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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 5821 - 5830 of 16490
Interpretations Date

ID: 9220

Open

Ms. Amantha L. Barbee
Sales Coordinator
Thomas Built Buses, Inc.
Post Office Box 2450
High Point, NC 27261

Dear Ms. Barbee:

This responds to your letter to me of October 14, 1993, and your telephone conversation with Walter Myers of my staff on October 22, 1993.

You stated in your letter that you are the Head Start Sales Coordinator for Thomas Built Buses, Inc., and in that capacity you have found that many Head Start agencies are using conventional vans to transport Head Start students to and from their programs. You stated that when you asked the directors of the agencies why they did not use vehicles that comply with Federal motor vehicle safety standards (FMVSS) for school buses, their usual answer was "because we have not been told otherwise." You then asked whether this practice is illegal and if so, what your organization can do to rectify the situation.

As Mr. Myers explained in your telephone conversation, this agency has repeatedly stated that Head Start facilities are preprimary schools. Therefore, new buses sold to Head Start centers for use in transporting Head Start participants to and from school must comply with all Federal motor vehicle safety standards applicable to school buses. However, Federal law does not require Head Start facilities to use complying school buses or any other particular vehicles. The individual states, not the Federal government, have authority over the use of vehicles.

As promised by Mr. Myers, please find enclosed interpretation letters previously issued by us on this issue, as follows: to Hon. Paul David Wellstone, U.S. Senate, dated Jan. 26, 1993; to Mr. Chuck Anderson, dated Aug. 21, 1992; and to Mr. Charles Pekow, dated Sept. 27, 1985.

I hope this information will be useful. If you have any further questions or desire any further information, please feel free to contact Mr. Myers at this address or at (202) 366-2992.

Sincerely,

John Womack Acting Chief Counsel Enclosures

ref:571#102 d:11/23/93

1993

ID: nht74-2.8

Open

DATE: 11/06/74

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: Truck Body and Equipment Association, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your October 3, 1974, questions whether the exemption for 24,000-pound axle vehicles from Standard No. 121, Air brake systems, until September 1, 1976, applies to fire fighting vehicles, and whether a tandem axle assembly consits of two "axle systems" for purposes of our definition of "Gross axle weight rating."

The answer to both of your questions is yes. A fire fighting vehicle would qualify for exemption until 1976 if any of its axles has a gross axle weight rating of 24,000 pounds or more.

A tandem axle assembly, which we understand to mean a running rear assembly consisting of two axles and associated components, comprises two "axle systems." As we pointed out in the preamble to Notice 2 of Docket No. 74-10, the term "axle system" is used only to avoid confusion in situations where a suspension system does not employ an axle (39 FR 17550, May 17, 1974).

Yours truly,

ATTACH.

TRUCK BODY AND EQUIPMENT ASSOCIATION, (Illegible Word)

October 3, 1974

Richard Dyson -- Office of Chief Council, National Highway Traffic Safety Administration

Dear Mr. Dyson:

Recently several members of our Fire Apparatus Manufacturers Division have contacted us with questions concerning FMVSS 121 and its effective date. In order that we may accurately answer these questions, we would like the following clarified.

(1) Does a fire apparatus qualify for the "Special Permit Vehicle" classification if it is equipped with an axle with a GAWR equal to or greater than twenty-four thousand pounds (24,000 lbs.)?

(2) Is a tandem axle assembly comprised of two "Axle Systems", per your GAWR definition?

Your cooperation in this matter is greatly appreciated.

Sincerely yours,

Byron Crampton -- Manager of Engineering Services

ID: nht81-2.25

Open

DATE: 05/12/81

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Gregory Equipment & Manufacturing Co.

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of April 13, 1981, with respect to placement of identification lamps on the boat trailer you wish to manufacture.

You have informed us that the trailers are not built for transporting boats on the highways and your sales sheet reiterates that point: "These trailers are for in marina use only. Not for over the road use." Under the National Traffic and Motor Vehicle Safety Act, a vehicle that is not manufactured primarily for use on the public roads is not a vehicle subject to our regulations. From your letter and advertising enclosure, it appears that your intent is to build a vehicle that will be used primarily on private property. Therefore, our lighting requirements would not apply to it.

I hope that this answers your question.

SINCERELY,

Gregory Equipment & Manufacturing Co.

April 13, 1981

Chief Consul National Hwy. Traffic Safety Administration

Dear Sir;

I would like a ruling on the 3 cluster light for the rear of trailers. The boat trailer we are starting to manufacture doesn't have a place which such light may be mounted as shown in Picture #1. If lights were placed on the rear they would be jammed into the mud in the bottom of the river as shown in picture #2.

These lights are for the movement of the empty trailers from the plant to the sales designation. These are not built for transporting boats on the highways.

Inclosed is a brouchure. The trailer in this brochure is not equiped with lights because it is our prototype.

If any further information is needed please call me at 319-372-5314.

James E. Gregory

ID: aiam4850

Open
Mr. Saburo Inui Corporate Manager Toyota Motor Corporate Services of North America, Inc. 1850 M Street, N.W. Washington, D.C. 20036; Mr. Saburo Inui Corporate Manager Toyota Motor Corporate Services of North America
Inc. 1850 M Street
N.W. Washington
D.C. 20036;

Dear Mr. Inui: This responds to your letter of February 20, 1991, wit respect to an interpretation of Standard No. 108 as it relates to High Intensity Discharge Headlamp (HID) designs contemplated by Toyota. You explained these designs in greater detail to NHTSA staff members in a meeting with them on February 20. Standard No. 108 defines an 'integral beam headlamp' as one which is neither a sealed beam headlamp nor one equipped with a standardized replaceable light source, but one which is a 'headlamp comprising an integral and indivisible optical assembly, including lens, reflector, and light source.' You have presented two HID headlamp designs, and have asked whether these lamps are 'integral beam headlamps' as defined by Standard No. 108. These lamps differ from conventional headlamps by having ballast, consisting of a 'starter' affixed to the rear of the headlamp, connected to a 'converter,' which is separated from the headlamp-starter unit. Because of space limitations, it may not be feasible to integrate the ballast into the headlamp enclosure. On one of these headlamps (Figure 2) the starter and converter are directly connected to each other by a 'hard wire' while in the other (Figure 3), the starter and converter are connected by 'hard wires' that meet at a connector between the two. In this design, the ballast units would be installed separately, then permanently joined by a connector, which could not be separated without destroying the connector. You believe that both designs are 'integral beam headlamps.' The phrase 'optical assembly' in the definition of 'integral beam headlamp', in our view, encompasses all lamp components other than the power source which are required for illumination of the headlamp. This means that an 'optical assembly' includes the ballast. Although the lamp, starter, and converter may be permanently attached to each other, and could be considered 'indivisible,' and the starter could be considered to be 'integral' with the lamp body, the positioning of the converter at some distance from the starter, as shown in your Figure 2 and Figure 3, does not render it 'integral' within the meaning of the definition, unless it is permanently attached to the starter. However, a design which had a connector as in your Figure 3 and described in your letter, would be considered both 'integral' and 'indivisible' if its individual components were not permanently attached to each other until the installation of the device in a motor vehicle, providing that any portion of the device could not be subsequently detached without damage sufficient that the entire device would have to be replaced. This would apply to either original or replacement equipment. Sincerely, Paul Jackson Rice Chief Counsel;

ID: nht74-5.22

Open

DATE: 04/12/74

FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA

TO: Driver and Vehicle Administration; Michigan Department of State

TITLE: FMVSR INTERPRETATION

TEXT: Some time ago you asked our regional office in Chicago for advice concerning the sufficiency of the odometer disclosure form developed by Michigan for use on its certificates of title and other motor vehicle transfer documents. This will serve to confirm the informal opinion you received from Dick Cook of the regional staff.

As pointed out in the letter sent you by General Motors, the Michigan form lacks certain informational items that are specified in the Federal odometer disclosure regulation. To comply fully with the regulation, the Michigan form would have to include space for the vehicle model and the last plate number. However, we do not regard the absence of these items to be serious enough to mandate a change in the Michigan form, in that the other information provided on the form appears sufficient to accurately identify the vehicle. A transferor who completes the present form and thereby fails to give the additional information would not be misleading the transferee and would therefore not be subject to civil action under the Act. It is our view that a transferor who completes the disclosure statement on the Michigan form would not need to submit an additional disclosure form.

ID: aiam0685

Open
Mr. W.G. Milby, Project Engineer, Blue Bird Body Company, Fort Valley, GA 31030; Mr. W.G. Milby
Project Engineer
Blue Bird Body Company
Fort Valley
GA 31030;

Dear Mr. Milby:#This is in reply to your letter of April 19 to Mr Schneider asking for interpretations of the motor vehicle controls safety standard, Standard No. 101.#You have asked that we reconsider our earlier opinion that your heater gate valve is a 'heating and air conditioning system control' for purposes of Standard No. 101. We see no reason to modify our earlier view. A control, as you have described it, that allows hot engine water to flow through the heater cores is clearly a heating system control, requiring identification as such. Table I of Standard No. 101 allows you the option of choosing your own form of identification. Perhaps a legend such as 'Water Control' and a designation of 'Winter' and 'Summer' positions would clarify your intent that the valve not be used as a temperature control device. However, pursuant to paragraph S4.3 this control need not be illuminated, if, as appears likely, it does not direct air directly upon the windshield.#You have also asked if the cable- operated fresh air door whose function is to control the air that passes through the heater cores is also a 'heating and air conditioning control.' It appears that this control serves a function similar to that of the heater valve, and that identification is also required, with words or abbreviation at the manufacturer's option.#Finally, you ask if the defroster identification may be preceded by 'RH' and 'LH' to identify the right hand and left hand defroster systems respectively. The answer is yes, we have no objection to this form of identification.#Yours truly, Richard B. Dyson, Assistant Chief Counsel;

ID: aiam4554

Open
CONFIDENTIAL; CONFIDENTIAL;

"Dear: This is in reply to your letters of July 12, and September 2 1988. In accordance with your request for confidentiality on the basis that your letter of July 12 contains confidential business information, your name, your company's name and address, and the name of the product concerned will be deleted from copies of this interpretation that are made publicly available. Your company wishes to install a leveling device that will lower the height of a motor vehicle to facilitate entry. It can be activated only when the parking brake is applied and the vehicle is at rest. Normal vehicle height is restored by driver activation of a control when the ignition is in the 'on' position. Should the operator attempt to drive away without activation of the control, release of the parking brake or registration of motion by a speed sensor ensures that normal vehicle height is restored within approximately l5 seconds. You state that the vehicle will conform to all applicable Federal motor vehicle safety standards 'when the vehicle is in its configuration for operation on public roads..., meeting all the requirements relevant to height (i.e., lighting device mounting heights, rear view mirror fields of view, non passenger car CAFE' categorization, and the like). You believe that incorporation of the height adjuster feature should not be considered when determining compliance with either the Federal motor vehicle safety standards, or the vehicle's classification for fuel economy purposes, except for mounting height requirements for lighting equipment designed to be used while the vehicle is stationary (such as parking lamps and hazard warning signal lamps). You ask for our concurrence in this interpretation. Your interpretation is acceptable to us. Provision of the feature described would not invalidate the certification of your company that the vehicle complies with all applicable Federal motor safety standards. We note that the adjustment in height is not automatic, but at the discretion of the vehicle operator. Further, the height adjuster is designed so that if it depresses vehicle height while a vehicle is being operated, it would do so only temporarily, i.e., not more than 15 seconds. Similarly, the height adjuster would not lead to a change in the classification of your vehicle for purposes of the fuel economy standards. Although 49 CFR 523.5 clearly indicates that measurement of angles and clearances for automobiles capable of off-highway operation is to be made when a vehicle is at rest, and your vehicle apparently would not have the requisite angles and clearances when the height adjuster is activated, it would have those angle and clearance when the adjuster is not activated. Further, activation of this feature is discretionary and its effects on the vehicle in motion are, as already noted, very brief. Thus, the vehicle would have the requisite clearance almost all of the time while it is being operated. Sincerely, Erika Z. Jones Chief Counsel";

ID: nht68-2.26

Open

DATE: 10/29/68

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

TO: Messrs. Hogan & Hartson

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your letter of October 17 asking several questions about the importation of motor vehicles and equipment items attached to them after entry and prior to sale.

The Joint Regulations (19 C.F.R. S12.80) are clear as to the points you raise. Subsection(b)(2)(iv) allows the entry of a vehicle bearing a not-yet-valid certification plate upon the filing of a declaration that:

"Such vehicle is a new vehicle being imported for purposes of resale which does not presently conform to all applicable standards because readily attachable equipment items are not attached, but that there is affixed to its windshield a label stating the standard with which and the manner in which such vehicle does not conform end that the vehicle will be brought into conformity by attachment of such equipment items before it will be offered for sale to the first purchaser for purposes other than resale."

The regulations require separate labels for each vehicle since it is the individual vehicle, and not the lot, which does not conform.

(Illegible word) @ 12.08(c) indicates, a release under the bond is required only when declaration is filed pursuant to subsection (b)(2)(iii) and not subsection (b)(2)(iv).

ID: aiam3150

Open
Mr. T. Fujita, Manager, Automotive Lighting, Engineering Department, Stanley Electric Co., Ltd, 2-9-13, Nakameguro Meguro- ku, Tokyo 153, Japan; Mr. T. Fujita
Manager
Automotive Lighting
Engineering Department
Stanley Electric Co.
Ltd
2-9-13
Nakameguro Meguro- ku
Tokyo 153
Japan;

Dear Mr. Fujita: This is in reply to your letter of October 17, 1979, asking for a interpretation for Paragraph S4.3.1.7 of Federal Motor Vehicle Safety Standard No. 108.; S4.3.1.7 says in effect that a front turn signal lamp and a low bea headlamp may be closer to each other than 4 inches 'if the sum of the candlepower values of the turn signal lamp measured at the test points within each group listed in Figure 1 is not less than two and one-half times the sum specified for each group for yellow turn signal lamps.'; You have asked whether a motorcycle turn signal lamp should 'satisf the values specified in S4.3.1.7 or half those values'. The answer, is, the values specified in S4.3.1.7. Half those values would be 'less than two and one-half times the sum specified ...' and impermissible under S4.3.1.7.; I hope that this answers your question. Sincerely, Frank Berndt, Chief Counsel

ID: aiam5604

Open
Ms. Yvonne Anderson Todd Vans East Highway 28 Morris, MN 56267; Ms. Yvonne Anderson Todd Vans East Highway 28 Morris
MN 56267;

"Dear Ms. Anderson: This responds to your letter of July 13, 1995 concerning a van which your company is modifying. The van is owned by a local school system. The school system has asked your company to raise the roof, extend the side door, install wheelchair tiedowns, and install a wheelchair lift. The vehicle was certified as a 'bus,' but your modification would reduce the seating capacity so that the vehicle would become a 'multipurpose passenger vehicle' (MPV). You asked whether this vehicle must be certified following the modifications. The answer to your question is no. By way of background information, the National Highway Traffic Safety Administration (NHTSA) is authorized to issue Federal motor vehicle safety standards that apply to the manufacture and sale of new motor vehicles. A vehicle must be certified as complying with all applicable safety standards before it can be sold or imported. After the first retail sale, there is a limit on modifications made to vehicles. Manufacturers, distributors, dealers, and repair businesses are prohibited from 'knowingly making inoperative' any device or element of design installed on or in a motor vehicle in compliance with an applicable safety standard (49 USC 30122). In general, the 'make inoperative' prohibition would require a business which modifies motor vehicles to ensure that they do not remove, disconnect, or degrade the performance of safety equipment installed in compliance with an applicable safety standard. I hope you find this information helpful. If you have any other questions, please contact Mary Versailles of my staff at this address or by phone at (202) 366-2992. Sincerely, John Womack Acting Chief Counsel";

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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