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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 14251 - 14260 of 16514
Interpretations Date
 search results table

ID: nht68-4.12

Open

DATE: 09/10/68

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

TO: National Highway Users Conference

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your letter of August 23, to Mr. George Nield, concerning the compliance of crane carriers and fire engines with Federal Motor Vehicle Safety Standards 103 and 104.

The crane carrier you have described is a "motor vehicle" subject to the provisions of the National Traffic and Motor Vehicle Safety Act of 1966. For purposes of the Federal Motor Vehicle Safety Standards the described crane carrier is classified as a "truck." Although currently Federal Standards 103 and 104 do not apply to trucks both standards, by amendment, issued April 24, 1968, (33 F.R. 6466-69), will be applicable to trucks manufactured on or after January 1, 1969.

Similarly, a fire truck is a "motor vehicle" and a "truck" and subject to all Federal Motor Vehicle Safety Standards applicable to this category of vehicle, including Standards 103 and 104. However, the open cabs found on many fire trucks may make full compliance with Standard 103 impossible. A public docket, Docket No. 24, has been established to receive comments pertaining to the possible classification of fire fighting equipment as a separate vehicle category which might be exempt from certain standards.

ID: nht68-4.13

Open

DATE: 08/27/68

FROM: AUTHOR UNAVAILABLE; E. B. Laskin; NHTSA

TO: Cleveland Public Schools

TITLE: FMVSS INTERPRETATION

TEXT: Your letter of July 3, 1968, addressed to Mr. George C. Nield, of the National Highway Safety Bureau has been forwarded to my office for reply.

The installation of dual controls on driver education cars is not per se in violation of the Federal motor vehicle safety standards. However, the secondary equipment must meet the same safety standards established for the primary controls. The secondary steering column must fulfill the same requirements made for the primary column as set forth in Federal Motor Vehicle Safety Standards Nos. 203 and 204. The installation of an additional foot brake must not affect compliance with Standard No. 105. However, duplicate compliance with the control location and identification requirements of Standard No. 101 is not required since the "driver" of such a vehicle remain the person seated behind the primary controls. For the same reason the "driver" mirror requirements of Standard No. 111 apply only with respect to the person seated at the primary controls.

Changes may be made to original equipment when necessary for installation of secondary controls but none of the standards requirements specified may be eliminated or adversely affected by the alteration.

You may make available copies of this letter to dealers and interested parties.

ID: nht68-4.14

Open

DATE: 09/11/68

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

TO: Meyer Products, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: I regret the delay in responding to your letter of April 23, in which you provided certain certification information and details on your wheeled spreaders.

The wheeled spreaders attached to a towing vehicle are considered motor vehicles under the National Traffic and Motor Vehicle Safety Act of 1966, and have been categorized as "trailers". Federal Motor Vehicle Safety Standard No. 108 is currently the only Standard applicable to trailers, specifically those 80 inches and more in overall width.

This Standard will also apply to trailers of lesserwidth manufactured after December 31, 1968.

Accordingly Meyer Products is required to certify compliance in accordance with section 114 of the Act. I enclose for your guidance copies of the Act, Federal Standard No. 108, and the certification Notice currently in effect.

ID: nht68-4.15

Open

DATE: 09/11/68

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

TO: Ashton Martin Lagonda Ltd.

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your letter of August 27 and your cable of September 5.

You have written me with respect to the possibility of crash-testing an Aston Martin with weight added to the 6 cylinder engine so as to approximate the weight of a V8 engine which you may introduce in the future.

I am puzzled by your opening statement "We are arranging . . . to crash one of our DBS cars . . . on your instructions and as we previously agreed to do . . .." A review of the correspondence between the Federal Highway Administration/National Highway Safety Bureau and Aston Martin Lagonda does not disclose either our instructing you or you agreeing, to crash test any motor vehicle. Generally, this correspondence has concerned the limited production vehicle problem and Public Law 90-283.

Since the demonstration procedure set forth in certain of the standards involves a crash test, an actual crash test seems the best way for a manufacturer to verify conformance with these standards. The standards, however, do not per se require a crash test, and 23 C.F.R. @ 255.11 specifically states that "As approved equivalent may be substituted for any required destructive demonstration procedure."

With respect to your planned test for September 13, our engineers do not view the 40 pound weight differential as significant, and, assuming no further modifications to the DBS, crash testing a 6 or a V8 simulation would be sufficient to demonstrate compliance for the current 6 or projected V8 model.

I understand your concern with the "thought of having to smash cars every time there is a change in specification", but you will have to face this issue every time a new Federal standard appears with a crash demonstration procedures. You may not know of newly issued Standard No. 212 (Windshield Mounting - Passenger Cars), requiring a barrier collision test, and I enclose a copy for your information.

Robert M. O'Mahoney, Esq., Assistant Chief Counsel, US Department of Transportation,

August 27, 1968

We are arranging very shortly to crash one of our DBS cars in 6 cylinder form, on your instructions and as we previously agreed to do, and this will be done during mid September.

As if this is not worrying enough, we are wondering if we may get some concession or help on a further aspect which could cause much financial calamity later on. This is that we may, in the future at a date not yet decided, be in the position to offer an alternative engine capacity of V8 formation in the same chassis.

Basically, this engine will only weigh 40 lbs more than the existing 6 cylinder installation and all mounting points and other fittings will be, to all intents and purposes, identical.

Could you please let me know, as soon as possible, whether or not this alternative will make it necessary for us to crash yet another car; or can it be considered that the minor weight variation would not affect the aspects for which the crash has been organised, i.e. the steering wheel penetration and fuel tank installation.

As a further alternative, might it be possible for us to add this extra weight, in some form to be defined by you, to the existing 6 cylinder engine on our forthcoming crash test in September.

We would be grateful if this particular concession could be made, as quite frankly we had serious thoughts about continueing with the US market when it came to smashing one car, which represents our profit margin for a complete year. The thought of having to smash cars every time there is a change in specification is horrifying and would mean financial penalties which are too heavy for us to bear.

Could I please trouble you for a very prompt reply in view of the possibility of the extra weight 'concession' we have requested to simulate the V8 unit, and the time needed to organise this prior to the crash test of the 6 cylinder car.

D.C. Gerston. Director of Engineering ASTON MARTIN LAGONDA LTD.

ID: nht68-4.16

Open

DATE: 09/16/68

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

TO: Messrs. O'Donohue and O'Connor

TITLE: FMVSR INTERPRETATION

TEXT: In your letter of August 15 you ask for a copy of regulations issued under the National Traffic and Motor Vehicle Safety Act of 1966 which might apply to "a small refuse-carrying three-wheeled vehicle" which is being designed by one of your clients.

I enclose a copy of all Federal Motor Vehicle Safety Standards which have been issued to date. You will note in 23 C.F.R. @ 255.3(b) that the definitions of "truck" and "motorcycle" or "motor driven cycle" appear to apply to the vehicle you have described. In order to make a definite classification we need more information such as 'a photograph of the vehicle and a technical specification sheet'.

However, if the vehicle is classified as a "truck", 23 C.F.R. @ 255.7(a) provides that the Federal Standards will not apply if its curb weight is 1,000 pounds or less. If the vehicle is classified as a "motorcycle" or "motor driven cycle", Federal Standard No. 108 effective January 1, 1969, will be the only Standard applicable to this category of vehicle.

If there is any further assistance I can give you I shall be happy to do so.

O'DONOHOE AND O'CONNOR

August 15, 1968

National Highway Safety Bureau

It is our understanding that under the President's Executive Order of June 6, 1967, your Bureau is charged with the carrying out of the principles of the Highway Safety Act.

This firm represents a small local corporation which is engaged in the design for marketing of a small refuse-carrying three-wheeled vehicle, to be primarily used in combination with a larger packer truck.

Could you please forward to the undersigned copies of such bulletins or regulations as you have promulgaged with reference to required safety features in this particular type of vehicle.

The vehicle will be three wheeled, operate with hydrostatic drive, and will have a dump box at the front. As stated above, it's main purpose will be to pick up from trash cans in alley ways and up driveways and then to deposit its load when full in the larger packer truck.

We will be glad to supply added details for your use in determining what regulations would be applicable;but frankly, right now, having just read the bare bones of the statute, I am at a loss to know what you will need to proceed.

We would appreciate it if you would send us such materials as you have on hand.

James E. O'Donohoe

ID: nht68-4.17

Open

DATE: 09/17/68

FROM: AUTHOR UNAVAILABLE; William Haddon, Jr.; NHTSA

TO: Chrysler Corporation

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your letter of September 11, 1968, to Mr. J.E. Leysath of this Bureau, concerning the Chrysler Super Lite which you intend to offer as an optional supplemental light on some of the Chrysler 1969 car lines.

You are correct in your understanding that a supplemental light of this type is not required by Federal Motor Vehicle Safety Standard No. 108. Standard No. 108 does, however, specify, in Paragraph S3.1.2, that no additional lamp, reflective device, or associated equipmont shall be installed if it impairs the effectiveness of the required equipment.

On the basis of our review of your technical literature on the Super Lite and our observation of limited field demonstrations of the light, it does not appear that the Super Lite will impair the effectiveness of the lighting equipment required by Standard No. 108. It should be noted, however, that, while the incorporation of this lamp in your 1969 automobiles would not be precluded by the Federal Standard, the various States may interpose restrictions as to this lamp.

With respect to the requirements of Standard No. 108, I must point out that this Bureau does not issue approvals on items of lighting equipment or on vehicle designs incorporating this equipment. Therefore, the above comments are for your information only and in no way relieve the vehicle manufacturer from his responsibility for certifying that the assembled vehicle meets the requirements of the standard.

ID: nht71-1.38

Open

DATE: 02/10/71

FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA

TO: Kelly Springfield Tire Company

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of February 2, 1971, concerning Part 574 - Tire Identification and Record Keeping regulations and to confirm that the date code may be placed at the end of the tire identification number by means of a screw as depicted in the sketch attached to your letter.

ID: nht71-1.39

Open

DATE: 02/18/71

FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA

TO: Toyo Tire (U.S.A.) Corporation

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of February 2, 1971, to Mr. Casanova concerning Part 574 - Tire Identification and Record Keeping.

Adding a group of numbers consisting of three-digits to the tire identification number is not permitted under the regulation because the additional numbers 99:(Illegible Word) be too easily confused with the tire identification number.

You are not prohibited, however, from placing the additional three-digit number elsewhere on the tire in an area where it would not be confused with the required tire identification number. Anywhere further than six inches would be far enough to avoid confusion.

ID: nht71-1.4

Open

DATE: 01/01/71 EST.

FROM: Robert L. Carter; NHTSA

TO: JEEP Corporation

TITLE: FMVSS INTERPRETATION

TEXT: On June 16, 1971, you and Mr. William Fleming of American Motors met with representatives of NHTSA and pointed out that the March 4, 1971, revisions of Standard No. 210 (36 F.R. 4291) had created a situation where seat belt anchorages for side-facing seats of multipurpose passenger vehicles would have to meet strength requirements only for the six-month period from July 1, 1971, to January 1, 1972. This occurred because the March 4 notice, which basically extended the existing standard for passenger cars to other types of vehicles as of July 1, 1972, did not have the exemption for side-facing seat belt anchorages that is contained in the revised standard that goes into effect on January 1, 1972.

The failure to exempt side-facing seats from the anchorage test requirements for the six-month period ending January 1, 1972, was inadvertent. A Federal Register notice will be issued shortly amending Standard No. 210 to correct this discrepancy. I am sending you this letter, which will be placed in the public files, in advance of the notice as an extraordinary procedure in light of the time period involved, to confirm that your vehicles need not meet the strength requirements for seat belt anchorages for side-facing seats apparently contained in Standard No. 210.

ID: nht71-1.40

Open

DATE: 05/21/71

FROM: Lawrence R. Schneider; NHTSA

TO: Jack Lewis; Legislative Assistant, U.S. Senate

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your telephone conversation of May 19, 1971 with a member of this office concerning Pert 574 - Tire Identification and Record Keeping.

In your conversation you asked what the position of the National Highway Traffic Safety Administration would be if a retreader could establish he was unable to obtain, by May 22, 1971, the effective date of the regulation, the necessary tin plate for placing the required tire identification number on his retreaded tires.

Of course, each case would be considered individually, but if a retreader could demonstrate that good faith attempts had been made to obtain the tin plate by May 22, 1971, and due to circumstances beyond his control he was unable to mark tires manufactured after May 22, 1971 with the required identification number, the National Highway Traffic Safety Administration would not take enforcement section against the retreader.

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.