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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 931 - 940 of 2067
Interpretations Date

ID: nht68-2.3

Open

DATE: 06/27/68

FROM: AUTHOR UNAVAILABLE; David A. Fay; NHTSA

TO: Department of Education

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your letter of June 4, 1968, to Mr. George C. Nield, concerning the State Board of Education's requirement for school bus warning signal lamps.

The warning signal system as described in your letter does not meet the requirements of Federal Motor Vehicle Safety Standard No. 108, effective January 1, 1969. A copy of this Standard is enclosed for your reference. A minimum of four red signal lamps is required and they shall be designed to conform to SAE Standard J887, July, 1964, a copy of which is also enclosed. Four additional amber lamps are permitted. The red and amber system and the red only system shall be installed in accordance with paragraph S3.1.3.2 and S3.1.3.3, respectively, of Standard No. 108.

ID: 571.108--Supplement beam--Boykin--16-0884

Open

Mr. Marcus Boykin

B-G Innovative Safety Systems, LLC

79 Pasture Road

Lexington, TN 38351

Dear Mr. Boykin:

This responds to your letter asking about the application of Federal Motor Vehicle Safety Standard (FMVSS) No. 108, “Lamps, reflective devices, and associated equipment,” to a lighting system your company has developed.  In your letter and phone conversation with John Piazza of my staff, you describe your product as “an auxiliary vehicle lamp operating system” for use both as original equipment (OE) and as aftermarket equipment.

You state that your product, which adapts to the existing headlight wiring harness, provides a supplemental lower beam from the existing upper beam when the lower beam fails.  We understand that, when the lower beam is not in a failed state, the headlight system, controls, and telltales function normally.  If the lower beam is selected and has failed or does fail, your system provides a supplemental lower beam from the existing upper beam.  You state that the lighting on the converted upper beam is “diffused down to the same output illumination as” the lower beam.  If the upper beam is selected, the upper beam will continue to function normally. 

We further understand that, with respect to the OE version of your product, you contemplate a dashboard warning to warn the driver that the normal lower beam is not functioning.  In the aftermarket version of your product, once the vehicle’s lower beam has failed and your device is providing a supplemental lower beam, every time the engine is started the headlights will flash three times to warn the driver that the original equipment lower beam is not operating and that your device is providing a supplemental lower beam.  You state that you are seeking “interpretation and approval” of your device.

As we explain below, while NHTSA does not provide approvals of motor vehicles or motor vehicle equipment and does not make compliance determinations outside of an agency compliance proceeding, we are able to provide you with our interpretation of how NHTSA’s statute and regulations would apply to your product as you have described it to us.  We believe that your product would be considered supplemental lighting.  As such, it may be installed as original equipment as long as it does not impair the effectiveness of any required lighting.  If your product is offered as aftermarket equipment, it would not be directly subject to FMVSS No. 108 but would be subject to the Safety Act’s make inoperative prohibition.

Background

The National Highway Traffic Safety Administration (NHTSA) is authorized by the National Traffic and Motor Vehicle Safety Act (Safety Act), 49 U.S.C. Chapter 301, to issue Federal motor vehicle safety standards that set performance requirements for new motor vehicles and new items of motor vehicle equipment.  NHTSA does not provide approvals of motor vehicles or motor vehicle equipment and does not make determinations as to whether a product conforms to the relevant FMVSS outside of an agency compliance proceeding.  Instead, the Safety Act requires manufacturers to self-certify that their products conform to all applicable FMVSSs.  Manufacturers must also ensure that their products are free of safety-related defects.

This letter provides you with our interpretation of how the statute and regulations administered by NHTSA would apply to your product as you have described it to us, based on our understanding of the information provided.  This is not an “approval” of your product.

Vehicle lighting sold as OE is regulated under FMVSS No. 108.  (All references in this letter are to subsections of FMVSS No. 108 unless otherwise noted.).  FMVSS No. 108 requires vehicles to be equipped with certain types of lamps (known as “required” lamps), which must meet very specific and detailed performance standards.[1]  All other lamps are considered “supplemental” lamps.[2]  Unlike OE required lamps, OE supplemental lamps are not required to meet any specific performance requirements.  However, they are required to comply with certain generally-applicable provisions of FMVSS No. 108.  One of these provisions is set forth in S6.2.1, which states: “No additional lamp, reflective device, or other motor vehicle equipment is permitted to be installed that impairs the effectiveness of lighting equipment required by this standard.”

Both OE and aftermarket vehicle lighting are subject to the Safety Act’s “make inoperative” prohibition (49 U.S.C. § 30122), which prohibits a manufacturer, distributor, dealer, rental company, or motor vehicle repair business from knowingly making inoperative any part of a device or element of design installed on or in a motor vehicle or motor vehicle equipment in compliance with an applicable FMVSS.  While this “make inoperative” prohibition does not apply to individual vehicle owners, NHTSA encourages vehicle owners not to remove or otherwise tamper with vehicle safety equipment.  Also, any modifications made by a vehicle owner would have to comply with applicable state law. 

Discussion

FMVSS No. 108 requires vehicles to be equipped with one of several permissible headlighting systems.  Headlighting systems are comprised of headlamps and associated hardware.  The purpose of headlighting is primarily to provide forward illumination.[3] 

The threshold issue presented by your request is whether your product is part of the required headlighting system, and thus subject to FMVSS No. 108’s requirements applicable to headlighting systems or, instead, supplemental lighting that is regulated by FMVSS No. 108’s impairment provision.   

In determining whether lighting equipment that provides forward illumination is part of the required headlighting system or, instead, supplemental lighting, NHTSA looks at several factors.  These include: (1) where the lamp directs its light; (2) whether it uses a headlamp replaceable light source to emit a beam that provides significantly more light flux than supplemental cornering lamps or fog lamps; (3) whether the lamp is intended to be used regularly, or is limited to more narrow driving conditions and situations; (4) whether the vehicle’s complete lighting system, not including the lamp in question, would include all of the forward lighting equipment required by FMVSS No. 108;  (5) whether there is a manual on/off switch; and (6) whether the lighting feature is one that activates only upon the failure of an element of the required headlighting system and acts as a temporary backup of that lighting element.[4] 

The last of these factors is most relevant to your product.  Prior agency interpretations have found that a lighting feature that activates an upper beam light source when the lower beam fails or a lower beam headlamp upon the failure of an upper beam headlamp is supplemental lighting.[5]  The system you describe activates a back-up beam only upon the failure of the required lower beam.  Accordingly, we believe it is supplemental lighting. 

Since you contemplate selling your supplemental lighting device as original and/or aftermarket equipment, we will consider the requirements affecting each of these.

Supplemental lighting installed as original equipment

Supplemental lighting installed as OE (i.e. before sale to first purchaser other than for resale) is permitted if the lighting does not impair the effectiveness of any lighting equipment required by FMVSS No. 108 (S6.2.1).  If you are the manufacturer of original lighting equipment required by FMVSS No. 108, but not the manufacturer of the vehicle on which it is installed, the vehicle manufacturer, and not you, has the legal responsibility under the Safety Act to certify that the vehicle complies with FMVSS No. 108 and all other applicable FMVSSs.  Accordingly, the vehicle manufacturer must certify that supplemental lighting installed as OE complies with S6.2.1.  Effectiveness may be impaired if, among other things, the device creates confusion with the signal sent by another lamp, or functionally interferes with it, or modifies its candlepower to either below the minima or above the maxima permitted by the standard.[6] 

Table XIX has specific photometry requirements (maxima and minima) for lower beams.  Activation of an upper beam light source when a lower beam source fails raises considerations of glare.  The lower beam maxima are meant to ensure that other roadway users are not glared.  If your device produces a supplemental beam that exceeds the lower beam photometric maxima, we would consider that to impair the effectiveness of the headlighting system.  Accordingly, your device needs to modify the upper beam to ensure that the lower beam photometric maxima are not exceeded. [7]  Because your device is supplemental lighting, it would not be required to provide sufficient illumination to meet or exceed the photometric minima required for a lower beam headlamp.  However, we note that by reducing the output illumination of the upper beam to that of the lower beam, the reduced upper beam would provide only a limited amount of illumination that may not be sufficient to usefully illuminate the road. 

For your information, we also point out below several other requirements of which you should be aware in designing and manufacturing your product.  (Note that it is the responsibility of manufacturers, and not NHTSA, to identity all FMVSSs applicable to their products and certify the compliance of their products with the standards.)

 

  • Your product must not interfere with the activation and operation of the upper beam.    
  •  It may not impair the effectiveness of the upper beam headlamp indicator required by S9.5.  When your device is providing a supplemental lower beam, it should do so in a way that the upper beam indicator is not activated.  Also, when the driver (or vehicle, if it has a semiautomatic headlamp beam switching device, or automatic headlights) has activated the upper beams, the upper beams must be activated and the upper beam indicator must be activated.  
  • S9.4 requires that “the lower and upper beams must not be energized simultaneously except momentarily for temporary signaling purposes or during switching between beams.” 
  • The headlamps must be steady burning, except that they may be flashed for signaling purposes.[8]  We would not consider your system’s momentary flashing function as violating this requirement because it is similar to a signaling function and would not be likely to confuse other motorists because it only flashes upon start-up.  
  • The device generally should not function in such a way that it would be likely to confuse other motorists (for example, it should not mask the ability of other drivers to perceive the front turn signal).
  • If a telltale or control is offered as original equipment, it must comply with any relevant requirements in FMVSS No. 101, “Controls and displays.”

 

We wish to point out that Table I-a requires that “[t]he wiring harness or connector assembly of each headlighting system must be designed so that only those light sources intended for meeting lower beam photometrics are energized when the beam selector switch is in the lower beam position[.]”  Although it may appear that a device such as yours might not meet this requirement, NHTSA has interpreted the requirement otherwise. 

This issue arises if the lower beam is activated (with the beam selector switch in the lower beam position) and then fails, after which a system (such as yours) activates a modified upper beam as a backup lower beam.  If the backup lower beam utilizes upper beam light sources that are not normally used for meeting lower beam photometrics, the backup lower beam might be viewed as violating this requirement.[9]  However, prior interpretations have concluded that this Table I-a requirement does not apply to a failure condition in which a supplemental beam supplements a failed lower or upper beam, assuming the supplemental light does not otherwise impair the effectiveness of any required lighting.[10]  Applying that line of reasoning, we believe that your system would not create a noncompliance with the Table I-a requirement.

Supplemental lighting offered and installed as aftermarket equipment

Supplemental lighting offered as aftermarket equipment (accessory lighting) is not directly subject to FMVSS No. 108, which applies only to original equipment and lighting equipment manufactured to replace original lighting equipment required by FMVSS No. 108.  Section 30122 of the Safety Act, however, prohibits a manufacturer, distributor, dealer, rental company, or motor vehicle repair business from knowingly making inoperative, in whole or in part original required lighting equipment.  In applying the make inoperative prohibition to accessory lighting we typically ask whether the accessory lighting would impair the effectiveness of any required lighting.  Generally, if an item of accessory lighting would not be permitted as original equipment, commercial entities will not be permitted to install the lighting as an aftermarket accessory for a vehicle in use.  Thus, the make inoperative analysis is generally the same as the impairment analysis we applied above in the context of supplemental lighting installed as original equipment.  We observe that, due to varying headlamp designs throughout the vehicle fleet, there may be potential compatibility issues with the product you describe and certain vehicles.  In addition, manufacturers of aftermarket lighting accessories are subject to the Safety Act’s defect notification and remedy requirements discussed above.    

We also note that manufacturers of equipment to which an FMVSS applies must meet the manufacturer identification requirements set out in 49 CFR Part 566.  For these and other requirements, you may consult NHTSA’s New Manufacturers Handbook, available at https://www.nhtsa.gov/sites/nhtsa.dot.gov/files/manufacturer_information_march2014.pdf.

If you have any further questions, please contact John Piazza at (202) 366-2992.

Sincerely,

Jonathan Morrison

Chief Counsel

Dated: 5/17/19

Ref: FMVSS No. 108

[1] The standard’s performance requirements also apply to lamps that are “for replacement of like equipment on vehicles to which this standard applies.”  On a related matter, we note that you state that “drivers with a failed light are out of compliance.”  This is incorrect, as FMVSS No. 108 does not regulate lighting in use.  Therefore, if a headlamp fails in operation, the vehicle is not “out of compliance” with the Federal standard (state laws may apply to in-use performance).

[2] NHTSA also uses the term “auxiliary” lamps.

[3] S4 (“Headlamp means a lighting device providing an upper and/or a lower beam used for providing illumination forward of the vehicle.”) (Formatting in original.)

[4] Letter to [Redacted] (Jan. 21, 2004) ((1)-(5)), available at https://isearch.nhtsa.gov/files/swivelinglamp.3.html (last accessed June 20, 2018); letter to L. W. Camp, Ford Motor Company (July 15, 1998) ((6)), available at https://isearch.nhtsa.gov/files/18080.ztv.html (last accessed June 20, 2018). 

[5] Letter to L. W. Camp, supra (lower beam backing up upper beam); letter to Ian Goldstein, Safe Passage Technologies (July 21, 1998) (upper beam backing up lower beam), available at https://isearch.nhtsa.gov/files/18164.ztv.html.

[6] See, e.g., letter to Byung M. Soh, Target Marketing Systems, Inc. (Sept. 13, 1988), available at https://isearch.nhtsa.gov/gm/88/nht88-3.100.html (last accessed June 20, 2018).

[7] Letter to Ian Goldstein, supra (“Because headlamps are primarily operated on the lower beam, activation of an upper beam light source when a lower beam source fails raises considerations of glare . . . the upper beam in this instance ideally should be activated at a markedly reduced intensity such that it does not impair the effectiveness of required lighting devices [S6.2.1], or, more specifically, that, as a lower beam substitute[] it does not compromise turn signal visibility.”)

[8] Table I-a.

[9] Whether this would occur depends on the design of that particular headlighting system.  For example, this would not be the case if the headlighting system used the same light sources for both the lower and the upper beams.

[10] Letter to L. W. Camp, supra (lower beam supplementing failed upper beam).  See also letter to Ian Goldstein, supra (modified upper beam supplementing failed lower

2019

ID: nht90-4.26

Open

TYPE: Interpretation-NHTSA

DATE: September 28, 1990

FROM: Takahiro Maeda -- Assistant to the Vice President, Engineering Divison, Yamaha Motor Corporation, U.S.A.; Signature by Michael Schmitt

TO: Office of Chief Counsel, NHTSA

TITLE: Re FMVSS 108

ATTACHMT: Attached to letter dated 12-7-90 to T. Maeda from P.J. Rice (A36; Std. 108)

TEXT:

The purpose of this correspondence is to obtain your interpretation of minimum "edge to edge" separation between the tail/stop lamp and turn signals pursuant to FMVSS 108 Table IV.

Tail/stop lamp design may feature a housing whereby the bulb reflector subassembly does not extend outward to the edge of the entire assembly. Can "edge to edge" be construed as the edge of the bulb reflector or is it necessarily the outer edge of the en tire tail/stop lamp assembly. Please refer to the attached illustration.

We thank you for your insight into this question.

Attached illustration. (Graphics omitted)

ID: nht94-8.30

Open

DATE: February 7, 1994

FROM: Martin M. Sackoff, Ph.D. -- Executive Director Of Laboratories, International Testing Laboratories

TO: Office of Chief Counsil -- NHTSA

TITLE: None

ATTACHMT: Attached To Letter Dated 5/12/94 From John Womack To Martin Sackoff (A42; Std. 109)

TEXT: Gentlemen:

The subject of this request is in reference with Motor Vehicle Safety Standard No. 109 - New Pneumatic Tires - Passenger Cars.

The specific question is with reference to S4.2.2.4 Tire Strength, which states "S4.2.2.4 Tire Strength. Each tire shall meet the requirements for minimum breaking energy specified in Table 1 when tested in accordance with S5.3".

I shall very much appreciate receiving a reply concerning the definition or interpretation of the term "breaking" of the tire. Does this mean a blowout of the tire, or simply the breaking of the tire caused by forcing the steel plunger into the tread?

Thank you.

Sincerely,

ID: nht93-7.14

Open

DATE: October 7, 1993

FROM: John Womack -- Acting Chief Counsel, NHTSA

TO: Erika Z. Jones -- Esq., Mayer, Brown & Platt

TITLE: None

ATTACHMT: Attached to letter dated 8/17/93 from Erika Jones to John Womack (OCC-9017)

TEXT:

This responds to your request for an interpretation of Federal Motor Vehicle Safety Standard No. 213, Child restraint systems. S5.2.3.2(b) of Standard No. 213 specifies a minimum thickness for materials of a certain compression-deflection resistance. You ask whether more than one piece of material may be used to meet the thickness requirement.

The answer is yes. S5.2.3.2(b) does not require the material to be of a single piece, and the final rule that incorporated the requirement into Standard No. 213 did not address the issue. 44 FR 72131, December 13, 1979. Accordingly, more than one piece of material may be used.

I hope this information is helpful. If you have any further questions, please contact us.

ID: nht74-3.42

Open

DATE: 05/14/74

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

TO: Dave's Tire & Fuel Oil Corp.

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letters of March 21 and April 22, 1974, in which you ask whether a tire sold as a "blemish" must be guaranteed for workmanship, material, and road hazards.

There are no Federal requirements that manufacturers guarantee blemish (or non-blemish) tires. Such guarantees are within the discretion of each manufacturer. However, Federal Motor Vehicle Safety Standard No. 109 (49 CFR @ 571.109) requires all new passenger car tires to meet minimum safety performance levels for high speed performance, endurance, strength, bead unseating, physical dimensions and tradewear indicators. These requirements apply similarly to both blemish and non-blemish tires.

We have enclosed for your information a copy of the Federal Trade Commission's Tire Advertising and Labeling Guides which contain in Guide 11 requirements for the labeling of blemish tires.

ENC.

ID: nht73-2.25

Open

DATE: 03/15/73

FROM: B.T. DRIVER -- NHTSA MOTOR VEHICLE PROGRAMS

TO: WARREN M. HEATH -- DEPARTMENT OF CALIFORNIA HIGHWAY PATROL

TITLE: N41-34

TEXT: Dear Mr. Heath:

This is in reply to your letter of February 28th to Mr. Dougins W. Toms, Administrator, National Highway Traffic Safety Administration, concerning the mounting of lamps and reflectors on mini-pickup trucks.

The December 8, 1972, letter from Commissioner M. Pudinski was placed in Docket 69-19; Motion No. 3. We inadvertently failed to knowledge this action to Mr. Pudinski.

The visibility requirements of lamps and reflectors in Standard No. 100 are predicated on the normal driving or closed tail gate position. Since the use of motor vehicles, including driving with tail gates down or[Illegible word] lids open or otherwise having the lights and reflectors obscurred by a particular load on the vehicle, is under the jurisdiction of the individual states, we do not anticipate rule making on this subject.

Sincerely,

ID: nht95-1.75

Open

TYPE: INTERPRETATION-NHTSA

DATE: February 24, 1995

FROM: David T. Holland -- President, Europa International, Inc.

TO: Mary Versailles -- Office of Chief Counsel, NHTSA

TITLE: Via fax # 202-366-3820 RE: Request for clarification of passive restraint phase-in requirements of FMVSS 208.

ATTACHMT: ATTACHED TO 4/3/95 LETTER FROM PHILIP R. RECHT TO DAVID T. HOLLAND (A43; STD. 208)

TEXT: Dear Ms. Versailles,

This letter is to follow up our recent phone conversation where-in you acknowledged that if Europa International, Inc. (R91-002) imports Canadian specification MPV's, such as the Chrysler Minivan, that meets the MPV passive restraint phase-in requirement s of FMVSS 208, Europa will be in compliance as it can count these vehicles toward the required percentage.

Please acknowledge this letter by signing below and faxing back or by a letter from your office.

Thank you for your assistance.

Acknowledged by:

Mary Versailles Office of Chief Counsel, NHTSA

ID: nht94-1.45

Open

TYPE: INTERPRETATION-NHTSA

DATE: February 7, 1994

FROM: Martin M. Sackoff, Ph.D. -- Executive Director Of Laboratories, International Testing Laboratories

TO: Office of Chief Counsil -- NHTSA

TITLE: None

ATTACHMT: Attached To Letter Dated 5/12/94 From John Womack To Martin Sackoff (A42; Std. 109)

TEXT: Gentlemen:

The subject of this request is in reference with Motor Vehicle Safety Standard No. 109 - New Pneumatic Tires - Passenger Cars.

The specific question is with reference to S4.2.2.4 Tire Strength, which states "S4.2.2.4 Tire Strength. Each tire shall meet the requirements for minimum breaking energy specified in Table 1 when tested in accordance with S5.3".

I shall very much appreciate receiving a reply concerning the definition or interpretation of the term "breaking" of the tire. Does this mean a blowout of the tire, or simply the breaking of the tire caused by forcing the steel plunger into the tread?

Thank you.

Sincerely,

ID: nht91-6.3

Open

DATE: September 18, 1991

FROM: Al Lipinski -- President, Mini-Max

TO: Hall, Jackson, Rice -- NATSA (NHTSA), Chief Counsel

TITLE: None

ATTACHMT: Attached to letter dated 10-23-91 from Paul Jackson Rice to Al Lipinski (A38; Std. 108; Part 567)

TEXT:

I talked with Steve Kratzke on September 18, 1991 regarding the Dynamic Testing requirements for alterers of certified vehicles.

We are a small conversion company of walk in van type light trucks located in Escanaba, MI. Our projected production for 1992 is 75 vehicles. We do not alter anything forward of the B pillar of a certified vehicle, thus the crash protection system installed by the original manufacturer is not disturbed. We afix an additional label stating the vehicle alterations conform to all applicable FMVSS.

I would appreciate a letter stating what the dynamic testing requirements are for an alterer of a certified vehicle for my files in case this question arises in the future.

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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