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: nht90-2.37OpenTYPE: INTERPRETATION-NHTSA DATE: 05/01/90 FROM: BRAD MAGOR TO: DEPARTMENT OF TRANSPORTATION OFFICE OF VEHICLE SAFETY COMPLIANCE ENFORCEMENT TITLE: NONE ATTACHMT: ATTACHED TO LETTER DATED 06/28/90 FROM PAUL JACKSON RICE -- NHTSA TO BRAD G. MAGOR; A35; PART 591 TEXT: We are moving back to the States (S.C.) from Canada in the near future. Ideally, we would like to buy a truck or van up here to help us with our move, though we don't want to get stuck with a vehicle that we can't use or eventually sell in the States. C ould you give us any information on what features cars or trucks require to meet U.S. safety standards. Do you know if Canada or Canadian cars generally have these items. Thank you very much for this information and your assistance. |
|
ID: nht72-1.23OpenDATE: 06/28/72 FROM: AUTHOR UNAVAILABLE; L. R. Schneider; NHTSA TO: Rubber Manufacturers Association TITLE: FMVSS INTERPRETATION TEXT: This is in reply to your letter of June 9, 1972, asking whether the National Traffic and Motor Vehicle Safety Act prompts the various States from enforcing the Vehicle Equipment Safety Commission's Regulation V-1 with respect to passenger car tires. Section 103(d) of the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1392(d) requires any State law applicable to the same aspect of motor vehicle performance as a Federal motor vehicle safety standard to be identical to the Federal standard. We believe this section, considered in light of Federal Motor Vehicle Safety Standard No. 109, invalidates any State law that requires passenger car tires (except tires procured by a State for its own use) to meet the VESC Regulation V.1, or to be labeled with the V-1 symbol. |
|
ID: 22204.ztvOpenM. Guy Dorleans Dear M. Dorleans: This is in reply to your letter of September 20, 2000, asking for interpretations of 49 CFR Part 564 and Federal Motor Vehicle Safety Standard No. 108. Your company is presently developing "a headlamp which incorporates a replaceable gas-discharge light source with a ballast as a dedicated power supply." The light source is one for which information has been filed pursuant to 49 CFR Part 564 in Docket No. National Highway Traffic Safety Administration (NHTSA) 98-3397. The ballast, which is "completely encased in the headlamp, is not removable from the headlamp, and is not sold as a spare part," is not part of the list. You believe that the requirements of Part 564 do not apply to this headlamp and that you are not required to submit the information specified in Sec. 564.5(d)(1), (2), and (3). Under the provisions of Sec. 564.5(d), a manufacturer may request modification of a light source for which information has previously been submitted. Because the ballast is a listed part necessary for interchangeability (Sec. 564, Appendix B, paragraph V, subsection A), you must submit the ballast part number. Even though the ballast is incorporated in the headlamp, and its part number is the same as the headlamp, its part number must be submitted because it is a modification of the basic information regarding light sources whose information is already listed in the Part 564 docket. You have a question relating to Standard No. 108 as well. Paragraph S7.7(e)(1) through (e)(7) specifies marking requirements for ballasts necessary for operation of replaceable light sources. One face of the ballast in Valeo's headlamp is visible from outside the headlamp. You have asked whether the ballast in the Valeo headlamp must be marked in accordance with S7.7(e). Paragraph S7.7(e) is the only NHTSA regulation that imposes specific requirements on ballasts. The paragraph does not distinguish between ballasts that are integrated into a headlamp and those that are exterior to it. The intent of the marking requirement is to inform the reader primarily of product identification, rated laboratory life of the light source/ballast combination, warning of potential shock hazard, and a DOT certification to these requirements. In our opinion, these markings are required under the headlamp design you posit, one in which a ballast is incorporated into the headlamp housing and is not replaceable alone. If you have further questions, you may refer them to Taylor Vinson of this Office (202-366-5263). Sincerely, Frank Seales, Jr. ref:108 |
2000 |
ID: nht78-1.11OpenDATE: 12/05/78 FROM: AUTHOR UNAVAILABLE; J. Levin, Jr.; NHTSA TO: Volvo of America Corporation TITLE: FMVSS INTERPRETATION TEXT: This is in response to your letter of September 20, 1978, requesting an interpretation of Federal Motor Vehicle Safety Standard No. 101-80, Controls and Displays. Specifically, you asked whether the km/h label on Volvo speedometers could appear in upper case letters instead of the lower case letters appearing in Table 2 of the standard. The answer is yes. Section 5.2.3 of the standard provides that "any such display for which no symbol is provided in Table 2 shall be identified by the word or abbreviation shown in column 3." There is no requirement that the identifying words or abbreviations be in the same type face, type size, or case as those printed in the Federal Register. Therefore, as long as the abbreviations are the same as those appearing in Table 2 and are visible, no problem arises because Volvo wishes to use upper case, rather than lower case letters. SINCERELY September 20, 1978 Joseph J. Levin, Jr. Chief Counsel Department of Transportation National Highway Traffic Safety Administration Subject: Request for Interpretation, FMVSS No. 101-80 Dear Mr. Levin: According to Federal Motor Vehicle Safety Standard No. 101-80, the speedometers of 1981 and later model year passenger vehicles are to be labelled "MPH" and "km/h". It is our understanding that it is the intent of this requirement, along with FMVSS No. 127, to encourage the use of metric units of speed and distance. It is also the intent of this standard to present information to the vehicle operator as clearly and unambiguously as possible. Enclosed is a preliminary example of a Volvo proposed speedometer face. Picture A is the proposed 1981 model year speedometer. Note that in this case, the metric unit for speed is labelled "KM/H". In other words, we have used upper case letters, but in exactly the same configuration. We believe that using the upper case letters does not detract from the clarity of the information being conveyed, nor does it discourage use of the metric system. Thus, we interpret the use of "KM/H" to satisfy the requirement of FMVSS No. 101-80. Please advise us as to whether you agree with our interpretation of this standard. If I can be of any assistance, please feel free to call. VOLVO OF AMERICA CORPORATION Product Planning and Development William Shapiro, P.E. Manager, Regulatory Affairs |
|
ID: nht90-2.34OpenTYPE: INTERPRETATION-NHTSA DATE: 04/26/90 FROM: KENNETH E. TOMPOR -- AUTO BROKERS AND LEASING LTD TO: STEPHEN P. WOOD -- NHTSA TITLE: IMPORT OF 1985 FERRARI 288 GTO AS OF TODAY, APRIL 26, 1990 ATTACHMT: ATTACHED TO LETTER DATED 04/30/90 FROM STEPHEN P. WOOD -- NHTSA TO KENNETH E. TOMPOR; REDBOOK A35; PART 593; LETTER DATED 06/19/89 FROM KEN TOMPOR -- AUTO BROKERS AND LEASING TO JOSEPH THRASHER -- NEWPORT BEACH POLICE DEPARTMENT TEXT: IN 1988, I PURCHASED FROM A MR. RAYMOND DEANGELO IN LOS ANGELES CALIFORNIA THE ABOVE MENTIONED FERRARI, SERIAL #54245. THE CAR WAS PAID FOR ON OCTOBER 10, 1988 AND WHILE TRANSPORTATION WAS BEING ARRANGED TO MYSELF IN MICHIGAN, MR. DEANGELO REMOVED THE V EHICLE FROM MY LOS ANGELES STORAGE AREA "AS HE CHANGED HIS MIND". THE VEHICLE AND MONIES HAVE NOT BEEN RETURNED, AND AS YOU MAY HAVE GUESSED A LAWSUIT WAS INITIATED. MY COURT CASE AGAINST MR DEANGELO WILL BEGIN TUESDAY, MAY FIRST, IN FEDERAL COURT, AND I NEED AT THAT DATE A LETTER STATING THAT THAT VEHICLE TODAY CANNOT BE BROUGHT INTO THE UNITED STATES LEGALLY. WE ARE SUEING TO GET THE VEHICLE, NOT MONETARY DAMAGES, AND NEED TO SPECIFY THE UNIQUENESS OF IT IN THAT IT CANNOT BE REPLACED LEGALLY TODAY. MR. TAYLOR VINSON HAS GIVEN ME YOUR NAME AND ASSURED ME THAT YOU WOULD BE SO KIND AS TO FURNISH ME WITH A LETTER TO SUBSTAINIATE THIS STATEMENT. I WOULD APPRECIATE FAX-BACK ON MONDAY 4-30, AS CASE BEGINS ON MAY 1, 1990 THANKING YOU IN ADVANCE, I REMAINI N 1988, I PURCHASED FROM A MR. RAYMOND DEANGELO IN LOS ANGELES CALIFORNIA THE ABOVE MENTIONED FERRARI, SERIAL #54245. THE CAR WAS PAID FOR ON OCTOBER 10, 1988 AND WHILE TRANSPORTATION WAS BEING ARRANGED TO MYSELF IN MICHIGAN, MR. DEANGELO REMOVED THE VE HICLE FROM MY LOS ANGELES STORAGE AREA "AS HE CHANGED HIS MIND". THE VEHICLE AND MONIES HAVE NOT BEEN RETURNED, AND AS YOU MAY HAVE GUESSED A LAWSUIT WAS INITIATED. MY COURT CASE AGAINST MR DEANGELO WILL BEGIN TUESDAY, MAY FIRST, IN FEDERAL COURT, AND I NEED AT THAT DATE A LETTER STATING THAT THAT VEHICLE TODAY CANNOT BE BROUGHT INTO THE UNITED STATES LEGALLY. WE ARE SUEING TO GET THE VEHICLE, NOT MONETARY DAMAGES, AND NEED TO SPECIFY THE UNIQUENESS OF IT IN THAT IT CANNOT BE REPLACED LEGALLY TODAY. MR. TAYLOR VINSON HAS GIVEN ME YOUR NAME AND ASSURED ME THAT YOU WOULD BE SO KIND AS TO FURNISH ME WITH A LETTER TO SUBSTAINIATE THIS STATEMENT. I WOULD APPRECIATE FAX-BACK ON MONDAY 4-30, AS CASE BEGINS ON MAY 1, 1990 THANKING YOU IN ADVANCE, I REMAIN |
|
ID: nht75-3.39OpenDATE: 09/10/75 FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA TO: Duo-matic Importers LTD. TITLE: FMVSS INTERPRETATION TEXT: This responds to Duo-matic's August 19, 1975, question whether Standard No. 121, Air Brake Systems, applies to an air brake coupler device that connects air brake hoses from a truck to the trailer it tows. The answer to your question is no. Paragraph S3 (Applicability) of Standard No. 121 states that the standard applies to trucks, buses, and trailers equipped with air brake systems (with some stated exceptions). The standard therefore applies only to vehicles, and does not apply to motor vehicle equipment such as the Duo-matic coupler device. SINCERELY, August 19, 1975 Richard B. Dyson Assistant Chief Council Office of the Chief Council Federal Highway Administration Refer to: A: Your letter N-40-30(MIS) dated 6-3-75 B: Motor Vehicle Safety Standard #121 as amended S5.3.3 Brake Actuation Time. With attached amendments of 11-12-74, 1-7-75, 1-17-75, 3-4-75, 3-21-75, 3-26-75, 5-15-75, and 6-11-75. C: Duo-Matic Double Quick Release Coupling for Semi-Trailers (452-803) D: Duo-Matic Double Quick Release Coupling for Towing Trailers (452 802) The question is if Reference B above applies to our Wabco Westinghouse Duo-Matic coupler, which replaces the Glad Hand coupling now in use. Your interpretation would be very much appreciated. We have enclosed two copies each of references C & D. H. Melvin Strand, President |
|
ID: nht75-6.20OpenDATE: 03/21/75 FROM: BYRON CRAMPTON -- TRUCK BODY AND EQUIPMENT ASSOCIATION MANAGER OF ENGINEERING SERVICES TO: CHIEF COUNSEL NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION TITLE: NONE ATTACHMT: ATTACHED TO LETTER DATED 08/19/75 EST, FROM RICHARD B. DYSON TO BYRON CRAMPTON; N40-30; OPINION FILE, STANDARD 108 TEXT: Dear Sir: Recently several members of the Truck Body and Equipment Association have raised questions concerning state versus federal motor vehicle lighting requirements. The vehicle in question is a multipurpose passenger vehicle less than eighty (80) inches wide, equipped with a raised roof. Our question is as follows: Can a state require a motor vehicle to be equiped with lights not required under FMVSS #108? Thanking you in advance for your help, I am, Very truly yours, |
|
ID: 86-5.48OpenTYPE: INTERPRETATION-NHTSA DATE: 11/17/86 FROM: JOHN GRIFFIN -- PRESIDENT FRAZER BILT INC TO: TAYLOR VINSON -- LEGAL COUNSEL N.H.T.S.A. U.S. DEPT. OF TRANSPORTATION TITLE: NONE ATTACHMT: ATTACHED TO LETTER DATED 03/06/87 FROM ERIKA Z. JONES -- NHTSA TO JOHN GRIFFIN, REDBOOK A30, STANDARD 108, ID AND CLEARANCE LAMP TEXT: Dear Sir: Mr. Kevin Cavey suggested that I write you regarding issues of interest to our company. We manufacture emergency medical service vehicles (ambulances). These vehicles are typically mounted on a light duty truck chasis, and are over 80" in width. The ambulance industry typically defers to the opinions and rulings of the Federal Motor Vehicle Safety Standards in the placing of identification and clearance lights on emergency vehicles. This often presents a conflict with respect to placing emergency lights and/or lightbars at preferred locations on the ambulance. For example, a light bar above the double rear doors may be placed as high as possible and thereby give no room for identification lights. A similar situation with a front light bar is not relevant since the chassis manufacturer places clearance and identification lamps on the driver's cab roof. Mr. Cavey indicated his belief that fire engines and E.M.S. vehicles may be exempt from identification and clearance light requirements, but I have not found such a statement in the preamble to Standard 108. Please advise me of any ruling that might clarify this issue. Thank you for your cooperation. Sincerely |
|
ID: nht95-3.85OpenTYPE: INTERPRETATION-NHTSA DATE: August 10, 1995 FROM: Charles De Saint Martin -- Project Manager, Fairchild Corporation TO: John Womack -- General Counsel, U.S. DOT TITLE: NONE ATTACHMT: ATTACHED TO 9/14/95 LETTER FROM JOHN WOMACK TO CHARLES DE SAINT MARTIN (A43; REDBOOK 2; STD. 108) TEXT: Dear Mr. Womack: A telephone conversation with Mrs. Patricia Breslin of D.O.T. prompts to write. She informed me that your office was responsible for providing new product interpretation. We, at Fairchild are currently looking at establishing a partnership with a French company, regarding the marketing of the following product: Product description: The product, named "SECURIFLASH", adds security to vehicles by alerting other vehicles of emergency braking situations. Goal: Differentiate emergency braking from conventional braking by automatically triggering off the warning signals in addition to the standard brake lights. An electronic device, attached to the engine's block, releases the warning signals at time of extreme deceleration, as if the driver had done it by hand. The product does not in any way affect or alter the original equipment of the car. It should be considered as an additional warning signals switch which automatically triggers off in case of emergency braking. This product was developed after different European studies show that 60% of rear end collisions would be avoided if the brakes had been applied one second earlier. Waiting for your correspondence. Attachment (Brochure Omitted.) |
|
ID: nht95-6.8OpenTYPE: INTERPRETATION-NHTSA DATE: August 10, 1995 FROM: Charles De Saint Martin -- Project Manager, Fairchild Corporation TO: John Womack -- General Counsel, U.S. DOT TITLE: NONE ATTACHMT: ATTACHED TO 9/14/95 LETTER FROM JOHN WOMACK TO CHARLES DE SAINT MARTIN (A43; REDBOOK 2; STD. 108) TEXT: Dear Mr. Womack: A telephone conversation with Mrs. Patricia Breslin of D.O.T. prompts to write. She informed me that your office was responsible for providing new product interpretation. We, at Fairchild are currently looking at establishing a partnership with a French company, regarding the marketing of the following product: Product description: The product, named "SECURIFLASH", adds security to vehicles by alerting other vehicles of emergency braking situations. Goal: Differentiate emergency braking from conventional braking by automatically triggering off the warning signals in addition to the standard brake lights. An electronic device, attached to the engine's block, releases the warning signals at time of extreme deceleration, as if the driver had done it by hand. The product does not in any way affect or alter the original equipment of the car. It should be considered as an additional warning signals switch which automatically triggers off in case of emergency braking. This product was developed after different European studies show that 60% of rear end collisions would be avoided if the brakes had been applied one second earlier. Waiting for your correspondence. Attachment (Brochure Omitted.) |
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.