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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 11991 - 12000 of 16510
Interpretations Date
 search results table

ID: nht72-6.14

Open

DATE: 11/10/72

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Truck Equipment & Body Manufacturers Association

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letters of September 25 and October 19, 1972. In your letter of September 25, you ask whether persons performing intermediate manufacturing operations are subject to the Defect Reports regulations, specifically that part of the regulations which requires the quarterly reporting of production figures (@ 573.5(b)). The defect reports regulations apply to all manufacturers of complete or incomplete motor vehicles. We consider intermediate manufacturers to be within the latter category, and the reguations therefore apply to them.

Your letter of October 19 asks whether a person who installs a fifth wheel in a pickup truck is considered a "remanufacturer." Under existing regulations, we would not consider the installation of a fifth wheel on a pickup truck to be a significant enough alteration to constitute remanufacturing. Under the recently proposed amendment to the Certification Regulations regarding the certification of altered vehicles (37 F.R. 22800, October 25, 1972), whether such a person would be an alterer and required to affix a new label to the vehicle would depend upon whether the fifth-wheel is a readily attachable component.

ID: nht72-6.15

Open

DATE: 08/16/72

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Thoroughbred Homes Inc.

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your inquiry of July 26, 1972, concerning the application of defect reporting requirements to mobile home manufacturers

Although mobile homes are not specifically mentioned in the National Traffic and Motor Vehicle Safety Act, they are considered to be motor vehicle subject to the Act. Because of their unique characteristics, mobile house have been categorized as a separate vehicle type, "mobile structure trailer," under the motor vehicle safety standards, 49 CFR Part 571. "Mobile structure trailer is defined in section 571.3 of that part.

The Defect Reports regulations (49 CFR Part 573) apply to manufacturers of all types of motor vehicles, including mobile structure trailers. They require manufacturers to report the number of vehicles manufactured during each calendar quarter. The description of the regulation's requirements in the article you enclosed is somewhat incomplete and accordingly we have enclosed a copy of the regulation for your guidance.

There are no specific forms which we require to be used in the submission of the specified informations. Copies of acceptable formats you may wish to use, however, are also enclosed.

ID: nht72-6.16

Open

DATE: 12/20/72

FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA

TO: Center for Auto Safety

TITLE: FMVSR INTERPRETATION

TEXT: Thank you for your letter of 20 November, 1972, concerning alleged non-compliance of the Defect Information Report regarding Volkswagen Windshield Wipers, submitted by Volkswagon of American on October 12, 1972, with the requirements of NHTSA's Defect Reports Regulations, 49 CFR Part 573. We agree that Volkswagen has failed to supply information required by sections 573.4(c)(2) and 573.4(c)(8) of the Regulation, specifically, the months of manufacture of the affected vehicles and a chronology which includes warranty claims, field service bulletins, and other such information. We are contacting Volkswagon to determine why the Company has failed to furnish that information and to attempt to obtain it. We also agree with your conclusion that 100% of 1948-1949 Volkswagens are potentially affected by the windshield wiper defect. However, Volkswagen's statement that 'no information is available" as to either the total number of such vehicles operating in the United States, or the percentage potentially affected satisfies the disclosure requirement of the regulation (49 CFR 573.4(c)(3, 4)).

We cannot agree, however, with your remaining assertions of non-compliance with the Regulations. While the Volkswagen Information Report is lacking in detail and is a poor example of an informational communication, it does contain minimal responses to the enumerated requirements of the Regulations.

Thank you for your interest in motor vehicle safety.

ID: nht72-6.17

Open

DATE: 03/17/72

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: CaraVan Custom Conversions

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of February 21, 1972, in which you request information on how to comply with the Defect Reports regulations (49 CFR Part 573). You state that your company converts vans into campers and other specialized uses, that some of your work is minor in nature, such as installing paneling, floors, or windows, and vents, and ask how to determine when you have developed a "model" for reporting purposes under the regulations.

The Defect Reports regulations apply to "manufacturers." As a general rule, a person who converts an already complete vehicle will be considered a manufacturer of the converted vehicle if he modifies it in such a way that the vehicle's structure or function is affected, to a significant extent. For example, a person who takes a basic van-type truck and makes extensive interior modifications to provide eating, sleeping, and bathroom facilities -- producing what might be called a motor home, although nomenclature is not determinative -- would be considered a manufacturer by the NHTSA. By contrast, a person who only added a window or some paneling at a customer's request would not be so considered. We recognize that a precise and universal line between these two polar examples is difficult to draw. For purposes of compliance with Part 573, we will accept a reasonable judgment on your part as to where the line should be drawn in your case.

Since your work is done a custom basis, you may consider the "make" and "model" language of the regulation as inapplicable to your production.

ID: nht72-6.18

Open

DATE: 08/31/72

FROM: AUTHOR UNAVAILABLE; Douglas W. Toms; NHTSA

TO: State Farm Mutual Automobile Insurance Company

TITLE: FMVSR INTERPRETATION

TEXT: This is in further response to your letters of May 3 and August 8, 1972, requesting that the NHTSA make available to insurance companies, such as State Farm, "vehicle identification numbers" (VIN's) which the companies could then utilize to independently notify policyholders whose vehicles have been subject to manufacturers' defect notification campaigns.

The NHTSA has reconsidered your request and has determined to propose, as an amendment to our Defect Reports regulations (49 CFR Part 573), that manufacturers be required to submit to the NHTSA the VIN's of vehicles subject to campaigns. The VIN's would be included in our public file and would be available to insurance companies and other groups who would wish to use them.

The NHTSA does not presently require manufacturers to submit the VIN's of campaigned vehicles (although the Defect Reports regulations do require manufacturers to compile the numbers for their own use). Because this will be a new requirement, the NHTSA is obligated by law to initiate rulemaking to provide for comments by interested persons, and to consider such comments in the decision as to whether the rule should be issued. We will take steps to publish the appropriate notice in the nearest possible future.

Your continuing interest in motor vehicle safety is, of course, greatly appreciated.

ID: nht72-6.19

Open

DATE: 09/06/72

FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA

TO: University of Puerto Rico

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your letter of July 20, 1972, requesting that we obtain for you vehicle identification numbers for vehicles involved in certain defect notification campaigns.

At present, manufacturers are not required to furnish vehicle identification numbers to the NHTSA. While they are required to compile them for their own purposes as part of their Owner Lists, as we indicated in our letter to you of July 5, 1972, we do not consider your request to be a justifiable reason for requesting this information from manufacturers. We appreciate your efforts with regard to the survey you have to conduct, but we do not believe it appropriate to require manufacturers to prepare and submit information to us purely on the basis of private individual requests.

Your letters, and others we have received, however, have demonstrated that a legitimate safety purpose can be served if identification numbers of vehicles involved in campaigns are made available to public and other groups. As a result, the NHTSA has determined to process to amend the Defect Reports regulations to require all manufacturers to supply vehicle identification numbers as part of the information they must submit pursuant to those regulations. Vehicle identification numbers would then be available to the public as a matter of course.

We have enclosed copies of quarterly reports which refer to three of the four campaigns you listed (General Motors, campaign number 71-G230: Toyota, campaign number (Illegible Word); and Volkswagen, campaign number 71-0005). Information on the fourth, Ford campaign number 71-0045, was not required to be submitted, and the manufacturer has not voluntarily submitted any to us.

ID: nht72-6.2

Open

DATE: 03/23/72

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: The Daystar Motor Homes Inc.

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of February 4 asking for copies of regulations applicable to a "motor home" you wish to manufacture.

I enclose a copy of the National Traffic and Motor Vehicle Safety Act of 1966, the basic statute setting forth your obligations as a manufacturer, and the authority for all applicable regulations. A publication titled "Federal Motor Vehicle Safety Standard and Other Regulations" is available from the Superintendent of Documents, Government Printing Office, Washington, D. C. 20402. The price of $ 8.00 includes a subscription of up to one year of supplements. The Federal standards and regulations also appear in Title 49 of the Code of Federal Regulations (Title 19 for the important regulations), generally available at law libraries. Amendments and proposals are published, when issued, in the Federal Register.

If you have any questions after obtaining and receiving these materials I will be happy to answer them for you. A "motor home" for your information, is defined as a "multipurpose passenger vehicle" under the Federal standards.

ID: nht72-6.20

Open

DATE: 07/05/72

FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA

TO: University of Puerto Rico

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of June 9, 1972, raising certain questions concerning the National Traffic and Motor Vehicle Safety Act, and the Defect Reports regulations (49 CFR Part 573).

You ask whether the amendments made by sections 4(a) and (c) of Public Law 91-265 took effect on November 28, 1970 or later. Section 4(d) of that law specified, as you note, that these sections take effect 180 days after the enactment of the Act, unless the Secretary of Transportation determined that a later date was in the public interest. No such determination was made, and the sections took effect 180 days after the Act's enactment. However, our computation shows that 180 days after May 22 is November 18, not November 28.

You ask if Owners Lists (49 CFR 573.6), including vehicle identification numbers, can be obtained by NHTSA and transmitted to your organization. The NHTSA would not consider it appropriate to require manufacturers to submit owner's lists to it for purposes not involved in the enforcement of the National Traffic and Motor Vehicle Safety Act. We would not consider the study you wish to perform to be within this purpose.

You also ask if we can furnish you copies of Quarterly Reports (49 CFR 573.5) at least as they relate to cars sold in Puerto Rico. Quarterly reports submitted by manufacturers, except for the production figures submitted pursuant to section 573.5(b), are considered to be public documents and are available for public inspection. Due to the large number of reports we receive, however, we can furnish copies only if the precise reports desired are specified. The reports do not disclose the geographical location of the vehicles involved.

With reference to your request for the latest version of the leaflet, "Motor Vehicle Safety Defect Recall Campaigns," I have enclosed the volume which provides information for the complete year 1971, and a new volume dealing with January-March 1972.

ID: nht72-6.21

Open

DATE: 07/25/72

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Sheller-Globe Corporation

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of June 23, 1972, concerning the Certification and related regulations (49 CFR Parts 567. 568). You indicate in your letter that many school bus bodies are exceeding by small amounts the weight ratings specified for the chassis by the incomplete manufacturer, and that increasing the capability of the chassis results in expenditures which you believe are not justified by the additional safety achieved. You indicate also that you believe that section 567.5 requires the final-stage manufacturer to use the incomplete vehicle ratings for his ratings, except when differing tire sizes are specified in accordance with 567.4(h).

You appear to be misinterpreting the regulations. There is no requirement that a final-stage manufacturer use the ratings provided by the incomplete vehicle manufacturer. The final-stage manufacturer is free to raise them for purposes of certification, as long as the values he chooses are consistent with the definitions of GAWR and GVWR. If he does raise them, however, he can no longer rely on the assurances of the incomplete vehicle manufacturer as to conformity with the standards, but will be responsible, subject to the Vehicle Safety Act's penalties, for (1) conformity of the vehicle with all applicable standards, and (2) ensuring that no safety problem has been created. If the final-stage manufacturer will not assume this responsibility, in our opinion he cannot reasonably maintain that the limitations imposed by the incomplete manufacturer's ratings are unjustified.

In short, you are free to choose and combine your components as you see fit, as long as you use due care to ensure that the vehicle conforms to the standards and contains no safety-related defects. Observing the component manufacturer's maximum load ratings is usually the easiest way to do this.

ID: nht72-6.22

Open

DATE: 02/15/72

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: Wells Manufacturing Corp.

TITLE: FMVSS INTERPRETATION

TEXT: In your letter of February 2 you refer to paragraph S4.5.1 of Motor Vehicle Safety Standard No. 108 and its reference to SAE Recommended Practice J564a, Headlamp Beam Switching, April 1964. You ask "whether there is anything in your Docket related to Rule #108 to bring it up to either J564b or J564c."

Perhaps you misread S4.5.1, but it does allow conformance with J564b as an alternative to J564a. No proposal has been issued requiring or allowing conformance with J564c.

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.