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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 15371 - 15380 of 16490
Interpretations Date

ID: nht91-5.7

Open

DATE: July 30, 1991

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: Debby Funk

TITLE: None

ATTACHMT: Attached to letter dated 7-5-91 from Debby Funk to Paul Jackson Rice

TEXT:

This responds to your letter of July 5, 1991, as a followup to my letter of June 25. You have asked whether "it would be illegal for the owner of a vehicle that has a center highmounted stop lamp to install an additional rear window brake light? (anywhere in the back window?)"

The answer is that it would not be illegal under Federal law for a vehicle owner to install an additional stop lamp anywhere in the back window, providing that all modifications were performed by the owner. However, the legality of the modification would still be subject to State law.

You have also asked "What is F.M.V.S.S. 108?" That is Federal Motor Vehicle Safety Standard No. 108 Lamps, Reflective Devices and Associated Equipment. It can be found in Title 49 Code of Federal Regulations, as 571.108.

If you have further questions, please don't hesitate to write.

ID: aiam4664

Open
Mr. Stephen R. Darling Presvac Systems (Burlington) Ltd. 4131 Morris Drive Burlington, Ontario, Canada L7L 5L5; Mr. Stephen R. Darling Presvac Systems (Burlington) Ltd. 4131 Morris Drive Burlington
Ontario
Canada L7L 5L5;

"Dear Mr. Darling: This responds to your inquiry about an amendment t 49 CFR Part 575, Consumer Information Regulations, requiring vehicle manufacturers to include information in the owner's manual (or on a one-page document if there is no owner's manual) about the National Highway Traffic Safety Administration's Auto Safety Hotline and its defect investigation and remedy and recall authority. (54 FR 48745, November 27, 1989, copy enclosed). I apologize for the delay in our response. You explained that you are involved in three types of activities: the manufacture of liquid cargo vessel trailers, the fabrication of liquid cargo tanks, and the installation of these tanks onto existing or modified truck chassis. While you acknowledged your obligation to furnish the consumer information for the trailers you manufacture, you were uncertain about your responsibilities to furnish this information for the liquid cargo tanks you fabricate and install. You asked whether you are required to supply the specified consumer information in these instances. Your questions are responded to below. Section 575.6(a)(2)(i), as amended, provides that 'At the time a motor vehicle manufactured on or after September 1, 1990 is delivered to the first purchaser for purposes other than resale, the manufacturer shall provide to the purchaser' a specified statement about this agency's activities related to motor vehicle defects. Among other things, the specified statement indicates that if an owner believes the vehicle has a defect which could cause a crash or an injury or death, the owner should inform NHTSA in addition to notifying the manufacturer. The manufacturer's name must be indicated in the statement. In responding to your questions, I note that section 575.6(a)(2)(i) applies to manufacturers of new motor vehicles. As a manufacturer of trailers, you are, of course, responsible for providing the specified consumer information to the first purchaser of such trailers (for purposes other than resale). On the other hand, in situations where you are not a vehicle manufacturer, e.g., where you may be installing tanks on used motor vehicles, the requirements would not apply. Your letter also raises the issue of how section 575.6(a)(2)(i) applies in situations where there is more than one manufacturer of a motor vehicle, i.e., where vehicles are manufactured in two or more stages. While it is not clear from your letter, it is possible that you may be a final stage manufacturer under 49 CFR Part 568. (The term 'final stage manufacturer' is defined in 49 CFR Part 568.3.) As indicated above, section 575.6(a)(2)(i) specifies that, at the time a vehicle is delivered to the first purchaser for purposes other than resale, 'the manufacturer' must provide specified consumer information to the purchaser. Since the regulation requires information to be provided at the time of first consumer sale, we construe it to require the manufacturer of the completed vehicle, i.e., the final stage manufacturer, to meet this requirement. As a general rule, the final stage manufacturer is the manufacturer that has the closest relationship to the dealer which sells the vehicle to the consumer. It is also the manufacturer that the consumer will typically contact first in the event of problems. I hope this information is helpful. If you have any further questions, please feel free to contact Marvin Shaw of my staff at this address or by telephone at (202) 366-2992. Sincerely, Paul Jackson Rice Chief Counsel Enclosures";

ID: nht89-1.15

Open

TYPE: INTERPRETATION-NHTSA

DATE: 02/04/89

FROM: LEON E. PANETTA -- CONGRESS

TO: ERIKA JONES -- CHIEF COUNSEL NATL. HWY. TRAFFIC SAFETY ADMIN.

TITLE: NONE

ATTACHMT: ATTACHED TO LETTER DATED 04/17/89 FROM ERIKA Z. JONES -- NHTSA TO LEON E. PANETTA, REDBOOK A33(2), STANDARD 111

TEXT: Dear Ms. Jones:

Recently one of my constituents contacted me about a matter which falls under your agency's jurisdiction. Specifically, Mr. Botelho, a professional driver, was concerned about the requirements for having a mirror on the right side of his vehicle. He wa nts to know whether there is a law requiring mirrors on the right side and if those mirrors must be made convex.

Mr. Botelho feels that it is important for mirrors to portray an accurate image and not cause an object to appear further away than they really are. In my constituent's opinion, the mirrors are hazardous and confusing.

I would appreciate your office clarifying this requirement and its applications to professional drivers in California. I would like further information on the background of this requirement and the reasons for its implementation.

I would appreciate your agency responding in writing to me directly.

I look forward to hearing from you soon.

Sincerely,

ID: 9792

Open

Eric T. Stewart, Engineering Manager
Mid Bus
3555 St. Johns Road
P.O. Box 1985
Lima, OH 45802-1985

Dear Mr. Stewart:

This responds to your letter of March 17, 1994, regarding a final rule published November 2, 1992 (57 FR 49413) amending Standard No. 217, Bus Emergency Exits and Window Retention and Release. You requested clarification of the width requirement in S5.5.3(c) for retroreflective tape.

You are correct that there was a discrepancy concerning the size of the tape caused by the metric conversion in the final rule. Enclosed is a copy of a July 7, 1993 letter to Mr. Thomas D. Turner of the Blue Bird Body Company which discusses this issue. As explained in that letter, we plan to issue a correction notice of the November 2, 1992 rule that would specify a minimum size of 2.5 cm for the tape. Until the correction is issued, we will not take enforcement measures regarding tape size against a manufacturer who uses 1 inch wide retroreflective tape.

I hope you find this information helpful. If you have any other questions, please contact us at this address or by phone at (202) 366-2992.

Sincerely,

John Womack Acting Chief Counsel

Enclosure

ref:217 d:4/l/94

1970

ID: nht94-6.23

Open

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

ID: nht95-6.45

Open

TYPE: INTERPRETATION-NHTSA

DATE: September 18, 1995

FROM: Ben Ray

TO: John Womack

TITLE: NONE

ATTACHMT: ATTACHED TO 11/28/95 LETTER FROM Samuel J. Dubbin to Ben Ray (A43; Std. 121; Part 571.7)

TEXT: Dear Mr. Womack,

This letter is in regards to brake adjusters for log trailers. I am currently building log trailers for resale. These trailers are used mostly in the woods transporting logs from the woods to the mills. I am using used axles under them. These used axles already have regular brake adjusters on there when I buy them. What I would like is some paperwork saying if this is alright to use these regular brake adjusters instead of automatic adjusters. I was referred to you by Richard Carter, (202-366-5274). Mr. Carter said there was a fine line in regards to which one to use because of the fact that the axles that I use are used. He also said being that the trailer is not considered new, that I could use a regular brake adjuster. I would really appreciate it if you could send me some paperwork stating that it is alright to use these regular brake adjusters. If you should have any questions, please call me at home, 901-925-2727 or work, 901-925-1893.

Sincerely,

ID: nht73-4.2

Open

DATE: 04/04/73

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Yuma Tire & Recapping Inc.

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of February 28, 1973, requesting a detailed explanation of what you must do to conform to Motor Vehicle Safety Standard No. 117, "Retreaded Pneumatic Tires". You also ask whether there are record keeping requirements, such as to maintain the name and address of customers to whom tires are sold.

There are specific requirements for retreaders and their dealers to record and maintain the name and address of each tire purchaser. This is done through the use of a code number molded or branded onto each tire. These requirements (49 CFR Part 574, copy enclosed) have been in effect since May 22, 1971.

We have enclosed a copy of Standard No. 117. We regret that we cannot provide a detailed explanation of these requirements as you request. We refer you to either private counsel or to one of the many associations of retreaders whom we understand can assist you in implementing the standard. If after reading the standard you have questions of a specific nature regarding its provisions, we will respond to them.

ENC.

ID: nht73-4.34

Open

DATE: 07/19/73

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

TO: Kysor of Cadillac

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of June 22, 1973, concerning the applicability of section S5.1.4, Pressure gauge, of Standard No. 121, to an electronic gauge that displays the air pressure under normal conditions only when the driver pushes a switch but that provides continuous display at pressures below 70 p.s.i.

Section S5.1.4 requires a pressure gauge to be "readily visible." Used in this context, "readily visible" means visible whenever the driver wants to see it. It does not mean that the air pressure level should be continuously visible. As we understand your system, the driver could determine the air pressure at any time by pushing the "air pressure" button. We have concluded that this operation satisfies the intent of S5.1.4 and that your system would be permissable under that section.

The low pressure warning signal is required by section S5.1.5 and must be separate from the pressure gauge. You state that you provide a flashing red light and an audible alarm, in addition to providing continuous readout of air pressure below 60 p.s.i. This would appear to conform to S5.1.5.

ID: nht93-4.15

Open

DATE: June 2, 1993

FROM: Eddie Bernice Johnson -- Member of Congress, 30th District Texas, U.S. House of Representatives

TO: Art Neill -- Division Chief, Office of Vehicle Safety Standards, NHTSA

TITLE: None

ATTACHMT: Attached to letter dated 6-28-93 from John Womack to Eddie Bernice Johnson (A41; Part 571).

TEXT: Dr. Way recently contacted my office concerning the resale of military vehicles for civilian use. The enclosed letter from Dr. Way should more clearly state issue.

I would appreciate having the benefit of your review and consideration of Dr. Way's request so that I might better prepare a response. Please respond to my Dallas office at the District address above, where this case has been assigned to my staff assistant, Scott Rule.

Thank you for your attention in this matter.

April 29, 1993

Congressman Martin Frost 400 S. Zang Dallas, TX 75208

Dear Congressman:

As a concerned citizen of Dallas, Texas, I want to inform you of something I have been alerted to. I called to find out about the purchase of used military jeeps for possible use as a vehicle on my ranch. We would use this vehicle as an off-the-road vehicle and occasionally as a vehicle to travel back and forth to town. Upon contacting the Department of Defense at 800-222-3767, which is a recorded message describing the Department of Defense surplus sales, it states that the military jeep M-151 is a type of vehicle that for some reason the Department o+ Transportation has deemed unsafe to be used on public roads. Therefore, the military vehicles are not sold, but are destroyed by crushing. I called Carswell AFB and asked the surplus sales department there about sale of the jeeps. They gave me the same information, that they do not sell military Jeeps, and they are destroyed for safety reasons.

I find this very unusual, because if they are found to be unsafe on our roads, how can we consider these vehicles safe for use by military personnel? I was in the military and rode in these vehicles on and off the road, and they were very safe depending on who was driving.

I would like you to investigate this situation, because I feel this is another waste of materials by the government. These vehicles could be sold and used by civilians after they have completed their military use. I think this is a situation that needs to be rectified.

Sincerely yours,

Bill V. Way, D.O. Concerned Citizen

ID: nht94-7.12

Open

DATE: April 1, 1994

FROM: John Womack -- Acting Chief Counsel, NHTSA

TO: Eric T. Stewart -- Engineering Manager, Mid Bus (Lima, OH)

TITLE: None

ATTACHMT: Attached to letter dated 7/7/93 from John Womack to Thomas D. Turner; Also attached to letter dated 3/17/94 from Eric T. Stewart to Office of Chief Counsel, NHTSA (OCC 9792)

TEXT:

This responds to your letter of March 17, 1994, regarding a final rule published November 2, 1992 (57 FR 49413) amending Standard No. 217, Bus Emergency Exits and Window Retention and Release. You requested clarification of the width requirement in S5.5.3(c) for retroreflective tape.

You are correct that there was a discrepancy concerning the size of the tape caused by the metric conversion in the final rule. Enclosed is a copy of a July 7, 1993 letter to Mr. Thomas D. Turner of the Blue Bird Body Company which discusses this issue. As explained in that letter, we plan to issue a correction notice of the November 2, 1992 rule that would specify a minimum size of 2.5 cm for the tape. Until the correction is issued, we will not take enforcement measures regarding tape size against a manufacturer who uses 1 inch wide retroreflective tape.

I hope you find this information helpful. If you have any other questions, please contact us at this address or by phone at (202) 366-2992.

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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