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: nht95-4.68OpenTYPE: INTERPRETATION-NHTSA DATE: October 30, 1995 FROM: John Womack -- Acting Chief Counsel, NHTSA TO: Larry W. Strawhorn -- Vice President of Engineering, American Trucking Associations TITLE: NONE ATTACHMT: ATTACHED TO 9/6/95 LETTER FROM LARRY W. STRAWHORN AND EARL EISNHART TO JOHN G. WOMACK TEXT: Dear Mr. Strawhorn: This letter responds to your request for an interpretation of the antilock malfunction indicator requirements set forth at S5.2.3.3 of Standard No. 121, Air Brake Systems. This provision explains the situations in which the trailer lamp malfunction indic ator must remain activated. Section S5.2.3.3 reads as follows: S5.2.3.3 Antilock Malfunction Indicator. Each trailer (including a trailer converter dolly) manufactured on or after March 1, 1998 and before March 1, 2006 shall be equipped with a lamp indicating a malfunction of a trailer's antilock brake system. Such a lamp shall remain activated as long as the malfunction exists whenever the power is supplied to the antilock brake system. The display shall be visible within the driver's forward field of view through the rearview mirror(s), and shall be visible once the malfunction is present and power is provided to the system. (Emphasis added.). In particular, you request that the agency confirm your belief that the lamp activation pattern for trailers may be such that the bulb be ON when the antilock system is working properly and OFF when a malfunction exists, the antilock system is not gettin g electrical power, or the lamp bulb is burnt out. You contended that such an activation pattern provides a fail safe pattern i.e., it will signal an inoperative antilock system even when the system is not receiving electrical power or the lamp bulb is b urnt out. NHTSA disagrees with your suggested reading of the malfunction indicator requirements. Such a reading would be inconsistent with S5.2.3.3's language stating that the lamp must "remain activated as long as the malfunction exists whenever the power is sup plied to the antilock brake system." As with other malfunction indicators, the agency intends the malfunction indicator to activate when a malfunction exists and not activate when the system is functioning properly. To require otherwise would be inconsi stent with our requirements for other indicators and thus would create confusion. Please note that NHTSA provided a lengthy discussion about the issue of a malfunction indicator's activation protocol in the March 10, 1995 final rule. (60 FR 13216, 1324 6) The agency stated that in response to an ABS malfunction, a trailer or tractor indicator must activate and provide a continuous yellow signal. The agency explained that such a common indicator pattern standardizes the activation format, thus reducing ambiguity and confusion and expediting Federal and State inspections. I hope this information has been helpful. If you have any other questions, please contact Marvin Shaw of my staff at this address or by phone at (202) 366-2992. |
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ID: nht95-4.69OpenTYPE: INTERPRETATION-NHTSA DATE: November 7, 1995 FROM: Samuel J. Dubbin -- Chief Counsel, NHTSA TO: James J. Gregorio TITLE: NONE ATTACHMT: Attached to 9.23.95 letter from James J. Gregorio to John Womack TEXT: Dear Mr. Gregorio: This responds to your letter of September 23, 1995, requesting" authorization to modify the car seat in my 1992 Plymouth Acclaim." Your letter states: Presently, my car is equipped with hand controls which alleviates a condition of chronic tendinitis in my right ankle. Unfortunately, there is practically no room between the hand controls and my knees. My knees constantly bang up against the hand c ontrols. The resulting consequence is that I now have tendinitis in both knees. Modifying the car seat will allow me to push the car seat back far enough to give space to my injured knees. You enclosed a letter from your physician stating that recovery could take several years. In summary, our answer is that you may have your vehicle modified. NHTSA will not institute enforcement proceedings against a repair business that modifies the seat on your vehicle to accomodate your condition. A more detailed answer to your letter is provided below. I would like to begin by noting that repair businesses are permitted to modify vehicles without obtaining permission from NHTSA to do so, but are subject to certain regulatory limits on the type of modifications they may make. In certain limited situati ons, we have exercised our discretion in enforcing our requirements to provide some allowances to a repair business which cannot conform to our requirements when making modifications to accommodate the special needs of persons with disabilities. Since y our situation is among those given special consideration by NHTSA, this letter should provide you with the relief you seek. Our agency is authorized to issue Federal Motor Vehicle Safety Standards (FMVSS) that set performance requirements for new motor vehicles and items of motor vehicle equipment. Manufacturers are required to certify that their products conform to our safe ty standards before they can be offered for sale. Manufacturers, distributors, dealers, and repair businesses are prohibited from "knowingly making inoperative" any device or element of design installed on or in a motor vehicle in compliance with an appl icable FMVSS. Violations of this prohibition are punishable by civil fines up to $ 1,000 per violation. Moving a seat, and presumably moving the seat belts for the seat, could affect compliance with four safety standards: Standard No. 207, Seating Systems, Standart No. 208, Occupant Crash Protection, Standard No. 209, Seat Belt Assemblies, and Standard No. 210, Seat Belt Assembly Anchorages. Your letter does not provide any information regarding why the modification to your seat cannot be done in a way that would not violate the make inoperative prohibition. However, in situations such as your where a vehicle must be modified to accommodate the needs of a particular disability, we have been willing to consider any violations of the "make inoperative" prohibition a purely technical one justified by public nee d. As I have already noted above, NHTSA will not institute enforcement proceedings against a repair business that modifies the seat on your vehicle to accommodate your condition. We caution, however, that only necessary modifications should be made to the seat, and the person making the modifications should consider the possible safety consequences of the modifications. For example, in moving a seat, it is critical that the modi fier ensure that the seat is solidly anchored in its new location. You should also be aware that an occupant of a seat which has been moved rearward may have less protection in a crash if the seat is too far rearward relative to the anchorages of the sa fety belts for that seat. Finally, if you sell your vehicle, we encourage you to advise the purchaser of the modifications. I hope this information has been helpful. If you have any other questions or need some additional information in this area, please contact Mary Versailles of my staff at this address or by phone at (202) 366-2992. |
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ID: nht95-4.7OpenTYPE: INTERPRETATION-NHTSA DATE: August 30, 1995 FROM: John Womack -- Acting Chief Counsel, NHTSA TO: Paul Jackson Rice, Esquire -- Arent Fox TITLE: NONE ATTACHMT: ATTACHED TO 08/30/95 LETTER FROM PAUL JACKSON RICE TO JOHN WOMACK TEXT: Dear Mr. Rice: This responds to your letter of August 30, 1995, concerning a June 6, 1995 letter from this office to C. Rufus Pennington, III. You asked us to confirm that the agency did not take a position as to whether there are "designated seating positions" in the rear of the 1979 911 SC Porsche. You are correct. As the letter clearly states, "NHTSA cannot make a determination as to whether a vehicle complied with applicable safety standards outside a compliance proceeding. I hope this information has been helpful. |
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ID: nht95-4.70OpenTYPE: INTERPRETATION-NHTSA DATE: November 8, 1995 FROM: Jane Thornton Mastrucci -- Thornton, Mastrucci and Sinclair TO: John Womack -- Chief Counsel, NHTSA TITLE: NONE ATTACHMT: 12/26/95 letter from Samuel J. Dubbin (signed by John Womack) to Jane Thornton Mastrucci (A43; Part 571.3; VSA 102) TEXT: We represent the Dade County School Board with respect to its vehicular litigation. The Florida Legislature has just passed a new law, F.S. 234.02 (1)(a) which allows a School Board to use, in addition to passenger cars not exceeding eight students, any other motor vehicle designed to transport ten on fewer persons which meets all fe deral motor vehicle safety standards for passenger cars. Similarly, the Department of Education Rule 6A-3.017 (10)(c) allows the transportation of students, when necessary or practical, in multipurpose vehicles, providing the MPV meets all of the applica ble passenger car federal motor vehicle safety standards, except the standard pertaining to window tinting. Copies of both of these statutes are attached. Would you please advise which passenger vehicles which multipurpose vehicles meet all federal motor safety standards. Thanking you for your courtesy and cooperation in advance, I remain, Florida statutes are omitted. |
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ID: nht95-4.71OpenTYPE: INTERPRETATION-NHTSA DATE: November 8, 1995 FROM: Linda Stroud -- Executive Officer, Used Motor Vehicle and Parts Commission, Louisiana Dept. of Economic Development TO: Walter K. Myers, -- Attorney-Advisor, Office of the Chief Counsel, NHTSA TITLE: NONE ATTACHMT: 2/15/96 letter from Samuel J. Dubbin to Linda Stroud (A44; Std. 120) TEXT: We have spoken several times in the past month regarding the sale of new trailers with used tires. I am requesting that you confirm the following information in writing to insure that I am understanding you correctly. The information you have given me regarding these sales is that a dealer shall not sell a new trailer with used tires, he can sell with either new tires or no tires. In our conversation on November 6th, I expressed the concerns of this agency and our Louisiana dealers in the compliance of this regulation. The main problem appears to exist with the manufacturer who is shipping new trailers with used tires. You infor med me that in an instance such as this, the dealer would have to remove the used tires prior to the retail sale. When the retail sale occurred, in order for the customer to remove the trailer he would have to supply his own tires or purchase tires. In addition, the dealer could not put these tires on the trailer, the customer must perform the task himself. I am also in need of answers to the following questions: 1. What is the definition of a trailer manufacturer? 2. Is a Utility Trailer included in this safety standard or does it relate only to certain size trailers? 3. Could you indicate those trailers which are governed by this regulation? 4. Is there a specific length or width that falls under this safety standard? Thank you for your cooperation and assistance in this matter and I await your immediate response. |
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ID: nht95-4.72OpenTYPE: INTERPRETATION-NHTSA DATE: November 9, 1995 FROM: Samuel J. Dubbin -- Chief Counsel, NHTSA TO: Randall Townley -- Statewide Coordinator, The University of Georgia, Cooperative Extension Service TITLE: NONE ATTACHMT: 8/8/95 letter from Randall Townley to Office of Chief Council, NHTSA (OCC 11181) TEXT: This responds to your letter of August 8, 1995. Your letter states that you are aware that side-facing bench seats are installed in some vehicles. You asked for an opinion about this issue. By way of background information, the National Highway Traffic Safety Administration (NHTSA) is authorized to issue Federal Motor Vehicle Safety Standards that set performance requirements for new motor vehicles and items of motor vehicle equipment. NHT SA does not approve or certify any vehicles or items of equipment. Instead, each manufacturer is responsible for "self-certifying" that its products meet all applicable safety standards. NHTSA has issued only one regulation that would prohibit side-facing seats. Standard No. 222, School Bus Passenger Seating and Crash Protection, requires passenger seats in school buses to be forward-facing. For all other seats in various vehicles, NHTS A's regulations neither prohibit nor require any orientation. Therefore, any orientation is permitted provided that the seat and vehicle comply with all applicable standards. I hope this information has been helpful. If you have other questions or need some additional information, please contact Mary Versailles of my staff at this address or by phone at (202) 366-2992. |
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ID: nht95-4.73OpenTYPE: INTERPRETATION-NHTSA DATE: November 13, 1995 FROM: David T. Zelis -- Marketing Manager, Buyers Products Company TO: Office Of Chief Counsel -- NHTSA TITLE: NONE ATTACHMT: 12/22/95 letter from Samuel J. Dubbin to David T. Zelis (A43; Part 581) TEXT: Enclosed please find a copy of literature describing a new product from our company. The Pintle Mount Bumper basically is designed to take the place of a vehicle bumper and the receiver tube assembly on a light duty truck. Would you please send a copy of NHTSA standards that may apply to the use or manufacture of this product. Please feel free to contact me with any questions, at (216) 974-8888. Thank you for your assistance. (Literature omitted.) |
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ID: nht95-4.74OpenTYPE: INTERPRETATION-NHTSA DATE: November 13, 1995 FROM: Tommy Reeder -- Loadcraft Manufacturing Corp. TO: Dave Coleman -- NHTSA TITLE: Lights on Rear of Trailer ATTACHMT: 1/29/96 letter from Samuel J. Dubbin to Tommy Reeder (A44; Std. 108) TEXT: WE HAVE A TRAILER CURRENTLY IN PRODUCTION THAT IS CAUSING A CONCERN ITS ORIGINAL APPLICATION WAS FOR FARM IMPLEMENTS WE NOW HAVE A CUSTOMER USING IT FOR SHIPPING CONTAINERS. IT HAS A TILT DECK -- BECAUSE OF THIS, LIGHTS ON THE EXTREME END TEND TO BE CRU SHED BY ROCKS OR MUD WHEN THE TRAILER DECK IS TILTED TO WINCH SOMETHING ON THE DECK. THE FARM TRAILER USED LIGHTS MOUNTED ON THE FURTHER MOST CROSSMEMBER FACING THE REAR OF TRAILER. DO THE LIGHTS HAVE TO BE AT THE VERY END OF THE TRAILER? WE HAVE STARTED USING A DROP BAR IN ADDITION TO THE LIGHTS ON THE CROSSMEMBER TO INCREASE VISIBILITY OF THE TAIL LIGHTS IN TRAFFIC, -- IS THIS ACCEPTABLE? Drawing omitted. |
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ID: nht95-4.75OpenTYPE: INTERPRETATION-NHTSA DATE: November 13, 1995 FROM: B. Michael Korte, Esq. -- Law Firm of John B. Schwabe II TO: NHTSA TITLE: Airbag Safety ATTACHMT: 1/29/96 letter from Samuel J. Dubbin to B. Michael Korte (A44; Std. 208) TEXT: To Whom It May Concern: I am a lawyer in St. Louis, Missouri who represents a client who injured in a rearend collision with another driver. The other driver's airbag deployed, but the other driver claims that she was travelling less than 15 miles per hour at impact. I have, as best as I can, reviewed 49 CFR 571.208 and other sections of the Code of Federal Regulations regarding federal standards as to the deployment of airbags. After doing so, however, I am unable to determine whether or not any federal standard s exist as to the deployment of airbags. In other words, I am unable to determine whether or not federal regulations establish a minimum speed that vehicles must be travelling, below which an airbag will not deploy. I would appreciate it if you would contact me and let me know whether or not any such regulations or guidelines exist. Thank you for your cooperation, courtesy and attention to this request. |
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ID: nht95-4.76OpenTYPE: INTERPRETATION-NHTSA DATE: November 14, 1995 FROM: Terence J. Kann TO: Ricardo Martinez -- Administrator, NHTSA TITLE: NONE ATTACHMT: 12/22/95 letter from Samuel J. Dubbin to Terence J. Kann (A43; Std. 108) TEXT: I am writing to you concerning Standard No. 108, which amended 49 CFR Part 571 to require application of retro-reflective sheeting or reflex reflectors to provide for greater conspicuity of the sides and rear of trailers. I have the following question. Section S3, Application (a) provides that the standard applies to ". . . trailers (except pole trailers) . . .". Section S5.7 provides that "each trailer of 80 or more inches overall width and with GVWR over 10,000 pounds manufactured on or after 12/1/ 93, except a trailer designed exclusively for living or office use, shall be equipped with either retro-reflective sheeting . . . reflex reflectors . . . or a combination . . .". My question is, are pole trailers such as those used in the logging industry, required to have retro-reflective sheeting, reflex reflectors, or a combination? If not, did the NHTSA issue any explanation for failing to extend the requirements to pole t railers? If yes, could you please provide a copy? Thank you for your assistance. Please don't hesitate to call or write if you have any questions or comments regarding the above. |
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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.