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: nht88-2.90OpenTYPE: INTERPRETATION-NHTSA DATE: 08/08/88 FROM: JACK SATKOSKI -- SPECTRA ENTERPRISES TO: OFFICE OF CHIEF COUNCIL NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION TITLE: NONE ATTACHMT: 6/19/89 letter from Stephen P. Wood to Jack Satkoski (Std. 201; Std. 302; VSA 108(A)(2)(a)) TEXT: I have enclosed five sketches and a photograph of a sun visor extender being developed for market at Spectra Enterprises. The product is called the ADD-VISOR and consists of a magnetic base and moveable panel that attaches by means of velcro straps to t he existing auto, truck, or RV's sun visor. The moveable panel is designed so that it can be positioned in areas to block the sun not covered by existing sun visors. The size of the product is 11.5 in by 4.5 in., has rounded corners, and is made from soft and flexible vinyl related magnetic materials. Can you please advise and send me copies if applicable, any federal standards this product will have to meet prior to marketing. I also require suggestions on similar contacts to make at the state level for possible standards that may apply. Thanks for your time and consideration. Sincerely enclosures |
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ID: nht88-2.91OpenTYPE: INTERPRETATION-NHTSA DATE: 08/08/88 FROM: ALAN S. ELDAHR -- OPTIMUM BUILDING TECHNOLOGIES PRESIDENT TO: ERICA JONES -- CHIEF COUNCIL NATIONAL HIGHWAY TRAFFIC SAFETY COMMISSION TITLE: NONE ATTACHMT: ATTACHED TO LETTER DATED 08/17/89 FROM STEPHEN P. WOOD -- NHTSA TO ALAN S. ELDAHR; REDBOOK A34; VSA 108 [A] [2] [A]; STANDARD 108 TEXT: Dear Ms. Jones: Thank you for the information you sent us on Motor Vehicle Safety Standards. My company is interested in producing a small LED display reader board for use in private vehicles. The unit will measure approximately 1 1/2" x 12" and will display messages programmed by the driver. This can be accomplished in one of two ways. First, we can incorporate both the LED display and the high mounted stop lamp into one unit. The unit will be mounted on the vertical center line (as required for the stop lamp). Messages will display until the service brakes are applied, at which time the stop lamp will come on as usual. The second alternative is to produce the LED display as a separate unit, also to be placed in the rear window. This unit can either display messages continuously, or stop when service brakes are applied (as above). Both units will comply with all other safety standards: photometric requirements, visibility ranges and bulb replacement, and neither shall impair the effectiveness of any other lighting equipment required by the Motor Vehicle Safety Standards. We would appreciate a reply with your comments and input on any problems you might forsee with our format or design. Sincerely, |
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ID: nht88-2.92OpenTYPE: INTERPRETATION-NHTSA DATE: 08/09/88 FROM: BLANCHE G. KOZAK TO: CHIEF COUNCIL LEGAL DEPT. U.S. DEPT. OF TRANSPORTATION TITLE: NONE ATTACHMT: ATTACHED TO LETTER DATED 06/09/89 FROM STEPHEN P. WOOD -- NHTSA TO BLANCHE KOZAK; REDBOOK A33 [2]; VSA 108 [A] [1] [A]; LETTER DATED 04/04/89 FROM NANCY L. BRUCE -- DOT TO CHESTER ATKINS -- HOUSE; LETTER DATED 03/29/89 FROM CHESTER G. ATKINS -- HOUSE TO NANCY BRUCE -- DOT, RE MRS. BLANCHE KOZAK; LETTER DATED 09/26/88 FROM BLANCHE KOZAK TO BERRY FELRICE; LETTER DATED 10/16/79 FROM EDWIN P. RIEDEL; REPORT UNDATED TEXT: Dear Sir/Madam; Please be informed that I spoke to Ms. Williams, Supervisor NHTSA, on Aug. 9, 1988 and was advised to request a written statement from the Legal Dept. in regards to the Cushman Vehicle, Model #404. It is my understanding that the "on-road Cushman Veh icle is classified as a motorcycle under the current definitions found in the Code of Federal Regulations, Vol. 49, Part 571.3." by Barry Felrice of the Dept. of Transportation on July 22, 1988 to Rep. James J. Florio. My question is in regards to the Model # 404 which is the Off-road design manufactured by O.M.C. Lincoln Cushman-Ryan and sold by The Sawtelle Bros. for on road use in the Commonwealth of Massachusetts. When and by whom was this vehicle authoruzed fo r on road use as a motor vehicle and not a motorcycle. This information was requested of me by my State Senator for the purpose of having it in writing to present to the committee in the process of filing a bill on the State Level to have these Cushman Vehicles regulated in the Commonwealth of Massachuset ts. My Husband was killed on a Cushman Model # 404 while working for the Lawrence General Hospital on Dec. 9, 1980. This vehicle was sold to the LGH for on road use, for further information you may refer to my report of the accident to NHTSA on June 11, 1988. Thank you very much for your anticipated response to my plea. Gratefully yours |
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ID: nht88-2.93OpenTYPE: INTERPRETATION-NHTSA DATE: 08/10/88 EST FROM: ERIKA Z. JONES -- CHIEF COUNSEL, NHTSA TO: AMNON SHOMLO -- PRESIDENT, A.A.S. TITLE: NONE ATTACHMT: MEMO DATED 3-25-88, TO ERIKA JONES-NHTSA, FROM AMNON SHOMLO, OCC-1783 TEXT: This is in reply to your letter of March 25, 1988, enclosing a "Peace" decal designed to be affixed to the center highmounted stop lamp. The letters and design are in white, printed on transparent plastic, "in an effort to preserve the basic requirement s for an effective projected luminous area of the lens and the specified candela." You have asked what "Federal/Legal authorizations we need to obtain, stating that we comply with all the regulations and the requirements regarding this product." There are no regulations that apply directly to the decal, nor any Federal restrictions on its sale. Thus you cannot state in any sales materials that the product meets Federal requirements, for there are none. If a center highmounted brake lamp would continue to meet all applicable requirements of Motor Vehicle Safety Standard No. 108 after installation of your decal, there are no restrictions on its use. Although you intend the product to preserve the requirements of Federal Motor Vehicle Safety Standard No. 108, it is not certain that this will occur. The decal has the potential of obscuring light from some of the 13 test points at distances where cand ela photometrics must be measured and the specified minima met. However, its actual effect can be determined only through laboratory tests on lamps of different sizes and lens and reflector designs. Although you have no liability under Federal law for selling this decal, a violation of the National Traffic and Motor Vehicle Safety Act will result if the decal creates a noncompliance and if it is applied by a manufacturer, distributor, or dealer before the first sale of the vehicle. A violation will a lso occur if the decal creates a noncompliance and if it is applied after the vehicle's first sale by any of these persons or by a motor vehicle repair business. There is no violation of Federal law if the decal is applied by a person other than those named above, such as the vehicle owner. In the absence of a violation of Federal law there may nonetheless be State statutes restricting the application of the decal under any circumstances. We are unable to advise you on State laws. I hope that this answers your question. |
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ID: nht88-2.94OpenTYPE: INTERPRETATION-NHTSA DATE: 08/10/88 EST FROM: ERIKA Z. JONES -- CHIEF COUNSEL, NHTSA TO: M. ARISAKA -- MANAGER, AUTOMOTIVE LIGHTING, HOMOLOGATION SECT., STANLEY ELECTRIC CO., LTD. ATTACHMT: MEMO DATED 5-31-88, TO ERIKA Z. JONES, FROM M. ARISAKA-STANLEY ELECTRIC CO., LTD TEXT: This is in reply to your letter of May 31, 1988, asking about the acceptability of installing an additional red reflex reflector on the rear of a passenger car. The reflector would be centered between the two red reflex reflectors required by the standar d. In your opinion, the additional reflector will not impair the effectiveness of other lighting equipment required by Standard No. 108. As you have properly noted, supplementary motor vehicle equipment including reflectors is permissible under paragraph S4.1.3 of Standard No. 108 as long as it does not impair the effectiveness of equipment that the standard requires. The determination of whether supplementary equipment, in fact, impairs the effectiveness of the required equipment is initially that of the manufacturer of the vehicle upon which the supplementary equipment is to be installed, and who certifies compliance with all applicabl e Federal motor vehicle safety standards including paragraph S4.1.3 of Standard No. 108. The National Highway Traffic Safety Administration neither approves nor disapproves of specific vehicles designs, and unless there are reasons to believe that the s upplementary equipment will, in fact, impair the effectiveness of the required lighting equipment this agency accepts the manufacturer's determination. The drawing you attached shows the location of the two required rear reflex reflectors, and the supplementary one, but does not depict the location or types of other required rear lighting equipment, i.e. stop lamps, center highmounted stop lamp, taillam ps, turn signal lamps, license plate lamp, and backup lamps. However, in your opinion the reflector will not impair the effectiveness of these lamps and the required reflectors, and the agency has no reason to believe that the third reflector will, in fa ct, impair the effectiveness of them. I hope this answers your question, and that the guidelines given in this letter will encourage you to reach satisfactory determinations without the necessity of submitting them to this agency for comment. We appreciate your continuing interest in motor vehicle safety. |
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ID: nht88-2.95OpenTYPE: INTERPRETATION-NHTSA DATE: 08/10/88 FROM: ERIKA Z. JONES -- CHIEF COUNSEL NHTSA TO: PETER CAMERON-NOTT TITLE: NONE ATTACHMT: LETTER DATED 06/01/88 TO ERIKA Z. JONES FROM PETER CAMERON, OCC-2120; LETTER DATED 11/13/86 TO PETER CAMERON FROM FRANCIS ARMSTRONG, NEF 32GSH TEXT: Dear Mr. Cameron-Nott: This is in reply to your letter of June 1, 1988, with reference to importation of motor vehicle equipment included in an incomplete vehicle. You have stated that the kit will include brake hoses, brake fluid, and glazing, and that these items will conform with Motor Vehicle Safety Standards Nos. 106, 116, and 205 respectively, and that they will all carry the DOT symbol certifying compliance. You ask whether these items may be entered under Box 2 on the HS-7 importation form. The answer is yes. Box 2 (implementing 19 C.F.R. 12.80(b)(1)(ii)) allows importation without bond of motor vehicles and equipment manufactured to conform with, and certified as conforming to, all applicable Federal motor vehicle safety standards. Sincerely, |
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ID: nht88-2.96OpenTYPE: INTERPRETATION-NHTSA DATE: 08/10/88 FROM: ERIKA Z. JONES -- CHIEF COUNSEL NHTSA TO: STEPHEN BORKOWSKI TITLE: NONE ATTACHMT: LETTER DATED 06/24/88 TO ERIKA Z. JONES FROM STEPHEN BORKOWSKI, OCC - 2243 TEXT: Dear Mr. Borkowski: This is in reply to your letter of June 24, 1988, asking about the legality of your "Bimmer Dimmer Safety Stop Light Concept". The concept has as its goal to lessen the chance of rear end collisions, by governing "the intensity of brake light brightness to indicate the degree of braking being applied to a vehicle." Federal Motor Vehicle Safety Standard No. 108 Lamps, Reflective Devices, and Associated Equipment governs the legality of your concept. SAE Standard J586c Stop Lamps, August 1970, has been incorporated by reference, and specifies appropriate photometric requirements. Paragraph S4.5.4 of Standard No. 108 requires in pertinent part that "the stoplamps on each vehicle shall be activated upon application of the service brakes". We believe that this means that the lamp shall display the intensity that is designed into it to meet the photometrics of J586c. The photometrics are expressed in terms of a minimum for each test point and while there is not a corresponding maximum for each point, there is an overall maximum for the lamp. Thus, a lamp of variab le intensity could fall below the minimum at one or more test points or exceed the overall maximum. This, of course, would result in a noncompliance with Standard No. 108. The agency examined the problem of rear end collisions and concluded that the most appropriate way to address it was through the center highmounted stoplamp, required equipment on passenger cars manufactured on and after September 1, 1985. This is inten ded not only to reduce the incidence of rear end collisions but also their severity. We are interested in the possibility of further reductions in rear end collisions. Because your concept may be of interest to that Office, I am forwarding a copy of yo ur letter to the agency's Associate Administrator for Research and Development for such further correspondence as may be warranted. We appreciate your interest in motor vehicle safety. Sincerely, |
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ID: nht88-2.97OpenTYPE: INTERPRETATION-NHTSA DATE: 08/11/88 EST FROM: ERIKA Z. JONES -- CHIEF COUNSEL, NHTSA TO: SCOTT A. SNYDER TITLE: NONE ATTACHMT: MEMO DATED 3-10-88 TO NHTSA FROM SCOTT A. SNYDER TEXT: This is in reply to your letter of March 10, 1988, to the Department's regional office in Philadelphia, asking for a response concerning "ornamental lighting." In your opinion "a few extra lights on the side and rear of a vehicle would help other people see you better while driving at night." The agency is interested in the role that vehicle conspicuity plays in accidents and accident avoidance. With reference to motorcycles, we have amended our motor vehicle lighting standard to prescribe performance characteristics for headlamp modulation. We were prepared to amend the standard to require the activation of motorcycle headlamps when the ignition was turned on (but did not do so when we learned that almost all motorcycles were being wired to operate in that fashion). Some time ago we aske d the public to comment on ways of increasing the conspicuity of large vehicles as our research had indicated that reflective tape applied to the side and rear of wide trucks and trailers might lessen crashes and crash severity, and our research still co ntinues in this area. Most importantly we adopted the center highmounted stop lamp for passenger cars because of the ability it demonstrated in test fleets to reduce the frequency of rear end impacts. The type of lights of which you speak are referred to as "presence" lamps (as contrasted with "signal" lamps), and the agency over the years has acted with respect to all motor vehicles by requiring them to be equipped with side marker lamps, and by incr easing the lens area for stop lamps. As the Federal safety standards are by statutory definition "minimum" safety standards, the requirement that there be two taillamps, for example, does not mean that a manufacturer may not add two more if it wishes, o r any lighting device not covered by the standard. The sole restriction is that lighting devices added by the manufacturer or dealer that are in excess of the minimum must not impair the effectiveness of the equipment required by the standard. This cou ld happen, for example, if a fog lamp (not covered by the standard) was of an intensity and located so that it masked an adjacent front turn signal. With respect to nighttime operation, the critical issue would appear to be that additional lighting devi ces not create glare to oncoming and following drivers. The owner of the vehicle is not under a similar Federal restriction, and may personally add such additional lighting devices as seems desirable, subject to the laws of the States where the vehicle is registered and/or driven. However, the owner may not have these devices installed by a motor vehicle dealer or repair business if the result is to render wholly or partially inoperative any of the vehicle's original lamps or reflectors. We appreciate your suggestion for improving motor vehicle safety. |
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ID: nht88-2.98OpenTYPE: INTERPRETATION-NHTSA DATE: 08/11/88 FROM: ROBERT L. RIPLEY -- PRESIDENT KNAACK MANUFACTURING COMPANY TO: ERICA JONES -- OFFICE OF THE CHIEF COUNCIL NHTSA TITLE: NONE ATTACHMT: ATTACHED TO LETTER DATED 11/28/88 TO ROBERT L. RIPLEY FROM ERIKA Z. JONES, REDBOOK A32; STANDARD 556 TEXT: Dear Ms. Jones: I am enclosing copies of our three catalogs of products which we manufacture. I would appreciate it if you would review these catalogs and tell us whether we are required to file under Part 566, which requires motor vehicles and motor vehicle equipment manufacturers to supply NHTSA with information identifying themselves and describing products. I will await your reply. Thank you for your consideration. Sincerely, ENCLOSURE |
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ID: nht88-2.99OpenTYPE: INTERPRETATION-NHTSA DATE: 08/11/88 FROM: ERIKA Z. JONES -- CHIEF COUNSEL NHTSA TO: J. MIKE CALLAHAN -- PRECISION IMAGES TITLE: NONE ATTACHMT: LETTER DATED 04/14/87 TO TAYLOR VINSON FROM J MIKE CALLAHAN; OCC-409; LETTER DATED 11/19/87 TO ROGER M. COX FROM ERIKA Z JONES, STANDARD 108; LETTER DATED 09/03/87 TO DAVID M. ROMANSKY, FROM ERIKA Z JONES TEXT: Dear Mr. Callahan: This is in reply to your letter of April 14, 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. ENCLOSURE Sincerely, |
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.