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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 13861 - 13870 of 16490
Interpretations Date

ID: nht69-2.36

Open

DATE: 12/23/69

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

TO: Blue Bird Body Company

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your letter of December 9, 1969, providing additional information on the school bus lighting system as described in your previous letter of November 14, 1969.

Paragraph S3.1.2 of Federal Motor Vehicle Safety Standard No. 108 specifies that, The additional lamp, reflective device, and associated equipment shall be installed if it impairs the effectiveness of the required equipment." The system of front stop lamps as described in your letters, i.e., two non-flashing amber lamps of the same size as and located in line with the two red school bus signal lamps, and actuated by the foot brake only, would not appear to impair the effectiveness of the lighting equipment required by Standard No. 108. It should be noted, however, that, while incorporation of this system in school buses would not be precluded by Standard No. 108, the various States may interpose restrictions as to such system. I would suggest, therefore, that you review the applicable State regulations before initiating installation of the system.

ID: nht71-4.10

Open

DATE: 09/13/71

FROM: AUTHOR UNAVAILABLE; L. R. Schneider; NHTSA

TO: Ray. C. Ellsworth Ranches

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your letter of September 2 inquiring whether your braking system hydraulic valve "is in conformity with the Federal Dual Braking Regulations now in effect."

Federal Motor Vehicle Safety Standard No. 105, Hydraulic Service Brake, Emergency Brake, and Parking Brake Systems, applies to passenger cars, and not to individual items of motor vehicle equipment incorporated in a hydraulic brake system. Thus, there is no Federal Standard to which your valve must conform. If the valve is installed as original equipment in a passenger car, it is the vehicle that would be required to conform to the performance requirements of Standard No. 105.

I have noted your comment that the valve is to be tested on braking systems for military vehicles. You may be interested to know that Federal Motor Vehicle Safety Standards, including No. 105, do not apply to vehicles manufactured for and sold to the Armed Forces of the United States.

ID: nht90-3.42

Open

TYPE: Interpretation-NHTSA

DATE: August 1, 1990

FROM: Kathleen DeMeter -- Assistant Chief Counsel for General Law

TO: William F. Canever -- Office of the General Counsel, Ford Motor Company

TITLE: None

ATTACHMT: Attached to letter dated 10-22-90 from P.J. Rice to W.F. Canever (A36; Sec. 501(8), Sec. 501(12); Also attached to letter dated 6-1-90 from W.F. Canever to S.P. Wood

TEXT:

This is in response to your two letters to Stephen P. Wood, as NHTSA's Acting Chief Counsel, dated June 1, 1990, regarding Corporate Average Fuel Economy. Each of these letters is marked "Privileged and Confidential," but neither one identifies the port ions for which confidentiality is claimed, or includes justification or an affidavit in support of Ford's request for confidential treatment.

On July 13, 1990, in a telephone conversation with Ms. Heidi L. Coleman of my staff, you indicated that these markings were made inadvertently, and that Ford does not seek confidential treatment for the contents of these letters. This information will, therefore, not be protected. Thank you for your cooperation in this matter.

ID: 15303.ztv

Open

Mr. David Hutton
Intereurope Regulations Ltd
21-23 East Street
Hareham
Hampshire PO16 DB4
England

Dear Mr. Hutton:

This replies to your FAX of April 23, 1997, to Richard Van Iderstine of this agency, asking whether there is an error in paragraph S8.9 of Federal Motor Vehicle Safety Standard No. 108, as it appears on page 247 of Title 49 Parts 400 to 999 of the Code of Federal Regulations revised as of October 1, 1996.

You are quite correct. The final sentence of S8.9 in the October 1, 1996, edition begins with the phrase "Distance 'A'". This is an error. The sentence beginning "Distance 'A'" should be the final sentence of S9 as amended on November 28, 1995. The 1996 volume mistakenly placed this amendment in S8.9.

Thank you for calling this matter to our attention. We have arranged for a correction in the next edition of Title 49 Parts 400 to 999.

Sincerely,
John Womack
Acting Chief Counsel
ref:108
d.6/24/97

1997

ID: nht70-1.40

Open

DATE: 02/04/70

FROM: AUTHOR UNAVAILABLE; Douglas W. Toms; NHTSA

TO: Norton Villiers Corporation

TITLE: FMVSR INTERPRETATION

TEXT: Thank you for your letter of January 22, 1970, enclosing ten copies of the Consumer Information for motorcycles produced by Norton Villiers Corporation.

Your submittal has on its face eliminated the problems that were called to your attention in our letter of January 9. The form in which the information is presented deviates, however, from the form prescribed by the regulations, sections 575.101 and 106. The most significant deviation is the omission of the explanatory statements that are required for both types of information. The figures included with each section of the regulations should be followed closely in your presentation of the information to purchasers.

Please let us know if we can be of further assistance.

ID: nht72-5.22

Open

DATE: 02/07/72

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Downs-Clark

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of December 30, 1971, concerning whether you must comply with the Certification regulations (49 CFR Part 567) in cases where you "re-barrel" or "re-deck" trailers. You describe these processes as installing a new tank (re-barreling) or platform deck (re-decking) on a used trailer under construction furnished by your customer, which includes axles, tires, wheels, springs, hangers, and internal brake assemblies, in serviceable condition.

You are not required to certify these vehicles as they are manufactured on used chassis and are considered by this agency to be used vehicles under section 108(b)(1) of the National Traffic and Motor Vehicle Safety Act (15 U.S.C. @ 1397(b)(1)).

We are pleased to be of assistance.

ID: nht69-2.43

Open

DATE: 12/11/69

FROM: AUTHOR UNAVAILABLE; Robert Brenner; NHTSA

TO: Mercedes-Benz of North America Inc.

TITLE: FMVSR INTERPRETATION

TEXT: RE: CONSUMER INFORMATION

We have received your submittal of consumer information in response to the requirements of 49 CFR Part 375. The regulation requires that manufacturers submit their information to the Administrator 30 days in advance of the time it is made available to prospective purchasers. Since we have not required that this advance submittal be in the same form as that given to purchasers, the following comments are only advisory in nature. There is one respect, however, in which the information, if supplied in this form to prospective purchasers, would not satisfy the requirements of the regulations.

The Consumer Information section on Vehicle Stopping Distance, 49 CFR @ 375.101, specifics that the information presented shall contain "the most adverse combination of maximum or lightly loaded vehicle weight and complete loss of braking in any one of the vehicle brake subsystems." In your submittal, you have presented information for failures in each of the front and rear subsystems, instead of selecting the most adverse combination of weights and system failures. This is likely to confuse consumers attempting to compare vehicles of different manufacturers, and fails to satisfy the requirement that the information shall be submitted "in essentially the form illustrated in Figure 1" of @ 375.101.

We will be glad to answer any questions that you may have with respect to the requirements of these or other motor vehicle safety regulations and standards.

ID: nht79-1.32

Open

DATE: 02/22/79

FROM: AUTHOR UNAVAILABLE; John Womack; NHTSA

TO: Pennsylvania Notaries

TITLE: FMVSR INTERPRETATION

TEXT:

22 FEB 1979

S. B. Aronson Pennsylvania Notaries 625 Stanwix Street Pittsburgh, Pennsylvania 15222

Dear Mr. Aronson:

This is in response to your letter of January 4, 1979, requesting our opinion as to whether a rubber stamp which contains the odometer information on the newest Pennsylvania title could be applied to older titles in lieu of having a separate form attached.

There are no legal bars to your recommendation. In fact, the stamp you recommend makes more sense than a separate form. A separate form can be removed and replaced with another sheet. A stamp cannot be so abused.

We appreciate and support your recommendation.

Sincerely,

John Womack Assistant Chief Counsel

ID: nht71-3.47

Open

DATE: 07/21/71

FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA

TO: Erie Strayer Company

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of June 15, 1971, inquiring if a mobile concrete batch plant is considered a motor vehicle for purposes of the Tire Identification and Record Keeping Regulation (49 CFR 574).

The Erie Strayer's Mobile Combo-100 illustrated in your enclosed brochure is considered a motor vehicle. Enclosed is a letter dated April 20, 1970, signed by Secretary Volpe which sets forth the reasoning behind this determination.

As a motor vehicle manufacturer, you are required under Part 574, to maintain records of the name and address of the first purchaser for purposes other than resale of your vehicle along with a record of the tires shipped on or in your vehicles.

If we can be of further assistance, please feel free to write.

ENC.

ID: nht91-1.1

Open

DATE: 01/01/91 EST

FROM: Jessie M. Flautt

TO: Steve Kratzske -- NHTSA Office

TITLE: None

ATTACHMT: Attached to letter dated 3-26-91 from Paul Jackson Rice to Jessie M. Flautt (A37; Std. 202; VSA 108(a)(2)(4))

TEXT:

I am writing to your department to obtain authorization to reduce the size of the headrests in a 1991 automobile; These reductions would still meet the federal standards set in 1987. I am not able to drive a 1991 car due to the increased length and width of the headrests in the past few years. The newer cars are designed for an average man with average vision: however, I am under five feet-two and an legally blind in one eye. Therefore, I cannot find a car that does not impede my field of vision. Consequently, my driving safety and that of drivers and passengers in other cars is in jeopardy as I have a limited view of side and rear objects.

I would be the sole driver of the car and would thus not be endangering anyone else by a reduction of the headrests: in fact, I would be greatly improving my own safety as well as that of persons in other vehicles if I were allowed to increase my field of vision by reducing the size of the headrests.

I apppreciate the time and interest you expended in speaking to me on the telephone. It is a wonderful feeling to know that we can indeed reach a helpful person in our huge goverment organization.

(Stetson's Auto Shops, 7414 Ashcroft, Houston, Texas, would be doing this work.)

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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