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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 1241 - 1250 of 2914
Interpretations Date

ID: nht88-2.67

Open

TYPE: INTERPRETATION-NHTSA

DATE: JULY 11, 1988

FROM: WILLIAM SHAPIRO -- MGR., REGULATIONS AND COMPLIANCE, VOLVO CARS OF NORTH AMERICA TO: ERIKA Z. JONES -- CHIEF COUNSEL, NHTSA

TITLE: FEDERAL MOTOR VEHICLE SAFETY STANDARD NUMBER 210; SEAT BELT ASSEMBLY ANCHORAGES - REQUEST FOR INTERPRETATION

ATTACHMT: ATTACHED TO LETTER DATED 4-16-90 TO WILLIAM SHAPIRO FROM STEPHEN P. WOOD; (A35; STD. 210). ALSO ATTACHED TO LETTER DATED 4-18-89 TO ERIKA Z. JONES FROM WILLIAM SHAPIRO; (OCC-3422). TEXT:

Section 4.3.2 of FMVSS 210 sets forth the location requirements for the upper torso portion of Type 2 seat belt assemblies. This section requires the seat belt anchorage for the upper end of the upper torso restraint to be located within the acceptable r ange shown in Figure 1 of FMVSS 210.

Volvo is currently designing a Type 2 seat belt assembly that has its upper torso anchorage point located in the acceptable range as defined in Figure1. The function of the seat belt and all strength requirements specified in FMVSS 210 are met using thi s anchorage point.

Volvo believes that an extra set of hardware at the upper torso anchorage would increase the stability of the mounting. The location of this extra set of hardware would fall outside the acceptable range as specified in Figure 1.

Volvo believes that a correct interpretation of FMVSS 210, with respect to the extra set of hardware for the upper torso anchorage, would be that it is acceptable for it to fall outside the range as specified in Figure 1, because the extra set of hardwar e is not required for the seat belt assembly to comply with the strength requirements as specified in FMVSS 210. Please confirm this for us.

Thank you for your attention to this matter. If you require any additional information, please feel free to contact me.

ID: nht92-7.34

Open

DATE: April 21, 1992

FROM: Al Twyford

TO: Associate Administrator for Safety, Federal Highway Administration

TITLE: None

ATTACHMT: Attached to letter dated 5/14/92 from Paul J. Rice to Al Twyford (A39; Std. 108)

TEXT:

I would like to voice a complaint about some makes of new cars that have two sets of headlights (4), which operate at the same time. When approaching these vehicles at night, going in the opposite direction, it has the same effect as a car approaching my vehicle with the high beam headlights on. I have had conversations with the California Highway Patrol and Department of Motor Vehicles, and they claim that these headlamps are approved for auto manufacturers by your department. They claim they can do nothing about the problem, without a change on the matter by your agency.

If you are committed to Highway Safety, why would you approve these headlamps for automobiles? Night driving is bad enough, without adding more vehicles to the highway with these extra bright lights which have the effect of highbeam brightness. I would like to ask that you re-examine your approval of these extra headlamps, and do some further testing under night time driving conditions. I personally have responded to these automobiles with the four lights with a dose of my highbeams to get these drivers to turn off the extra set of headlights. This doesn't seem to work as they either don't realize what they are doing to oncoming traffic, or can't turn off the lower set of lights. I might add that from the rear of my vehicle, it's the same problem; the approaching vehicle has the effect on me of highbeam lights in my rear view mirror and side view mirror.

I would appreciate some feedback on this problem, and what you propose to do about it. If you do nothing, I plan to take this matter up with Congressmen and U.S. Senators.

Thank you.

ID: volvo.crs

Open

Mr. William Shapiro
Director, Regulatory Compliance
and Environmental Affairs
Volvo Cars of North America, Inc.
Volvo Drive
Rockleigh, NJ 07647-0913

Dear Mr. Shapiro:

This responds to your letter of March 11, 1998, requesting the National Highway Traffic Safety Administration (NHTSA) to approve an alternate location for placement of the certification label on vehicles within a new car line, currently designated as "P23," that Volvo plans to introduce into North America beginning in model year 1999. Although you requested confidential treatment of the information contained in the March 11, 1998 letter and in its enclosure, you subsequently withdrew that request. Accordingly, this letter makes reference to certain of that information.

NHTSA's regulations at 49 CFR 567.4(c) prescribe specific locations for the installation of vehicle certification labels, and provide that if none of those locations are practicable, the manufacturer may suggest an alternate location for the agency's approval. As identified in your letter, and in an accompanying drawing, the alternate location for which you have requested approval is on the vehicle's B-pillar, facing the door opening of the rear door on the driver's side. In a subsequent letter, dated March 23, 1998, you state that it is not possible for the certification label to be placed in any of the locations specified in 49 CFR 567.4(c) owing to the size of the label, the corresponding surface geometry of each of those locations, and adhesion difficulties owing to the surface properties at some of those locations.

In specifying locations for the placement of vehicle certification labels, NHTSA's objective is to ensure that those labels may be easily read. The location that you have proposed for vehicles in the P23 new car line would meet this objective. NHTSA therefore approves your request.

If you have any further questions regarding vehicle certification requirements, feel free to contact Coleman Sachs of my staff at 202-366-5238.

Sincerely,
John Womack
Acting Chief Counsel
Ref:567
d.4/29/98

1998

ID: ward.ztv

Open

    L. Taylor Ward, III, Esq.
    Vice President & General Counsel
    Southeast Toyota Distributors, LLC
    100 N.W. 12th Avenue
    Deerfield Beach, FL 33442

    Dear Mr. Ward:

    This is in reply to your letter of February 7, 2003, relating to motor vehicle distributors who add accessory equipment to new vehicles before they are sold. You are concerned specifically about accessory equipment produced by someone other than the manufacturer of the vehicle. This equipment includes "audio systems, tires, wheels, cruise control, trailer hitches, luggage racks, running boards, spoilers, truck bed liners, and convenience equipment." You are unclear "where [distributors] fit under the [TREAD] Acts definitions, and what reports are required of them for the non-Toyota, domestic accessories they install." You believe that distributors of Toyota cars and trucks "should logically only be responsible for reporting information on non-Toyota parts and accessories they install."

    The early warning reporting (EWR) obligations of the TREAD Act (Subpart C of 49 CFR Part 579) apply to manufacturers of motor vehicles and motor vehicle equipment. They do not apply to distributors and dealers who only add accessory equipment to a vehicle before its first sale, in the nature of the equipment you listed: "audio systems, tires, wheels, cruise control, trailer hitches, luggage racks, running boards, spoilers, truck bed liners, and convenience equipment." The fact that the accessory equipment may not be factory authorized is irrelevant to this conclusion.

    The manufacturer is responsible under EWR for reporting certain information it receives from distributors and dealers in the ordinary course of business, such as the number of field reports and warranty claims. But there is no independent obligation under EWR for distributors and dealers to report this, or any other information, to NHTSA under the EWR regulations.

    If you have any questions, you may call Taylor Vinson of this Office (202-366-5263).

    Sincerely,

    Jacqueline Glassman
    Chief Counsel

    ref:579
    d.5/16/03

2003

ID: 10104

Open

Mr. Keith E. Smith
Piper & Marbury
2 Penn Center Plaza, Suite 1500
Philadelphia, PA 19102-1715

Dear Mr. Smith:

This responds to your letter asking whether the National Highway Traffic Safety Administration (NHTSA) considers automotive and motorcycle braking systems to be "safety devices." As explained below, the agency considers such systems to be items of motor vehicle equipment.

Please note that neither the National Traffic and Motor Vehicle Safety Act (formerly at 15 U.S.C. 1381 et seq. and recently codified in Title 49 of the U.S. Code) nor the agency's regulations in Title 49 of the Code of Federal Regulations use the phrase "safety device." Rather, the statute refers to "motor vehicles" and "motor vehicle equipment." Specifically, motor vehicle equipment is defined, in relevant part, as

any system, part, or component of a motor vehicle as originally manufactured or any similar part or component manufactured or sold for replacement or improvement of such system, part, or component or as any accessory, or addition to the motor vehicle ...

Under this definition, NHTSA would consider an automotive or motorcycle braking system to be an item of motor vehicle equipment.

Please note that the Federal motor vehicle safety standards are issued to meet the need for safety. For example, the purpose of Standard No. 105, which regulates hydraulic brake systems of passenger cars and other specified vehicles, is "to insure safe braking performance under normal and emergency conditions." See S2 of Standard No. 105. Similarly, the purpose of Standard No. 122, which regulates motorcycle brake systems, is "to insure safe motorcycle braking performance under normal and emergency conditions." See S2 of Standard No. 122.

I hope this information is helpful. If you have any further questions about NHTSA's safety standards, please feel free to contact Marvin Shaw of my staff at this address or by telephone at (202) 366-2992.

Sincerely,

John Womack Acting Chief Counsel

ref:VSA d:8/18/94

1994

ID: 18033.ztv

Open

Mr. Edward F. Dugan
President
Soda Fountain
FAX 908-322-3026

Dear Mr. Dugan:

This is in reply to your letter of May 14, 1998, to the New York Regional Office of this agency, with respect to a lighting device that you wish to offer to funeral directors. This device is a battery operated lamp, 3 inches in diameter, intended to be attached by a magnet or suction cup to the roofs of cars in funeral processions. The lamp, which emits a white color, flashes, with the intent of assisting drivers in the procession to stay together. You also note your belief that, with the advent of daytime running lamps, headlamps alone "are no longer a sufficient identifier of a funeral procession." You have asked if we have any objection to the use of these lamps.

The use of these lamps would not violate any Federal statute or regulation. They are subject to the laws of the State or municipality in which they will be used. Some jurisdictions may prohibit the use of flashing lights except on police or emergency vehicles. However, we are not conversant with local laws and are not able to advise you about them.

Because our interpretations are a matter of public record, I would like to explain briefly, without legal citations, how we reached our conclusion that the use of these lamps is not prohibited under Federal law. A flashing white lamp cannot be installed on a new motor vehicle, before its first sale, because all lamps must be steady burning, except for turn and hazard warning signals, school bus warning lamps, and headlamps that flash for signaling purposes. After the first sale of a vehicle, the lamp could not be attached by a manufacturer, dealer, distributor, or motor vehicle repair business because that would make inoperative the Federal lighting standard that applied to the vehicle when it was new. But this prohibition covers only the entities named, and installation of the flashing lamp by a person other than the entities named is not prohibited. That is to say, an employee of a funeral home or the owner of a vehicle in the procession can install the lamp without violating Federal law.

Sincerely,
Frank Seales, Jr.
Chief Counsel
ref:108
d.6/24/98

1998

ID: nht76-1.27

Open

DATE: 03/08/76

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

TO: Michelin Tire Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your letter of January 27, 1976, concerning the rim listing requirements of Federal Motor Vehicle Safety Standards No. 109 and 110.

You wish to designate the 15x5.5JJ rim as permissible for use with tire sizes 225-15 and 230-15. You have requested confirmation of your interpretation that you need merely list the rim in a document that is furnished to your dealers, to any person on request, and in duplicate to the Tire Division of the NHTSA. Your interpretation is correct. Please note, however, that this listing must include dimensional specifications and a diagram of the rim, unless each of the association publications referred to in S4.4.1(b) of Standard No. 109 in which the rim is listed already contains such specifications and diagram.

We hope that you will also ensure that this tire-rim combination is listed in one of those publications as soon as is possible.

MICHELIN TIRE CORPORATION Technical Group

JANUARY 27, 1976

Office of the Chief Counsel National Highway Traffic Administration Department of Transportation

Re: FMVSS 109 - New Pneumatic Tires for Passenger Cars FMVSS 110 - Tire Selection and Rims

We are writing to confirm our interpretation of paragraph S.4.4.1 of FMVSS 110 and paragraph S.3 and S.4.4.1 of FMVSS 109.

It is our understanding that in order to add an additional permissible rim width for a tire which is already listed in the tables of FMVSS 109, we need merely include it in a document (such as our Data Book or Technical Bulletin) which is furnished to our dealers and to any person upon request, and in duplicate to the Tire Division of NHTSA.

It is our immediate need to add the 15x5.5JJ rim as a permissible fitment for tire sizes 225-15 and 230-15.

Your prompt reply would be appreciated. Thank you.

John B. White Engineering Manager Technical Information Dept.

ID: nht90-3.69

Open

TYPE: Interpretation-NHTSA

DATE: August 27, 1990

FROM: William Shapiro -- Manager, Regulations and Compliance, Volvo Cars of North America

TO: Paul J. Rice -- Chief Counsel, NHTSA

TITLE: Re FMVSS 210, Request for Interpretation

ATTACHMT: Attached to letter dated 11-9-90 from P.J. Rice to W. Shapiro (A36; Std. 210)

TEXT:

Section 4.3.2 of FMVSS 210 sets forth the anchorage location requirements for the upper torso portion of type 2 seat belt assemblies. Section 3 defines seat belt anchorage as the provision for transferring seat belt assembly loads to the vehicle structu re.

Volvo is currently designing a type 2 seat belt assembly for the rear seating positions of a proposed vehicle. The retractor is mounted within the seat back, in order to improve the seat belt geometry, to increase the comfort of the occupants, and to al low movement of the seat back. The retractor is located outside of the zone specified in Section 4.3.2, figure 1. However, the shoulder portion of the belt travels from the retractor through a device we are calling a "belt anchor", which is the functio nal equivalent of a d-ring. Kindly see the attached drawings, Appendices A & B, for clarity.

The belt anchor is located within the specified zone. Its function is to transfer the seat belt assembly load to the vehicle structure, and to determine the angle the belt crosses the vehicle occupant.

This belt anchor complies with the force requirements of the standard. Please see the attached drawings, Appendices C, D & E for the forces in the proposed design. For comparison, Appendices F & G show the forces on a current vehicle.

Volvo believes that a correct interpretation of FMVSS 210 in this case is that the belt anchor is the upper anchorage point for this seat belt system. Please confirm this for us.

Our engineers must finalize the design by this Fall. As such, we respectfully request that you reply by November 1, 1990.

Thank you for your attention to this matter. Should you have any questions, kindly contact Linda Gronlund of my office at 201-767-4815.

ID: nht89-2.19

Open

TYPE: INTERPRETATION-NHTSA

DATE: 06/22/89

FROM: WOLFRED FREEMAN -- FREEMAN AND COMPANY

TO: ADMINISTRATOR NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION

TITLE: NONE

ATTACHMT: ATTACHED TO LETTER DATED 11/06/89 FROM STEPHEN P. WOOD -- NHTSA TO WOLFRED FREEMAN; REDBOOK A34; STANDARD 108

TEXT: Dear General Curry,

I hereby petition your bureau for permission to produce a color coded (Green-Amber-Red) rear light device for all types of motor vehicles. This type of signal would provide information to the driver of the following vehicle as to what actions is taking place. Just as one seeing a "white back up light" knows that the driver intent is to back up, whether the vehicle is moving or not. With my proposed device one would immediately know what the drivers intentions were. If the driver had their foot on the gas the light would be Green, as soon as the foot was removed from the throttle, the light would show Amber alerting the following driver that the driver in front had removed their foot from the gas and was costing or about to make a move either to the gas or the brake. The present system of Red light intensity provides no information as to driver intent.

I think the variable glow Red has a tendency to mesmerize one over a period of time and should be improved for traffic safety.

It is my understanding that research has already been done by your Bureau on human factor reaction time to my proposed signal as opposed to light intensity differential systems now in use. It is also my understanding that this research favored my type o f system.

We have designed a workable auxiliary system that can be adopted to cars and trucks now on the road. But before we go any further we want to be sure that we will not be beating our heads against a bureaucracy wall.

I think your review of my request will disclose enough research and development to allow for a speedy approval of my request.

Awaiting your reply, I remain, Sincerely.

ID: 20949.ztv

Open

Mr. William T. Smith
110 Spear Street
Metuchen, NJ 08840-2126

Dear Mr. Smith:

This is in reply to your letter of November 3, 1999, to the agency on daytime running lamps (DRLs). It was your impression that all 2000 model year passenger cars were required to have DRLs, and you ask if you may have them installed on your new Mercury without voiding the vehicle's warranty.

Federal Motor Vehicle Safety Standard No. 108, Lamps, Reflective Devices and Associated Equipment, requires motor vehicles to be manufactured in compliance with its specifications. Under Standard No. 108, DRLs are not a required lighting system, but the standard permits manufacturers to install a DRL system if they wish. If the manufacturer exercises this option, the DRL system must comply with the requirements specified in Standard No. 108.

Ford Motor Company, the manufacturer of your new car, chose not to equip it with a DRL system. This agency does not regulate or review vehicle warranties. It is possible that certain aspects of your vehicle warranty could be voided by altering the vehicle wiring were you to have a DRL system installed by a person not authorized by Ford. We recommend that you contact Ford's Zone Office for its opinion.

Your local mechanic is allowed to install a DRL system on your car under Federal law, provided that the mechanic does not make inoperative any element of design or device installed in accordance with one of the Federal motor vehicle safety standards. We interpret this to mean that an aftermarket DRL system is permissible as long as it does not interfere with the performance of other lighting equipment and conforms to the specifications of Standard No. 108 for an original equipment DRL system. Our greatest concern is that an aftermarket DRL system not exceed the maximum luminous intensity limits. For example, a lower beam headlamp may be wired to operate as a DRL at full voltage, but an upper beam headlamp may not.

If you have further questions, you may call Taylor Vinson of this Office (202-366-5263).

Sincerely,
Frank Seales, Jr.
Chief Counsel
ref:108
d.4/27/00

2000

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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