this office (202-366-5263). |
|
ID: nht95-4.4OpenTYPE: INTERPRETATION-NHTSA DATE: August 30, 1995 FROM: John Womack -- Acting Chief Counsel, NHTSA TO: Steven B. Fisher, Esq. -- Kostow & Daar, P. C. TITLE: Re: Motor Vehicle Safety Standard No. 108 ATTACHMT: ATTACHED TO 7/31/95 LETTER FROM STEVEN B. FISHER TO PHILLIP R. RECHT (OCC 11096) TEXT: Dear Mr. Fisher: This responds to your letter of July 31, 1995, to Philip R. Recht, formerly Chief Counsel of this agency. You have asked several questions relating to use of the word "practicable" in the lamp location requirements of Federal Motor Vehicle Safety Standa rd No. 108. Your first question is "with respect to truck, trailer identification lights (red), what is meant exactly by 'practicable' as used in SS5.3.1.1 and 5.3.1.4." Your second question is whose responsibility it is to make the determination of practicability. Your final question is whether there is any way for a manufacturer of "a single rear identification light" to know where a trailer manufacturer will install the product on any given trailer. We don't see the word "practicable" in S5.3.1.1. However, S5.3.1.4 does provide that rear clearance lamps need not meet the requirement of Table II that they "be located as close as practicable to the top of the vehicle" when the rear identification lam ps are located at the extreme height of the vehicle. Table II specifies location of lighting equipment on the vehicle, and it is therefore the responsibility of the vehicle manufacturer, in certifying that its vehicle complies with all applicable Federa l motor vehicle safety standards, to determine what is practicable. As you indicate, a trailer manufacturer may make such a determination "in light of the particular design/configuration of the trailer involved." NHTSA will not contest this determinatio n unless it is clearly erroneous. In short, "practicable" as meant by S5.3.1.4 or any other place where the word occurs, is not a term defined by Standard No. 108, and derives its meaning from specific factual contexts. We note that the Random House Di ctionary of the English Language (1967) defines "practicable" as "capable of being done, effected, or put into practice with the available means" (p. 1127). There is no responsibility under Standard No. 108 for the manufacturer of identification lamps to know where its products will be installed on the motor vehicle. Its responsibility under Standard No. 108 is to ensure that any identification lamp that it manufactures for replacement purposes is designed to conform to Standard No. 108's performance specifications and so certified at the time the lamp is shipped from the factory. If you have any further questions you may phone Taylor Vinson of this office (202-366-5263). |
|
ID: 1096Open Steven B. Fisher, Esq. Re: Motor Vehicle Safety Standard No. 108 Dear Mr. Fisher: This responds to your letter of July 31, 1995, to Philip R. Recht, formerly Chief Counsel of this agency. You have asked several questions relating to use of the word "practicable" in the lamp location requirements of Federal Motor Vehicle Safety Standard No. 108. Your first question is "with respect to truck, trailer identification lights (red), what is meant exactly by `practicable' as used in SS5.3.1.1 and 5.3.1.4." Your second question is whose responsibility it is to make the determination of practicability. Your final question is whether there is any way for a manufacturer of "a single rear identification light" to know where a trailer manufacturer will install the product on any given trailer. We don't see the word "practicable" in S5.3.1.1. However, S5.3.1.4 does provide that rear clearance lamps need not meet the requirement of Table II that they "be located as close as practicable to the top of the vehicle" when the rear identification lamps are located at the extreme height of the vehicle. Table II specifies location of lighting equipment on the vehicle, and it is therefore the responsibility of the vehicle manufacturer, in certifying that its vehicle complies with all applicable Federal motor vehicle safety standards, to determine what is practicable. As you indicate, a trailer manufacturer may make such a determination "in light of the particular design/configuration of the trailer involved." NHTSA will not contest this determination unless it is clearly erroneous. In short, "practicable" as meant by S5.3.1.4 or any other place where the word occurs, is not a term defined by Standard No. 108, and derives its meaning from specific factual contexts. We note that the Random House Dictionary of the English Language (1967) defines "practicable" as "capable of being done, effected, or put into practice with the available means" (p. 1127). There is no responsibility under Standard No. 108 for the manufacturer of identification lamps to know where its products will be installed on the motor vehicle. Its responsibility under Standard No. 108 is to ensure that any identification lamp that it manufactures for replacement purposes is designed to conform to Standard No. 108's performance specifications and so certified at the time the lamp is shipped from the factory. If you have any further questions you may phone Taylor Vinson of this office (202-366-5263). Sincerely,
John Womack Acting Chief Counsel ref:108 d:8/30/95
|
1995 |
ID: 11986.ZTVOpen Herr Sandig Dear Herr Sandig: This replies to your FAX of May 28, 1996, asking whether a proposed design for a center highmounted stop lamp is a single lamp, within the meaning of Federal Motor Vehicle Safety Standard No. 108. In this design, a rectangular lens is separated by an opaque oval that covers the center portion of the lens. However, the sum of the effective projected luminous lens areas left uncovered exceeds the minimum 4.5 square inches required by paragraph S5.1.1.27(a)(1) of Standard No. 108. This design does not comply with Standard No. 108. Paragraph S5.1.1.27 (a) requires vehicles to be equipped with "a high-mounted stop lamp." Table IV requires the lamp to be located "on the vertical centerline." The opaque area in your design functionally divides the center lamp into two lamps, neither of which is located on the vertical centerline. In the past, the agency has advised that the lens of the center stop lamp may be obscured to a certain extent by decals or other trim, provided the minimum luminous lens area requirement was met, and the obscuration did not affect photometric compliance. These interpretations always assumed that the appearance of a single lamp would be maintained, even though the lens area itself did not present an uninterrupted light-emitting surface. Paragraph S5.1.1.27(b) does allow two separate lamps on vehicles other than passenger cars when there is insufficient space above doors opening from the center, but your lamp is not designed to address this problem. If you have any questions, you may refer them to Taylor Vinson of this Office. Sincerely, Samuel J. Dubbin Chief Counsel ref:108 d:6/14/96 |
1996 |
ID: 06-005423asOpenMr. Kiminori Hyodo Deputy General Manager, Regulation & Certification Koito Manufacturing Co., Ltd. 4-8-3, Takanawa Minato-Ku Tokyo Japan Dear Mr. Hyodo: This responds to your letter requesting clarification regarding the luminous intensity requirements for front turn signal lamps under Federal Motor Vehicle Safety Standard No. 108, Lamps, Reflective Devices, and Associated Equipment (FMVSS No. 108). Specifically, you asked whether the multiplier in paragraph S5.3.1.7 of Standard No. 108 applies to the minimum luminous intensities listed in Figure 20, Visibility of Installed Lighting Devices (Luminous Intensity Measurement Method). As discussed below, it does not. By way of background, the National Highway Traffic Safety Administration (NHTSA) is authorized to issue FMVSSs that set performance requirements for new motor vehicles and items of motor vehicle equipment (see 49 U.S.C. Chapter 301). On August 11, 2004, NHTSA published a final rule updating FMVSS No. 108 to increase compatibility with the relevant standards of the Society of Automotive Engineers (SAE) and the Economic Commission for Europe (ECE) pertaining to a variety of lighting requirements (see 69 FR 48805). The luminous intensity multiplier referred to in paragraph S5.3.1.7 of Standard No. 108 applies to the photometric requirements of turn signal lamps. Paragraph S5.3.1.7 specifies that the multiplier applied to obtain the required minimum luminous intensities shall be 2.5. The multiplier referred to in paragraph S5.3.1.7 supersedes the luminous intensity multiplier described in paragraph 5.1.5.4 of SAE J588 (rev. Nov. 84), which has been incorporated by reference into FMVSS No. 108 via paragraph S5.1.1 and Table III of the standard. (S5.1.1 refers to Table III, which references SAE J588 (rev. Nov. 84) as the applicable standard for turn signal lamps.) To explain more fully, paragraph 5.1.5.4 of SAE J588 (rev. Nov. 84) specifies numerous luminous intensity multipliers dependent on the lamp separation distance. Paragraph S5.3.1.7 overrides this SAE specification by requiring that turn signal lamps mounted within 100mm of the lighted edge of a headlamp shall use 2.5 as the multiplier. Thus, the luminous intensity multiplier referred to in FMVSS No. 108 paragraph S5.3.1.7 applies to the SAE J588 (rev. Nov. 84) photometric requirements of turn signal lamps. We note that the minimum luminous intensities referred to in Figure 20 of FMVSS No. 108 are visibility requirements, not photometric requirements. The origin of these requirements is FMVSS No. 108 paragraph S5.3.2(b). This paragraph states that a manufacturer must certify compliance of each lamp to one of the following visibility requirement options, with one option being that each such lamp must provide a luminous intensity not less than that specified in Figure 20. Because this refers to visibility requirements, referencing the light seen by the human eye, as opposed to photometry requirements, referencing the output of light from the lamp (and which was the subject of the luminous intensity multiplier), the multiplier does not apply to the values in Figure 20. I hope this information is helpful. If you have any further questions, please contact Ari Scott of my staff at (202) 366-2992. Sincerely, Anthony M. Cooke Chief Counsel ref:108 d.2/7/07 |
2007 |
ID: nht90-1.25OpenTYPE: INTERPRETATION-NHTSA DATE: JANUARY 26, 1990 FROM: KENT D. SMITH TO: OFFICE CHIEF COUNCIL -- NHTSA TITLE: NONE ATTACHMT: ATTACHED TO LETTER DATED 3-22-90 TO KENT D. SMITH FROM STEPHEN P. WOOD, NHTSA; [REDBOOK A35; STD. 108] TEXT: I recently submitted an invention on a safety device to the Office of Crash Avoidance Research in the U.S. Department of Transportation. William A. Leasure, Jr., the Director of this office, responded to my letter but referred me to your office because there were some legal questions involved. I believe that vehicles need some way of signaling following drivers if the headlamps of their vehicles are blinding you. I am a Driver Education teacher and whenever my students confront me with this problem there is no solution that up to now is ef fective. My invention, which is designed to deal with this problem is this: A button on the dashboard is attached to the backup lights. When the button is pushed the backup lights will go on and off in a matter of a second or less. The lights would not come back on again unless the button was pressed a second time. If necessary the button could be hooked up to only one of the backup lights. This would eliminate any confusion on the part of the driver of the following vehicle as to which direction th e car may be going. An alternative could be to hook the button up to the license plate lights. If this were done a double filament light would have to be installed so that the increase in intensity would be immediately observable by the driver of the f ollowing vehicle. This method of installation would not violate the SAE Standard for backup lights but I dont feel that it would be as effective as having the backup lights momentarily activated. I firmly believe that this new innovative concept would give the driver an effective means of informing the driver of the following vehicle that you were being blinded by his inconsiderate action. I'm aware of the Federal law that states that the backup lights should not be on when the car is going in a forward direction. I believe that the intent of the law is to force people to make repairs so that those lights will not stay on and therby co nfuse people into thinking that the car is backing up rather than going forward. It would seem to me that this new concept could be added to an automobile without violating the intent of the federal law concerning backup lights. I explained my idea to a gentleman from the Utah Department of Public Safety. He felt the idea was good enough that it should be pursued even if it meant making a revision in the Federal law that governed backup lights. Would you please offer me any recommendations, either positive or negative, in regards to this invention. I thank you for your time and look forward to hearing from you in the very near future. Please send your reply to: Kent D. Smith 12249 S. 1565 E. Draper Utah 84020 |
|
ID: nht69-2.27OpenDATE: 10/03/69 FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA TO: Harbors Trailers Inc. TITLE: FMVSR INTERPRETATION TEXT: This is in response to your letters of August 12 and September 4, 1969 in which you asked several questions about the responsibilities under the National Traffic and Motor Vehicle Safety Act of companies that assemble bodies to chassis. I have taken the liberty of restating your questions. What does a person who assembles truck bodies to chassis certify, and on what basis: Such an assembler is a manufacturer" under the Act, and the vehicles that he assembles must be certified by him as conforming to all applicable standards. The primary responsibility for conformity of the chassis-cab, however, falls on the manufacturer of it (generally a major automotive manufacturer), and under the regulations that manufacturer is required to affix to label to the chassis-cab listing the standards to which it conforms. Under section 108(b)(2) of the Act, such a certification protects subsequent persols in the chain of distribution from liability from noncenformity of while they have no knowledge. Thus, the body assembler is directly responsible for conformity of the finished vehicle with (1) any applicable standard to which the chassis-cab manufacturer has not certified, and (2) any other standards conformity to which is affected by what the assembler does to the vehicle. His certification must be for all standards, in the language specified in the certification regulations, but he can rely on the interim certification of the chassis-cab manufacturer for the standards it covers, as long as he does not know of any nonconformity. What are the applicable standards? The applicable standards for a vehicle manufactured by assembling a body to a chassis-cab are those in effect on the date on which the chassis-cab was completed. This date appears on the label that the chassis-cab manufacturer must affix to the chassis-cab. What is the vehicle identification number that must appear on the assembler certification label? At present there is not a safety standard relative to a vehicle identification number for vehicles other than passenger cars. The vehicle identification number to be affixed to the completed vehicle under the certification regulations, therefore, should be a number assigned to the vehicle by the assembler, by which he can identify the vehicle on request of an investigating agency such as the Federal Highway Administration. Is there any requirement for certification of truck bodies separately from the assembled vehicles? No. A truck body is not a "motor vehicle" within the meaning of the Act and the regulations, and therefore is not covered by the present Certification Regulations (49 CFR Part 367). Although it is "motor vehicle equipment", such equipment is only required by the Act to be certified where there is a safety standard applicable directly to it; and there are none at present for truck bodies. When the body is assembled to the chassis, the completed vehicle must be certified in accordance with the Certification Regulations, as explained above. I am enclosing a copy of the current standards and regulations. We are pleased to be of assistance. |
|
ID: nht95-2.87OpenTYPE: INTERPRETATION-NHTSA DATE: May 19, 1995 FROM: Don Bearden -- Director, Governmental Affairs TO: John Womack -- Acting Chief Counsel, NHTSA TITLE: Interpretation of 49 CFR Part 581, Bumper Standard ATTACHMT: ATTACHED TO 6/9/95 LETTER FROM JOHN WOMACK TO DON BEARDEN (A43; PART 581) TEXT: Dear Mr. Womack: Subaru of America, Inc. is considering the use of an optional rear bumper-mounted spare tire carrier on a future vehicle as shown on the attached sketch. All trim levels of this vehicle would be offered both with and without the optional rear spare t ire carrier. (For vehicles without the optional external carrier, the spare tire would be carried inside the vehicle). At this time, we can only estimate the sales appeal of this option, but project that it will be specified for far less than 50% of th e car line. The bumper test conditions contained in 49 CFR @ 581.6(5) specify that "[running] lights, fog lamps, and equipment mounted on the bumper face bar are removed from the vehicle if they are optional equipment." (Emphasis added.) Since the Subaru optional spare tire carrier would be mounted to the bumper beam and face bar, we understand that the tire and carrier would be removed from the vehicle prior to the conducting of the Part 581 bumper test. We would appreciate your confirmation of our interpretation. Thank you for your assistance. Should you or your staff have any questions concerning this request, please contact me at (609) 488-8644 Enclosure Rear spare tire carrier without equipment with equipment (Graphics omitted.) |
|
ID: nht68-2.31OpenDATE: 11/26/68 FROM: R. M. O'Mahoney -- A'SST. CHIEF COUNSEL, NHTSA; SIGNATURE BY LAWRENCE R. SCHNEIDER TO: A.J.J. Enterprises Inc. TITLE: FMVSR INTERPRETATION TEXT: The Department of Health, Education, and Welfare has forwarded your letter of October 11 for further reply. You ask for information as to how you may import a Daihstsu beach buggy "with a total weight of 960 pounds" under the National Traffic and Motor Vehicle Safety Act of 1966. Since, generally, a dune buggy is constructed "with special features for occasional off-road operation" it is classified as a "multipurpose passenger vehicle" under the Federal motor vehicle safety standards. The standards, however, do not currently apply to multipurpose passenger vehicles with a curb weight of 1,000 pounds or less. Curb weight means the weight of the vehicle with standard equipment, maximum capacity of engine fuel, oil, and coolant; and, if so equipped, air conditioning and additional weight optional engine. While I do not know the capacity of the planned fuel tank, I understand that one gallon of gas weighs 5-6 1/2 pounds. If your overall weight figure of 960 pounds is the curb weight, or if the curb weight is 1,000 pounds or less the vehicle may be imported as one manufactured prior to a date applicable Federal standards were in effect. If the curb weight is over 1,000 pounds then the vehicle, if it has not been manufactured to conform, may be imported upon an undertaking to bring it into conformity within 90 days. I enclose a copy of the importation regulations for your guidance, and should you require a copy of standards applicable to multupurpose passenger vehicles, will supply it on your request.
|
|
ID: nht78-3.50OpenDATE: 03/14/78 FROM: AUTHOR UNAVAILABLE; John Womack; NHTSA TO: Rohm and Haas Company TITLE: FMVSR INTERPRETATION TEXT: This is in response to your letter of January 27, 1978, requesting that the National Highway Traffic Safety Administration review the draft of the form with which you propose to satisfy the Federal odometer requirements. The form you are proposing to use differs from the Federal form in that the two sets of certifications are combined into an introductory certification with four exceptions. The regulations require the transferor to certify that the odometer reading reflects the actual mileage, reflects the mileage over 99,999 miles, or is not actual. Your form would allow a transferor to execute a disclosure statement without making any of the above certifications. The introductory statement says "if none of the exception block(s) below is checked, the Seller hereby certifies. . . ." Therefore, by checking the third or fourth box the transferor would be indicating that the exception applies but neither of the introductory statements applies. For this reason we cannot give our approval to use this form as the Federal disclosure form. |
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.