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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 12091 - 12100 of 16490
Interpretations Date

ID: nht72-6.34

Open

DATE: 06/29/72

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Truck Body and Equipment Association Inc.

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of May 30, 1972, forwarding to us correspondence you received from Mr. Calvin D. Kunkle of FMC Corporation. Mr. Kunkle's question, as explained in a telephone conversation we had with him on (Illegible Words), is whether building vehicles whose actual loaded weight exceeds the gross vehicle weight rating of the chassis violates Federal Law. Mr. Knuckle stated that he believed certain manufacturers of fire-fighting vehicles were presently doing that.

If the loaded weight is clearly inconsistent with the definitions of GVWR and GAWR as specified in 49 CFR S71.3, the manufacturer will be in violation of the Certification regulations, 49 CFR Part 567) and may be subject to civil penalties. Also, if the loaded weight of the completed vehicle or the weight imposed on any of its axle systems exceeds the stated ratings, the vehicle might be found by NHTSA to contain a safety-related defect. In such a case, the manufacturer is required to mail notification of the defect to all the purchasers. In addressing whether such a safety defect exists, the NHTSA considers the situation as a whole, including such factors as the manufacturer's ratings, and the true capacity of the vehicles.

We advised Mr. Kunkle during our conversation that if he will furnish to NHTSA the names of companies he suspects are involved in this practice, we will take action to bring them into conformity with the requirements.

ID: 11435ZTV

Open

Herr Tilman Spingler
Robert Bosch GmbH

FAX 49-7121-35-1792

Dear Herr Spingler:

We have received your FAX of December 18, 1995, asking whether it is permissible under Motor Vehicle Safety Standard No. 108 "to achieve both high- and lowbeam of a headlamp with only one single light source?" If the answer is yes, you would like to know which photometric requirements are applicable, saying that, in any event, it will meet the photometric requirements of any beam in which it is operated.

Use of a single light source (which we interpret to mean a single replaceable light source with a single filament) to provide both beams is not prohibited. While not specifically identified, it is permissible in either integral beam headlighting systems specified in paragraph S7.4 of Standard No. 108 or replaceable bulb headlighting systems of S7.5. Each such headlamp in a two-headlamp system is required by S7.4(a)(2) to be designed to conform to the photometrics of Figure 17A or Figure 27 for integral beam systems, or either Figure 17A or Figure 27 for replaceable bulb systems, depending on the type of light source used.

If this is a new type of replaceable light source, the relevant information required by Part 564 for such light sources would need to be submitted in advance of its use, in accordance with that regulation.

If you have any questions, you may refer them to Taylor Vinson of this Office.

Sincerely,

Samuel J. Dubbin Chief Counsel ref:108 d:1/29/96

1996

ID: nht70-2.45

Open

DATE: 12/30/70

FROM: AUTHOR UNAVAILABLE; R. H. Compton; NHTSA

TO: The Grote Manufacturing Company

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of December 5, 1970, to Mr. Julian E. Ieysath of this office concerning mounting of clearance lamps and testing combination lamps.

The wording for the mounting requirements of clearance lamps was amended in Standard No. 103 (35 F.R. 16040) to provide clarification; there was no intent to change the actual requirements. S4.3.1.7 permits clearance lamps in Standard No. 103 (35 F.R. 16840) to provide clarification; there was no intent to change the actual requirements. S4.3.1.7 permits clearance lamps to be mounted on the cab of a truck tractor, which in many cases may not indicate the overall width of the vehicle.

Section L of SAE J575, as modified by S4.2.1 of the amended standard, states, "The device shall be operating in the test in the same manner as it will be operated in service." Combination lamps have therefore been tested for less warpage with the steady burning tail or parking lamp operating continously and with the turn signal flashing. Now that the lens warpage test will also apply to the stop and backup lamps, this Bureau will test a combination lamp under the most severe possible operating condition. Since it is possible to have the tail, stop and backup lamps on simultaneously, these functions will be operating during the test for the stop and backup lamp lenses. A second test with the tail, turn signal and backup lamps operating will also be conducted.

Petitions for reconsideration have been received in Docket 69-18 requesting that the 10 minute cycling test be changed to 5 minutes on and 5 minutes off or that the effective date for the stop and backup lamp lens warpage requirement be extended beyond the July 1, 1971, effective date. Our decisions on these petitions will be published in the Federal Register in the near future.

ID: nht90-4.52

Open

TYPE: Interpretation-NHTSA

DATE: November 1, 1990

FROM: Mitch L. Williams -- President, Hella Inc.

TO: Richard Van Iderstine -- Office of Vehicle Safety Standards

TITLE: Re Proposed new product from Hella

ATTACHMT: Attached to letter dated 11-8-90 from Mitch L. Williams to Richard Van Iderstine; Also attached to letter dated 12-24-90 from Paul Jackson Rice to Mitch L. Williams (A37; FMVSS 108)

TEXT:

Hella is considering introducing a new product which could have certain safety implications. We are considering introducing a range of rear spoilers with integrated third rear brake lights. Obviously, for vehicles which are not equipped originally with third rear brake lights, this would upgrade them to current safety standards.

Our question is from a regulatory viewpoint, how would NHTSA view the addition of a rear spoiler with integrated third rear brake light to a vehicle already originally equipped with a third rear brake light? Could you be so kind as to give us an opinion on this matter?

Thank you for your assistance in this matter.

ID: nht91-7.55

Open

DATE: December 30, 1991

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: Wallace F. Forbes -- Planar Support Systems, Inc.

TITLE: None

ATTACHMT: Attached to letter dated 11-11-91 from Wallace F. Forbes to Office of the Chief Counsel, NHTSA

TEXT:

This responds to your November 11, 1991 letter in which you asked whether there are any standards that apply to a product you are developing. The product is a "portable back support product which people would be likely to use in their automobiles as well as in other environments."

By way of background information, the National Highway Traffic Safety Administration (NHTSA) does not provide approvals of motor vehicles or motor vehicle equipment. Under the National Traffic and Motor Vehicle Safety Act (Safety Act), it is the responsibility of the manufacturer to ensure that its motor vehicles and equipment meet applicable requirements. The following provides our opinion based on the facts provided in your letter.

Your product would fall within NHTSA's jurisdiction if it is an item of "motor vehicle equipment" as that term is defined in S102(4) of the Safety Act. Section 102(4) defines "motor vehicle equipment" as:

any system, part, or component of a motor vehicle as originally manufactured or any similar part or component manufactured or sold for replacement or improvement of such system, part, or component or as any ACCESSORY, OR ADDITION TO THE MOTOR VEHICLE ... (emphasis added).

In determining whether an item is an "accessory ... to the motor vehicle," NHTSA applies two criteria. The first criterion is whether a substantial portion of the expected uses of the item are related to the operation or maintenance of motor vehicles. The agency determines the expected uses by considering product advertising, product labeling, and the type of store that retails the product, as well as available information about the actual use of the product. The second criterion is whether the product is intended to be used principally by ordinary users of motor vehicles (E.G., items normally used by professional vehicle repair and maintenance personnel would not qualify). If the product satisfies both criteria, the product is considered to be an "accessory" and this is subject to the provisions of the Safety Act.

While your letter does not provide sufficient information for us to determine whether your product would satisfy the first criterion, you should be able to make a determination based on the factors set forth above. If your product did satisfy the first criterion, it would appear to satisfy the second criterion.

If your product is an item of motor vehicle equipment, NHTSA has not issued any safety standards that would directly apply to your product. However, there are two statutory provisions of which you should be aware. First, S108(a)(2)(A) of the Safety Act states that:

No manufacturer, distributor, dealer, or motor vehicle repair business shall knowingly render inoperative, in whole or in part, any device or element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with an applicable Federal motor vehicle safety standard...

These commercial entities could sell your product, but could not install it if the installation would negatively affect the vehicle's compliance with the safety standards. The standards your product would be most likely to affect are those for occupant protection in interior impacts (Standard No. 201), head restraints (Standard No. 202), and flammability resistance (Standard No. 302). (The safety standards are found in Title 49 of the Code of Federal Regulations, Part 571.) Please note however, that the render inoperative prohibition would NOT apply to vehicle owners who install your product in their own vehicles.

Second, if your product is an item of motor vehicle equipment, Planar Support Systems would be a motor vehicle equipment manufacturer. As a manufacturer, you would be subject to the requirements of S151-159 of the Safety Act, concerning the recall and remedy of products with defects related to motor vehicle safety. If you or the agency determined that your product had a defect related to motor vehicle safety, you would have to notify all product purchasers of the defect, and either repair or replace the product. An information sheet for new manufacturers is enclosed.

I hope this information is helpful. If you have any more questions about this issue, feel free to contact Mary Versailles at this address or by telephone at (202) 366-2992.

ID: nht75-5.50

Open

DATE: 10/01/75

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Maslansky; Niles; Dougherty & Boyajian

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your letter of August 31, 1975, in which you ask whether National Highway Traffic Safety Administration (NHTSA) approval is necessary before selling imported inertia switches in this country.

No specific NHTSA approval is required. However, you should be aware of the regulations governing the importation for sale of motor vehicle equipment into the United States. These regulations provide in part that if imported motor vehicle equipment is not certified by the manufacturer as having complied with all applicable Federal Motor Vehicle Safety Standards, upon entry the importer must file a declaration that no safety standards were applicable to the equipment at the time it was manufactured, that the equipment is exempt from applicable safety standards, or that the equipment has been or shortly will be brought into compliance with applicable safety standards (19 CFR @ 12.80(b)).

The NHTSA has issued no safety standards concerning inertia switches in motor vehicle electrical systems. However, the agency recently issued on Advanced Notice of Proposed Rulemaking (40 FR 40853, September 4, 1975) on the subject of motor vehicle electrical system integrity, with the intent of eventually issuing a safety standard in that area.

We hope this information is of assistance. If you have any further questions, please write us.

ID: nht76-5.65

Open

DATE: 09/03/76

FROM: AUTHOR UNAVAILABLE; Frank A. Berndt; NHTSA

TO: Pillsbury; Madison & Sutro

TITLE: FMVSR INTERPRETATION

TEXT: This responds to your May 11, 1976, question whether @ 574.7 of Part 574 (Tire Identification and Record Keeping) (49 CFR Part 574), requires that the brand name owner of a single tire brand must supply to its dealers tire registration forms that conform to the dimensions specified for the "universal form" described in Figure 3 of the regulation. You also request confirmation that a tire registration form "which fits credit card imprinters and provides for the registration of only two tires" is similar in format to the form described in Figure 3.

Section 574.7 of the regulation specifies in part that ". . . forms conforming in size and similar in format to Figure 3 shall be provided to those dealers who request them. . . ." As stated in the preamble accompanying the requirement, the purpose of the specification is to ease the problem of the multi-brand dealer who was "faced with a multiplicity of different forms and procedures for tire registration" (39 FR 19482, June 3, 1974). The requirement that the "universal form" conform in size as well as format was added in conjunction with a similar requirement for dealers, in response to petitions for reconsideration of the June amendment (39 FR 28658, November 1, 1974).

Review of the changes indicates clearly that the requirement for conformity in size of the "universal form" was directed only to the situation of multi-brand dealers. The NHTSA does not consider the manufacturer or brand name owner of one tire brand to be subject to this requirement in the case of a dealer who sells only one brand of tires. It is clear that any advantage in the storage of different forms from different tire manufacturers would not apply in the case of a one-brand dealer. Accordingly, the NHTSA interprets @ 574.7 to not require conformity in the size of forms supplied by a tire manufacturer, brand name owner, or its designee, in the case of requests from dealers that sell only one brand of tire.

In answer to your second request, the NHTSA considers a tire registration form which provides for the registration of only two tires to be similar in format to the form described in Figure 3. Any variation from the size of the form described in Figure 3 would, of course, be subject to the limitation just discussed.

SINCERELY,

PILLSBURY, MADISON & SUTRO

May 11, 1976

Standard Oil Company of California - Atlas Tire Registration Forms

Fred Schwartz, Esq. Office of Counsel National Highway Traffic Safety Administration Department of Transportation

Please refer to our recent telephone conversation concerning the requirements imposed by 49 CFR Section 574.7 (as amended November 1, 1974). The section reads, in relevant part, as follows:

". . . forms conforming in size and similar in format to Figure 3 shall be provided to those dealers who request them, or if the dealer prefers, he may supply his own form as long as it contains the required information, conforms in size, and is similar in format to Figure 3."

The foregoing requirement is imposed upon the "tire manufacturer, brand name owner and retreader or his designee." Apparently Standard Oil Company of California as the designee of the owner of the "Atlas" brand name would be subject to the requirement.

The previous version of this provision merely required that forms "similar to Figure 3" be provided. I understand that the objective of the change was in large part to simplify storage and choice of forms for dealers and in part to simplify data processing for a particular company which processes tire registration forms for many small tire manufacturers. As Standard does its own data processing and does not retain the registration cards, I question whether the Company must provide forms of the standard dimensions to dealers who may request them merely for their own convenience in storage. It appears to me that unless all forms are meant to be and are actually interchangeable at the dealer's end, no purpose is served by imposing this requirement on Standard. It is estimated that it will cost the Company $ 30,000 annually to comply with the new size requirement as the form is part of a warranty and information booklet slightly different in size. I would appreciate your comments.

Second, would you kindly confirm your telephone advice that the location of the required information on the form is not prescribed by the format of Figure 3; specifically, a redesigned form which fits credit card imprinters and provides for only two tires per registration form would still be "similar in format to Figure 3" within the meaning of the regulation.

Judith E. Ciani for Pillsbury, Madison & Sutro

ID: nht72-6.36

Open

DATE: 02/03/72

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Truck Trailer Manufacturers Association

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of December 20, 1971, asking whether the Certification regulations (Docket Nos. 70-6, 70-8, 70-15) apply to pole trailers. The Docket numbers you refer to also include the regulations concerning "Vehicles Manufactured in Two or More Stages."

As there are no motor vehicle safety standards presently applicable to pole trailers, neither the Certification regulations (49 CFR Part 567) nor the regulations governing "Vehicles Manufactured in Two or More Stages" (49 CFR Part 568) apply to them. As you were informally informed, however, pole trailers manufactured on or after January 1, 1973, that are equipped with air brake systems would be required to comply with Motor Vehicle Safety Standard No. 121, and their manufacturers would be required to comply with the Certification regulations and, where applicable, the regulations governing Vehicles Manufactured in Two or More Stages.

ID: nht76-3.5

Open

DATE: 04/13/76

FROM: STEPHEN P. WOOD FOR FRANK A. BERNDT -- NHTSA

COPYEE: BUREAU OF MOTOR CARRIER SAFETY

TITLE: FMVSS INTERPRETATION

TEXT: I am writing in response to your March 22, 1976, telephone conversation with Mark Schwimmer of this office concerning the treatment of plastic fuel tanks under Federal Motor Vehicle Safety Standard No. 301-75, Fuel System Integrity.

As Mr. Schwimmer explained, the National Highway Traffic Safety Administration has issued no safety standards that apply directly to fuel tanks. Standard No. 301-75, which applies to entire vehicles, specifies fuel spillage requirements for barrier crash and rollover tests, but does not include a flame envelopment test. In addition to passenger cars and school buses, the vehicles that are subject to the standard are multipurpose passenger vehicles, trucks, and buses with a Gross Vehicle Weight Rating of 10,000 pounds or less.

Standard No. 301-75 applies to new vehicles. In addition, the Federal Highway Administration's Bureau of Motor Carrier Safety has established requirements for certain vehicles in use in interstate commerce. I understand that a fuel tank flame envelopment test is among these. For information concerning such a test, you should communicate with that agency.

For your convenience, a copy of Standard No. 301-75 is enclosed.

ID: nht68-3.5

Open

DATE: 12/31/68

FROM: AUTHOR UNAVAILABLE; R. M. O'Mahoney; NHTSA

TO: Brixtax (London) Ltd.

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of December 9, 1968, in which you inquire about the certification responsibilities of equipment manufacturers under the National Traffic and Motor Vehicle Safety Act of 1966.

You state that it is your understanding that a vehicle manufacturer has the responsibility to certify the entire vehicle, including equipment that is produced by other manufacturers and covered by Federal safety standards, as complying with the applicable standards, and that the basis on which that manufacturer satisfies himself that equipment from suppliers conforms to the standards is a matter of his own discretion. I consider that statement to be essentially correct, with the caveat that the manufacturer must be able to show, under @ 108(b)(2) of the Act, that "he did not have reason to know in the exercise of due care" that any included equipment was nonconforming. What constitutes "due care" must be determined in light of all the circumstances of a particular case. You are also correct in your understanding that approval by the States has no relevance to the question of compliance with this Federal law.

Finally, regardless of certification requirements all equipment must conform to applicable standards, and certification by the equipment manufacturer is required if the equipment is ultimately sold in the aftermarket.

I am pleased to be of assistance.

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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