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: nht94-1.16OpenTYPE: Interpretation-NHTSA DATE: January 10, 1994 FROM: Adam A. Freund -- Manager, Testing Services, Standards Testing Laboratories, Inc. TO: Walter Myers -- Office of Chief Counsel, NHTSA TITLE: Table II Minimum Static; Breaking Energy (inch pounds) D.O.T. 119 ATTACHMT: Attached to letter dated 4/12/94 from John Womack to Adam A. Freund (A42; Std. 119) TEXT: Further to our telephone conversation of this date, please find enclosed a copy of subject matter for your perusal. As we had discussed I believe there is a typo in the highlighted columns marked respectively MOTORCYCLE and ALL 12 INCH OR SMALLER RIM SI ZE. If I am correct the first column MOTORCYCLE should show a plunger diameter of 5/16" and the column marked ALL 12 INCH OR SMALLER RIM SIZE should show a plunger diameter of 3/4". I would appreciate your qualifying my interpretation of above subject matter. If my interpretation is incorrect, please advise me how the respective columns should be marked. Standards Testing Laboratories, Inc. would greatly appreciate any expedited consideration you may allow us on this request. ATTACHMENT (Table omitted.) |
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ID: nht94-9.7OpenTYPE: Interpretation-NHTSA DATE: January 10, 1994 FROM: Adam A. Freund -- Manager, Testing Services, Standards Testing Laboratories, Inc. TO: Walter Myers -- Office of Chief Counsel, NHTSA TITLE: Table II Minimum Static; Breaking Energy (inch pounds) D.O.T. 119 ATTACHMT: Attached to letter dated 4/12/94 from John Womack to Adam A. Freund (A42; Std. 119) TEXT: Further to our telephone conversation of this date, please find enclosed a copy of subject matter for your perusal. As we had discussed I believe there is a typo in the highlighted columns marked respectively MOTORCYCLE and ALL 12 INCH OR SMALLER RIM SIZE. If I am correct the first column MOTORCYCLE should show a plunger diameter of 5/16" and the column marked ALL 12 INCH OR SMALLER RIM SIZE should show a plunger diameter of 3/4". I would appreciate your qualifying my interpretation of above subject matter. If my interpretation is incorrect, please advise me how the respective columns should be marked. Standards Testing Laboratories, Inc. would greatly appreciate any expedited consideration you may allow us on this request.
ATTACHMENT (Table omitted.) |
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ID: nht93-7.7OpenDATE: October 1, 1993 Est. FROM: Bob Carver TITLE: None ATTACHMT: Attached to letter dated 11/22/93 from John Womack to Bob Carver (A41; Part 571; Std. 217) TEXT: I'm an engineer at Wayne Wheeled Vehicles, a commercial and school bus manufacturing company. My job here is to see ensure compliance to FMVSS 217, effective May 1994. I have a question for you in which I need an official ruling concerning FMVSS 217 S5.5.3(c): Each opening for a required emergency exit shall be outlined around its outside perimeter with a minimum 3 centimeters wide retroreflective tape, either red, white, or yellow in color, that when tested under the conditions specified in S6.1 of 571.131 meets the criteria specified in Table 1. If an emergency roof exit is required, is it necessary to outline it with the retroreflective tape even though it is not visible unless the bus is tilted on its side? Also, Charles Hott at NHTSA said that the width requirement will be revised to 1 inch. Can you confirm this? Thanks in advance for your prompt consideration and assistance concerning this matter. |
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ID: nht76-2.50OpenDATE: 02/09/76 FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA TO: Gillig Brothers School Bus Co. TITLE: FMVSS INTERPRETATION TEXT: This is in response to your request for information concerning methods of ensuring the compliance of school buses with the barrier crash test requirements of Federal Motor Vehicle Safety Standard No. 301-75, Fuel System Integrity. Standard No. 301-75, while establishing minimum performance levels, does not specify any particular design requirements for school bus fuel systems. A manufacturer is free to design his vehicles in the manner that he believes most appropriate to ensure compliance. To this end, you may find helpful information in a study by Dynamic Science entitled School Bus Safety Improvement Program. The NHTSA cannot assure you, however, that following the suggestions contained in the study will guarantee that your school buses will comply with the standard. The study is filed in the NHTSA's public docket as document number 75-03-GR1. Copies may be obtained by writing to: Technical Reference Branch National Highway Traffic Safety Administration Room 5108 400 Seventh Street, S.W. Washington, D.C. 20590 You should refer to the following publication numbers: HS 801-615, -616, and -617. |
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ID: nht71-4.40OpenDATE: 11/05/71 FROM: AUTHOR UNAVAILABLE; C. A. Baker for E. T. Driver; NHTSA TO: Truck-Lite Company TITLE: FMVSS INTERPRETATION TEXT: This is in reply to your letter of October 14, 1971, to Mr. Lewis Owen of this Office concerning an interpretation regarding your Truck-Lite No. 127 License plate light. The requested interpretation concerns the 8 degree incident light angle specified in SAE J587, "License Plate Lamps," as follows: "When a single lamp is used to illuminate the plate, the lamp and license plate holder shall bear such relation to each other that at no point on the plate will the incident light make an angle of less than 8 deg to the plane of the plate." Since the 8 degree incident light angle is also a requirement of Federal Motor Vehicle Safety Standard No. 108, all license plate lamp designs must conform to it. It is our position that the angle be measured from the optical center of the lens; therefore, the Electrical Testing Laboratories' position is valid. That is, the incident light angle of your lamp, without the paint shield and when mounted as it will be installed on the vehicle, is below the 8 degree minimum requirement. |
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ID: nht72-1.48OpenDATE: 03/10/72 FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA TO: Irvin Industries Inc. TITLE: FMVSS INTERPRETATION TEXT: This is in reply to your letter of February 23, 1972, in which you list information you wish to label on child seats you will manufacture, and ask whether the information as presented will comply with Motor Vehicle Safety Standard No. 213. You state that a label containing the model number, date of manufacture, and the company's name and place of business will be permanently affixed to the product, while a separate legend, containing other information, will be molded on the bottom of the seat in raised letters at least 3/32 inches high. The labeling scheme you wish to use would conform to paragraph S4.1 ("Labeling") of Standard No. 213, providing, of course, the blank spaces for model number and date of manufacture are appropriately filled in. We would suggest, however, that that part of the molded legend beginning" . . . and there is a minimum of 19 inches vertical clearance between this seating . . .", to the end of that provision be simplified to be more understandable to an ordinary consumer. WE ARE PLEASED TO BE OF ASSISTANCE. |
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ID: nht94-2.49OpenTYPE: INTERPRETATION-NHTSA DATE: April 19, 1994 FROM: S. Greiff -- PARS, Passive Ruckhaltesysteme GmbH TO: Chief Counsel -- US Department of Transportation, NHTSA TITLE: None ATTACHMT: Attached To Letter Dated 6/8/94 From John Womack To S. Greiff (A42; Std. 208) TEXT: Per Fax: 001/202-366-3820 Your "Laboratory Test Procedure For FMVSS 208/212/219/301" Gentleman: PARS is a company developing occupant restraint systems for the world wide automotive industry. One of our major topics is the development of airbag systems. For development and validation of the restraint systems we own a Barrier Impact Test Facility which was built up in 1993 new. Our runway is 80 m (260 feet's) long. The velocity tolerance up to 60 kph is +/- 0.1 kph. In your Laboratory Test Procedure for FMVSS testing, a minimum runway length of 500 feet is requested. We would like to ask you for an interpretation of your "500 feet requirement". It would be much appreciated, if we could get an answer by fax. Our fax no. is: 01149/6023/942-133 Thank you very much for your efforts in advance. Sincerely yours |
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ID: nht94-4.53OpenTYPE: INTERPRETATION-NHTSA DATE: October 14, 1994 FROM: Randal Busick -- President, Vehicle Science Corporation TO: Mary Versailles, Esq. -- Office of the Chief Counsel, NHTSA TITLE: Re: Request for interpretation of FMVSS 208 S7.1.2 ATTACHMT: Attached to 1/5/95 letter from Philip R. Recht to Randal Busick (A43; Std. 208; Std. 210) TEXT: Dear Ms Versailles: This is to request a clarification of FMVSS 208 S7.1.2. More specifically, would a seat belt system as shown on the attached drawing be in compliance with S7.1.2 as a so-called "semi-integrated" seat belt? As shown on the drawing, the inboard lower FMVSS 210 anchorage, n1 is located on the seat frame and thus, as the seat moves fore and aft, the system allows a minimum of two seat belt adjustment positions and the distance between the two extreme adjustmen t positions of the system is more than 5 cm. n1 The belt which holds the buckle is attached to this inboard anchorage. We look forward to your response. If you have any questions, kindly contact the undersigned. Sincerely Enclosure (Drawing omitted.) |
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ID: nht94-6.23OpenDATE: April 19, 1994 FROM: S. Greiff -- PARS, Passive Ruckhaltesysteme GmbH TO: Chief Counsel -- US Department of Transportation, NHTSA TITLE: None ATTACHMT: Attached To Letter Dated 6/8/94 From John Womack To S. Greiff (A42; Std. 208) TEXT: Per Fax: 001/202-366-3820 Your "Laboratory Test Procedure For FMVSS 208/212/219/301" Gentleman: PARS is a company developing occupant restraint systems for the world wide automotive industry. One of our major topics is the development of airbag systems. For development and validation of the restraint systems we own a Barrier Impact Test Facility which was built up in 1993 new. Our runway is 80 m (260 feet's) long. The velocity tolerance up to 60 kph is +/- 0.1 kph. In your Laboratory Test Procedure for FMVSS testing, a minimum runway length of 500 feet is requested. We would like to ask you for an interpretation of your "500 feet requirement". It would be much appreciated, if we could get an answer by fax. Our fax no. is: 01149/6023/942-133 Thank you very much for your efforts in advance. Sincerely yours |
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ID: nht68-4.1OpenDATE: 08/15/68 FROM: AUTHOR UNAVAILABLE; David A. Fay; NHTSA TO: Toyota Motor Company TITLE: FMVSS INTERPRETATION TEXT: Thank you for your letter of July 23, 1968, to Mr. George C. Nield, Acting Director, Motor Vehicle Safety Performance Service, concerning the requirements for turn signal and hazard warning signal flashers as specified by Motor Vehicle Safety Standard No. 108. With certain exceptions, paragraph S3.3 of Standard No. 108 permits the use of combination lamps, reflective devices and items of associated equipment, provided the requirements for each lamp, reflective device and item of associated equipment are met. Therefore, a combination turn signal and hazard warning signal flasher may be used, provided the requirements for each signal (turn and hazard warning) are met. You are correct in your understanding that Standard No. 108 and basically referenced SAE Standards J590 and J945 do not require operation of the flasher unit with only one signal bulb in the test circuit. The standard test circuit shown in Figure I of SAE Standard J823 indicates a minimum of two signal lamps and one pilot indicator lamp as the lamp load. Thank you for writing. |
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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.