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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 14251 - 14260 of 16490
Interpretations Date

ID: nht92-2.40

Open

DATE: 11/09/92

FROM: PAUL JACKSON RICE -- CHIEF COUNSEL, NHTSA

TO: CHRISTOPHER LEONE -- NEWBOLD DESIGNS

ATTACHMT: ATTACHED TO LETTER DATED 8-6-92 FROM CHRISTOPHER LEONE TO TAYLOR VINSON

TEXT: This responds to your FAX of August 6, 1992, to Taylor Vinson of this Office, asking for rules and regulations of the Department on electric vehicles. I understand that you talked with Mr. Vinson later in the day, and received an overview of the matter. I further understand that you intend only the construction of a single experimental vehicle, and have no plans for its production.

Under the National Traffic and Motor Vehicle Safety Act, the introduction into interstate commerce, by any person, of a motor vehicle that does not conform to all applicable Federal motor vehicle safety standards is a violation, for which a civil penalty of up to $ 1,00 may be imposed. The Federal motor vehicle safety standards are set out in Title 49 Code of Federal Regulations Part 571. There are no standards that apply to your project car are those that apply to "passenger cars" in general.

However, the manufacturer of an electric vehicle may petition us for a temporary exemption (up to 2 years) from one or more of the safety standards on the basis that the exemption would facilitate the development and field evaluation of a low-emission motor vehicle. The temporary exemption regulations are found at 49 CFR Part 555. An exemption covers up to 2,500 vehicles per year for any 12-month period that the exemption is in effect.

Regulations governing the licensing of motor vehicles are the prerogative of the individual States. Thus, you should inquire as to what Rhode Island requires for your contemplated vehicle.

There is a regulatory gap which your situation highlights, and that is the legal status of a person who intends to build only a single motor vehicle. Such a person is not a "manufacturer" under the Act, since the operative portion of the definition of "manufacturer" is one who manufactures or assembles "motor vehicles". The temporary exemption authority appears directed towards commercial enterprises and not single motor vehicles. Nevertheless, we believe we have the authority to exempt a single motor vehicle under these provisions.

If you wish to consult us further in this matter, Taylor Vinson will be pleased to help you.

ID: nht79-4.46

Open

DATE: 08/21/79

FROM: LEO BACHYNSKY -- R.E. DIETZ COMPANY

TO: CHIEF COUNSEL NHTSA

TITLE: NONE

ATTACHMT: ATTACHED TO LETTER DATED 10/01/79, FROM FRANK BERND -- NHTSA TO LEO BACHYNSKY; OPINION BOOK; STANDARD 108, A17

TEXT: Dear Sir:

Our company is presently developing a new product and is in need of a clarification concerning the legality of the proposed product as it pertains to FMVSS 108.

Briefly, the device is a bi-directional Emergency Vehicle Warning Lamp consisting of two 7-1/2 inch diameter lenses. The lenses contain a 5/8 inch wide band of reflex reflector around their periphery. The two lenses are locked to a mounting flange by a special locking feature and two screws. When mounted, the device will have one lens facing to the front of the vehicle and the other to the rear. The device is to be supplied in a variety of colors, red, yellow, blue, and can be used in either a steady or flashing state.

We manufacture a similar device less the reflex reflector area and previous sales data indicates the majority of the market for this type of device is for tow trucks and utility company vehicles.

We are aware of the fact that Emergency Warning Lamps are not regulated by FMVSS 108 or any other Federal standard, but rather our questions concern the reflex reflector area in the device.

The areas that need clarification with respect to our application are the following:

1. Paragraph S.4.1.3 of FMVSS 108 - "No additional lamp, reflective device or other motor vehicle equipment shall be installed that impairs the effectiveness of the equipment required by this standard."

Does this Paragraph S.4.1.3. restrict the use of the reflex reflector in our proposed device as imparing effectiveness of required equipment?

2. Do Tables 1-4 of FMVSS 108 "Required Equipment for Motor Vehicles" and "Locations of Required Equipment" restrict the use of a red reflex reflector facing the front and yellow reflex reflector facing the rear of the vehicle?

An early reply will be appreciated.

Enclosed is our blueprint of the subject device and an advertising poster showing exact application of the intended device.

Sincerely,

Enclosure (2)

ID: nht91-4.34

Open

DATE: July 1, 1991

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: John Mayeda -- Marketing and Sales Coordinator, GRE America, Inc.

TITLE: None

ATTACHMT: Attached to letter dated 6-4-87 from Erika Z. Jones to Robert J. Heath; Also attached to letter dated 9-21-89 from Stephen P. Wood to Jim Bowen; Also attached to letter dated 1-7-89 from Erika Z. Jones to Koji Tokunaga (Std. 101); Also attached to letter dated 5-6-91 from John Mayeda to the Department of Transportation, NHTSA (OCC 6034)

TEXT:

This responds to your letter asking whether there are any laws or regulations that govern car stereos. You asked this question in the context of a stereo system that you are considering developing. The stereo would include a built-in television monitor.

I note that your letter and an enclosed drawing are stamped "Proprietary Information." In a May 30, 1991 telephone conversation, Elizabeth Barbour of my staff advised you that all NHTSA interpretation letters are a matter of public record, and that all incoming requests are also made public unless confidential treatment is requested and granted. You indicated your understanding of this policy and stated that you did not wish to request that the materials you submitted be treated confidentially.

The National Highway Traffic Safety Administration does not have any safety standards specifically covering car stereos or television receivers. However, a car stereo or television receiver may include a source of illumination which is regulated by Standard No. 101, Controls and Displays. Further, the installation of a car stereo or television receiver could affect the compliance of a vehicle with a number of safety standards. I have enclosed copies of three letters which discuss these and a number of other issues relating to the installation of radios or television receivers in motor vehicles. They include a June 4, 1987 letter addressed to Pansonic, a January 7, 1988 letter addressed to Isuzu, and a September 21, 1989 letter addressed to Gulf Stream Coach.

I hope this information is helpful.

ID: nht89-1.23

Open

TYPE: INTERPRETATION-NHTSA

DATE: 02/21/89

FROM: T. CHIKADA -- MGR., AUTOMOTIVE LIGHTING, ENGINEERING CONTROL DEPT., STANLEY ELECTRIC CO., LTD.

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

TITLE: INSTALLATION OF DECORATIVE EXTRA LIGHTING DEVICES ON MOTORCYCLES, WHICH ARE NOT SPECIFIED IN FMVSS NO. 108

ATTACHMT: ATTACHED TO LETTER DATED 3-20-90 TO T. CHIKADA, STANLEY ELECTRIC CO., LTD., FROM STEPHEN P. WOOD, NHTSA; [A35; STD. 108]

TEXT: We have an idea of producing two decorative extra lighting devices which are not specified in FMVSS No. 108.

As shown in the attached sheet, these decorative devices will be installed on the rear face, and at the top of optional motorcycle rear trunks respectively. The distance between center of light source of device A and B is 290 mm.

The light source of device B is incandescent bulb, and that of device A is LED. Color of emitted light of both devices (A and B) is red. Both devices (A and B) are energized when tail lamp is on. And they (A and B) are so designed as to have the maximu m intensity less than that minimum intensity of tail lamp C. (It is a matter of course that the minimum and maximum intensities of tail lamp C satisfy the requirement of FMVSS No. 108.)

Please let us have your answers for the following questions.

Q.1 Is it permitted to equip a motorcycle with the above mentioned accessory lamps?

Q.2 If the answer to the above question is "YES",

1) is it acknowledged to use LED as the light source of device B?

2) should maximum intensity of each lamp (A or B) separately be less than the minimum intensity of tail lamp C? or should combined maximum intensity of both lamps (A and B) be less than the minimum intensity of tail lamp C?

We are looking forward to your advice.

(Graphics omitted)

ID: nht95-2.86

Open

TYPE: INTERPRETATION-NHTSA

DATE: May 18, 1995

FROM: Jim Burgess -- Engineering Manager, Independent Mobility Systems, Inc

TO: Walter Myers -- Chief Council, NHTSA

TITLE: NONE

ATTACHMT: ATTACHED TO 8/4/95 LETTER FROM JOHN WOMACK TO JIM BURGESS (A43; REDBOOK 2; STD. 206)

TEXT: Dear Mr. Meyers:

Per our conversation earlier today, I am writing to learn your interpretation of 49CFR, 571.206, S4, as it pertains to our vehicles.

As we discussed, for eight (8) years, Independent Mobility Systems, Inc., has been converting Chrysler minivans, and recently Ford minivans, into wheelchair accessible vehicles by lowering the floor and adding a wheelchair ramp in the passenger side rear sliding door area. We have crash tested these converted vehicles at OTRC in Ohio for FMVSS 571.208 Frontal Impact, and for FMVSS 571.301 Rear Impact and Side Impact, to gain certification.

In regard to 49CFR, 571.206, S4, our interpretation is that side doors on motor vehicles which are equipped with wheelchair lifts, and linked to an alarm system consisting of either a flashing visible signal located in the driver's compartment or an alar m audible to the driver which is activated when the door is open, need not conform to this standard, pertains to our converted vehicles. We believe the wheelchair ramp we employ serves the same function as a wheelchair lift, in that it provides those per sons in wheelchairs or access to the vehicle, and thus we do not have to conform to this standard.

Because we have had inquiries from customers on this issue, your written interpretation to our inquiry will be appreciated.

ENCLOSURE

June 16, 1995

Dear Mr. Meyers:

As per our telephone conversation this morning, I am sending the enclosed brochures on our current offerings. As I stated, we are working on converting the new 1996 Chrysler NS minivans. We are scheduled for crash testing this vehicle the latter part o f July and offer it for sale in mid-August.

If you have any further questions before ruling on our request of May 18, 1995, regarding interpretation of 49 CFR, 571.206, S4, please call me.

Sincerely,

INDEPENDENT MOBILITY SYSTEMS, INC.

Jim Burgess Engineer

Enclosure: RAMPVAN BROCHURE/PHOTOS OMITTED

ID: nht92-9.35

Open

DATE: January 29, 1992

FROM: J. Yoshimoto -- Manager, Technical Administration Dept., Koito Manufacturing Co., Ltd.

TO: James G. White -- Surface Group, Transport Canada

TITLE: Subject: CMVSS 108 "Lighting Equipment"; Reference: Canada Gazette Part II, Vol. 125, No. 26 dated December 18, 1991

ATTACHMT: Attached to letter dated 3/5/92 from Paul Jackson Rice to James G. White (A39; Std. 108)

TEXT:

Thank you for your kind consideration which you have always extended to us through SAE meeting.

We have studied the amended CMVSS 108 "Lighting Equipment" by Canada Gazette Part II Vol. 125, No. 26 dated December 18, 1991. And we would ask for your kind interpretation about "O" Mark on vertical/horizontal aim indicator of integral headlamp aiming device, specified in paragraph 108(28)(b)(ii)(A) and 108(28)(c)(ii)(A).

108(28)(b)(ii) a scale that has (A) a "O" mark that represents the vertical aim of zero degrees, ----------. 108(28)(c)(ii) a scale that has (A) a "O" mark that (I) presents the horizontal aim of zero-degrees ----------.

For these descriptions, it is unclear for us whether a mark of figure "O" be literally required for indicating zero degrees on vertical/horizontal aim indicator, or not.

In FMVSS 108 (U.S.), vertical/horizontal aim indicator of integral headlamp aiming device is required to have a zero mark, which does not necessarily mean a mark of figure "O", but may be just a reference mark. (Please refer to the attached copy of FMVSS 108 S7.7.5.2(a)(1) and (2).

Size of indicator is so small, that there is no space to add a figure "O" on it. Moreover, from the viewpoint of harmonization to FMVSS 108, CMVSS 108 should not require a figure "O" on the indicator, we think.

We would greatly appreciate if you would give us your kind interpretation to the above matter.

Thanking you for your kind and prompt reply in anticipation, we remain, With best regards.

ID: 15591.jeg

Open

Mr. Shintaro Nakatsuka
Vice President and General Manager
Mazda (North America), Inc.
1025 Connecticut Avenue, NW
Suite 910
Washington, DC 20036

Dear Mr. Nakatsuka:

This responds to your request for an interpretation of Standard No. 208's requirements for passenger air bag manual cut-off devices. You note in your letter that S4.5.4.3 of the standard requires a telltale on the instrument panel to notify vehicle occupants when the passenger air bag has been deactivated by use of the manual cutoff device that is permitted in certain vehicles under the provisions of S4.5.4. You also note that S4.5.4.3(d) specifies that the telltale "shall not be illuminated at any time when the passenger air bag is not deactivated." You state that it is your belief that this specific prohibition would not apply to the illumination of the telltale for a brief period during a bulb check when the vehicle is started, and ask us to advise whether this is correct. As discussed below, your understanding is correct.

While Standard No. 208 does not address the subject of bulb checks for cut-off device telltales, the general subject of bulb checks for telltales is addressed in other safety standards. S5.3.1 of Standard No. 101 specifies for most telltales that "(a) telltale shall not emit light except when identifying the malfunction or vehicle condition for whose indication it is designed or during a bulb check upon vehicle starting." Moreover S5.3.2 of Standard No. 105 requires a bulb check function for brake indicator lamps.

We agree with your view that the concept of a bulb check is well understood by vehicle owners and operators and therefore, if a bulb check function was to be incorporated in the telltale required by S4.5.4.3, there would be no danger of confusion and it could possibly enhance the reliability of the manual cut-off switch device permitted by S4.5.4. Given general industry practice in this area and the treatment in other Federal motor vehicle safety standards of bulb checks for telltales, we agree that the prohibition in S4.5.4.3(d) of Standard No. 208 should be interpreted as not applying to the illumination of the cut-off device telltale for a brief period during a bulb check when the vehicle is started.

I hope this information is helpful. If you have any further questions, please feel free to call Edward Glancy of my staff at (202) 366-2992.

Sincerely,
John Womack
Acting Chief Counsel
ref:208
d.10/20/97

1997

ID: nht91-7.37

Open

DATE: December 9, 1991

FROM: Hanno Westermann -- Hella KG Hueck & Co.; Olaf Schmidt -- Hella KG Hueck & Co.

TO: Richard L. van Iderstine -- NHTSA

TITLE: Definition of 2 or 4 Headlamp System

ATTACHMT: Attached to letter dated 3/5/92 from Paul Jackson Rice to Herrn. Westermann u. Schmidt (A39; Std. 108)

TEXT:

Since the great revision of FMVSS No. 108 by Docket 85-15, Notice 12 of February 8, 1990, we are missing a paragraph clarifying the definition of a 2 or 4 headlamp system respectively.

In the former version of 108, this definition was done under para. S4.1.1.36, but today there only remains figure 26, which explains the application of photometric requirements with respect to the bulb or bulb combination used.

We assume that no changes to the sense of 108 have been made for this matter so that our remarks could be added to FMVSS 108 by short term to avoid the current discrepancies between headlamp manufacturers and the test laboratories.

Attached you will find a sketch representing our understanding of the definition of a 2 or 4 lamp system, deriving from the former 108.

Many thanks for your endeavours in this and

A Merry Christmas and a Happy New Year.

Attachment

Drawings of Replaceable Bulb Headlamp Systems. (Graphics omitted)

ID: nht87-2.24

Open

TYPE: INTERPRETATION-NHTSA

DATE: 06/26/87

FROM: AUTHOR UNAVAILABLE; Erika Z. Jones; NHTSA

TO: The Honorable Bill Schuette

TITLE: FMVSS INTERPRETATION

TEXT:

The Honorable Bill Schuette U.S. House of Representatives P.O. BOX 631 Midland, MI 48640

Dear Mr. Schuette:

Thank you for your June 4, 1987, letter on behalf of your constituent, Mr. Dale Lighthill of Owosso. Mr. Lighthill owns a semi-trailer which he has converted into a travel home. He wishes to know whether there is any law which prohibits him from carrying persons in his travel trailer.

Our agency is responsible for promulgating safety standards for the manufacture and sale of new motor vehicles. We have no jurisdiction over the use of motor vehicles and thus have no regulation prohibiting Mr. Lighthill from carrying people in his trave l home trailer. However, many states have enacted provisions in their vehicle codes for occupying moving trailers. Some states prohibit persons from occupying a moving trailer or operating a motor vehicle which is towing an occupied trailer, and some per mit occupying a moving trailer only under certain circumstances. I am certain that the officials of the states your constituent plans to visit will be happy to provide information on their laws for transporting persons in moving trailers. In addition, Mr . Lighthill night find it helpful to contact the American Association of Motor Vehicle Administrators (AAMVA) for general information on state requirements. The AAMVA may be reached at: Suite 910, 1201 Connecticut Avenue, N.W., Washington, D.C., 20036. T elephone: (202) 296-1955.

Thank you for contacting our office. Please contact me if you or your constituent have any questions.

Sincerely,

Erika Z. Jones Chief Counsel

Erika Jones Chief Counsel NHTSA 400 7th Street, SW Room 5219 Washington, D.C. 20590

Dear Erika:

I am writing with a request from my constituent, Dale Lighthill, of Owosso, Michigan. Mr. Lighthill owns a semi-trailer which has been converted into a travel home. He would like to know if there are any laws prohibiting carrying someone in the trailer s ection of this travel home anywhere in the continental U.S.

I would appreciate it if you could research this question and advise me at my Midland District Office of your findings. Thank you very much for your time and attention to this matter.

Sincerely,

Bill Schuette Member of Congress

ID: nht76-4.5

Open

DATE: 01/07/76

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

TO: The Leithiser Company

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your November 14, 1975, question whether an air-braked trailer that carries three spools of electric power line and is designed to pay out and tension the three lines over towers would be required to comply with Standard No. 121, Air Brake Systems.

Section S3. (Application) states in part that ". . . the standard does not apply to any trailer whose unloaded vehicle weight is not less than 95 percent of GVWR [gross vehicle weight rating] . . ." It appears from your description that the trailer in question does not have either a passenger-carrying capacity or a rated cargo load. The unloaded vehicle weight would be equal to the GVWR and the trailer would be exculded from the requirements of the air brake standard.

YOURS TRULY,

The Leithiser Company

November 14, 1975

Administrator, Dept. of Transportation National Highway Safety Administration

Reference: Standard No. 121, Air Brake Systems, 49 CFR 571.121 Tensioner - Tri-Axle Mounted

On March 15, 1974 we submitted a quotation to the Cleveland Electric Illuminating Co., Cleveland, Ohio covering the construction of a piece of special machinery for tensioning electric power lines. On April 10, 1974 we received a purchase order for the equipment.

We are enclosing a line sketch of the referenced device. The machine is mounted on a tri-axle suspension because the gross weight of 34,000 lbs. exceeds by 2,000 lbs. the legal limit in Ohio for a tandem axle.

Due to recent problems in the delivery of components, this machine will not be completed until March or April of 1976. The addition of "121" equipment to this device, particularly in view of the three axles, would increase the cost to our customer approximately $ 4,000,00.

We feel that because this is a specialized piece of equipment that the econimic burden of acquiring certification and the increase in cost to our customer, should relieve us of the necessity for installing the "121" appliances. May we have a ruling in this matter as soon as possible?

George L. Leithiser, Pres.

(Graphics omitted)

The LEITHISER Company York, Fa

THREE REEL PAYOFF TRA. DCALO 1/32 "DWO MC. DATE 11/10/75 DWN. WY M. KLINK

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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