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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 901 - 910 of 16517
Interpretations Date

ID: aiam3170

Open
Mr. John F. Croonquist, President, Alternative Automotive, Inc., 999 N. Pacific Street, 33-D, Oceanside, CA 92054; Mr. John F. Croonquist
President
Alternative Automotive
Inc.
999 N. Pacific Street
33-D
Oceanside
CA 92054;

Dear Mr. Croonquist: This responds to your November 9, 1979, letter asking whether a vehicl that you plan to produce would be classified as a truck for purposes of applying the Federal motor vehicle safety standards.; In your letter, you state that your vehicle looks somewhat like a Jeep You state further that it is constructed on a Volkswagen truck chassis, carries two passengers, and is designed to transport property. As you know, the agency defines truck to be a vehicle that is designed primarily to transport property or speciality (sic) equipment. Since the vehicle that you plan to manufacture appears to be designed for the transportation of property and since it is constructed on a truck chassis, the agency concludes that it would be a truck for the purposes of applying the safety standards.; Sincerely, Frank Berndt, Chief Counsel

ID: aiam3520

Open
H. A. Kendall, Ph.D., Executive Secretary, United Sidecar Association, Inc., 1621 Palomino Lane, Kingwood, TX 77339; H. A. Kendall
Ph.D.
Executive Secretary
United Sidecar Association
Inc.
1621 Palomino Lane
Kingwood
TX 77339;

Dear Dr. Kendall: This is in reply to your letter of September 9, 1981, asking severa questions about Federal Motor Vehicle Safety Standard No. 108.; You have asked for a clarification of our position on pulsatin headlamps and stoplamps, commenting that several States have expressed a concern 'that a light of variable intensity may be confused by the citizen as an emergency vehicle which is allowed to have flashing headlights.'; As you have indicated, paragraph S4.6(a) of Standard No. 108 require turn signal lamps, hazard warning signal lamps, and school bus warning lamps to flash when activated, while S4.6(b) requires all other lamps to be steady burning. By 'steady burning,' the standard means a light that is essentially unvarying in intensity. There is, however, an exception in S4.6(b) to the 'steady burning' requirement. Means may be provided 'to flash headlamps and side marker lamps for signalling purposes.' Paragraph S3 of the standard defines 'flash' as meaning 'a cycle of activation and deactivation of a lamp by automatic means....' In our view, a lamp whose intensity varies from a higher output to a lower output would not be 'steady burning' or 'flash' within the meaning of those terms and hence would be prohibited. But if complete deactivation occurs, then the lamp 'flashes.' Installation of flashing lamps under the S4.6(b) exception is not restricted to emergency vehicles. It is permissible under the standard for a motorcycle to have a device which gives the motorcyclist the option of causing a motorcycle headlamp to operate automatically through cycles of activation and deactivation instead of burning steadily.; On the other hand, stop lamps that either flash or are of variabl intensity are not allowed by S4.6(b) of Standard No. 108 since they are not steady-burning while in use.; I hope this answers your questions. Sincerely, Frank Berndt, Chief Counsel

ID: 05-Turnquist_drn

Open

    Mr. Harold V. Turnquist
    Transportation Administrator
    1780 West 7th Street
    Saint Paul, MN 55116-2347


    Dear Mr. Turnquist:

    This responds to your letter requesting confirmation that there has been no change since 1998 in the National Highway Traffic Safety Administration (NHTSAs) position regarding use of 15-passenger vans by your districts Early Childhood Family Education (ECFE) program. In an April 29, 1998, letter to you, then Acting Chief Counsel John Womack stated that NHTSA does not consider the ECFE program to constitute a "school" as that term is used in our statute. Mr. Womack concluded that new buses leased to you for transporting ECFE Program participants were thus not required to be school buses under Federal law.

    Assuming the ECFE program has not changed, we confirm that we still believe that the instruction in developing the participants parenting skills are distinct from the academic instruction associated with a "school", and that we thus do not consider the ECFE program to be a "school" for purposes of our regulations. Accordingly, if a dealer were to sell or lease a new 15-passenger van to the Saint Paul Public Schools Community Education Department for the exclusive use of the ECFE program, that dealer need not sell or lease a new school bus.

    Nonetheless, there have been developments in the last few years regarding the use of 15-passenger vans, and we appreciate the opportunity to bring these to your attention.

    15-Passenger Van Rollover Risk

    The way some 15-passenger vans may be driven may subject occupants to an increased risk of rollover crashes. On June 1, 2004, NHTSA Administrator Jeffrey W. Runge, M.D. , reissued a cautionary warning to 15-passenger van users because of an increased rollover risk under certain conditions. NHTSA research has shown that 15-passenger vans have a rollover risk that increases dramatically as the number of occupants increases from fewer than five to more than ten. In fact, 15-passenger vans with 10 or more occupants had a rollover rate in single-vehicle crashes that is nearly three times the rate of those that were lightly loaded.

    Dr. Runge advised 15-passenger van users to be aware of the following safety precautions in order to significantly reduce the rollover risk:

    • It is important that 15-passenger vans be operated by trained, experienced drivers.
    • All occupants must wear seat belts at all times. Eighty percent of those who died in 15-passenger van rollovers nationwide in the year 2000 were not buckled up. Wearing seat belts dramatically increases the chances of survival during a rollover crash. In fatal, single-vehicle rollovers involving 15-passenger vans over the past decade, 92 percent of belted occupants survived.

    I am enclosing copies of the consumer advisory and a flyer, "Reducing the Risk of Rollover Crashes in 15-Passenger Vans".

    The Multifunction School Activity Bus

    In 2003, NHTSA established a new school bus subcategory, the "multifunction school activity bus" (MFSAB). This vehicle is a bus that meets all Federal motor vehicle safety standards for school buses except those for school bus flashing lights and stop arms. MFSABs are sold for purposes that do not include transporting students to and from home or school bus stops. Federal law permits the sale of new MFSABs to child care facilities as an alternative to school buses with flashing lights and stop arms. A copy of a July 31, 2003, final rule that establishes the vehicle category is enclosed for your information.

    I hope this information is helpful. If you have any further questions, please feel free to contact us at 202-366-2992.

    Sincerely,

    Jacqueline Glassman
    Chief Counsel

    Enclosures
    ref:VSA
    d.3/14/05

2005

ID: 0513

Open

Mr. Yoshiaki Matsui
Manager, Legal & Homologation Section
Stanley Electric Co. Ltd.
2-9 13, Nakameguro, Meguro-ku
Tokyo 153, Japan

Dear Mr. Matsui:

We have received your letter of November 16, 1994, to Patrick Boyd of this agency, asking for an interpretation of the final rule that amended Motor Vehicle Safety Standard No. 108 on November 2, 1994.

The rule amended S5.1.2(c) to specify, in pertinent part, that "after the outdoor exposure test, plastic materials used for reflex reflectors . . . shall not show . . . haze that exceeds 7 percent . . . ." The amendment is effective November 1, 1995. You have presented two fact situations with respect to replacement reflex reflectors, and ask whether the amended haze requirement is applicable in each case. These are:

"First case - replacement reflex reflectors manufactured after the effective date, but the vehicle to which the reflex reflectors are fitted is no longer manufactured after the effective date."

Motor vehicle replacement equipment is governed by S5.8 of Standard No. 108. S5.8.1 requires that any reflective device manufactured to replace any reflective device on any vehicle to which Standard No. 108 applies shall be designed to conform to Standard No. 108. Paragraphs S5.8.2 through S5.8.9 permit certain specified items of replacement equipment to be manufactured to original equipment specifications (e.g., earlier versions of SAE standards no longer specified for original equipment on motor vehicles); however, reflex reflectors are not included among them. This means that any reflex reflectors manufactured on and after November 1, 1995, whether original or replacement, must conform with the 7 percent haze limitation, regardless of the date of manufacture of the vehicle.

"Second case - Replacement reflex reflectors manufactured before the effective date, which may be

fitted to a vehicle manufactured before or after the effective date. (In this case, the same type of vehicles are manufactured before and after the effective date continuously.)"

A replacement reflex reflector manufactured before November 1, 1995, to replace a reflex reflector on a vehicle manufactured either before or after November 1, 1995, is subject to the requirement that the plastic materials used in them shall show no haze in a visual inspection after the outdoor exposure test because that is the requirement in effect at the time the replacement reflex reflector is manufactured.

As a practical matter, it would appear to make no difference when the reflector was manufactured or to which specification. The amendment is not intended to change manufacturing techniques or composition of plastics materials in any way. Because it is impossible not to have some degree of haze at the end of the three-year test period, Standard No. 108 was amended to make it more objective and practicable, and the measured haze limit raised to 7 percent, at which point haze is visible to the naked eye.

Sincerely,

Philip R. Recht Chief Counsel

ref:108 d:12/7/94

1994

ID: 0533

Open

Mr. Michael Love
Manager, Compliance
Porsche Cars North America, Inc.
P.O. Box 30911
Reno, Nevada 89520-3911

Dear Mr. Love:

We have received your letter of November 29, 1994, asking for an interpretation of 49 CFR Part 591.

Specifically, Porsche wishes to import vehicles for the Canadian market through the Port of Charleston, where certain processing activities will be performed on the cars before they are exported to Canada. The temporary importation of Canadian-market cars would be through 591.5(c) which allows importation "solely for export", provided that the vehicle is so labeled. You have asked for our concurrence in your interpretation of 591.5(c). We agree that Porsche may import and export Canadian-market cars under this section of the importation regulation.

You foresee a situation in which "a Canadian vehicle with a unique combination of options might be sought by a U.S. customer". Porsche would like to be able to convert the vehicle to comply with the U.S. Federal motor vehicle safety standards after importation and before it leaves Porsche's control. Porsche would also like to be able to re-import from Canada into the U.S. vehicles that would be converted to U.S. specifications. You have asked for confirmation that these operations would also be permissible under 591.5(c).

Importation of noncomplying motor vehicles into the United States and their subsequent conversion to the U.S. Federal motor vehicle safety standards must be accomplished through the mechanisms established by Congress in the Imported Vehicle Safety Compliance Act of 1988 (now 49 U.S.C. 30141 et seq.). First, NHTSA must have decided that the vehicle is eligible for importation pursuant to 49 CFR Part 593. Second, a vehicle intended for sale must be imported under bond by one who has been designated a Registered Importer under 49 CFR Part 592, who will undertake to bring the vehicle into compliance and to submit appropriate proof of this to NHTSA. Porsche may become a Registered Importer by filing an application under Part 592.

If a vehicle intended for the Canadian market has been temporarily imported under 591.5(c), and Porsche then wishes to convert it to U.S. specifications rather than export it to Canada, you should telephone Clive Van Orden, Office of Vehicle Safety Compliance (202-366- 2830), to apprise him of the situation. We see no problem in this as long as NHTSA has decided that the vehicle is eligible for importation and Porsche provides a compliance package, in accordance with the requirements of Parts 592 and 593.

Sincerely,

Philip R. Recht Chief Counsel ref:591#592#593 d:12/22/94

1994

ID: 0552

Open

Ms. Melinda Dresser
Manager Contracts/Transportation
Carlin Manufacturing, Inc.
3714 N. Valentine
Fresno, CA 93722

Dear Ms. Dresser:

We have received your letter of November 28, 1994, asking whether the exterior lighting of six Oscar Mayer "Wienermobiles" that your company is manufacturing conforms to applicable Federal motor vehicle safety standards. You have enclosed diagrams showing the location of the exterior lighting devices.

Under 49 U.S.C. Chapter 301 - Motor Vehicle Safety, the determination of whether a vehicle conforms with all applicable Federal motor vehicle safety standards is that of the manufacturer who, pursuant to 49 U.S.C. 30115, must certify compliance of the vehicle with those standards upon completion of manufacture. NHTSA has no authority to approve or disapprove specific vehicle designs. We do, however, provide interpretations of our standards to manufacturers upon request. The appropriate standard here is Motor Vehicle Safety Standard No. 108 Lamps, Reflective Devices, and Associated Equipment.

Your letter does not state whether Carlin has classified the Wienermobile as a "passenger car" or as a "truck". We believe that the vehicle is a "truck" within the meaning of 49 CFR 571.3(b) because it appears to be "designed primarily for the transportation of property or special purpose equipment", rather than for the transportation of passengers, and that its overall width of 94 inches makes it more appropriate for the Wienermobile to meet wide vehicle lighting requirements. Therefore, the Wienermobile must be equipped with the lighting equipment specified in Table I of Standard No. 108, and located as specified in Table II, the requirements for trucks whose overall width is 80 inches or more. This means that they must be equipped with the front and rear clearance and identification lamps that Table I requires for wide trucks; these lamps do not appear on your drawings.

In addition, all four-wheeled motor vehicles are required to have hazard warning/turn signal lamps and we don't see these

lamps either on the drawings. With respect to front lighting equipment that is depicted, we note that supplementary lighting equipment such as fog lamps and the "front marker light" are permissible under Standard No. 108 if the manufacturer determines that they do not impair the effectiveness of the lighting equipment required by Standard No. 108, in this instance, the headlamps. In the absence of a clearly erroneous determination, NHTSA will accept the manufacturer's judgment on impairment. Trucks that are subject to Table II need not be equipped with a center high- mounted stop lamp or parking lamps, if that is the purpose of the front marker lamp.

We hope that these comments will be helpful. If you have any other questions, please contact Mr. Taylor Vinson of my staff at this address or by phone at (202) 366-2992.

Sincerely,

Philip R. Recht Chief Counsel ref:108 d:1/9/95

1995

ID: 0566

Open

Mr. Gerard Bonvin
Auto Cheyenne USA Inc.
6611 1/2 West 6th Street
Los Angeles, CA 90036

Dear Mr. Bonvin:

This is in reply to your letter of December 15, 1994, with respect to the relationship of certain DOT regulations to the Cheyenne, a small front-wheel drive utility vehicle that you wish to import and distribute in the United States.

You have asked the following questions:

"What are the procedure to follow in order to be categorize Small Volume manufacturer?"

Your question assumes that we have a category of "small volume manufacturer." We do not, and there is no exclusion from the Federal motor vehicle safety standards (FMVSS) based upon the volume produced by the manufacturer. All motor vehicles must comply with all FMVSS, unless the agency has exempted them from one or more of the standards. We do recognize limited production volume in the regulation under which a manufacturer who produces less than 10,000 motor vehicles of all types may apply for a temporary exemption on the basis that compliance would cause it substantial economic hardship, and must provide production information as part of its application.

"Is there really a big difference on the test in order to certified between small volume and over 10000 vehicles?"

As indicated above, if a manufacturer produces less than 10,000 vehicles, that fact is relevant only if that manufacturer wishes to file a hardship exemption application. If a small volume manufacturer has not been exempted, it must comply with the same requirements as apply to those whose yearly production exceeds 10,000.

"Is there any difference between two seaters or four seaters on crash test?"

That is a question to be answered by a vehicle manufacturer. If a four-seater is heavier than a two- seater, the difference

in weight could make a difference in whether a vehicle with a borderline design passes or fails a crash test.

"Is there a rear crash impact?"

Yes. FMVSS No. 301 Fuel System Integrity specifies a 30 m.p.h. moving barrier rear impact test.

"Do we need Air Bags if we have Seat belts?"

Currently, vehicles like the Cheyenne are not required to have air bags. However, as explained below, air bags are one means of complying with a the automatic protection requirement which is being phased in for vehicles like the Cheyenne, and eventually the Cheyenne will be required to have air bags for both the driver and right front passenger.

Generally, Jeep-type vehicles are considered to be "multipurpose passenger vehicles" (MPVs). Based on your description, we also assume that the Cheyenne will have a GVWR of 8,500 pounds or less. A requirement in FMVSS No. 208, Occupant Crash Protection, which is being phased in requires a specified percentage (varying by year) of each manufacturer's light trucks (a category which includes MPVs with a GVWR of 8,500 pounds or less) manufactured on or after September 1, 1994 to be equipped with automatic crash protection. The two types of automatic crash protection currently offered are automatic safety belts and air bags.

A recent amendment of FMVSS No. 208 will require at least 80 percent of each manufacturer's light trucks manufactured on or after September 1, 1997 and before September 1, 1998 to be equipped with an air bag and a manual lap/shoulder belt at the driver's and right front passenger's seating positions. All light trucks manufactured on or after September 1, 1998 must be equipped with an air bag and a manual lap/shoulder belt at these seating positions.

"Do we need a buzzer for the seat belt?"

Yes, an audible warning indicator is required.

"Is the dashboard need to be padded?"

We cannot answer your question. That decision is to be made by the manufacturer if its tests show that the dashboard is within the head impact area and that some type of padding is necessary to meet FMVSS No. 201 Occupant Protection in Interior Impact. The FMVSS are performance standards and we do not impose design restrictions on the manufacturer, such as requiring that the dashboard be padded.

"Is there any specific ways on how to install the windshield?"

No, because that would be design restrictive and, as noted above, the FMVSS are performance standards. The performance requirement for windshields is in FMVSS No. 212 Windshield Retention which specifies what the windshield mounting must do in a 30 mph frontal barrier crash. However, if the MPV is an open vehicle with a fold-down windshield, FMVSS No. 212 does not apply to it.

"What is the surface of the windshield that need to wiped? As far as Windshield Wipers, how many cycles and how many different speed?"

You will find the answers to your questions in FMVSS No. 104 Windshield Wiping and Washing Systems. For a copy of these and all our regulations, you should have a copy of "Title 49 Code of Federal Regulations Parts 400-999". This is available from the U.S. Government Bookstore at ARCO Plaza, C-Level, 505 South Flower Street, Los Angeles.

Sincerely,

Philip R. Recht Chief Counsel

ref:555 d:2/2/95

1995

ID: 0572

Open

Mr. Kenneth Sghia-Hughes
Research Engineer
Solectria Corporation
68 Industrial Way
Wilmington, MA 01887

Dear Sir:

We have received your letter of December 8, 1994, with respect to the applicability of two Federal motor vehicle safety standards to electric vehicles.

With respect to Standard No. 301 Fuel System Integrity, you believe that the language of S3 implies that "it applies to all passenger vehicles, but to only those trucks with GVWR of 10,000 pounds or less and that use fuel with a boiling point above 32 degrees F." You conclude, however, that "this standard appears not to apply to electric vehicles with no liquid fuel."

Under S3 of Standard No. 301, the standard applies to certain specified vehicles that "use fuel with a boiling point above 32 degrees F". The use of the fuel is not stated. Obviously, electric vehicles do not use liquid fuel for propulsion, but some of them do use a small amount of liquid fuel in their heating systems. Standard No. 301 would apply to an electric vehicle with a fuel-fired heating system.

With respect to Standard No. 102 Transmission Shift Lever Sequence, Starter Interlock, and Transmission Braking Effect, you ask for "a clarification of this standard with regard to single speed transmissions" and, if it is applicable, ask that S3.1.3 "be rewritten or interpreted to include the initial activation of EV motor controllers as well as engine starters."

NHTSA has previously concluded that electric vehicles with single speed transmissions are excluded from Standard No. 102 (58 FR at 4646). I enclose a copy of the Federal Register notice reflecting this conclusion.

Sincerely,

Philip R. Recht Chief Counsel

Enclosure ref:102#301 d:2/2/95

1995

ID: 0573

Open

Mr. R. F. Wareham
Technical Director
Total Vehicle Security, Ltd.
1 Friarn Lawn
Bridgwater
Somerset TA6 3LL
England

Dear Mr. Wareham:

We have received your letter of December 9, 1994, to John Womack, the Acting Chief Counsel who responded to David Lee on January 26, 1993. This will confirm that his opinion regarding the "Third Brake Light Conditions Sensor" remains the official position of this agency.

We shall be pleased to meet with you when you come to Washington late in January. You may phone Taylor Vinson of this Office to make arrangements (202-366- 5263). We will be particularly interested in learning more about how the device "will be marketed as a D.I.Y. installation by the car owner."

Sincerely,

Philip R. Recht Chief Counsel ref:108 d:12/21/94

1994

ID: 0596

Open

Mr. Michael A. Holmes
#503768, 7B10
Farmington Correctional Center
1012 West Columbia
Farmington, MO 63640-2902

Dear Mr. Holmes:

This responds to your letter of December 6, 1994, to the Secretary of Transportation, regarding the laws that apply to the manufacture of cars and light trucks. You have a design which you describe as "hydrogen turbine over electric."

The principal law that the Department of Transportation administers that pertains to the construction of motor vehicles is Title 49 United States Code Chapter 301 - Motor Vehicle Safety. Under its authority, we have issued the Federal Motor Vehicle Safety Standards and other pertinent regulations. These are available from the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 at an invoiced cost of around $25. The title of the volume you want is "49 CFR Parts 400-999"; all our regulations are in the 500 series. The Safety Standards are at Part 571. The applicability section of each standard informs the reader as to the types of vehicles to which it applies, such as passenger cars, motorcycles, etc. However, the standards don't differentiate between propulsion sources, and there are no standards that apply to "electric vehicles," or, in your case, "hydrogen turbine over electric."

You should be aware that the Environmental Protection Agency establishes standards for motor vehicle emissions, and that the individual States are permitted to have their own standards in areas where the Department of Transportation has not acted, such as horns and fog lamps.

If you have any further questions, they should be directed to this Office and we will be pleased to answer them.

Sincerely,

Philip R. Recht Chief Counsel ref:571 d:1/11/95

1995

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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