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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 13121 - 13130 of 16490
Interpretations Date

ID: 1982-3.2

Open

TYPE: INTERPRETATION-NHTSA

DATE: 08/20/82

FROM: FRANK BERNDT -- CHIEF COUNSEL, NHTSA; SIGNATURE BY STEPHEN P. WOOD

TO: Zimmer Corporation

TITLE: FMVSR INTERPRETATION

TEXT: Thank you for your letter of August 6, 1982, to the Administrator asking whether there is "any blanket waiver of standards solely based on a small production of vehicles."

You are correct that no such waiver exists. Even a single automobile manufactured for use on the public roads must meet all applicable Federal motor vehicle safety standards unless exempted by the Administrator under the provisions of Part 555. A manufacturer whose total motor vehicle production in the year preceding filing of his petition does not exceed 10,000 units is eligible to apply for an exemption of up to three years on a hardship basis. Any manufacturer of motor vehicles may apply for an exemption of up to two years on the three remaining bases that you mention but the exemption extends only to a maximum of 2500 vehicles in any 12-month period that the exemption is in effect.

Under the original exemption authority, in effect from 1968 to 1971, exemptions were available on a hardship basis and the threshold of eligibility was 500 units.

SINCERELY,

ZIMMER CORPORATION

August 6, 1982

Administrator, National Highway Traffic Safety Administration

Gentlemen:

From time to time I am confronted with statements to the effect that if a vehicle manufacturer produces not more than "X" quantity of vehicles, such vehicles are not required to be in compliance with the FMVSS. The quantity of vehicles referenced varies from 250 to 2000 depending on the source of the statement.

I am aware of the provisions of Part 555 covering temporary exemption from the standards under special conditions of economic hardship, development of new vehicle safety and low-emission engine features, and equivalent vehicle safety. But I am not aware of any blanket waiver of standards solely based on a small production of vehicles.

Please advise.

R. H. Zelinske Vice President Corporate Engineering

ID: nht91-6.21

Open

DATE: October 14, 1991

FROM: Robert W. Smith -- President, Auto Safety Corporation

TO: Taylor Vinson -- Senior Staff Attorney, NHTSA

TITLE: None

ATTACHMT: Attached to letter dated November, 1991 (est) from Paul Jackson Rice to Robert W. Smith (A38; Std. 108)

TEXT:

My partner and I want to thank you for all the help you gave us during the course of the meeting in your office on August 15, 1990.

Since that meeting we have been continuing the development of our prototype stop lamp license plate frame, in order to conform to all applicable NHTSA standards.

The purpose of this letter is to confirm what we learned at that meeting. Your computer search of Safety Standard #108 data as it would apply to our device, the flashing/steady burning stop lamp, turned up the following:

1. In the case of the Simcox letter (A29, Redbook 3, Erika Z. Jones to Bettie Lou Simcox, October 24, 1986), the use of a flashing/steady burning stop lamp is permissible on a motorcycle. As you'll recall, our embodiment, which complies with specifics of the Safety Standard #108, is a specially designed license plate frame that incorporates a light assembly and a patented (U.S. Patent No. 4,871,945) electronic circuit. (See attached drawings Fig. 1 and Fig. 2)

2. Safety Standard #108 also would allow the use of a flashing/steady burning stop lamp on passenger cars. Specifically, for our purposes, in the embodiment of a license plate frame with built-in lights and circuitry. (Drawing Fig. 1)

3. Safety Standard #108 would permit the use of an auxiliary flashing/steady burning stop lamp which could be mounted on the rear of vans, pickup trucks, and mini vans. (Drawing Fig. 3)

In closing, we again thank you for the help you have given us.

ATTACHMENT

Motor vehicle flashing/steady burning stop lamp license plate frame. (Fig. 1 and Fig. 2) (Graphics omitted)

Auxiliary flashing/steady burning stop lamp. (Fig. 3) (Graphics omitted)

ID: nht81-3.27

Open

DATE: 10/15/81

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: Colt Industries, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your recent letter asking whether any Federal regulations apply to propane fuel systems designed for use in motor vehicles.

I am enclosing an information sheet which sets forth the implications under federal law of converting gasoline-powered vehicles to use propane or other types of gas, as well as a general discussion of auxiliary fuel tanks. From that discussion, you will see that there are no safety standards directly applicable to propane fuel systems on motor vehicles, if propane is the only fuel involved. There are, however, specifications under the Bureau of Motor Carrier Safety regulations relating to propane fuel systems on commercial vehicles or to tanks used for shipment of propane gas in interstate commerce. If your tanks will be used on vehicles other than private vehicles, these regulations may be of interest to you. For further information, you may contact Mr. W. R. Piste of the Bureau of Motor Carrier Safety (202-426-0033).

ENC.

Colt Industries Inc

August 17, 1981

Frank Bernt Chief Counsel National Highway Traffic Safety Administration

Dear Mr. Bernt:

A division of Colt Industries is interested in developing and marketing a liquified propane gas fuel system for motor vehicles.

It is naturally of vital importance that we be familiar with any federal design, performance or private laboratory (United Laboratories) approval regulations that might exist. On this matter, our contact with NHTSA officials has uncovered no such regulations. Your comments would be most appreciated.

Thank you for your assistance in this matter. Please don't hesitate to contact me if you should have any questions.

SINCERELY,

DON W. UPSON

cc: W. POTOROKA

ID: nht90-3.35

Open

TYPE: Interpretation-NHTSA

DATE: July 30, 1990

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

TO: J.P. Ravier -- R & D Director, Valeo Lighting Company

TITLE: None

ATTACHMT: Attached to letter dated 12-13-90 to M.J.P. Ravier from Paul Jackson Rice (A36; Std. 108); Also attached to letter dated 7-13-90 to P.J. Rice from J.P. Ravier and Guy Dorleans (OCC 5304)

TEXT:

This is in answer to your letter to Mr. Rice dated July 13, 1990, in which you solicit a response from the agency concerning the acceptability of your headlamp aiming device under existing Federal Motor Vehicle Safety Standards and claim confidentiality for certain drawings submitted with your letter. Your request for an interpretation will be handled in separate correspondence.

When confidential protection is claimed for material submitted to the National Highway Traffic Safety Administration (NHTSA), our confidential regulation, 49 C.F.R. S512, requires the submission of a certification stating that the submitter has made dili gent inquiry to ascertain that the information submitted has not been disclosed, or otherwise made public (49 C.F.R. S512.4(e)) and other supporting information. In the absence of such a certification, I am deprived of proper and sufficient justificatio n by which to review your request to protect any of this information from public disclosure.

Although you have not submitted this certification, I will waive the requirement for the limited purpose of expediting the review process. I have examined the two drawings you have submitted and decided that they should be treated confidentially because their release to the public could cause substantial competitive harm to your company. I will protect these drawings for an indefinite period of time. Compliance with our confidentiality regulation will be expected for all future submissions of informa tion claimed to be confidential.

Please inform NHTSA of any changed circumstances which may affect the protection of the information (49 C.F.R. S512.4(i)).

ID: nht88-3.89

Open

TYPE: INTERPRETATION-NHTSA

DATE: 11/03/88 EST

FROM: ERIKA Z. JONES -- CHIEF COUNSEL, NHTSA

TO: BRIAN HALL -- PRESIDENT, VS TECHNOLOGY

ATTACHMT: MEMO TO MR. VINSON - VS TECHNOLOGY; FROM BRIAN HALL, OCC-2576

TEXT: 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." Thi s 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.

ID: 3149o

Open

Mr. Brian Hall
President, VS Technology
3046 E. Dover St.
Mesa, AZ 85213

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. Because 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,

Erika Z. Jones Chief Counsel

/ref:108 d:ll/3/88

1970

ID: nht93-8.20

Open

DATE: November 16, 1993

FROM: Jim Davis -- President, Russell Performance Products

TO: David Elias -- DOT

COPYEE: Bill Collins -- Titeflex

TITLE: None

ATTACHMT: Attached to letter dated 5/12/94 from John Womack to Jim Davis (A42; Std. 106), letter dated 10/22/93 from Jim Davis to David Elias (OCC-9249), and letter dated 10/22/93 from Jim Davis to NHTSA Office of Vehicle Safety Standards, Crash Avoidance Division

TEXT:

After our recent phone conversation I re-read my copy of NHTSA's 49 CFR Ch. V (10-1-88 Edition) covering the marking of brake hose assemblies. Unless I am reading this incorrectly, it seems that we do not need marking on the hose once it has been made into an assembly.

S5.2.2 says that "Each hydraulic brake hose shell be labelled or cut from bulk brake hose that is labelled, etc." But then it goes on to say that "The formation need not be present on hose once it has become part of a brake hose assembly or after it is installed in a motor vehicle." It would seem to me that the phrase "once it has become a part of a brake hose assembly" would relieve us of the necessity to mark the hose.

The copy that I am reading this from is a very indistinct Xerox that I may be misinterpreting.

I can understand the need for interim marking if the hose is placed in commerce in an unassembled state. But that is not the case here where we are the ONLY customer with Titeflex for this particular hose and we make it into assemblies which otherwise meet all the specifications required by NHTSA.

I will call you in a few days to discuss this with you.

ID: nht67-1.24

Open

DATE: 08/18/67

FROM: AUTHOR UNAVAILABLE; Lowell K. Bridwell; NHTSA

TO: Mercedes-Benz of North America, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your request to Dr. Haddon for an interpretation of the term "rigid material" as it appears in paragraph S3.4.1(b) in the National Highway Safety Bureau's "talking paper" of July 6, 1967. This term is identical to that used in paragraph S.3.4.1(b) of Standard 201, issued August 11, 1967. Therefore, the following interpretation applies to Standard 201 as issued August 11, 1967, a copy of which is enclosed.

"Rigid material" does not include a supporting structure of an armrest that is made of flexible spring steel if the supporting structure is designed to flex in the direction of transverse impact upon the pelvic impact area.

MERCEDES-BENZ OR NORTH AMERICA INC.

July 11, 1967

Dr. William Haddon, Jr. Director National Highway Safety Bureau

Re.: Application for Binding Ruling Standard 201, provisional July 6, 1967, Armrests S 3.4.1 (b).

As indicated in the discussion of the proposed language on July 9, 1967, we are applying for a ruling that the definition of "rigid material" in line 4 shall be understood not to include such supporting structures of armrests which are made of flexible spring steel when such supporting structure designed to flex in the direction of transverse impact upon the pelvic impact area, and shall therefore not be subject to the requirement of "minimum vertical height of not less than 1"."

Argument: There are numerous armrest designs which may not qualify under the requirements of S 3.4.1(a) since they are at some part less than 2" wide laterally, and therefore must qualify under Para. (b). If such armrests are designed to combine the function of a door opener, i.e. with a fingerhole, a flexible spring core is ideally suited and has many times been used as a demonstrably safe design in the past. The spring material, which need not necessarily be steel but may also take the form of various plastics, provides the necessary strength for vertical support required for an armrest but gives upon transverse impact to avoid injury.

We should be grateful to receive your ruling at the earliest possible date in view of current production schedules for the 1968 models, and in view of the fact that with this indication we agreed to wave further amending language of the standard Para. S 3.4.1 (b), so as to provide for the possibility of clear definitions in some future revisions.

Respectfully,

H. C. Hoppe

ID: nht79-4.9

Open

DATE: 07/17/79

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: Daniel K. Akaka; House of Representatives

TITLE: FMVSR INTERPRETATION

TEXT: This responds to your June 21, 1979, telephone request asking how automobile dealers can determine when they must sell school buses as opposed to regular vans.

The key factors in making this determination are the purpose for which the vehicle will be used and the passenger carrying capacity of the vehicle. The National Highway Traffic Safety Administration (NHTSA) issued the school bus safety standards in response to the Motor Vehicle and Schoolbus Safety Amendments of 1974 (Pub. L. 93-492). In defining "schoolbus", Congress drew upon NHTSA's definition of "bus", i.e., any motor vehicle, including a van, designed to carry more than 10 persons. Congress stated that the term "schoolbus" means "a passenger motor vehicle which is designed to carry more than 10 passengers . . . and which the Secretary determines is likely to be significantly used for the purpose of transporting . . . students to or from school or events related to such schools." The NHTSA concluded from this mandate that any vehicle that is a bus and will be used on a regular and recurring basis to transport school children must comply with school bus safety standards. To effect this conclusion, the agency issued a definition of "schoolbus" which is "a bus that is sold or introduced in interstate commerce, for purposes that include carrying students to or from school or related events . . . ."

The effect of the 1974 amendments and the agency's definition is to require any new bus that is sold to transport school children on a regular basis to comply with the safety standards. Compliance is required whether a bus is used regularly to transport students 100 percent of the time or whether it regularly transport students only 10 percent of the time while otherwise transporting adults.

ID: nht76-3.34

Open

DATE: 06/22/76

FROM: T. W. HERLIHY FOR S. P. WOOD -- NHTSA

TO: Wisconsin Trailer Company Inc.

TITLE: FMVSR INTERPRETATION

TEXT: This responds to your June 2, 1976, request for written notification that the "heavy hauler trailer" exclusion of Standard No. 121, Air Brake Systems, has been extended to September 1, 1977. You also request confirmation that manufacturers may assign multiple gross vehicle weight ratings (GVWR) and gross axle weight ratings (GAWR) in fulfilling their responsibilities under Part 567, Certification (49 CFR Part 567) of our regulations, but that only ratings unqualified by speed restrictions will be permitted after September or October 1976.

I have enclosed a copy of the amendment that extends the "heavy hauler" exclusion of Standard No. 121 from September 1, 1976, to September 1, 1977. The date change in that amendment has been circled.

The NHTSA requires that the GVWR and GAWR placed on the certification plate in accordance with Part 567 be unqualified by speed restriction and be based on the 60-mph capabilities assigned to the tire and rims by the United States Tire and Rim Association. Other GVWR and GAWR values may be assigned by the manufacturer, but they must be listed after the information required on the Part 567 certification plate, and they do not form the basis of a vehicle's compliance with safety standards such as Standard No. 121.

In our November 20, 1975, letter to you on the same subject, we noted that we were considering a revision of the definition of GVWR and GAWR to conform to this interpretation. That proposal has been issued and a copy is enclosed for your information.

The proposal has not been made final as of the date of this letter. Please note that multiple ratings would continue to be permitted under the proposal, so long as the restricted rating appears first on the certification plate.

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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