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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 12801 - 12810 of 16510
Interpretations Date
 search results table

ID: nht73-2.27

Open

DATE: 04/04/73

FROM: RICHARD B. DYSON -- NHTSA ASSISTANT CHIEF COUNSEL

TO: PAUL K. WILSON -- TRUCK TRAILER MANUFACTURERS ASSOCIATION

TITLE: NONE

ATTACHMT: ATTACHED TO LETTER DATED 03/10/81, FROM FRANK BERNDT -- NHTSA TO DONALD W. VIERIMAA, NOA 30, REDBOOK A22, STANDARD 108; LETTER DATED 02/09/81 FROM DONALD W. VIERIMAA TO FRANK BERNDT -- NHTSA, EXCLUSION OF THE TOWBAR OF A PERMANENT TRAILER DOLLY FROM THE FMVSS 108 LENGTH CRITERIA

TEXT: Dear Mr. Wilson:

This is in reply to your letter of March 19, 1973, asking whether a towbar dolly must be included in determining the overall length of semitrailers for compliance with Federal Motor Vehicle Safety Standard No. 108.

The answer is no. Standard No. 108 is a manufacturing standard, and semitrailers are not manufactured with dollies attached. 49 CFR S390.7, to which you refer, is a definition of the Bureau of Motor Carrier Safety which regulates the operation of certain motor vehicles, and since trailers often use converter dollies, it is understandable that that agency would deem a trailer with a dolly a "full trailer."

Yours truly,

[DIAGRAMS OMITTED]

ID: nht73-2.28

Open

DATE: 03/30/73

FROM: GALE S. MOLOVINSKY -- ATTORNEY, LEGAL DEPARTMENT NATIONAL AUTOMOBILE DEALER ASSOCIATION

TO: LAUREN SNYDER -- CHIEF COUNSEL NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION

COPYEE: RICHARD B. DYSON; FRANCIS H. BURNS; ED OGLE; JAMES R. GARFIELD

ATTACHMT: LETTER DATED 05/02/73 FROM JAMES E. WILSON -- NHTSA TO GALE S. MOLOVINSKY; N40-30; SECTION 108

TEXT: Dear Mr. Snyder:

It has been brought to our attention that the Veterans Administration regulations pertaining to veterans requiring adaptive equipment on automobiles financed by the VA pursuant to VA Form 21-4502 compel dealers to furnish the car suitably modified before the veteran is permitted to accept delivery.

Since disabled veterans may require prosthetic service, the VA is concerned that no veteran accept delivery of a vehicle that he cannot operate. DOT regulations, however, prohibit dealers from modifying vehicles where safety standards may be affected. Because of the nature of the disability, veterans frequently need radical alterations of the accelerator, steering column, brake pedals, seat chassis and dashboard. A car which has been modified for an individual who has lost both feet or both hands, for example, could be considered unsafe because it would be unrecognizable and undriveable for an individual without knowledge of such adaptive equipment. Furthermore, such modifications might affect existing structural equipment required by the safety standards.

Dealers are uncertain as to whether or not safety standards are effected and therefore reluctant to unilaterally make equipment changes which might be in violation of the law. Although the dealer wishes to assist the veteran in securing operable, reliable transportation, he is caught between the conflicting policy directives of DOT and the VA. Of course, the disabled veteran suffers the most. I have discussed this problem with the VA and Mr. Dyson of your office and a consensus has developed that perhaps NHTSA could clarify policy to permit dealers to modify cars prior to delivery when ordered for specific physically impaired customers.

2

NADA supports DOT's efforts on behalf of our customers to insure that motor vehicles contain as many safety features as needed to reduce the possibilities of injury. It is not NADA's intention to seek modification or relaxation of any safety standard, but merely to affect a process wherein dealers may render their services to those Americans requiring adaptive equipment without fearing the consequences of violating the law as it now stands.

Mr. Burns of the VA's General Counsel's office and others at that agency are also eager to cooperate on this matter.

I look forward to cooperating with your office toward a speedy resolution of this situation.

Sincerely yours,

ID: nht73-2.29

Open

DATE: 10/15/73

FROM: RICHARD B. DYSON -- NHTSA ASSISTANT CHIEF COUNSEL

TO: DAVID J. HUMPHREYS -- RVI WASHINGTON COUNSEL RECREATIONAL VEHICLE INSTITUTE, INC.

TITLE: N40-30: SCF; STANDARD 302

TEXT: Dear Mr. Humphreys:

This is in reply to your letter of April 27, 1973, regarding the application of Motor Vehicle Safety Standard No. 302, "Flammability of Interior Materials", to mattress covers. You ask whether "mattress covers", listed under Paragraph S4.1 of the standard, includes a cover "that is used generally to enclose a mattress for cleanliness or sanitary purposes or only the ticking which encloses the mattress filling or core or both items . . ."

We consider that mattress ticking and a cover enclosing a mattress for sanitary purposes are both "mattress covers" within the meaning of the standard, and both items must meet the requirements of the standard.

Thank you for sending us the copy of your memorandum, "Department of Commerce Standards Issued Under the Flammable Fabrics Act."

Yours truly,

ID: nht73-2.3

Open

DATE: AUGUST 17, 1973

FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA

TO: ATTORNEY GENERAL'S OFC. -- RICHMOND, VA.

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your letter of July 31, 1973, concerning the effect of our Standard 208 on State laws requiring vehicles to be equipped with seat belts.

Section 103(d) of the National Traffic and Motor Vehicle Safety Act, 15 U.S.C. 1392(d), reads:

Whenever a Federal motor vehicle safety standard established under this title is in effect, no State or political subdivision of a State shall have any authority either to establish, or to continue in effect, with respect to any motor vehicle or item of motor vehicle equipment any safety standard applicable to the same aspect of performance of such vehicle or item of equipment which is not identical to the Federal standard. . . .

Standard 208 (49 CFR 571.208) permits passenger cars to be manufactured under any one of several options for occupant crash protection. One of these options is "complete passive protection", under which the vehicle must undergo a series of rigorous crash tests, in which instrumented dummies without belt restraints show force levels that would not create serious injury to a human occupant in most cases. Manufacturers are not required by the standard to have seat belts at any position that meets the requirements of this option.

The NHTSA considers that Section 103(d), quoted above, clearly renders void any State laws or regulations to the extent that they would require a vehicle to be equipped with seat belts at seating positions that comply with the complete passive protection option. Any State requirements that are not "identical" to these of an applicable standard are preempted by that section, under basic Constitutional principles of the supremacy of Federal law.

I am enclosing some information on the efficacy of air cushion restraints, as you requested. We are pleased to be of assistance.

Sincerely,

Enclosure

ATTACH.

OFFICE OF THE ATTORNEY GENERAL

July 31, 1973

Lawrence R. Schneider, Esquire -- Chief Counsel, NHTSA

Dear Mr. Schneider: This is in reference to a recent telephone conversation with Mr. Dick Dyson in respect to the projected program of General Motors Corporation to market one hundred thousand automobiles equipped with "air bags" instead of safety belts.

As you know, a number of states have statutes requiring that all passenger cars or other motor vehicles registered after certain dates shall be equipped with safety belts. Chapter 357, Acts of Assembly of 1962, embodied in @ 46.1-309.1, Code of Virginia (1950), as amended, requires all motor vehicles registered in this State designed and licensed primarily for private passenger vehicular transportation on the public highways, and manufactured for the year 1963 or subsequent years, to be equipped with safety lap belts or a combination of lap belts and shoulder straps or harnesses. In 1968 an amendment was added which requires that "Passenger motor vehicles registered in this State and manufactured after January 1, 1968, shall be equipped with lap belts or a combination of lap belts and shoulder straps or harnesses as required to be installed at the time of manufacture by the Federal Department of Transportation."

In view of the last quoted amendment, it seems clear that the safety belt requirements for such vehicles in this State are dependent upon the requirements of the Federal Department of Transportation. Further, I am aware of the premise of over-riding power in the case of conflict between State and Federal law. For the benefit of this and other states in further clarifying this situation, however, it is requested that you render an opinion on the question of validity of State laws requiring that vehicles be equipped with safety belts. In this, your attention is directed to Public Law 89-563, 89th Congress, S. 3005, September 9, 1966, and Motor Vehicle Safety Standard No. 208. Any additional information on the efficacy of "air bags" as opposed to safety belts would be most helpful.

Respectfully yours,

A. R. Woodroof -- Assistant Attorney General

ID: nht73-2.30

Open

DATE: 12/26/73

FROM: DARROLL P. YOUNG -- PRESIDENT YOUNG'S MACHINE COMPANY

TO: OFFICE OF CHIEF COUNCIL NHTSA U.S. DEPT OF TRANSPORTATION

TITLE: NONE

ATTACHMT: ATTACHED TO LETTER DATED 1/8/74 FROM RICHARD B. DVSON -- NHTSA TO DARRELL P. YOUNG -- PRESIDENT YOUNG'S MACHINE COMPANY

TEXT: We are manufacturers of Diesel powered underground mine trucks. These vehicles utilize truck differential having hydraulic brakes. Most of the vehicles have two wheel drive, and in such cases have brakes only on the driving axles.

The maximum speed attainable under full power is approximately 12 miles per hour. The vehicles are not designed to operate on highways or public roads.

Kindly supply us with regulations number 121 and 105A in order that we may determine our responsibility as regards compliance with the above regulations.

Thank you very much.

Very truly yours,

ID: nht73-2.31

Open

DATE: 08/17/73

FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA

TO: Trelleboros Gummifabriks Aktiebolag

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of May 9, 1973, in which you ask whether certain radial passenger car tires may be imported if they are tested to see that they meet DOT requirements (Federal Motor Vehicle Safety Standard No. 109; 49 CFR @ CFR 571.109), and if the information required pursuant to paragraph S4.3 of Standard No. 109, which does not presently appear on the tires, is branded with a hot stamp on the tire sidewalls.

The NHTSA does not view with approval the importation into the United States of passenger car tires that were not originally designed and manufactured for importation into the United States. Although Standard No. 109 as presently written does not prohibit the branding of information required by the standard onto the tire, as long as the information becomes part of the actual sidewall material, it is difficult for us to understand how a manufacturer can, in branding the necessary information, readily assume that the information is in fact reflective of the tire's performance capability. To stipulate as you do that the tires will be tested to Standard No. 109 is not responsive to the issue, for in the case of the Standard No. 109 tests, which are destructive in nature, only sample testing is conducted, and the tires actually imported are not themselves tested. Consequently, the testing of tires by a manufacturer that he desires to brand and import into the United States will only provide reliable evidence of conformity if the manufacturer's testing is of uniform batches or lots.

A similar problem is presented by a manufacturer's branding onto the tire of the identification number required by Part 574. This number is required to be based on certain facts regarding the manufacture of the tire; the week and year of manufacture. Consequently, this information must be known to the manufacturer if his identification number is to be consistent with Part 574.

In summary, the NHTSA's position regarding the branding and subsequent importation of tires not originally manufactured for importation into the United States is that although the practice is not prohibited by the National Traffic and Motor Vehicle Safety Act, Standard No. 109, or the regulations regarding the importation of motor vehicle equipment (19 CFR 12.80), manufacturers who brand tires must base their representations of conformity to the standard and to the identification requirements on information which, in the exercise of due care, they know to be accurate. Because such conformity is not apparent from an examination of these tires or even from post-production testing you should be aware that the NHTSA may request documentation that supports any manufacturer's representations regarding conformity.

Sincerely,

Secretary of Transportation National Highway Safety Bureau US Department of Transportation May 9, 1973

Part 571 - Federal Motor Vehicle Safety Standards

We manufacture among others, person radial tires. Today they have not all letters and numerals, required by motor Vehicle Safety Standard No. 109, S4.3 "Labeling requirements".

Question: Is it possible for us to export these tires to U.S.A. if we

- test them and find that they meet the DOT-qualifications

- brand the required text with a hot stamp on the sidewalls of the cured tires. Reason: The letters and numerals are not molded into the sidewalls.

Tire Research

Erik (Illegible Word)

NATIONAL HIGHWAY TRAFFIC SAFETY ADMIN US DEPT OF TRANSPORTATION

ATTENTION LAWRENCE R SCHNEIDER CHIEF CONSUL WE REFER TO OUR LETTER DATED [Illegible Words] 1973 AND ASK YOU PLEASE TO GIVE US AN ANSWER THANKS IN ADVANCE STOP

ERIK SUNDELIN [Illegible Words] JUL 4 1973 1050

ID: nht73-2.32

Open

DATE: 11/06/73

FROM: AUTHOR UNAVAILABLE; W. R. Fiste; NHTSA

TO: The Bendix Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This replies to your letter of October 17, 1973.

We have studied the comments contained in your letter carefully, and based on your extensive experience, have no reason to believe that your use of tubing made of solid neoprene rubber for the application in question constitutes a safety hazard.

Since there is limited movement involved, the use of "tubing" rather than "hose" is appropriate. The Bureau has not, as yet, established standards other than the general requirements of paragraph 393.43(a) for brake tubing used in applications which do not flex. Use of coiled nylon brake tubing for connections between towed and towing vehicles is permitted if the tubing meets the requirements for Type 3B nylon tubing set forth in SAE Standard J844.c.

We appreciate your interest in this safety matter and trust the above is responsive to your inquiry.

ID: nht73-2.33

Open

DATE: 04/10/73

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Independent Tire Dealer

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your letter of September 26, 1968, to Mr. Robert M. O'Mahoney, Assistant Chief Counsel, concerning clearance lamp mounting on bodies installed on chassis-cabs.

It is required by Federal Motor Vehicle Safety Standard No. 108 that clearance lamps be mounted as near as practicable to the upper left and right extreme edges of the vehicle. The cab mounted clearance lamps shown on your drawing CA1030-40, dated September 24, 1968, being mounted approximately 16 inches inboard of the extreme body width, do not appear to be as near as practicable to the extreme edges of the vehicle. Lamps mounted at the right and left extreme edges of the widest part of the body panel would meet the requirements. The mounting height of these lamps should be as high as practicable without causing objectionable glare in the rear view mirror. Retention of cab mounted clearance lamps is optional.

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

ID: nht73-2.34

Open

DATE: 11/07/73

FROM: R.B. DYSON -- ASST. CHIEF COUNSEL, NHTSA; SIGNATURE BY JOHN G. WOMACK

TO: Missouri Automobile Dealers Assoc.

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of October 10, 1973, concerning the legality of disconnecting seat belt interlocks.

The interlock is a required item of safety equipment that must be operable on any new car when it is sold or offered for sale, pursuant to section 108(a)(1) of the National Traffic and Motor Vehicle Safety Act. After an interlock equipped car is sold, however, the purchaser may disconnect the interlock, without violating the Act, by virtue of section 108(b)(1), which exempts transactions after the first purchase of the vehicle.

If a dealer offers to disconnect an interlock as an inducement to the sale of the vehicle, it is our opinion that a violation of the act occurs even though the actual disconnection may take place after delivery of the vehicle. If, on the other hand, the subject of the interlock is not discussed during the sale and the buyer subsequently requests disconnection on the basis of his experience with the vehicle, the dealer would not violate the Act if he disconnected the interlock.

Although a dealer does not violate the act by suggesting that the buyer go somewhere else to have the interlock disconnected, I am sure you appreciate the troublesome consequences such advice may bring for the buyer if the resulting disconnection is carelessly performed.

YOURS TRULY,

October 10, 1973

Dr. James B. Gregory, Administrator National Highway Traffic Safety Administration

Dear Dr. Gregory:

As you can see from the enclosed article of the October 1, 1973 issue of Automotive News, it is reported by Congressman Dante B. Fascell, that he received a letter August 20, 1973 from Robert L. Carter, Associate Administrator of Motor Vehicle Programs, in which he states:

"Once an individual has purchased and taken delivery of the vehicle, intending to use it and not simply to resell it, it passes beyond the scope of the standards (safety belt interlocks). The owner could thereupon modify it, or have the dealer modify it, without threat of sanction under the act."

Dr. Gregory, many of my dealers have called wanting to know if the report by Mr. Carter is the truth. Can you tell me?

1. Is it a violation for my dealers after they make the sale to disconnect the interlock system or make it inoperative?

2. Is it against the law for a dealer to tell a purchaser of a 1974 car that he can go some where else and get it disconnected?

Please advise at your earliest convenience.

Sincerely,

MISSOURI AUTOMOBILE DEALERS ASSOCIATION

Ralph J. Kalberlon Executive Vice President Joe Machens President

cc: David Castles, Castles-Wilson Buick Casey Meyers-Casey Meyers Ford, Inc.

in the letterbox

Who can tamper?

On Page 1, of the Sept. 10 issue of AUTOMOTIVE NEWS, appears a story by J. Donald Williamson, "First Buyers Turned Off by Interlocks."

The second and third paragraphs of your story read as follows:

"Forbidden by law to remove or tamper with the new system, dealers resorted to their own ingenuity to allay customer gripes and many and varied were the suggestions.

"Generally, stringent objections were met by suggesting the customer might stop at a service station on the way home where mechanics not hampered by federal edict could render the system inoperative."

After studiously searching for an answer to this question we finally received a letter dated Aug. 22, from Congressman Dante B. Fascell in which he enclosed a letter dated Aug. 20, 1973, he received from Robert L. Carter, Associate Administrator of Motor Vehicle Programs. The third paragraph reads as follows:

"In the case of starter interlock safety belts, they are required, at the time of purchase, in all passenger cars manufactured on or after Aug. 15, 1973. Once an individual has purchased and taken delivery of the vehicle, intending to use it and not simply to resell it, it passes beyond the scope of the standards. The owner could thereupon modify it, or have the dealer modify it, without threat of sanction under the act."

It appears that the ruling from the U.S. Department of Transportation is directly contrary to the information conveyed in your story.

This matter is of such importance to all dealers we think it imperative that you retract our statement.

If by chance there is a subsequent ruling from the administrator, then we would be grateful if you would immediately furnish us with the latest release -- Edgar Jones, general manager, Nolan - Brown Motors, Inc., Miami.

Motors safety experts (AMC models were the only ones involved in the story).

As is pointed out in Reader Jones' letter, the law appears to permit a dealer to modify the interlock after the car is sold.

Dealers should keep in mind, however, that it is clearly the intent of the law that nobody tamper with the interlock. AMC people are obviously taking a supercautious stance.

Furthermore, a House bill currently under consideration would ban anyone, including the owner, from tampering with any safety item.

ID: nht73-2.35

Open

DATE: 10/05/73

FROM: ROBERT L. CARTER -- ASSOC. ADM., MVP, NHTSA; SIGNATURE BY ELWOOD T. DRIVER

TO: State Motor Vehicle Administration

TITLE: FMVSR INTERPRETATION

TEXT: I have checked the sample ANSID-19.4 title and odometer disclosure forms which were submitted by you and Mr. Pfaff for review.

The odometer disclosure form complies with the disclosure regulation, 49 CFR Part 580. The odometer disclosure portion of the title document complies except for a blank for Last Plate Number and a reference to the Motor Vehicle Information and Cost Savings Act which points out the civil liabilities for failure to comply.

If we can be of any more assistance, please contact our office.

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.