Skip to main content

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 13191 - 13200 of 16490
Interpretations Date

ID: nht76-4.8

Open

DATE: 09/22/76

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Imperial Chemical Industries Limited

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your July 2, 1976, question whether evaluation of the lubricity of DOT 4 brake fluid by the Society of Automotive Engineers (SAE) modified stroking test (SAE J1703f) is consistent with the requirements of Standard No. 116, Brake Fluids.

Standard No. 116 specifies that the stroking properties of DOT 4 brake fluids be tested by use of the apparatus described in SAE Standard J1703b. This is the procedure that would be used in a determination of whether a certain brake fluid conforms to the requirements of Standard No. 116. Section 571.5 of our regulations (49 CFR Part 571) provides that materials subject to change are incorporated into a standard as provided in the standard or, if no indication is made, as of the date of adoption of Part 571. In this case, the standard indicates that J1303b is the version of the SAE practice that has been incorporated.

This does not mean that you cannot use the modified SAE procedure for purposes of your certification testing. Your obligation as a manufacturer is to ensure that your certification of compliance is not false or misleading in a material respect, and that you have exercised due care in manufacturing to conform to Standard No. 116 (15 U.S.C. @ 1397(b) (2)). A manufacturer is not required to follow specifically the test procedures of the standards. Rather, he must ascertain, in the exercise of due care, that his product will conform to the requirements of the standard when it is tested by the stated methods. The NHTSA cannot approve a manufacturer's test procedure as the basis of due care in advance of the actual events that underlie certification.

Sincerely,

ATTACH.

Imperial Chemical Industries Limited

Petrochemicals Division Headquarters

National Highway Traffic Safety Administration -- Department of Transportation

JULY 2, 1976

Dear Sirs

DOT 4 BRAKE FLUID

We refer to your specification for DOT 4 grade brake fluid as given in the Federal Motor Vehicle Safety Standard No 116, published in the Federal Register, Vol 36, No 122, June 24 1971.

We note that in section S6.13 the evaluation of stroking properties follows the procedure given in SAE J 1703b section 4.12 "Simulated Service Performance".

However our latest SAE Standard for brake fluid (SAE J1703f) contains details of a modified stroking test.

We are considering changing our stroking test apparatus to comply with SAEJ1703f and would be grateful if you could confirm that evaluation of brake fluid lubricity by this method is acceptable for DOT 4 grade fluid.

Yours faithfully

J J Cowley

ID: 3005yy

Open

Mr. John E. Calow
Sr. Safety Engineer
Oshkosh Truck Corporation
Chassis Division
P. O. Box 2508
2201 Oregon St.
Oshkosh, Wisconsin 54903-2508

Dear Mr. Calow:

This responds to your letter concerning the responsibilities of an incomplete vehicle manufacturer under Federal Motor Vehicle Safety Standard No. 115, Vehicle Identification Number--Basic Requirements. In your letter, you explained that Oshkosh provides chassis to final stage manufacturers. You stated that the final stage manufacturers are requesting that Oshkosh provide a duplicate VIN tag with the incomplete vehicle. The additional VIN tag would be affixed by the final stage maufacturer, so that it is readable through the vehicle glazing. You noted that there is a possibility that the final stage manufacturer might place the incorrect VIN tag under the vehicle glazing, and that Oshkosh would have no control of the final stage manufacturer correctly identifying the vehicle. You then asked two questions, which are addressed below.

Your first question asked whether it is legal for an incomplete vehicle manufacturer to supply the final stage manufacturer with an additional "loose" VIN tag. The answer to this question is yes. No provision in Standard No. 115 prohibits the incomplete vehicle manufacturer from providing an extra VIN tag which the final stage manufacturer may affix so that it is visible through the vehicle glazing.

Your second question asked about the legal responsibilities of the incomplete vehicle manufacturer if an incorrect VIN tag is affixed to the vehicle by the final stage manufacturer. Except in the situation where an incomplete vehicle manufacturer assumes legal responsibility for all duties and liabilities imposed on manufacturers by the Safety Act (see 49 CFR Part 568.7), which we assume does not apply in your case, an incomplete vehicle manufacturer is not responsible under the Safety Act for the actions of a final stage manufacturer.

I hope this satisfactorily responds to your concerns. If there are any further questions, please write to me or contact Dorothy Nakama of my staff at (202) 366-2992.

Sincerely,

Paul Jackson Rice Chief Counsel

/ref:115#567#568 d:5/20/9l

2009

ID: nht91-4.2

Open

DATE: May 20, 1991

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: John E. Calow -- Sr. Safety Engineer, Oshkosh Truck Corporation, Chassis Division

TITLE: None

ATTACHMT: Attached to letter dated 3-8-91 from John E. Calow to Dorothy Nacoma (OCC 5889)

TEXT:

This responds to your letter concerning the responsibilities of an incomplete vehicle manufacturer under Federal Motor Vehicle Safety Standard No. 115, Vehicle Identification Number--Basic Requirements. In your letter, you explained that Oshkosh provides chassis to final stage manufacturers. You stated that the final stage manufacturers are requesting that Oshkosh provide a duplicate VIN tag with the incomplete vehicle. The additional VIN tag would be affixed by the final stage maufacturer, so that it is readable through the vehicle glazing. You noted that there is a possibility that the final stage manufacturer might place the incorrect VIN tag under the vehicle glazing, and that Oshkosh would have no control of the final stage manufacturer correctly identifying the vehicle. You then asked two questions, which are addressed below.

Your first question asked whether it is legal for an incomplete vehicle manufacturer to supply the final stage manufacturer with an additional "loose" VIN tag. The answer to this question is yes. No provision in Standard No. 115 prohibits the incomplete vehicle manufacturer from providing an extra VIN tag which the final stage manufacturer may affix so that it is visible through the vehicle glazing.

Your second question asked about the legal responsibilities of the incomplete vehicle manufacturer if an incorrect VIN tag is affixed to the vehicle by the final stage manufacturer. Except in the situation where an incomplete vehicle manufacturer assumes legal responsibility for all duties and liabilities imposed on manufacturers by the Safety Act (see 49 CFR Part 568.7), which we assume does not apply in your case, an incomplete vehicle manufacturer is not responsible under the Safety Act for the actions of a final stage manufacturer.

I hope this satisfactorily responds to your concerns. If there are any further questions, please write to me or contact Dorothy Nakama of my staff at (202) 366-2992.

ID: nht88-4.1

Open

TYPE: INTERPRETATION-NHTSA

DATE: 11/03/88

FROM: ERIKA Z. JONES -- NHTSA CHIEF COUNSEL

TO: BRIAN HALL -- PRESIDENT, VS TECHNOLOGY

TITLE: NONE

ATTACHMT: LETTER UNDATED FROM BRIAN HALL TO VINSON, OCC 2576

TEXT: Dear Mr. Hall:

This is in reply to your recent undated letter to Mr. Vinson of this Office. You have described a safety apparatus and have requested "approval" from the Department. The apparatus is a red light that is worn on the back of a rider on small open vehicles such as motorcycles. The light connects to the stop lamp system on the vehicle and is activated at the same time as the vehicle's stop lamp.

The Department has no authority to "approve" or "disapprove" specific concepts or equipment. However, it can advise whether such is permissible or impermissible under Federal statutes or Departmental regulations. Yours is a unique device, and there are no Federal motor vehicle safety standards that apply to it. Our primary concern is whether its operation would in any way interfere with the effectiveness of the vehicle's stop lamp, such as a power drain that would make that light less bright. Becaus e the apparatus is "apparel not a system part...which is intended for use exclusively to safeguard motor vehicles, drivers, passengers...from risk of accident, injury, or death", it meets the statutory definition of "motor vehicle equipment." This means that the apparatus is subject to Federal notification and remedy provisions in the event a determination is made that it incorporates a defect that relates to motor vehicle safety.

Because the Department has no authority to regulate how a vehicle is used on the public roads, you may wish to investigate whether the apparatus is acceptable under the laws of the individual States. The American

Association of Motor Vehicle Administrators may be able to provide you with an answer. Its address is 4600 Wilson Boulevard, Arlington, Va. 22203.

We appreciate your interest in improving safety.

Sincerely,

ID: nht95-7.21

Open

TYPE: INTERPRETATION-NHTSA

DATE: October 13, 1995

FROM: Samuel J. Dubbin -- Chief Counsel, NHTSA

TO: Borje Kukka

TITLE: NONE

ATTACHMT: Attached to 10/11/95 letter from Gerald R. Stewart to NHTSA Office of Chief Counsel (OCC 11281)

TEXT: Dear Mr. Kukka:

This response to your request for an interpretation whether NHTSA's statutes and regulations would apply to a process you intend to market, in which two horizontal parallel grooves are etched into the lower portion of motor vehicle windshields. The groves apparently facilitate windshield cleaning by scraping water and debris off the windshield wipers as the wipers pass over the grooves. You provided a videotape on the process and a portion of a windshield etched with the grooves.

I am enclosing two interpretation letters, one dated March 1, 1985 and another dated October 28, 1988, both addressed to Mr. Andrew P. Kallman of Lansing, Michigan. Mr. Kallman asked NHTSA's opinion of a process that is very similar to your process. The letters explain how NHTSA's regulations would apply if your process were used on new vehicles or windshields and on windshields of a used vehicle.

Please also note, NHTSA has no authority to "approve" or certify your process. If you understood any previous correspondence from agency personnel to mean that NHTSA approves of your product, has endorsed it an any manner, or has made commendations about it (e.g., it "can improve a driver's ability to drive safely,") that is incorrect, and we apologize for any confusion.

State laws may affect operations that you conduct in that State. If you decide to do business in a particular State, you should seek legal advice on requirements for conducting your type of business in that State, including requirements the State may have for persons modifying windshields or for vehicles with modified windshields.

I hope the enclosed information is helpful to you. Should you have any questions concerning NHTSA's legal authority, please write to me at this address or contact Dorothy Nakama of my staff at (202) 366-2992. Our FAX number is (202) 366-3820. I am, under separate cover, returning your videotape and windshield portion.

ID: 24322.ztv

Open

Mr. Jesus Cid
3139 Minonee Lane
Carson, NV 89701

Dear Mr. Cid:

Senator Reid has asked us to reply to your e-mail to him requesting information on the legality of neon lights "on the outside or inside" of your car.

I am enclosing copies of representative letters we have sent some other persons who asked this question. These are our letters of April 21, 1992, to Allan Schwartz of Tron Industries, and of July 29, 1993, to Charles D. Shipley, Director, Ohio Department of Public Safety. The views expressed in these letters remain unchanged today, in 2002 (however, the American Association of Motor Vehicle Administrators (AAMVA) no longer provides interpretations of State laws).

You did not specify the location on the outside of the car where you would like to install neon lights. The most frequent location appears to be under the car, and the letters we are sending you address underbody neon lighting. However, these letters do not cover neon lighting in the interior (see discussion below).

Federal law permits you as a vehicle owner to modify your vehicle personally in any way you wish. However, these modifications are subject to State law. We are not conversant with State laws, and, specifically, we do not know whether neon lighting on or in a motor vehicle is permitted by Nevada. We suggest that you call your local office of the Department of Motor Vehicles.

If the neon lighting is to be installed by a person other than yourself (specifically, a manufacturer, distributor, dealer, or motor vehicle repair business), there is an applicable provision of Federal law. This law is intended to ensure that the performance of original equipment installed as required by a Federal motor vehicle safety standard is not diminished by modifications after the vehicle is first sold. To avoid violating this law, the installer of the neon lighting should determine that its use would not have a negative effect upon the performance of the vehicle's original lighting equipment which has been installed, as required, by a Federal motor vehicle safety standard (or any other equipment installed in accordance with such a standard). For example (see our letter to Mr. Schwartz), the intensity of neon lights on the exterior should not mask the intensity of turn signal and stop lamps. A neon light in the interior should not be placed in the rear parcel shelf to avoid confusion and diminishing the effect of the center highmounted stop lamp. Even if you and the installer decide that the neon lighting you desire would not have a negative effect upon the performance of other lamps, the legality of neon lighting remains subject to the laws of Nevada, or any other State where the car is driven.

Sincerely,
Jacqueline Glassman
Chief Counsel
Enclosures
ref:108
d.5/17/02

2002

ID: nht87-3.42

Open

TYPE: INTERPRETATION-NHTSA

DATE: 12/10/87

FROM: AUTHOR UNAVAILABLE; Erika Z. Jones; NHTSA

TO: Interworld Commodities, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: Mr. Isaiah Herman President Interworld Commodities, Inc. 15 West 44th Street New York, NY 10036

Dear Mr. Herman: This is in reply to your letter of October 13, 1987. One of your clients "plans to purchase a Corporation Stretched Limousine" to be shipped to Japan, and would like "to obtain the standards and regulations for the modifications that are done to the vehi cle". The car in question is a Lincoln Town Car.

We understand that the Lincoln Town Car is available from several converters in a lengthened, or "stretched" version. We further understand from a conversation that you had with Taylor Vinson of this Office that your clients intend to purchase the vehicl e and have it converted after title passes to them. The converter is subject to the restriction that it must not render inoperative in whole or in part any device or element of design installed in accordance with a Federal motor vehicle safety standard. This restriction applies regardless of the future use or location of the vehicle. However, the Federal motor vehicle safety standards do not apply to new and untitled vehicles that a manufacturer intends for export, and if the alterations to a car owned by your clients resulted in noncompliances we would regard this as only a technical violation of the restriction provided that the vehicle were shipped to japan immediately following the modifications.

I hope that this answers your questions. Forgive our delay in replying to you.

Sincerely,

Erika Z. Jones Chief Counsel

10/13/87

Ms. Erika Jones Office of the Chief Council NHTSA Room 5219 400 7th Street S.W. Washington D.C. 20590

Dear Ms. Jones,

I was told today via one of your staff that you can be of assistance. I have a client who, has plans to purchase a Corporation Stretched Limousine to be shipped to Japan.

They would like to obtain the standards and regulations for the modifications that are done to the vehicle. If there are none please be kind enough to send a letter stating that fact.

I further understand Code of federal Regulations Volume 49 CRF 500 Series would be helpful. Please indicate where to obtain the regulations and any other standards. They are considering purchasing a Lincoln Town Car.

Thank you

Sincerely,

Isaiah Herman

President

ID: nht81-3.3

Open

DATE: 07/31/81

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: C. J. B. Industries, Inc.

TITLE: FMVSS INTERPRETATION

TEXT:

NOA-30

Mr. Carol Fitzjohn Quality Control Manager C.J.B. Industries, Inc. P. O. Box 779 Chanute, Kansas 66720

Dear Mr. Fitzjohn:

This responds to your June 2, 1981, letter asking about the requirements for reservoir tanks for air brake systems. In particular, you ask whether section S5.1.2.2 and S5.2.1.3 are the only Federal requirements applicable to the manufacture of the reservoirs.

The two sections that you referenced in your letter are the only sections specifying requirements for the construction of reservoirs for air brake systems. For additional guidance in the construction of reservoirs, you should refer to SAE Standard J10b titled "Automotive and Off Highway Air Brake Reservoir Performance and Identification Requirements." This standard will provide you with the prevailing industry practice in the construction of reservoirs.

You should be aware that you would be responsible under the National Traffic and Motor Vehicle Safety Act if there were any defect relating to motor vehicle safety in your product.

Sincerely,

Frank Berndt Chief Counsel

June 2, 1981

NHTSA Office of Chief Counsel, NOA-30 400 Seventh St. Southwest Washington, D. C. 20590

Gentlemen:

As a manufacturer of pressurized containers, we from time to time are asked to design and or manufacture components for over the road vehicles; and as such have been approached recently by a prospective customer to manufacture a reservoir under the provisions of the "Motor Vehicle Safety Standard No. 121." However, this is where the problem arises. The standard as written does not specify in detail the construction of the reservoir, with respect to materials to be used or the wall thickness of the tank, or list a reference to any other document to which this information is found.

It is imparative for us to manufacture components in the least expensive way and still maintiin a high degree of quality. Therefore, to exceed provisions of a standard only enhances the construction costs.

We would appreciate an opinion on the clarity of sections S5.1.2 through S5.2.1.5 as to whether the construction of said reservoir meet only the provisions of sections S5.1.2.2 and S5.2.1.3; or are there additional requirements not contained therein.

We appreciate any consideration to this matter you can give us in a short amount of time.

Respectfully,

Carol Fitzjohn Quality Control Manager C.J.B. Industries, Inc.

CDF/pac

ID: 12158.wpd

Open

Mr. Gilbert Lenkiewicz
c/o Mr. Haydn Doughty
Cybernet Services Incorp.
704 Edgewater Drive
Dayton, TN 37321

Dear Mr. Lenkiewicz:

This is in response to your letter of June 23, 1996, to John Womack of this Office. We are sending it to you in care of Haydn Doughty as your letter has no return address on it, and the envelope in which it came has been misplaced.

We appreciate your including copies of your letter of March 14, 1996, and Mr. Womack's response of April 4 to Cybernet Services Incorp. In the system you described, an aftermarket strobe light is installed in the center highmounted stop lamp assembly to flash before the activation of the stop lamp signal. Mr. Womack informed Cybernet that this is not permissible under Federal law unless the strobe light is installed by the vehicle owner. This is because Federal Motor Vehicle Safety Standard No. 108 requires all stop lamps to be steady burning when the brake pedal is applied.

You inform us in your letter of June 23 that you have revised the design which "still requires the addition of a strobe light . . . but now does not delay the operation of the normal 'Third Stop Light', during the 3-second flash time of the strobe light." To explain, there will be

"a 3 Watt strobe 'flash' approximately 3-4 times for a period of 3 seconds, anytime the brakes are initially applied. This cycle will only repeat when the brake pedal is released and again depressed. The rapid flashing occurs concurrently with the energization of the normal 'Third Stop Light.' At no time are any of the original stop lamps precluded from providing their intended 'steady burning' indication of both the car and driver's action, i.e. stopping."

I am sorry to inform you that this modification does not alter our previous advice to you. The

fact that the center stop lamp filament is activated simultaneously with the strobe light, rather than after it, does not change the fact that the center stop lamp will be perceived as flashing, even if the stop lamp bulb is steady burning.

If you have further questions, you may refer them to Taylor Vinson of this Office 9202-366-5263).

Sincerely,

Samuel J. Dubbin
Chief Counsel

ref:108
d:7/23/96

1996

ID: nht75-5.26

Open

DATE: 09/18/75

FROM: AUTHOR UNAVAILABLE; Frank A. Berndt; NHTSA

TO: Toyota Motor Sales U.S.A. Inc.

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your letter of July 30, 1975, in which you asked whether the uniform tire quality grading requirements for furnishing information to prospective purchasers of vehicles apply to prospective purchasers of vehicles other than passenger cars that may be equipped with passenger car tires. This was asked in light of the fact that the tire quality grading rule itself applies to tires manufactured for use on passenger cars

We do not consider that the requirements of @ 575.6(a) and (c), regarding the furnishing of consumer information to motor vehicle buyers and prospective purchasers, apply to the sale of trucks or other non-passenger-car vehicles where uniform tire quality grading information is concerned.

We recognize that the language of the regulation may not be entirely clear in this regard, and are considering an interpretive amendment to clarify it.

Sincerely,

July 30, 1975

James B. Gregory -- Administrator, National Highway Traffic Safety Administration, U. S. Department of Transportation

Re: Interpretation of Section (d)(1)(ii) of @ 575.104, Uniform Tire Quality Grading Standards

Dear Dr. Gregory:

We are somewhat confused by certain of the requirements of @ 575.104, Uniform Tire Quality Grading Standards, and would appreciate your clarification of them for us.

@ 575.104 (d)(1)(ii) specifies:

"In the case of information required in accordance with @ 575.6(c) to be furnished to prospective purchasers of motor vehicles and tires, each vehicle manufacturer and each tire manufacturer or brand name owner shall as part of that information list all possible grades for traction and temperature resistance, and restate verbatim the explanations for each performance area specified in Figure 2. . . ."

@ 575.104(c), Application, states that this section applies to new pneumatic tires for use on passenger cars after 1948.

Our question, therefore, is whether or not the requirements of @ 575.104(d)(1)(ii) apply to manufacturers of trucks for which passenger car tires are used.

Since this is an urgent matter, we would appreciate your response as soon as possible. Thank you.

Very truly yours,

TOYOTA MOTOR SALES, U.S.A., INC. -- Y. UEDA FOR

K. Nakajima -- Director/General Manager, Factory Representative 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.

Go to top of page