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: nht89-3.2OpenTYPE: INTERPRETATION-NHTSA DATE: 09/22/89 FROM: JOHN D. DINGELL -- CHAIRMAN COMMITTEE ON ENERGY AND COMMERCE TO: JEFFREY R. MILLER -- ACTING ADMINISTRATOR NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION DEPARTMENT OF TRANSPORTATION TITLE: NONE ATTACHMT: ATTACHED TO LETTER DATED 11/29/89 ESTIMATED, FROM JEFFREY R. MILLER -- NHTSA TO JOHN D. DINGELL -- HOUSE; REDBOOK A34; STANDARD 205; LETTER DATED 08/25/89 FROM CONSTANCE A. MORELLA -- HOUSE TO NORMAN Y. MINETA -- HOUSE; LETTER DATED 07/31/89 FR OM W. MARSHALL RICKERT -- MVA TO CONSTANCE A. MORELLA; LETTER DATED 07/08/88 FROM ERIKA Z. JONES -- NHTSA TO NORMAN D. SHUNWAY -- CONGRESS; STANDARD 205; LETTER DATED 11/01/88 FROM ERIKA Z. JONES -- NHTSA TO BEVERLY B. BYRON -- HOUSE; STANDARD 205 TEXT: Dear Mr. Miller: Enclosed is a letter from Congresswoman Morella inquiring about the requirements of Federal law and regulations regarding the tinting of windows for valid medical reasons. I request your comments, including whether regulatory relief is possible and w ise. Please provide a copy of your reply to the Congresswoman. With best wishes. Sincerely, ENCLOSURE |
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ID: nht89-1.65OpenTYPE: INTERPRETATION-NHTSA DATE: 04/04/89 FROM: NANCY L. BRUCE -- OFFICE OF CONGRESSIONAL AFFAIRS DEPARTMENT OF TRANSPORTATION TO: CHESTER ATKINS -- MEMBER, U.S. HOUSE OF REPRESENTATIVES 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 03/29/89 FROM CHESTER G. ATKINS -- HOUSE TO NANCY BRUCE -- DOT, RE MRS. BLANCHE KOZAK; LETTER DATED 09/26/88 FR OM BLANCHE KOZAK TO BERRY FELRICE; LETTER DATED 10/16/79 FROM EDWIN P. RIEDEL; REPORT UNDATED; LETTER DATED 08/09/88 FROM BLANCHE G. KOZAK TO DEPARTMENT OF TRANSPORTATION TEXT: Dear Mr. Atkins: Thank you for your letter forwarding correspondence from your constituent, Mrs. Blanche Kozak. I have transmitted your inquiry to the appropriate Departmental officials who are familiar with this matter and they will respond to you directly. I appreciate your contacting me and hope you will not hesitate to call if I can be of any further assistance. Sincerely, |
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ID: nht88-3.45OpenTYPE: INTERPRETATION-NHTSA DATE: 09/12/88 FROM: NANCY F. MILLER -- US DEPARTMENT OF TRANSPORTATION TO: BEVERLY B. BYRON -- U. S. HOUSE OF REPRESENTATIVES TITLE: NONE ATTACHMT: ATTACHED TO LETTER DATED 10/27/88 FROM ERIKA Z JONES TO BEVERLY B BYRON; REDBOOK A 32, STANDARD 205; LETTER DATED 08/25/88 FROM BEVERLY B BYRON T. NANCY MILLER; MEMORANDUM DATED 08/14/83 FROM C. RICHARD FRAVEL TO WHOM IT MAY CONCERN RE JOSEPH C IAMPA JR; MEMORANDUM DATED 08/04/88 FROM ARTHUR J. LOMART TO WHOM IT MAY CONCERN; LETTER DATED 08/01/88 FROM C.E. SHUE TO JOSEPH CIAMPA RE 0590630; LETTER DATED 08/24/88 FROM JOSEPH L. CIAMPA TO BEVERLY B. BYRON TEXT: Dear Ms. Byron: Thank you for your letter forwarding correspondence from your constitutent, Mr. Joseph L. Ciampa, Jr. I have transmitted your inquiry to the appropriate Departmental officials who are familiar with this matter and they will respond to you directly. I appreciate your contacting me and hope you will not hesitate to call if I can be of any further assistance. |
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ID: nht89-3.18OpenTYPE: INTERPRETATION-NHTSA DATE: 10/17/89 FROM: NANCY L. BRUCE -- DIRECTOR OFFICE OF CONGRESSIONAL AFFAIRS DOT TO: THE HONORABLE GEORGE MILLER -- MEMBER, U.S. HOUSE OF REPRESENTATIVES TITLE: NONE ATTACHMT: ATTACHED TO LETTER DATED 12/1/89 FROM STEPHEN P. WOOD -- NHTSA TO U.S. CONGRESSMAN GEORGE MILLER; REDBOOK A34; STANDARD 125; LETTER DATED 10/12/89 FROM GEORGE MILLER, U.S. CONGRESSMAN TO NANCY BRUCE -- D.O.T. OFFICE OF CONGRESSIONAL AFFAIRS; LE TTER DATED 10/4/89 FROM DELL RANDLE TO CONGRESSMAN GEORGE MILLER; LETTER DATED 9/8/89 FROM ELIZABETH M. LUCAS -- NATIONAL SAFETY COUNCIL, PRODUCT DEVELOPMENT TO DELL RANDLE OF SHIKARI CONSULTANT FIRM LTD. TEXT: Dear Mr. Miller: Thank you for your letter forwarding correspondence from your constituent, Mr. Dell Randle. I have transmitted your inquiry to the appropriate Departmental officials who are familiar with this matter and they will respond to you directly. I appreciate your contacting me and hope you will not hesitate to call if I can be of any further assistance. Sincerely, |
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ID: nht69-1.22OpenDATE: 09/12/69 FROM: CHARLES A. BAKER -- NHTSA OFFICE OF STANDARDS ON ACCIDENT AVOIDANCE MOTOR VEHICLE SAFETY PERFORMANCE SERVICE TO: WARREN M. HEATH -- COMMANDER, ENGINEERING SECTION DEPARTMENT OF CALIFORNIA HIGHWAY PATROL TITLE: NONE ATTACHMT: LETTER DATED 08/29/69; FROM WARREN M. HEATH TO ROBERT BRENNER -- NHTSA TEXT: Dear Mr. Heath: Thank you for your letter of August 29, 1969, to Dr. Robert Brenner, Acting Director, National Highway Safety Bureau, concerning the flashing of sidemarker lamps when the turn signal switch is activated. Paragraph S3.5 of Federal Motor Vehicle Safety Standard No. 108 permits the flashing of sidemarker lamps simultaneously with the turn signal lamps on the side to which a turn is contemplated. Sincerely, |
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ID: nht91-7.33OpenDATE: December 5,1991 FROM: Harvey D. Benson -- Chief Engineer, Landoll Corporation TO: Richard Carter -- Office of Vehicle Safety Standards, NHTSA TITLE: None ATTACHMT: Attached to letter dated 2/3/92 from Paul Jackson Rice to Harvey D. Benson (A39; Std. 121) TEXT: I need answers for two questions: 1. Is a HEAVY HAULER TRAILER required to have spring brades? We manufacture tandem and triple axle trailers with capacities up to 12O,OOO GVWR which have load carrying decks less than 40 inches above the ground. Our understanding of 49 CFR Ch V, 571.121 is that spring brakes are not required but there may be other regulations which apply. I have had customers call stating that they were ticketed for not having spring brakes. I need a definitive statement referencing specific regulations to answer this question. 2. What are the requirements for bulkhead (cab protection) on truck chassis beds? We manufacture slide back beds mounted on single and tandem axle truck chassis. I have not been able to find requirements as to size and impact capacity for cab protecting bulkheads. |
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ID: nht91-5.50OpenDATE: September 16, 1991 FROM: William Engel -- Assistant Chief, Covington (Kentucky) Fire Department TO: Paul Jackson Rice -- Chief Counsel, NHTSA TITLE: None ATTACHMT: Attached to letter dated 11-7-91 from Paul Jackson Rice to William Engel (A38; Std. 206); Also attached to letter dated 8-13-80 from Frank Berndt to L. Steenbock; Also attached to letter dated 2-11-88 from Erika Z. Jones to Joanne Salvio (Std. 206) TEXT: I am writing to you with a question about your Federal Motor Vehicle Safety Standard #206. My question is "are door locks required on fire equipment"? Our specifications required them on our new equipment, but the manufacturer stated that they are not required. Could you give me the official answer on this question? |
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ID: nht95-3.57OpenTYPE: INTERPRETATION-NHTSA DATE: JULY 25, 1995 FROM: Robert J. Ponticelli -- President, American International TO: John Womack -- Acting Chief Counsel, NHTSA TITLE: NONE ATTACHMT: ATTACHED TO 9/19/95 LETTER FROM JOHN WOMACK TO ROBERT J. PONTICELLI (A43; REDBOOK 2; STD. 114) TEXT: Dear Mr. Womack, I would like to request an opinion on the regulations concerning an aftermarket anti-theft device. This device is installed between the steering wheel and the steering shaft. When a key swich is activated the steering wheel is disengaged and becomes freewheeling, preventing the vehicle from being driven. I am requesting an interpretation of federal regulations to identify any restrictions or conditions which apply to this device when installed on a motor vehicle. Please distinguish which, if any, would apply to a regulated party such as a new car dea ler and to aftermarket service businesses. Thank you for your time and assistance with this matter, any information you could provide would be greatly appreciated. If you have any questions concerning this device I can be reached at (800) 336-6500 ext. 528 |
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ID: nht88-3.28OpenTYPE: INTERPRETATION-NHTSA DATE: 08/30/88 FROM: ERNIE J. BUNNELL -- PACIFIC T-TOPS INC. TO: TAYLOR VINSON -- LEGAL COUNCIL US DEPT. OF TRANSPORTATION TITLE: NONE ATTACHMT: ATTACHED TO LETTER DATED 11/03/88 FROM ERIKA Z JONES TO ERNIE J. BUNNELL; REDBOOK A32, STANDARD 108 TEXT: Dear Taylor, I was refered to you by the Department of Transportation regarding FMVSS #108 and the following: The Department of Transportation guidelines for aftermarket and OEM rear spoilers which when mounted on the deck lid of a car obstruct the high mounted stoplamp. Enclosed you will see (2) versions of rear spoilers (A) and (B): A) It is designed to be at or below the rear brake light using the 5 degrees measurement as a guide. B) It is designed to go over the horizontal intensity of the light. We have been advised that the attachment does not need to comply with the ruling. However, we would like to know what the requirements are so that we can comply if possible. If you need any additional information regarding this, please contact me. I shall look forward to hearing from you. |
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ID: nht91-2.10OpenDATE: March 6, 1991 FROM: Earl C. Lempke -- President, Delavan Industries Inc. TO: Taylor Vinson -- NHTSA (Dot) TITLE: None ATTACHMT: Attached to letter dated 3-27-91 from Paul Jackson Rice to Earl C. Lempke (A37; VSA 1392(d); Std. 108) TEXT: You have been referred to us by Truck Lite Corporation as their contact with the Government concerning Trailer Lighting. Delavan is the major Manufacturer of Automobile Transport Trailers and have been building this equipment for forty-five years. Our question, is there any federal ruling stating that Trailer Clearance Lights are considered as Safety Equipment and as such are not to be included as part of the overall width of the vehicle? Believe it or not, Truck Lite has nothing they can refer to us to substantiate this. Is there any ruling on this matter which you could send us? Thank you for your help and please call me (800-258-2528) if you need any more information. Attachment Copy of Federal Highway Administration Federal Motor Safety Regulations dated January, 1990, regarding S393.19 - S393.22, page 184. (Text 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.