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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 14671 - 14680 of 16517
Interpretations Date

ID: nht95-2.66

Open

TYPE: INTERPRETATION-NHTSA

DATE: May 3, 1995

FROM: John Womack -- Acting Chief Counsel, NHTSA

TO: Jeffrey D. Shetler -- Manager of Government Relations, Kawasaki Motors Corp., U.S.A.

TITLE: NONE

ATTACHMT: ATTACHED TO 2/2/95 LETTER FROM JEFFREY D. SHETLER TO NHTSA OFFICE OF CHIEF COUNSEL

TEXT: Dear Mr. Shetler:

This responds to your letter of February 2, 1995, asking whether Safety Standards Nos. 108 and 123 permit a motorcycle turn signal pilot indicator to be green.

You have noted that, under Table III of Standard No. 108, SAE J588 NOV84 is the appropriate standard that the National Highway Traffic Safety Administration (NHTSA) has incorporated by reference for motorcycle turn signal lamps. You have further noted t hat the SAE standard specifies requirements for turn signal pilot indicators if the front turn signal lamps are not readily visible to the driver. Finally, paragraph 5.4.3.3 of SAE J588 specifies that the indicator, if located on the outside of the vehi cle, should emit a yellow-colored light. On the other hand, Standard No. 123, which specifies requirements for turn signal lamp identification, does not specify a color for turn signal pilot indicators.

You believe that SAE J588 was written with passenger cars in mind and that its color and area requirements are specified because the location of an outside indicator lamp is further away than a lamp located inside the vehicle on the instrument panel. Yo u also believe that Standard No. 123 does not need to address distance from the driver's eye because the turn signal lamp will always be within a reasonable distance from the driver's eye. Thus, you have concluded that any pilot lamp color would be acce ptable.

We have reviewed specifications of both the SAE and Standard No. 123. SAE J588 NOV84 Turn Signal Lamps for Use on Motor Vehicles Less Than 2032 MM in Overall Width is incorporated by reference in Standard No. 108, and, under Table III, is the standard s pecified for motorcycle turn signal lamps. Because paragraph S5.1.1 of Standard No. 108 does not contain a section modifying the applicability of J588 to motorcycles, all the requirements of J588 apply to motorcycles, including turn signal pilot indicat ors and their color. All that Standard No. 123 does, through Table III, is to specify the shape of the turn signal indicator. It is silent as to the color of the indicator.

We believe that you are correct in your conclusion that J588 was not written with motorcycles in mind, at least for two-wheeled motorcycles such as Kawasaki makes. Two colors are prescribed by SAE J588, the choice of which depends on the location of the indicator. Under paragraph 5.4.3.2, a green-colored light "with a minimum area of 18 sq. mm." must be used "if the illuminated indicator is located inside the vehicle." Under 5.4.3.3 a yellow-colored light with "a minimum projected illuminated area of 60 sq. mm." must be used "if the illuminated indicators are located on the outside of the vehicle, for example on the front fenders." Since two-wheeled motorcycles do not have enclosed cabins, all references to "inside" and "outside" the vehicle are inap posite.

Since you brought this matter to our attention, we have conducted an informal survey of the color of turn signal indicators on motorcycles sold in the United States. We find that the predominant color is amber, though Harley-Davidson, accounting for 12% of the market, uses green. We view the use of either color as in accord with J588. Therefore, if Kawasaki wishes to change its indicator color from amber to green, it will not violate Standard No. 108 by doing so.

As J588's color specifications are coupled with those for the minimum illuminated area of the display, and you have not raised the question of an appropriate size for a green turn signal indicator, we call your attention to paragraph S5.2.2 of Standard N o. 123 which requires that the display for turn signal lamps and other equipment "be visible to a seated operator under daylight conditions."

If you have any further questions, Taylor Vinson of this office will be glad to answer them for you (202-366-5263).

ID: nht95-2.67

Open

TYPE: INTERPRETATION-NHTSA

DATE: May 3, 1995

FROM: Doug Russell -- Design Engineer, Advance Engineered Products

TO: John Womack -- Acting Chief Counsel, NHTSA

TITLE: FMVSS 121 Paragraph S5.4.2.2 Brake Power

ATTACHMT: ATTACHED TO 06/29/95 LETTER FROM JOHN WOMACK TO DOUG RUSSELL (A43; STD. 121)

TEXT: Dear Sir

Recently, I have been reviewing test data used to certify brake components to FMVSS - 121. Could you please answer two questions which arose as a result of this review:

1. Paragraph S5.4.2.2. of FMVSS - 121 requires that a deceleration be made from 20 mi/hr to a stop at an average rate of 14 ft/s<2>. A maximum service line brake pressure is not specified for this deceleration. Thus, in order to meet the deceleration requirement, a service line pressure exceeding 100 lbs/in<2> could be used despite the fact that tractor - trailer brakes are usually configured to operate at a maximum nominal brake pressure of 100 psi. Are there any limitations on the pressure which c an be used to achieve the required deceleration rates?

2. Test results from one of Advance's suppliers show that the actual deceleration rate was approximately 15% below the 14 ft/s<2> specified in paragraph S5.4.2.2. I have discussed these results with NHTSA's Richard Carter, and according to him the mini mum requirements of FMVSS-121 have not been met. However, according to the supplier, this stop must be done as part of the whole dynamometer test procedure but not meeting the deceleration requirements for this particular stop does not constitute a fall. Have any interpretations been made which allow a reduced deceleration rate?

Please call if you have any questions. Thank-you

ID: nht95-2.68

Open

TYPE: INTERPRETATION-NHTSA

DATE: May 4, 1995

FROM: John Womack -- Acting Chief Counsel, NHTSA

TO: Valter Sforca

ATTACHMT: ATTACHED TO 4/20/95 LETTER FROM VALTER SFORCA TO PHILIPE RECHT (OCC 10866)

TEXT: Dear Mr. Sforca:

This is in reply to your letter of April 20, 1995, asking if there is a regulation that applies to the importation of an "air equalizer for tire pressure."

Although you have not described your device, there are no Federal motor vehicle safety standards that apply to equipment installed in motor vehicles that regulate the air pressure of tires. If you are asked by the U.S. Customs Service to execute an HS-7 Declaration Form at the port of entry, you may check Box 1, declaring that the equipment was manufactured on a date when no applicable Federal motor vehicle safety standard was in effect.

Because this device is motor vehicle equipment, and because you apparently would be its importer, you would be responsible for notifying buyers and recalling it if either you or we decided that it contained a safety related defect.

We don't understand your phrase "the system have a safety valve for the air brakes the truck, for a properly stop". However, if the "air equalizer" is installed by a manufacturer, distributor, dealer, or motor vehicle repair business, that person must n ot knowingly make inoperative any part of a truck's air brake system by installing the air equalizer. I am enclosing a copy of a letter concerning what appears to be a similar device, which will explain this more fully.

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

ID: nht95-2.69

Open

TYPE: INTERPRETATION-NHTSA

DATE: May 4, 1995

FROM: Paul David Wellstone -- United States Senator

TO: Regina Sullivan -- Director, Office of Congressional Affairs, U.S. DOT

TITLE: NONE

ATTACHMT: ATTACHED TO 7/25/95 LETTER FROM JOHN WOMACK TO PAUL DAVID WELLSTONE (PART 571)

TEXT: Dear Ms. Sullivan:

I have been contacted by a constituent of mine, Kris Solberg, about the problem The Grace Christian School is having with the federal government's definition of what constitutes a school bus. I have enclosed a copy of their letter for your review.

The Grace Christian School does not understand why the federal law does not allow the use of 15 passenger vans to transport students to school events.

I would appreciate it if you would review their situation and address their concerns. Please advise me of your findings and direct your response to Scott Adams, a member of my staff, at:

2550 University Avenue W., # 100N St. Paul, MN 55114 612/645-0323

Thank you for your assistance.

Enclosure

GRACE BAPTIST CHURCH

January 31, 1995

Senator Paul Wellstone Hart Office Bldg Washington, DC 20510

Dear Senator Wellstone:

A large number of schools are facing a difficult legal situation with regards to transportation, for which we need your help.

LEGAL SITUATION: The federal government, since the 1970's, has defined a school bus as "a passenger motor vehicle which is designed or used to carry more than 10 passengers in addition to the driver, . . . for the purpose of transporting . . . school stu dents . . .". For years, this definition was largely overlooked. Recently, the federal government has increased pressure on state legislatures to certify state statutes concerning school buses to comply with federal laws.

In 1992, Minnesota passed laws (MN statutes 1992, section 124.225) which comply with the federal definition of a school bus. Our Minnesota laws make it illegal to use a 15 passenger van to transport school students because: 1) it is classified as a bus, but 2) it does not meet all the requirements of a school bus.

HARDSHIP CREATED: 1) Some schools are being forced out of participation in extra-curricular, and even co-curricular activities, because they cannot afford to purchase and operate an official school bus. A small private school from our area, which has a nice van, announced last week that they will have to cancel their winter athletics programs, because they cannot afford to purchase a school bus. 2) The requirement is grossly wasteful. When we send, as we frequently do, sports teams, quiz teams, debat e teams etc., of 5 to 10 students, operating a bus is many times more costly than operating a van.

INEQUITIES OF THE LAW: We have been told that these laws have been passed in the name of safety. However:

1) A 15 passenger van is deemed safe enough for the legal transportation of Sunday School children.

2) A 15 passenger van is safe enough for churches to use in transporting "youth groups".

3) Youth camps, daycares, and youth clubs may use 15 passenger vans.

4) Airports, casinos, motels, etc., may transport passengers, including children, in passenger vans.

5) Station wagons, 7 passenger vans, and automobiles may legally be used to transport school students. These vehicles are not safer than 15 passenger vans.

Conclusion: The 15 passenger van is not an unsafe vehicle. It is, rather, the unfortunate victim of a law written before the 15 passenger van's existence. It is excluded by an unjustified technicality.

PROPOSAL

I. Amend the federal definition of a school bus to read "a vehicle which is designed to transport more than 15 passengers, including the drive . . ." rather than the current," 10 passenger, not including the driver.

II. Require that vehicles designed to transport 15 passengers or less, including vans, wagons, and automobiles, which are used to transport school students be required to be inspected annually, as school buses currently are.

We appreciate your attention to this matter. Please let us know what can be done to improve this.

Sincerely,

Kris Solberg, Principal GRACE CHRISTIAN SCHOOL 600 Lind St. Mankato, MN 56001

ID: nht95-2.7

Open

TYPE: INTERPRETATION-NHTSA

DATE: March 21, 1995

FROM: Philip R. Recht -- Chief Counsel, NHTSA

TO: Paul N. Wagner -- President, Bornemann Products, Inc.

TITLE: NONE

ATTACHMT: ATTACHED TO 1/10/95 LETTER FROM PAUL N. WAGNER TO PHILIP R. RECHT

TEXT: Dear Mr. Wagner:

This responds to your letter of January 10, 1995, requesting further interpretation of how the requirements of Standard No. 207, Seating Systems, would apply to an integrated seat.

Your first question is a follow-up to our December 23, 1994, letter concerning the requirements of S4.2.1 of Standard No. 207. Section S4.2.1 states:

Except for vertical movement of nonlocking suspension type occupant seats in trucks or buses, the seat shall remain in its adjusted position during the application of each force specified in S4.2.

You asked for confirmation that a "rachet-style seat recliner mechanism may not have its adjustment teeth shear during the test, . . . . assuming that the shearing of the recliner's teeth is a change in detent position." This is correct.

Your second question concerns "continuous engagement." You described "continuous engagement" as follows:

continuous engagement . . . . simply implies that the seat recliner or slides will always be in a locked position, even during adjustment. Some slides and recliners, for adjustment purposes, must be "unlocked," or released, allowing for the adjustment t o be made, but then automatically relock when the desired position is achieved; this adjustment is not considered to be as continuously engaged, since the mechanism is in a released state during adjustment.

An apparatus that might be considered to be a continuous engagement device might be a screw-drive mechanism, which can be adjusted by revolution, but would always have a locking feature, even during adjustment (and never be in a released position).

You asked whether the recliner on an integrated seat must have "continuous engagement" to comply with the safety standards.

In the December 23 letter, I explained that NHTSA may choose to test a seat in any of the range of possible reclined positions. However, this does not require "continuous engagement." If a seat has specific adjustment positions, and is released or unloc ked to move between those positions, NHTSA would not test the seat between adjustment positions.

I hope this information has been helpful. If you have any other questions, please contact Mary Versailles of my staff at this address or by phone at (202) 366-2992.

ID: nht95-2.70

Open

TYPE: INTERPRETATION-NHTSA

DATE: May 5, 1995

FROM: John G. Womack -- Acting Chief Counsel, NHTSA

TO: Jiro Doi -- Vice President, Mitsubishi North America, Inc.

TITLE: NONE

ATTACHMT: ATTACHED TO 1/19/95 LETTER FROM Jiro Doi to Philip Recht

TEXT: Dear Mr. Doi:

This is in response to your letter to Philip Recht, former Chief Counsel of the National Highway Traffic Safety Administration (NHTSA), in which you requested an interpretation of the parts-marking requirement of the motor vehicle theft protection standa rd, 49 CFR Part 541.

Your letter asks whether marking the clutch housing on a manual transmission vehicle, or the converter housing on an automatic transmission vehicle, would comply with 49 CFR @ 541.5(a)(2), which requires that the transmission be marked with a VIN or VIN- derivative. Your letter states that the housing is "attached to the transmission via bolts that may be removed allowing the clutch housing (or converter housing) to separate from the transmission."

The answer to your question is that marking the housing but not the transmission would not comply with @ 541.5(a)(2). It is the transmission, and not the housing, that is the component of value to thieves. It is possible that a thief would want to remo ve the transmission from a vehicle without removing the housing, since the transmission is smaller and easier to conceal by itself than it would be with the housing attached. Removal of the transmission alone would be relatively easy to accomplish where the housing is attached to the transmission only by bolts, which is the design you describe in your letter.

If you have any further questions on this matter, please contact Eileen Leahy, an attorney on my staff, at 202-366-5263.

ID: nht95-2.71

Open

TYPE: INTERPRETATION-NHTSA

DATE: May 9, 1995

FROM: Ron Hooker -- Program Administrator, Division of Weights and Measures, Missouri Department of Agriculture

TO: Mr. John Womack -- Chief Counsel, NHTSA

TITLE: CNG Motor Vehicle Fuel System Safety

ATTACHMT: ATTACHED TO 6/8/95 LETTER FROM JOHN WOMACK TO RON HOOKER (A43; VSA 103(A) 303)

TEXT: Dear Mr. Womack:

In 1991 the Missouri General Assembly passed legislation mandating a Fuel Conservation Program for state vehicles. Various alternative fuels were addressed in the legislation including natural gas.

At the time the legislation was passed, there were no state regulations setting forth safety standards and/or guidelines for compressed natural gas motor vehicle fuel systems.

Because of the concern for safety and the need for specific guidelines for CNG motor vehicle fuels systems, the Highway Patrol, Public Service Commission and our agency studied the issue and a determination was made that the Missouri Department of Agricu lture should be the "lead" agency since regulations relating to LP gas motor vehicle fuels systems had been established by Agriculture in 1983.

In 1994 the General Assembly passed legislation giving the Department of Agriculture the authority to promulgate regulations relating to CNG motor vehicle fuel system safety. We are now attempting to determine what the extent of the regulations should/c an be.

Several agencies, both private and public, are involved as a rule making committee and anxious for regulations/guidelines to be established so that CNG can be utilized as an alternative motor fuel choice.

With exception of fuel container design and fuel container and system integrity, does the Department of Agriculture have the authority, under federal regulations, to implement regulations and/or adopt national standards (i.e. NFPA 52) relating to CNG mot or vehicle fuel system safety.

If the department does have authority or limited authority, could you please address those areas and communicate them to me at your earliest convenience.

I sincerely appreciate your assistance in this matter.

ID: nht95-2.72

Open

TYPE: INTERPRETATION-NHTSA

DATE: May 9, 1995

FROM: John Womack -- Acting Chief Counsel, NHTSA

TO: Lance Tunick -- Vehicle Science Corporation

TITLE: NONE

ATTACHMT: ATTACHED TO 4/19/95 LETTER FROM LANCE TUNICK TO MARY VERSAILLES (OCC 1085)

TEXT: Dear Mr. Tunick:

This responds to your FAX of April 19, 1995, requesting clarification of an April 3, 1995, letter from this office. You asked for verification that the "seat belt anchorages in the following scenario are exempt from the location requirement of Standard No. 210:

A vehicle with 2 front seating positions that is fitted with an air bag and manual three-point seat belt at each position, and such restraint meets the frontal crash protection requirements of S5.1 of Standard No. 208 with the air bags alone and with the belts and air bags together, but the belts alone are not crash tested under FMVSS 208."

Your understanding is correct.

I hope this information has been helpful. If you have other questions or need some additional information, please contact Mary Versailles of my staff at this address or by phone at (202) 366-2992.

ID: nht95-2.73

Open

TYPE: INTERPRETATION-NHTSA

DATE: May 9, 1995

FROM: John Womack -- Acting Chief Counsel, NHTSA

TO: Musa K. Farmand -- Gonzalez & Farmand, P.A.

TITLE: NONE

ATTACHMT: ATTACHED TO 04/27/95 LETTER FROM MUSA K. FARMAND TO MARY VERSAILLES

TEXT: Dear Mr. Farmand:

This responds to your letter of April 27, 1995. Your letter concerns a law suit in which you represent plaintiffs injured in an automobile accident. In this law suit, the counsel for the defendant has moved to amend his answer to assert that 49 CFR 571 .208, paragraph S4.1.5.2(c)(2) requires each state to allow for mitigation of damages in any seat belt use law and that paragraph preempts the Florida mandatory seat belt law. According to your letter, the Florida law "does not allow a mitigation of dam ages defense with respect to an alleged failure to wear a seat belt." As explained below, the National Highway Traffic Safety Administration agrees with you that the Florida safety belt use law is neither expressly nor impliedly preempted by Federal law.

Purpose of Paragraph S4.1.5.2(c) (2)

Before discussing the issue of preemption, I want to discuss the background and purpose of Paragraph S4.1.5.2(c)(2). That paragraph was added to Standard No. 208, Occupant Crash Protection (49 CFR 571.208) as part of a final rule issued July 17, 1984 co ncerning automatic restraints (49 FR 28962). That final rule required all new cars to have automatic protection (air bags or automatic belts) starting in the 1990 model year. The final rule included a provision that the automatic restraint requirement would be rescinded if the Secretary of Transportation determined, not later than April 1, 1989, that a sufficient number of States had enacted belt use laws meeting certain minimum criteria to cover at least two-thirds of the U.S. population (paragraph S 4.1.5). Under S4.1.5, the Secretary was not required to make any determination about any State safety belt laws. In fact, the Secretary never did so, in part because not enough States adopted mandatory seat belt use laws of any sort prior to April 1, 1 989. Because no determination was made under S4.1.5, the automatic restraint requirements are now in effect for all passenger cars.

The minimum criteria were set forth in S4.1.5.2 of Standard No. 208. n1 One of the criteria was "a provision specifying that the violation of the belt usage requirement may be used to mitigate damages . . ." (S4.1.5.2(c)(2)). However, S4.1.5 neither pur ported to require nor was intended to require States to enact safety belt use laws. In addition, S4.1.5 did not require that any State safety belt use laws had to incorporate the minimum criteria of S4.1.5.2. Paragraph S4.1.5 merely provided that the S ecretary would rescind the automatic restraint requirement if he or she determined that a sufficient number of States enacted laws which met the criteria of S4.1.5.2 by April 1, 1989.

n1 Your letter correctly notes that this provision was deleted from Standard No. 208 by a final rule issued on September 2, 1993 (58 FR 46551).

Preemption

The Florida safety belt use law is not and never has been either expressly or impliedly preempted by Federal law.

Standard No. 208 was issued under 49 U.S.C. Chapter 301 which expressly preempts state laws only to the extent provided by section 30103. That section provides for the express preemption of State motor vehicle safety standards that are not identical to Federal standards. However, the Florida seat belt law is not a motor vehicle safety standard within the meaning of Chapter 301, since it does not regulate motor vehicle or motor vehicle equipment performance. Accordingly, the Florida law is not express ly preempted.

The Florida law is not impliedly preempted because (1) Congress has not occupied the field of regulation of the behavior of motor vehicle occupants; and (2) the Florida seat belt law does not conflict with any Federal law or interfere with the objectives of Federal law.

I hope this information has been helpful. If you have other questions or need some additional information, please contact Mary Versailles of my staff at this address or by phone at (202) 366-2992.

ID: nht95-2.74

Open

TYPE: INTERPRETATION-NHTSA

DATE: May 9, 1995

FROM: John Womack -- Acting Chief Counsel, NHTSA

TO: Takashi Adachi -- Manager, Ichikoh Industries, Ltd.

TITLE: NONE

ATTACHMT: ATTACHED TO 3/14/95 LETTER FROM TAKASHI ADACHI TO RICHARD L. VAN IDERSTIN (OCC 10857)

TEXT: Dear Mr. Adachi:

This is in reply to your letter of March 14, 1995, to Richard Van Iderstine of this agency, asking for an interpretation of Motor Vehicle Safety Standard No. 108 as it applies to a reflex reflector design that you attached. This design shows a single re flector 2 inches in height mounted behind a clear outer lens which is bisected horizontally by an opaque strip 6mm (.25 in.) wide, giving the impression from the exterior of two reflectors, one .75 in. high above the divider, and one that is 1.00 in. in height, below the divider.

You have asked whether the "structure of the reflex reflector conforms to FMVSS 108," and whether photometric conformance is judged with respect to the single reflector crossed by the opaque strip, or whether both the upper and lower portions of the bise cted reflector must meet the photometric specification.

Standard No. 108 is a performance standard, not a design standard. The standard does not specify any requirements concerning the structure of reflectors. The applicable requirements for reflex reflectors are those of SAE Standard J594f. Reflex Reflecto rs January 1977, which Standard No. 108 incorporates by reference. Your reflector should be tested as a single reflector according to the procedures set forth in J594f. If the reflector does not meet the photometric performance requirements of that sta ndard, you may add sufficient reflective elements to the reflector design until conformance is achieved. There is no need to test the upper and lower portions as separate reflectors.

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

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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