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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 12371 - 12380 of 16490
Interpretations Date

ID: nht68-2.49

Open

DATE: 09/04/68

FROM: AUTHOR UNAVAILABLE; Charles A. Baker; NHTSA

TO: General Body Company

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your letter of August 1, 1968, to Messrs. Eugene Laskin and J. E. Leysath of this Bureau, requesting comments on the Distributors Association's bulletins on lamps, reflective devices and associated equipment required by Motor Vehicle Safety Standard No. 108.

The five bulletins adequately illustrate the requirements of Standard No. 108 to the vehicles shown except as follows:

(1) Pages 1, 3, and 4 -- The statement "Identification, clearance and side market lights and side and rear reflectors are not required unless vehicle with body is 80 or more inches wide overall" should be changed, because Table III of Standard No. 108, effective January 1, 1969, specifics requirements for side marker lights and side and rear reflex reflectors on vehicles less than 80 inches wide.

(2) Page 2 -- The numbers indicating clearance and identification lamps in lower right view should be reversed, i.e., 10 and 11, respectively. Also, the turn, tail and stop lamps do not appear to be located as far apart as practicable.

(3) Page 4 -- The front clearance lamps mounted on the chassis cab are optional, because those on the van body meet the requirements of Standard No. 103.

(4) Page 5 -- (a) Identification and clearance lamps are not required if vehicle width is under 80 inches. (b) Two red reflectors are required on the rear of the vehicle.

(5) General, all pages -- Paragraph S3.1.1.6 permits vehicles less than 80 inches overall width manufactured before January 1, 1970, to be equipped with a combination of two side marker lamps and side marker reflectors on each side instead of two each as specified in Table III.

(6) General, Pages 1 through 4 -- Parking lamps are not required on vehicles that are 80 inches or were in overall width.

With respect to the requirements of Standard No. 108, this Bureau does not issue approvals on items of lighting equipment or on vehicle designs incorporating this equipment. Therefore, the above comments are for your information only and in no way relieve the vehicle manufacturer from his responsibility for certifying hat the assembled vehicle meets the requirements of the standard.

ID: nht72-6.42

Open

DATE: 08/29/72

FROM: AUTHOR UNAVAILABLE; Robert L. Carter; NHTSA

TO: B. F. Goodrich Tire Company

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your petition for rulemaking, submitted July 30, 1971, to amend Motor Vehicle Safety Standard No. 109 (49 CFR @ 571.109) and the Tire Identification and Recordkeeping Regulations (49 CFR Part 574). Your petition requests that Standard No. 109 be amended to provide for a special tire category for folding sidewall-reduced tread tires, of which the "Space Saver Spare" tire you manufacture is an example. You request specifically that requirements for these tires differ from conventional tires as follows: lower minimum breaking-energy values in the strength test (S4.2.2.4, Table II); modified minimum size factors for certain tire size designations which you list; elimination of the condition that the tire be mounted without lubricant for the bead unseating test (S4.2.2.3); and allowing the tire identification number to be placed on the lower sidewall (49 CFR 574.5). For the reasons stated below, your petition is hereby denied insofar as it requests modifications to the strength and bead unseating requirements of Standard No. 109, and the requirements of Part 574. We make certain recommendations herein regarding your request for modification of the minimum size factors of Standard No. 109.

The basis for your request for lower breaking-energy values in the strength test is that the values you request represent a level of performance equal to that of a conventional tire having the same amount of tread remaining as a new folding sidewall-reduced tread tire. The NHTSA cannot accept this argument as a valid basis for specifying lower breaking-energy value requirements for folding sidewall-reduced tread tires The requirements specified for the strength test are considered to be necessary minimum requirements for all new passenger car tires. Consequently, persons who purchase new tires, regardless of their construction, are entitled to at least this level of performance, and not the level of performance represented by a used tire.

The NHTSA does not believe, similarly, that you have presented a sufficient basis for elimination of the condition, in the bead unseating test procedure, that the tire be mounted for the test without the use of lubricant. While the NHTSA concurs in the benefits of run-flat performance, which the "Space Saver Spare" appears to provide, we do not believe that this advantage outweighs the necessity that the tire conform to the bead unseating requirements when mounted without lubrication. The NHTSA believes the possibility that tires will be mounted without lubrication in the field is sufficiently great to warrant the retention of this condition in the standard's test procedure.

We also do not consider sufficient the justification you provide for your request that the identification number required pursuant to Part 574 be allowed to be placed on the lower sidewall of the tire. Your statement to the effect that no problems are presented if the number "wears off" ignores the fact that the number must be retained on the tire for purposes of identification should a defect notification or recall campaign be instituted.

With reference to your request for modification of the (Illegible Word) size factor for the tire size designations which you list, believe B. F. Goodrich should petition, in accordance with guidelines published October 5, 1968 (33 F.R. 14964), to amend the Appendices of Standards Nos. 109 and 110 to provide that folding sidewall-reduced tread tires be added as a separate tire type, including new size designations and corresponding values for section width and minimum size factor that you consider appropriate.

[GRAPHICS OMITTED]

[GRAPHICS OMITTED]

[GRAPHICS OMITTED]

[GRAPHICS OMITTED]

ID: nht93-8.31

Open

DATE: November 23, 1993

FROM: John Womack -- Acting Chief Counsel, NHTSA

TO: Amantha L. Barbee -- Sales Coordinator, Thomas Built Buses, Inc.

TITLE: None

ATTACHMT: Attached to letter dated 10/14/93 from Amantha L. Barbee to John Womack (OCC-9220), letter dated 1/26/93 from John Womack to Paul David Wellstone, letter dated 8/21/92 from Paul Jackson Rice to Chuck Anderson, and letter dated 9/27/85 from Jeffrey R. Miller to Charles Pekow

TEXT:

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.

ID: 21341.ztv

Open

Mr. Eugene Farber
S&HFC Co-Chair
SAE International
31811 Vallen Court
Beverly Hills, MI 48025

Re: Request for Interpretation of S5.5.4, FMVSS No. 108

Dear Mr. Farber:

This is in reply to your letter of February 21, 2000, asking for an interpretation of S5.5.4 of Federal Motor Vehicle Safety Standard No. 108, Lamps, Reflective Devices and Associated Equipment.

Paragraph S5.5.4 requires in pertinent part that "The stop lamps shall be activated upon application of the service brakes." You have asked two questions with regard to this requirement.

Your first question is whether it is "permissible to illuminate stoplamps when the service brakes are automatically applied (i.e., the driver does not depress the brake pedal) for purposes of whole vehicle deceleration." The SAE Standards on stop lamps that are incorporated by reference, J586 MAY84 and J1398 MAY85, define stop lamps as "Lamps . . . [which] indicate the intention of the operator of a vehicle to stop or diminish speed by braking." Given that your stated purpose of either manual or automatic service brake application is to diminish vehicle speed, the stop lamp must be illuminated. Vehicles whose service brakes are applied with a resulting diminishing of speed would be noncompliant if the stop lamps did not illuminate.

Your second question is whether it is "permissible that the stoplamps be illuminated when other mechanisms such as transmission downshifting or engine retarders are used to achieve whole vehicle decelerations in excess of the normally achievable coast-down deceleration." On

April 10, 1992, this Office informed Lance Watt of the Flxible Corporation that Standard No. 108 does not require that the stop lamps be activated when a brake retarder is activated. We appear not to have addressed transmission downshifting, but we see no difference in functional effect between it and an engine retarder. While the Watt interpretation appears inconsistent with our views in the preceding paragraph, because, in either case, the vehicle would decelerate at a higher rate than normal coastdown, the former involves brake application, while this one does not. It is possible that, upon further review, the Watt interpretation might be superceded by rulemaking to clarify the conditions under which the stop lamps must be illuminated.

We note that S5.1.3 of Standard No. 108 provides that "No additional lamp, reflective device or item of associated equipment shall be installed that impairs the effectiveness of lighting equipment required by" the standard. In this case, when a vehicle is slowed by downshifting or an engine retarder, from the perspective of the following driver, it would be equivalent to what would occur if the service brakes were applied. Therefore, it would be permissible for the stop lamps to be illuminated under this scenario, since such illumination would not create any confusion in the mind of a following driver and thus would not "impair the effectiveness" of the required stop lamps.

If you have any further questions, you may refer them to Taylor Vinson of this Office (202-366-5263).

Sincerely,
Frank Seales, Jr.
Chief Counsel
ref:108
d.5/26/00

2000

ID: nht68-1.16

Open

DATE: 07/25/68

FROM: AUTHOR UNAVAILABLE; John D. Robinson; NHTSA

TO: Robert Bosch GMBH

COPYEE: DEPT. OF TRANSPORTATION

TITLE: FMVSS INTERPRETATION

TEXT: This will acknowledge receipt of your letter dated May 21, 1968 copy of which was forwarded to the Secretary of Transportation, concerning the application of Federal Safety Standard 108 to lighting unise that are now being manufactured by Robert Bosch Gmbh.

The joint regulations of the Bureau of Customs and the Department of Transportation, copy enclosed, provides in section 12.80(b)(2)(i) for the importation of a non-conforming vehicle or equipment item if they were manufactured on a date when there were no applicable safety standards in force. Therefore, these lighting units manufactured prior to January 1, 1969, and offered for importation into the United States do not have to be in conformity with Federal Safety Standard 108.

Since your inquiry concerns a specific safety standard not yet in effect, we are forwarding your letter to the Department of Transportation, Highway Safety Bureau, Washington, D.C., for their consideration and direct reply.

Sincerely yours,

Enclosure 50359

ATTACH.

ROBERT BOSCH GMBH

Lester D. Johnson -- Commissioner of Customs, Department of the Treasury/ Bureau of Customs

CC: Alan S. (Illegible Word) Secretary of Transportation

May 21, 1968

Subject: Title 19-Customs Duties (T.D. 68-16) - Part 12-Special Classes of Merchandise - Importation of Motor Vehicles and Items of Motor Vehicle Equipment - Federal Register Vol. 33, No. 6 of January 10, 1968.

Gentlemen:

With the above mentioned publication, certain conditions are imposed for the importation of motor vehicle equipment into the United States.

In our opinion, one case occuring in practice is not covered by the exception granted under section (b). This is the case when replacement items are delivered for automotive vehicles manufactured before entering into force of a relevant Federal Safety Standard.

We are for instance to deliver lighting units equipped with white parking lamps for passenger cars which are evidently not conforming to Federal Safety Standard 108.

The problem is now, whether it is possible and missible to import such items and other ones into the United States after January 1, 1969. We add that it is well evident that such items are needed after this date, because vehicles are already equipped in such a manner and it would in our opinion be too costly to replace two lighting units conforming to the relevant Federal Safety Standard, if only one replacement unit not conforming to the relevant Federal Safety Standard is needed for a passenger car manufactured before January 1, (Illegible Words)

We should be very glad to have a repid answer from you, since we have already now to care for corresponding replacement units. Leadtime is already now very scarce.

Very truly yours,

A. Hammerstein

ID: 1984-1.19

Open

TYPE: INTERPRETATION-NHTSA

DATE: 03/05/84

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: Stapleton Public Schools

TITLE: FMVSR INTERPRETATION

TEXT:

Mr. Ben Barbie Stapleton Public Schools P.O. Box 125 Stapleton, Nebraska 69163

Dear Mr. Barbie:

This is in further reply to your phone call of February 13, 1984, to the National Highway Traffic Safety Administration regarding the remanufacture of school buses using older model bus bodies on new chassis. You asked whether the school bus safety standards apply to a school bus manufactured with a 1976 model year body mounted on a new chassis.

The applicability of Federal Motor Vehicle Safety Standards is determined by the date of manufacture of the motor vehicle. For vehicles that are completed in several stages, the manufacturer can treat as the date of manufacture the date of the incomplete vehicle, the date of final completion of the vehicle, or a date between those two dates. An "incomplete vehicle" is defined in 49 CFR Part 568, Vehicles Manufactured in Two or More Stages, as:

an assemblage consisting, as a minimum, of frame and chassis structure, power train, steering system, suspension system, and braking system, to the extent that those systems are to be part of the completed vehicle, that requires further manufacturing operations, other than the addition of readily attachable components, such as mirrors or tire and rim assemblies, or minor finishing operations such as painting, to become a completed vehicle.

The effective date of the school bus safety standards was April 1, 1977. Since the date of manufacture of the school bus chassis is after April 1, 1977, and the date of completion of the vehicle is after April 1, 1977, the completed school bus must meet the requirements of the school bus safety standards. It is extremely unlikely that the 1976 model year body will comply with the school bus standards since the body was manufactured before the effective date of the school bus standards. If your completed vehicle does not comply with the safety standards, your manufacturer, distributor, or dealer cannot certify it as conforming to such standards.

Sincerely,

Frank Berndt Chief Counsel

ID: nht76-3.27

Open

DATE: 05/12/76

FROM: AUTHOR UNAVAILABLE; Stephen P. Wood; NHTSA

TO: Willamette Wheel Inc.

TITLE: FMVSR INTERPRETATION

TEXT: I am writing in response to your April 21, 1976, telephone conversation with Mark Schwimmer of this office, concerning the modification work that you perform on previously certified Datsun pickup trucks, which consists of converting them from two-wheel- to four-wheel-drive vehicles.

As indicated in the October 30, 1975, letter from Richard B. Dyson to you, you are a vehicle alterer who is subject to the requirements of 49 CFR 567.7. That section requires that you affix a label to the vehicle stating that, as altered, the vehicle conforms to applicable Federal motor vehicle safety standards.

The Federal government does not certify or otherwise issue advance approval of motor vehicles. As Mr. Schwimmer explained, the statement on the label constitutes your certification of conformity. If you fail to provide this certification, or if in the exercise of due care you have reason to know that it is false or misleading, you are subject to civil penalties under the National Traffic and Motor Vehicle Safety Act of 1966, as amended.

All altered vehicles must comply fully with all applicable safety standards. Therefore, as Mr. Schwimmer further explained, you would not be relieved of the requirements of @ 567.7 simply by virtue of the fact that, as altered, the vehicle complied fully with the standards. You would be relieved of the requirements only if both of the following conditions were met:

(i) the alteration is performed solely by the addition, substitution, or removal of readily attachable components such as tire and rim assemblies, or by minor finishing operations such as painting; and

(ii) the stated weight ratings of the vehicle are still valid.

Because the conversion of the vehicles in question does not meet the first condition, you are subject to the requirements of @ 567.7. Please note further that, if your modifications affect the validity of the weight ratings assigned to the vehicles by Datsun, your label must show valid, modified ratings.

An information sheet entitled "Where to Obtain Federal Motor Vehicle Safety Standards and Regulations" is enclosed for your convenience.

ID: 1982-1.39

Open

TYPE: INTERPRETATION-NHTSA

DATE: 04/02/82

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: American Transportation Corporation

TITLE: FMVSR INTERPRETATION

TEXT: This responds to your February 27, 1982, letter asking whether a vehicle which transports 10 or fewer persons could be classified as a bus if it is built with a traditional bus body. The vehicle transports fewer persons than normal, because it is designed for wheelchair occupants. The answer to your question is no.

The classification of a vehicle as a bus or a multipurpose passenger vehicle for the purposes of the Federal motor vehicle definitions of "bus" and "multipurpose passenger vehicle" in 49 CFR 571.3. A vehicle that transports the number of persons that you mentioned in your letter must be classified as a multipurpose passenger vehicle. The fact that the vehicle is designed as a bus has no relevance to its classification. The controlling factor is passenger capacity.

Since the vehicle would be a multipurpose passenger vehicle, it would be required to comply with all of the standards applicable to those vehicles. This would include complaince with Standard No. 206, Door Locks and Door Retention Components.

SINCERELY,

February 27, 1982

Office of Chief Counsil United States Department of Transportation National Highway Traffic Safety Admn.

Dear Sir:

American Transportation Corporation manufacturers buses used on both school buses and as transit buses.

One of the small (under 10,000# GVWR) buses, when equipped for transporting non-ambulatory passengers in wheel chairs could reduce the passenger capacity to 10 persons or less. Since the bus body does not change, could this bus still be classified as a bus and not a multipurpose passenger vehicle (MPV)?

If the classification should have to be MPV, would the entrance door and the special access door to the loading and unloading lift have to meet the performance requirements of FMVSS 206 for door locks and door retention components?

We would appreciate very much an early reply. Thank you in advance for your consideration.

E. M. Ryan, Sr. Project Engineer-Specifications

CC: TERRY HARRELL

ID: 7434

Open

Mr. Eugene Welker
774 Harbor Island
Clearwater, FL 34630

Dear Mr. Welker:

This responds to your letter about a mirror system designed to improve a driver's view of areas behind a motor vehicle. You explained that a 35" vertical post would be bolted near a vehicle's rear bumper. This would result in a mirror being located a few inches above the top rear window stop light and facing forward at a 45 angle. You asked whether such a device would be legal. The following discussion and the enclosed information sheet, "Information for New Manufacturers of Motor Vehicles and Motor Vehicle Equipment," explain your responsibility under NHTSA's regulation.

By way of background information, the National Highway Traffic Safety Administration (NHTSA) does not approve, endorse, or certify motor vehicles or motor vehicle equipment. Under the National Traffic and Motor Vehicle Safety Act ("Safety Act"), the manufacturer is responsible for certifying that its vehicles or equipment comply with applicable Federal motor vehicle safety standards. The Safety Act requires that these safety standards establish minimum levels of performance for vehicles or equipment. Once the performance level has been established, vehicle or equipment manufacturers are free to choose any means they wish to achieve the required level of performance.

NHTSA has exercised its authority to establish performance requirements for new vehicles in Standard No. 111, Rearview Mirrors (49 CFR 571.111, copy enclosed). Standard No. 111 establishes performance and location requirements for rearview mirrors installed in any new vehicle. This means that the vehicle manufacturer must certify that each vehicle it manufactures complies with the specified requirements. Standard No. 111 requires that passenger cars be equipped with an inside rearview mirror and a driver's side outside rearview mirror that provide the field-of-view specified in S5.1.1. A passenger's side outside rearview mirror is required in situations where the inside rearview mirror does not provide the specified field-of-view. Additional requirements for other vehicle types are set forth in S6, S7, and S8.

No provision in the Standard specifies requirements for a mirror that attaches to the vehicle's rear bumper. Accordingly, a mirror like yours would not be prohibited from being installed on any vehicle by the current requirements in Standard No. 111. Accordingly such a mirror would be permitted, but only as a supplement to the required mirrors.

In installing the mirror, one must take care to avoid obscuring the vehicle's lighting devices, including the center highmounted stop lamps (CHMSL).

Please be aware that NHTSA does not regulate vehicles while they are in use. The American Association of Motor Vehicle Administrators, 4600 Washington Blvd, Arlington, VA 22203 may be able to advise you about the laws of the individual States related to the use of equipment such as your own.

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,

Paul Jackson Rice Chief Counsel ref:111 d:8/7/92

1992

ID: nht92-4.44

Open

DATE: August 7, 1992

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA; Signature by Kenneth N. Weinstein

TO: Eugene Welker

TITLE: None

ATTACHMT: Attached to letter dated 6/22/82 (should be 6/22/92) from Eugene J. Welker to Jackson Rice (OCC 7434)

TEXT:

This responds to your letter about a mirror system designed to improve a driver's view of areas behind a motor vehicle. You explained that a 35" vertical post would be bolted near a vehicle's rear bumper. This would result in a mirror being located a few inches above the top rear window stop light and facing forward at a 45 degree angle. You asked whether such a device would be legal. The following discussion and the enclosed information sheet, "Information for New Manufacturers of Motor Vehicles and Motor Vehicle Equipment," explain your responsibility under NHTSA's regulation.

By way of background information, the National Highway Traffic Safety Administration (NHTSA) does not approve, endorse, or certify motor vehicles or motor vehicle equipment. Under the National Traffic and Motor Vehicle Safety Act ("Safety Act"), the manufacturer is responsible for certifying that its vehicles or equipment comply with applicable Federal motor vehicle safety standards. The Safety Act requires that these safety standards establish minimum levels of performance for vehicles or equipment. Once the performance level has been established, vehicle or equipment manufacturers are free to choose any means they wish to achieve the required level of performance.

NHTSA has exercised its authority to establish performance requirements for new vehicles in Standard No. 111, Rearview Mirrors (49 CFR S571.111, copy enclosed). Standard No. 111 establishes performance and location requirements for rearview mirrors installed in any new vehicle. This means that the vehicle manufacturer must certify that each vehicle it manufactures complies with the specified requirements. Standard No. 111 requires that passenger cars be equipped with an inside rearview mirror and a driver's side outside rearview mirror that provide the field-of-view specified in S5.1.1. A passenger's side outside rearview mirror is required in situations where the inside rearview mirror does not provide the specified field-of-view. Additional requirements for other vehicle types are set forth in S6, S7, and S8.

No provision in the Standard specifies requirements for a mirror that attaches to the vehicle's rear bumper. Accordingly, a mirror like yours would not be prohibited from being installed on any vehicle by the current requirements in Standard No. 111. Accordingly such a mirror would be permitted, but only as a supplement to the required mirrors. In installing the mirror, one must take care to avoid obscuring the vehicle's lighting devices, including the center highmounted stop lamps (CHMSL).

Please be aware that NHTSA does not regulate vehicles while they are in use. The American Association of Motor Vehicle Administrators, 4600 Washington Blvd, Arlington, VA 22203 may be able to advise you about the laws of the individual States related to the use of equipment such as your own.

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.

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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