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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



Displaying 4021 - 4030 of 6047
Interpretations Date

ID: nht67-1.21

Open

DATE: 05/15/67

FROM: AUTHOR UNAVAILABLE; George C. Nield; NHTSA

TO: Fire Apparatus Manufacturers Association, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: Your March 7, 1967, letter to Dr. William Haddon, Jr., requested that you be advised regarding the applicability of lighting requirements, as spacified in the Initial Motor Vehicle Safety Standards to fire apparatus.

With exception as noted in Section 255.7, page 2409 of the Federal Register, Volume 32, Number 23, dated February 3, 1967 (copy enclosed), the lighting requirements will be applicable to fire apparatus. Initial Standard No. 108 covers lighting requirements for vehicles (as specified therein) that are 80 or more inches wide overall and becomes effective January 1, 1968. A Notice of Proposed Rule Making (see page 2418) of enclosed Federal Register includes a Proposed Amendment to Standard No. 108 and a Proposed Initial Standard No. 112, covering vehicles (as specified therein) that are less than 80 inches wide overall. It is anticipated that the proposed Amendment and Initial Standard No. 112 will also become effective on January 1, 1968.

Thank you for your interest in the Motor Vehicle Safety Standards.

FIRE APPARATUS MANUFACTURERS ASSOCIATION, INC.

March 7, 1967

Dr. WILLIAM HADDON, JR. -- NHTSA

We have an inquiry from one of our members as to whether or not all of the lighting standards under the Initial Federal Motor Vehicle Safety Standards as published in the Federal Register Volume 32, Number 23, Part II dated Friday, February 3, 1967 will apply to fire apparatus.

Will you please advise us on this matter so that we may inform our members.

Thank you for your prompt attention.

C. L. Koepenick Secretary-Treasurer

ID: nht67-1.23

Open

DATE: 08/10/67

FROM: AUTHOR UNAVAILABLE; George C. Nield; NHTSA

TO: Thermo King Corporation

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your letter of July 11, 1967, regarding the applicability of the Federal Motor Vehicle Safety Standards to accessories which are purchased for installation after procurement of the car and, in particular, Safety Standard No. 201.

Standard No. 201, "Occupant Protection in Interior Impact -- Passenger Cars," applies only to vehicles as originally equipped and does not apply to accessories such as "after market" auto air conditioners. However, the public would certainly benefit from the maximum degree of conformance that may be feasible on after market installations.

It is sincerely regretted that a written response to your first request was not received by you and trust that you were not inconvenienced.

March 14, 1967

Dr. William Haddon Department of Commerce

As manufacturers of "after market" auto air conditioners, the National Traffic and Motor Vehicle Safety Act as passed on January 23, 1967, is of concern to us. Does this Safety Act apply to manufacturers of accessories which are purchased by the car owner after he receives the car? The case in point is a car owner which purchases an "add-on" auto air conditioner; must this accessory comply with Standard 201?

Recently one of our Engineers (Mr. D. Gregerson) contacted your office (Clayboure) and received verbal "no" answers to the above questions. Your aides mentioned that this could be confirmed by requesting it by letter. We would appreciate this confirmation when convenient for you.

Very truly yours,

L. L. Willis Vice President - Engineering

ID: nht69-2.16

Open

DATE: 09/30/69

FROM: AUTHOR UNAVAILABLE; Robert Brenner; NHTSA

TO: Honorable John A. Blatnik

COPYEE: FHWA LEGAL 26-30; CONG. LIA.; MR. HITCKCOCK; OFF ACCIDENT AVOIDANCE, MVSPS

TITLE: FMVSS INTERPRETATION

TEXT: This is in further reply to your letter of September 9, 1969, in reference to the motor vehicle safety items discussed in Mr. Frank L. Van Alstine's letter of July 2, 1969, to Mr. H. M. Jacklin, Jr., Acting Director of our Motor Vehicle Safety Performance Service. I am enclosing a copy of our reply to Mr. Van Alstine's letter.

As we indicated in our reply, Federal Motor Vehicle Safety Standard No. 107, "Reflecting Surfaces - Passenger Cars, Multipurpose Passenger Vehicles, Trucks and Buses," affects only original installation; it does not apply to replacement windshield wiper arms, such as those referred to in Mr. Van Alstine's letter.

Federal Standard No. 210 specifies strength and general location requirements for lap and shoulder belt anchorages in passenger cars. Even though vehicles such as Mr. Van Alstine's 1969 Plymouth Valiant must meet this standard, some degree of discomfort may be experienced with certain(Illegible Word) positions and/or certain occupant sizes. As our reply stated, we are not aware of any significant injuries resulting from the present belt anchorage locations.

Based on the information supplied by Mr. Van Alstine, it does not appear that the two situations described represent violations of Federal Motor Vehicle Safety Standards.

It is most helpful to our efforts to improve highway safety when concerned citizens such as Mr. Van Alstine take the time to bring their safety experiences to our attention and that of their elected representatives.

Enclosure

ID: nht69-2.17

Open

DATE: 10/16/69

FROM: AUTHOR UNAVAILABLE; H. M. Jacklin, Jr.; NHTSA

TO: E.T.R.T.O.

TITLE: FMVSS INTERPRETATION

TEXT: This will acknowledge your recent submittal of data to the National Highway Safety Bureau, concerning the addition of the belted-bias tire construction as a new category within Table I of Appendix A of Federal Motor Vehicle Safety Standard No. 109. Your submittal was not accompanies by a cover letter.

The National Highway Safety Bureau realizes that this construction of motor vehicle passenger car tires warrants consideration within Standard No. 109. We do not believe, however, that the introduction of additional tables to the standard is needed to cover belted-bias tires. The tables within the standard are becoming voluminous and the variety of size designations are confusing to the consumer.

During the recent ISO/TC 31 meetings in Rome, Mr. W. W. Jordan, Chief of the Tire Branch discussed briefly with members of your organization our philosophy on the standardization of the tire size designations and load inflation schedules. We have been working closely with the American Tire and Rim Association in further developing the alphanumerical system for tire size designations. We believe we are approaching a workable, standardized solution to the problem. In this light, we understand that members of E.T.R.T.O. visit the United States at regular intervals and we would like to extend an invitation to your organization to have a representative meet with us to review this matter and your petition in detail.

The National Highway Safety Bureau, at the present time, does not plan to differentiate belted-bias type tire construction from other constructions, consequently, we will delay action on your petition until we have the opportunity to discuss it with your representative.

ID: nht70-1.10

Open

DATE: 05/22/70

FROM: AUTHOR UNAVAILABLE; Rodolfo A. Diaz; NHTSA

TO: Micro Machinery Products

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your comments and suggestions contained in your April 23, 1970, letter to Mr. Douglas Toms concerning motor vehicle Safety.

In your letter, you ask that the Bureau clarify whether a dealer who sells "Micro-siped" tires that do not comply with Standard No. 109 would be subject to a civil penalty. Section 108(a) of the National Trafic and Motor Vehicle Safety Act of 1966 (15 U.S.C.et seq.) prohibits any person from manufacturing for sale, selling or offering for sale any item of motor vehicle equipment unless it is in conformity with Federal Motor Vehicle Safety Standards. The prohibitions specified in the Act, do not apply after the first purchase in good faith for purposes other than resale (108(b)(1)). Therefore, if a dealer offers for sale or sells new tires that have been micro-siped and those tires do not comply with Standard No. 109 he would be subject to a civil penalty of up to $ 1,000 for each tire that did not comply. This penalty provision would not be applicable, however, if the tires to be micro-siped are owned by the user of the tires.

It is noted for your information that section 569.7(c) of the Regrooved Tire Regulation (formerly 369.7(c), copy enclosed) prohibits the sale, offer for sale, or introduction in interstate commerce "siped tires produced by cutting the tread surface of a regrooved or regroovable tire without removing rubber, if the tire cord material is damaged as a result of the siping process, or if the tire is siped deeper than the original, retread, or regrooved groove depth."

Your interest in the motor vehicle safety program is greatly appreciated.

ID: nht70-1.26

Open

DATE: 10/20/70

FROM: R. A. Diaz; NHTSA

TO: L. C. Lundstrom; GM

TITLE: FMVSS Interpretation

TEXT: The Director has asked me to reply to your letter of September 29, 1970, concerning the compliance of certain motor vehicles, which General Motors intends to import, with Federal Motor Vehicle Safety Standard No. 206 - Door Locks and Door Retention Components.

Each rear door of these vehicles has, in addition to a "conventional" locking mechanism, a special locking mechanism which is described in your letter as:

"an additional lever located on the rear edge of each door which, when placed in its 'lock position', will only allow the door to be opened from outside the vehicle even if the conventional locking knob on the upper portion of the door inside the vehicle is in the unlocked position. The additional lever is covered when the door is closed."

You ask whether the rear doors on these vehicles comply with @4.1.3 of Standard No. 206, which requires that each door "shall be equipped with a locking mechanism with an operating means in the interior of the vehicle."

A somewhat similar problem was discussed in the preamble to the April 27, 1968 amendment (33 F.R. 6465) to the Standard. As stated there, @4.1.3 does not preclude the installation of a special locking mechanism in addition to the required locking mechanism. However, the required locking mechanism must be able to be engaged or disengaged regardless of whether any additional locking mechanism is engaged or disengaged. If the special locking mechanism does not interfere with the operation of the required locking mechanism on the doors in question, therefore, it will not constitute a failure to comply with the standard.

Please write if I can be of any further assistance.

ID: nht70-1.31

Open

DATE: 01/09/70

FROM: AUTHOR UNAVAILABLE; C. A. Baker; NHTSA

TO: Dr. N. Kinon

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your letter of November 14, 1969, concerning electrically heated windshields.

At present, we do not have a Federal Motor Vehicle Safety Standard which deals specifically with electrically heated windshields. This does not mean, however, that various states may not have restrictions covering this matter. Standard No. 205 stipulation both visibility and structural performance requirements for glazing surfaces used in automobiles as well as in other vehicles. If the product you manufacture meets the requirements of Standard No. 205, then it is acceptable under our existing regulations.

We assume from previous conversations with Mercedes Benz that this electrically heated windshield would be offered as an optional piece of equipment. We understood that it would be used as a supplement to the standard blower-type defrosting system. If this is actually the case, then the electrically heated windshield would not have to meet the performance requirements of Standard No. 108, but the blower-type unit would have to pass the defrosting test.

We recognize that the automotive industry has shown an increasing interest in using electrically heated glass to defrost windows. At present, several manufacturers offer electrically heated glass in the rear window (backlight) as an optional piece of equipment. Assuming that this product helps defrost glazing surfaces, we recognize that it has a safety potential that should be effectively utilized.

On the other hand, we also recognize that this product could interfere with visibility, depending upon the wire size pattern and location. This is an area which needs further study.

ID: nht70-1.50

Open

DATE: 04/01/70

FROM: AUTHOR UNAVAILABLE; R. A. Diaz; NHTSA

TO: Florence L. Dawson

TITLE: FMVSS INTERPRETATION

TEXT: Your letter of March 2, 1970, to Mr. Douglas Toms concerning the failure of the electrical system in your 1968 Volkswagen has been forwarded to this office for reply.

Present Federal Motor Vehicle Safety Standards include no specific requirement for electrical systems. However, there are minimum performance requirements for certain vehicle components--such as a brake system warning light and various lighting components--which necessarily rely upon a properly functioning electrical system for compliance with the applicable Standards.

I have enclosed for your information a booklet describing briefly the Federal Standards which are presently in force. A copy of the complete Standards publication and all supplements may be purchased at an annual price of $ 8.00 from the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20102.

This Bureau does not become involved in individual contractual relationships, such as exists between you and(Illegible Word) Motors or Volkwagon of America, Incorporated. Accordingly, we cannot assist you in obtaining further repairs for your vehicle. We are, however, interested in your experience from the point of view that what you have encountered might occur in other 1965 Volkwagon vehicles. Presently, we have no knowledge of other related failure, but we have made note of your complaint and we will remain alert for any similar reports.

The National Traffic and Motor Vehicle Safety Act of 1966 does not create a right of action by which a vehicle owner way sue a vehicle manufacturer if a safety-related defect is discovered in a vehicle. I suggest you contact an attorney as to possible recourse under Pennsylvania law.

Thank you for providing us with the opportunity to review your experience.

ID: nht70-1.7

Open

DATE: 03/28/70

FROM: AUTHOR UNAVAILABLE; R. A. Diaz; NHTSA

TO: Industrija Gouijevih

TITLE: FMVSS INTERPRETATION

TEXT: In response to your letter of January 8, 1970, the Department of Transportation hereby assign number 212 to Sava, Industrija Gouijevih,(Illegible Words) Jugoslavija as its approved code mark. The approved code mark is for use in identifying the tire manufacturer in accordance with S4.3 of Federal Motor Vehicle Safety Standard No. 107, and the National Traffic and Motor Vehicle Safety Act of 1966 (15 USC 1421(1)).

You are correct that all passenger car tires manufactured after August 1, 1968 must have permanently molded into or onto them the approved "DOT" recital. However, the application of the recital is not to import purposes only. The application of the(Illegible Words) by a tire manufacturer is the tire manufacturers self certification that his tire conforms to all of the minimum performance requirements of Federal Motor Vehicle Safety Standard No. 109. Standard 109 specifies tire dimensions and laboratory test requirements for bend unseating resistance, strength, endurance and high speed performance; defines tire load ratings; and specifies labeling requirements. A copy of the standard is enclosed.

The National Highway Safety Bureau does not certify tires prior to the manufacturer's application of the "DOT" symbol. However, we do maintain a compliance test program by which certification of manufacturers are verified. Violations of this certification are subject to a fine of $ 1,000.00 per tire.

Your attention is directed to the requirements for designation of an agent in accordance with the National Traffic and Motor Vehicle Safety Act of 1966, Subsection (110(a)). This requirement is implemented by our General Procedural Rules, Subpart D - Service of Process: Agents. I have enclosed a copy of those requirements for your information.

ID: nht70-2.14

Open

DATE: 06/22/70

FROM: AUTHOR UNAVAILABLE; R.A. Diaz; NHTSA

TO: General Motors Technical Center

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of May 7, 1970, requesting approval of an equivalent test procedure for interior compartment doors, in place of those specified in S3.3.1(a) and (c) of Standard No. 201.

Since the phrase "approved equivalent test procedure" appeared in the initial Federal motor vehicle safety standards, the Bureau's position on this subject has undergone some clarification. The manufacturer's primary responsibility is to produce vehicles or equipment that, when tested according to the applicable standards, meet the stated requirements. Although a manufacturer is responsible for ensuring that his products meet all the requirements of the standards, there is nothing in the Act that requires a manufacturer to perform any predetermined series of tests. If a particular test is actually "equivalent" to the procedure described in the standard, in the sense that the test results can be accurately correlated to the standard's requirements, there is no need to request approval of the Bureau, and there would be no legal significance to the approval if given. Conversely, if the test is not equivalent, so that an item that "possed" the test might still fail to conform to the standard, the request would be actually for a lowering of the standard, which could not be done without rulemaking procedures. For this reason, we will not grant the approval in the form in which it was requested.

The procedure that you described does, however, appear to be a distinct improvement in the method of testing this aspect of performance. We intend to initiate rulemaking procedures directed at amending the standard to incorporate that test.

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.

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