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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 9931 - 9940 of 16510
Interpretations Date
 search results table

ID: nht88-2.98

Open

TYPE: INTERPRETATION-NHTSA

DATE: 08/11/88

FROM: ROBERT L. RIPLEY -- PRESIDENT KNAACK MANUFACTURING COMPANY

TO: ERICA JONES -- OFFICE OF THE CHIEF COUNCIL NHTSA

TITLE: NONE

ATTACHMT: ATTACHED TO LETTER DATED 11/28/88 TO ROBERT L. RIPLEY FROM ERIKA Z. JONES, REDBOOK A32; STANDARD 556

TEXT: Dear Ms. Jones:

I am enclosing copies of our three catalogs of products which we manufacture. I would appreciate it if you would review these catalogs and tell us whether we are required to file under Part 566, which requires motor vehicles and motor vehicle equipment manufacturers to supply NHTSA with information identifying themselves and describing products.

I will await your reply. Thank you for your consideration.

Sincerely,

ENCLOSURE

ID: nht88-2.99

Open

TYPE: INTERPRETATION-NHTSA

DATE: 08/11/88

FROM: ERIKA Z. JONES -- CHIEF COUNSEL NHTSA

TO: J. MIKE CALLAHAN -- PRECISION IMAGES

TITLE: NONE

ATTACHMT: LETTER DATED 04/14/87 TO TAYLOR VINSON FROM J MIKE CALLAHAN; OCC-409; LETTER DATED 11/19/87 TO ROGER M. COX FROM ERIKA Z JONES, STANDARD 108; LETTER DATED 09/03/87 TO DAVID M. ROMANSKY, FROM ERIKA Z JONES

TEXT: Dear Mr. Callahan:

This is in reply to your letter of April 14, 1987, to Mr. Vinson of this office with respect to your representation of a company "that will be selling plastic name plates which would be installed behind the red-lens of the third brake light." You stated that "these are to be sold to new car dealerships. When the driver of the car steps on the brake the dealer's name lights up." You ask for letters regarding the legality of the name plates for 24 States.

We regret the delay in responding to your request. When Mr. Vinson tried to reach you by phone this week he was told that you had already received a letter, and that the answer was negative. Perhaps that letter came from one of the 24 States listed in your letter. We are unable to advise you of the legality under State laws, but I have enclosed representative interpretation letters of this agency on the legality of similar devices under Federal law.

ENCLOSURE

Sincerely,

ID: nht88-3.1

Open

TYPE: INTERPRETATION-NHTSA

DATE: 08/11/88

FROM: ERIKA Z. JONES -- CHIEF COUNSEL NHTSA

TO: JAY V. WRIGHT -- PAGE AVJET CORP.

TITLE: NONE

ATTACHMT: LETTER DATED 04/21/88, TO CHIEF COUNSEL NHTSA, FROM JAY V. WRIGHT, OCC - 1930

TEXT: Dear Mr. Wright:

This is in response to your letter of April 21, 1988, asking whether a vehicle produced by your company is a motor vehicle subject to the requirements of the Federal motor vehicle safety standards. This vehicle, referred to as a hydrant truck, consists of a chassis-cab with an equipment platform mounted on its rear. According to your letter, the platform would be equipped with accessories that allow the vehicle to be used to filter and meter aircraft fuels as fuel is pumped from airport storage tanks i nto aircraft.

Section 102(3) of the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1391(3)) defines a "motor vehicle" as any vehicle driven or drawn by mechanical power manufactured primarily for use on the public streets, roads, and highways, except any veh icle operated exclusively on a rail or rails.

We have interpreted this language as follows. On the one hand, vehicles that are equipped with tracks or are otherwise incapable of highway travel are plainly not motor vehicles. Agricultural equipment, such as tractors, are not motor vehicles. In add ition, vehicles intended and sold solely for off-road use are not motor vehicles, even though they may be operationally capable of highway travel. Examples include airport runway vehicles.

On the other hand, vehicles that use the public roads on a necessary and recurring basis are motor vehicles. For instance, jeep-type utility vehicles are plainly motor vehicles, even though they are equipped with special features to permit off-road oper ation. We have found vehicles to be motor vehicles if their on-road use is substantial, even though these vehicles' predominant intended use is off-road. Further, if a vehicle is readily usable on the public roads and is in fact used on the public road s by a substantial number of vehicle owners, NHTSA has found that the

vehicle is a "motor vehicle." This finding was made in the case of dune buggies, regardless of the manufacturers' stated intent that the vehicles were to be used off-road only.

You stated in your letter that this vehicle is not "perceived as being moved over public roads or from airport to airport in its daily use." It appears that this vehicle is intended and sold solely for off-road use, even though the vehicle appears operat ionally capable of highway travel. Based on the information provided in your letter, we conclude that your company's "Hydrant Truck" does not appear to be a motor vehicle. However, we will reexamine this conclusion if we learn that, for example, the ve hicle is regularly being used on the public roads.

We note that if your vehicle ever came to be regarded as a motor vehicle, there are probably few changes that would have to be made to bring it into compliance with the Federal Motor Vehicle Safety Standards (FMVSS). NHTSA encourages (but cannot require ) you to make these changes. The chassis-cab used to produce the hydrant truck already has been certified by its manufacturer as an incomplete vehicle. Therefore, in order to achieve compliance, it is likely that few standards would require any changes by your company. One such standard is FMVSS 108, Lamps, reflective devices, and associated equipment. Additional changes might also be required if the weight added by the equipment platform exceeds any weight maxima specified by the chassis-cab manufa cturer in making his certification.

Sincerely,

ID: nht88-3.10

Open

TYPE: INTERPRETATION-NHTSA

DATE: 08/19/88

FROM: ERIKA Z. JONES -- CHIEF COUNSEL NHTSA

TO: DOUGLAS H. BOSCO -- HOUSE OF REPRESENTATIVES

TITLE: NONE

ATTACHMT: LETTER DATED 06/16/88, TO ERIKA Z. JONES, FROM DOUGLAS H. BOSCO; LETTER DATED 08/03/87 TO DOUGLAS H. BOSCO FROM ERIKA Z. JONES; LETTER DATED 06/09/88 TO JERRY K. YOST FROM L. F ROLLIN; LETTER DATED 03/28/88 TO C-MORE-LITE JERRYS SERVICE FROM DO N O. HORNING RE TEST REPORT NO 92606; 1988 LETTER TO ERIKA Z. JONES FROM JERRY SERVICE

TEXT: Dear Mr. Bosco:

This is in reply to your letter of June 16, 1988, with reference to your constituent Jerry Yost of Occidental. Thank you for enclosing our previous correspondence on Mr. Yost's C-More Light invention. This device is a relay which would allow a headlamp 's lower beam to remain in operation when the upper beam is activated. In my reply of August 3, 1987, I advised you that the Federal motor vehicle lighting standard explicitly prohibits simultaneous activation of upper and lower beams in four-lamp headl ighting systems other than the one we call Type F (S4.5.8 of 49 CFR 571.108 Motor Vehicle Safety Standard No. 108). I explained that our historical concern has been that the maximum candlepower limitations of the Federal standard might be exceeded.

In your latest letter, you have enclosed a copy of a test report by Industrial Testing Laboratories and a letter from the California Highway Patrol. You have asked the steps, if any, that Mr. Yost should take to market legally his device. The test repor t is intended to show that maximum candela will not be exceeded when the device is used in a four-lamp headlamp system. California advised that the device appeared legal to install on vehicles equipped with Type F headlamp systems, and that "this system is also permitted by California law as long as the photometric output is within the standards established for any other type of headlight. The ITL tests appear to show compliance".

We have reviewed the ITL test report, and find it indicative of the features and limitations of Mr. Yost's system. The test report shows a failure of the dual filament 2A1 lamp (second column from the left) at test point 4D-V where 3490 candlepower is m easured. Note the maximum limitation of 2500 candlepower at that test point (third column from the right, same line). Contrasted with this is an unusually low reading of 2540 candlepower for the same test point with the single filament 1A1 lamp (third column from the left) when up to 5000 candela is allowed (fourth column from the right). The net result, however, is that the combined maximum of 6030 candlepower (fourth column from the left) is well within the allowable 7500 maximum of Standard No. 10 8 (first column from the right). In essence, the test report indicates that the light at

2 test point 4D-V produced by the system under test does not achieve the balance contemplated by the standard, although the light at other test points meets the requirements of the standard.

While the test report indicates that a system using the lamps tested might conform to Standard No. 108, this was achieved by using what appear to be two lamps of moderate performance. The agency believes it likely that replacement headlamps for such a s ystem would more likely approach the maxima prescribed for 4D-V and other test points for Type 1A1 and 2A1 headlamps with the result that simultaneous operation of upper and lower beams would exceed the established limits. In other words, although an or iginal equipment headlighting system using the relay might meet Federal photometric specifications, there is no assurance that replacement lights would. Type F systems have been designed to preclude exceeding the maxima. Thus, our concern remains for l ighting systems using lamps other than Type F. The agency's views on simultaneous operation are discussed in further detail in a Federal Register notice published in 1986, a copy of which I enclose (Docket No. 81-11; Notice 14).

As I indicated before Mr. Yost's device may be legally installed as original or aftermarket equipment on any passenger car equipped with a Type F headlamp system. Use with any other original equipment headlighting system is expressly prohibited by Stand ard No. 108. As for aftermarket applications other than Type F, he should be aware of the statutory section (15 USC 13979(a)(2)(A)) prohibiting manufacturers, distributors, dealers, and motor vehicle repair businesses from rendering inoperative, in whol e or in part, any equipment installed in accordance with a safety standard if installation of the relay would result in a noncompliance with Standard No. 108.

We are providing a copy of this letter to the California Highway Patrol so that it may be aware of our views on this subject.

Mr. Yost and the agency share a common desire to improve foreground lighting, a subject currently under study at NHTSA. We appreciate his interest in motor vehicle safety.

ENCLOSURE

Sincerely,

ID: nht88-3.100

Open

TYPE: INTERPRETATION-NHTSA

DATE: 09/13/88 EST

FROM: ERIKA Z. JONES -- NHTSA CHIEF COUNSEL

TO: BYUNG M. SOH -- MARKETING DIRECTOR TARGET MARKETING SYSTEMS, INC.

TITLE: NONE

ATTACHMT: ATTACHED TO LETTER DATED 6-20-88 TO NHTSA FROM BYUNG M. SOH, TARGET MARKETING SYSTEMS, INC. OCC-2196

TEXT: This is in reply to your letter of June 20, 1988, with respect to two motor vehicle lighting products which you intend to import into the United States. You have asked "whether these devices require approvals from D.O.T."

First let me explain that the Department of Transportation does not "approve" or "disapprove" specific products. It does advise whether a product appears allowable under the National Traffic and Motor Vehicle Safety Act and the Federal Motor Vehicle Safety Standards.

Your letter does not indicate whether you wish to market these devices as original equipment to be installed before initial sale of a motor vehicle, by either its manufacturer or dealer, or whether you intend to market them solely through the aftermarket. I shall address each situation. The Federal motor vehicle safety standard that applies to original equipment is Standard No. 108 Lamps, Reflective Devices and Associated Equipment. Paragraph S4.1.3 of Standard No. 108 allows additional motor vehicle equipment provided that it does not impair the effectiveness of the lamps and reflectors required as original equipment. Effectiveness may be impaired if the device creates a noncompliance in the existing lighting equipment or 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. In addition, a motor vehicle must remain in conformance with Standard No. 108 (and all other safety standards) until its first purchase for purposes other than resale. There is no Federal standard that applies to your devices as aftermarket equipment, but the National Traffic and Motor Vehicle Safety Act prohibits a manufacturer, distributor, dealer, or motor vehicle repair business from knowingly rendering inoperative, in whole or in part, original lighting equipment.

Your first device is called a "foglight converter." The advertising literature attached states that its function is to turn "the existing

headlights...into foglights...." In our opinion, such a device would create a noncompliance with Standard No. 108 by rendering the headlamp function unavailable when the fog lamp converter is in use. We shall assume that the headlamp would be converted into a fog lamp meeting the specifications of SAE Standard J583 MAY81 Front Fog Lamps. None of the photometric test points of SAE J583 coincide with those specified for headlamps. Our further concern with this device is that a driver might fail to return to the headlamp mode from the fog lamp mode, and operate the vehicle with reduced frontal lighting.

The situation differs with respect to the aftermarket. Under the National Traffic and Motor Vehicle Safety Act, a manufacturer, distributor, dealer, or motor vehicle repair business may not perform modifications that render inoperative, in whole or in part, equipment such as headlamps added pursuant to a Federal safety standard. We believe that the installation of the converter could affect the operability of the headlamp within the meaning of the statutory prohibition. However, we note that the foglight converter is advertised as "easy for any driver to attach to any vehicle." As an owner is not a manufacturer, distributor, dealer, or motor vehicle repair business, the owner is not restricted under Federal law from modifications to his vehicle. He is, however, subject to the laws of the States in which his vehicle is registered and operated. We are not conversant with how State lighting laws might affect use of the foglight converter, and you may wish to obtain an opinion from the American Association of Motor Vehicle Administrators, 4600 Wilson Boulevard, Arlington, VA 22203.

We have several other comments as well. The literature you enclosed depicts the foglight converter attached to what appears to be the European-designed H-4 bulb. Standard No. 108 does not permit headlamps with H-4 light sources to be sold for use on 4-wheeled motor vehicles. In addition, the application of the device where motion is translated from the lamp's exterior to the interior by a linkage in the bulb base would affect compliance with the requirement that the bulb base withstand a pressure differential of 10 psi. Additionally, creating a hole or passage for a linkage has the potential of rendering the headlamp noncompliant with Standard No. 108's requirements for certain environmental tests, such as resistance to dust, corrosion, and humidity.

Your second device is a "headlamp intensity modulator," adjusting a headlamp beam "automatically from low to high beam through a middle beam." According to your literature, when a sensor notes the beams of an oncoming car 500 meters ahead the upper beam gradually passes through a middle beam and diminishes into a lower beam when the vehicles are 150 meters apart. This device is also advertised as capable of owner installation, and without the modification of any vehicle parts. The system appears to operate by a switch. This device directly conflicts with Standard No. 108, and its use would create a noncompliance with it. Headlamps are defined as producing upper and lower beams, and means must be provided for switching between these beams. Use of the device would alter upper and lower beam characteristics from those required by Standard No. 108, and in effect create an infinite number of beams while passing from a conforming upper beam at one extreme to a conforming lower beam at the other. This precludes its use as original equipment. We

believe that its aftermarket legality would be limited. Although Federal law would not preclude an owner from installing it, the instructions are sufficiently complex that in our opinion many purchasers would seek to help from a "dealer" or "motor vehicle repair business," which could not be legally given. There would also remain the question of legality with State laws.

These appear to be innovative devices and we regret that we cannot be more encouraging.

ID: nht88-3.11

Open

TYPE: INTERPRETATION-NHTSA

DATE: 08/19/88

FROM: ERIKA Z. JONES -- CHIEF COUNSEL NHTSA

TO: THOMAS H. JAHNKE -- OASIS INDUSTRIES, INC.

TITLE: NONE

ATTACHMT: LETTER DATED 12/10/87 TO CHIEF COUNCIL--NHTSA FROM THOMAS H. JAHNKE, OCC-1387

TEXT: Dear Mr. Jahnke:

This responds to your letter concerning the application of our regulations and Federal motor vehicle safety standards to your company's planned manufacture of "hardtops" for convertible passenger cars. I regret the delay in responding to your letter. Y ou asked whether any Federal safety standards apply to convertible hardtops; from telephone conversations between your associate Mr. Scaravilli and Ms. Fujita of my staff, we understand that these hardtops are manufactured for sale as aftermarket items o f equipment and that they are designed to be readily removable by the user of the hardtop. Importantly, we assume that the addition of the hardtop to a new vehicle does not change the vehicle from a convertible to a different vehicle type. (The agency has defined a convertible as "a vehicle whose A-pillar (or windshield peripheral support) is not joined at the top with the B-pillar or other rear roof support rearward of the B-pillar by a fixed rigid structural member." Please note that the following i nformation is premised on our assumption that the addition of your hardtop to a convertible does not provide the fixed, rigid structural member in the described location--i.e., we assume that if your hardtop were installed on a new convertible, the vehic le's classification would not be changed to a non-convertible. Indeed, our response would be different if installation of your hardtops on a new convertible changed the classification of the vehicle.)

The answer to your question is yes, there are Federal requirements that apply to your manufacture and sale of the hardtops.

By way of background information, the National Highway Traffic Safety Administration (NHTSA) has the authority under the National Traffic and Motor Vehicle Safety Act (copy enclosed) to establish Federal motor vehicle safety standards for new motor vehic les and items of motor vehicle equipment. NHTSA, however, does not approve motor vehicles or motor vehicle equipment. Instead, the Safety Act establishes a "self-certification" process under which each manufacturer is responsible for certifying that it s products meet all applicable safety standards. This process requires each manufacturer to determine in the exercise of

due care that its products meet all applicable Federal requirements. The agency periodically tests vehicles and equipment items for compliance with the standards, and also investigates other alleged safety-related defects. If you or the agency dete rmines that a noncompliance or safety-related defect exists, you are obligated to notify purchasers of your product and remedy the problem without charge. Manufacturers who fail to provide notification of or remedy for a defect or noncompliance may be s ubject to a civil penalty of up to $1,000 per violation. (A general information sheet describing manufacturers' responsibilities under the Safety Act is enclosed.)

The Safety Act defines the term "motor vehicle equipment" as follows: "Motor vehicle equipment" means any system, part, or component of a motor vehicle as originally manufactured or any similar part or component manufactured or sold for replacement or im provement of such system, part, or component or as any accessory or addition to the motor vehicle ..." (@102(4)) This definition includes the product your company wishes to manufacture since the hardtops are components manufactured and sold either as a r eplacement or improvement of the convertible top or as an addition to vehicles that have no hardtops. Since your product is considered an item of motor vehicle equipment, Oasis as the manufacturer of the equipment must ensure that the hardtops comply wi th all applicable Federal motor vehicle safety standards and contain no safety-related defects.

There are two Federal safety standards that have a direct bearing on the manufacture of your company's hardtops. Safety Standard No. 205, Glazing Materials, sets performance requirements for glazing materials for use in new or used motor vehicles. Glaz ing incorporated in any Oasis hardtop must therefore conform to the applicable specifications set forth in Standard No. 205. The standard establishes both performance requirements, including those regulating the light transmittance and abrasion resistan ce of glazing, and labeling requirements applicable to the glazing used in your product.

The second safety standard having a bearing on your product is No. 302, Flammability of Interior Materials, which establishes flammability requirements for new motor vehicles. The standard specifies that certain components, including convertible tops, of a vehicle which must meet the flammability requirements in order for that vehicle to comply with the standard. However, the effect of Standard No. 302 on your product depends on the circumstances surrounding the installation of the hardtop.

The requirements of Standard No. 302 apply to a vehicle only until its first purchase in good faith for purposes other than resale, and not to aftermarket convertible tops added to a vehicle after the vehicle's first purchase. (This discussion treats th e aforementioned glazing issue as a separate matter and hereinafter assumes that any glazing used in the hardtop conforms to applicable requirements of Standard No. 205.) You are permitted to sell aftermarket convertible tops that do not meet the flammab ility requirements, even if the addition of the hardtop to a vehicle caused the vehicle to no longer comply with Standard No. 302.

However, @108(a)(2)(A) of the Vehicle Safety Act specifies: "No manufacturer, distributor, dealer, or motor vehicle repair business shall knowingly render inoperative ... any device or element of design

installed on or in a motor vehicle or item of motor vehicle equipment in compliance with an applicable Federal motor vehicle safety standard ..." The flammability resistance of the original vehicle is an element of design installed in a motor vehicle in compliance with Standard No. 302. Thus, a manufacturer, distributor, dealer or motor vehicle repair business could not install a convertible hardtop that does not meet the flammability requirements of Standard No. 302 in a new or used motor vehicle since to do so would render inoperative that element of design, and thus violate @108(a)(2)(A) of the Act. Section 109 of the Act specifies a civil penalty of up to $1,000 for each violation of @108.

To summarize the above discussion, Oasis hardtops using glazing must meet applicable requirements of Standard No. 205. Standard No. 302's application to the hardtops depends on the circumstances surrounding installation of the product in new and used mo tor vehicles. If the hardtop meets applicable Federal standards except for Standard No. 302, the hardtop cannot be installed in vehicles by any commercial business listed in @108(a)(2)(A) of the Safety Act. However, those convertible hardtops may legall y be installed in vehicles by the owners of the vehicles. Oasis would still have the responsibility under the Vehicle Safety Act to recall and remedy its products which are determined to contain a defect relating to motor vehicle safety, even if the har dtops were installed by vehicle owners themselves. I note also that NHTSA discourages owners from installing any item of equipment that would degrade the safety performance of their vehicles.

I have enclosed copies of Standard No. 205 and No. 302 for your convenience. In addition, I am enclosing a copy of 49 CFR Part 566, Manufacturer Identification, which applies to all manufacturers of motor vehicles and motor vehicle equipment (except tir es) to which a motor vehicle safety standard applies. This rule requires your company to submit its name, address, and a brief description of the items of equipment it manufacturers to this agency within 30 days after it begins manufacture.

I hope this information is helpful. Please contact my office if we can be of further assistance.

ENCLOSURES

Sincerely,

ID: nht88-3.12

Open

TYPE: INTERPRETATION-NHTSA

DATE: 08/19/88

FROM: ERIKA Z. JONES -- CHIEF COUNSEL NHTSA

TO: JOSEPH P. FAIA --

TITLE: NONE

ATTACHMT: UNDATED LETTER TO ERIKA Z. JONES FROM JOSEPH P FAIA, OCC - 2177

TEXT: This is in reply to your recent undated letter regarding a vehicle lighting accessory for trucks and trailers. It appears from your letter and enclosed diagram that the purpose of the device is to illuminate "two dimensional displays" on the side or rea r of vehicles. A number of such devices would be required, depending on the size of the display to be illuminated. You have not stated the candlepower of the device. Reference is made to a transparent section through which the light is emitted, and to a "semi-translucent" section which is "tinted and arranged to function as the running lights commonly seen on trailers." The color of the light is not specified, but we shall assume that it is amber or red when emitted through the "semi-translucent" sec tions, and white when emitted through the transparent sections to illustrate the display.

You have asked four questions with regard to this device. The first question is whether it can be used as a "combination side illumination and marker light." As a general rule, supplementary lighting devices such as yours are permissible as original equ ipment if they do not impair the effectiveness of lamps, reflective devices, and associated equipment required by Federal Motor Vehicle Safety Standard No. 108. They are permissible as aftermarket equipment under Federal law if their installation by a p erson other than the vehicle owner does not "render inoperative in whole or in part" lighting equipment installed in accordance with Standard No. 108, but their legality is otherwise determined by the laws of the States in which the vehicle is registered and operated. As for whether your device may be used as a combination side illumination and marker light, if you mean as the only side marker lamp, the combination per se is not prohibited by Standard No. 108. However, the side marker lamp in such a c ombination must comply with photometric, location, color, and other requirements for such lamps, and its effectiveness must not be impaired. One example of impairment would be if the glare from the device's white light masked the conspicuity of the side marker. As a combined device supplementing the required side marker lamp, it is permissible if it does not impair the effectiveness of

the required side marker. For purposes of this letter and with respect to Standard No. 108 we equate "impairment of effectiveness" with "partial inoperative."

Your second question is whether it can be used "as a backup light and parking light, to be used only in these situations." It is unclear whether you intend the device to be the backup lamp required by the standard, or one that supplements it. If the for mer, its use is permissible provided that the backup function meets all requirements of Standard No. 108 that are specified for backup lamps, such as color and photometrics, and provided that the display function does not impair the effectiveness of the backup function. Because the color of light in both functions would be identical, care must be taken to ensure that the backup signal is clearly perceived. If you intend it as a supplementary backup lamp, it is permissible as long as it does not impair the effectiveness of the primary backup lamp. Your term "parking light" is unclear; because front parking lamps are not required on vehicles whose overall width is 80 inches or more, I assume you mean a lamp on the rear of a vehicle that is not a backu p lamp but which can be used to indicate that the vehicle is moving slowly while being parked. The device appears permissible as long as it does not impair the effectiveness of the other lighting equipment on the rear.

Your third question is whether the device may be used as a stop lamp, activated only when the brake is applied. Two devices may be used as the original equipment stop lamps, provided all requirements of Standard No. 108 are met and that the display func tion does not impair the effectiveness of any other lighting equipment. One or more devices could be used as supplementary stop lamps under the same restriction.

Your final question is whether it may be used alone as a display light. The answer is yes, subject to the impairment prohibition. The only specifically prohibited use of the lamp is its combination with a clearance lamp, a configuration which appears d epicted by the uppermost lights, front and rear, of your Figures 2 and 3.

I hope that this answers your question.

Sincerely,

ID: nht88-3.13

Open

TYPE: INTERPRETATION-NHTSA

DATE: 08/19/88

FROM: RANDY BLACKMAN -- PER LUX INC

TO: NHTSA

TITLE: NONE

ATTACHMT: ATTACHED TO LETTER DATED 08/07/89 FROM STEPHEN P. WOOD -- NHTSA TO RANDY BLACKMAN; REDBOOK A34 [4]; STANDARD 202; STANDARD 302

TEXT: Dear Sir or Madam:

Per-Lux is a manufacture of automotive driving and safety lights and other automotive products. An inventor has proposed to us the possibility of manufacturing and distributing a head restraint device for pick-up trucks.

Will you please advise me which, if any, Federal Safety standards would directly or indirectly apply to this product.

I have enclosed a sketch of the proposed product for your information.

Sincerely,

ID: nht88-3.14

Open

TYPE: INTERPRETATION-NHTSA

DATE: 08/24/88

FROM: JOSEPH L. CIAMPA

TO: BEVERLY B. BYRON

TITLE: NONE

ATTACHMT: ATTACHED TO LETTER DATED 10/27/88 FROM ERIKA Z JONES TO BEVERLY B BYRON; REDBOOK A32, STANDARD 205; MEMORANDUM DATED 08/14/85 FROM C. RICHARD FRAVEL TO WHOM IT MAY CONCERN RE JOSEPH CIAMPA JR.; MEMORANDUM DATED 08/04.88 FROM ARTHUR J LOMART TO WHOM IT MAY CONCERN; LETTER DATED 08/01/88 FROM C. E. SHUE TO JOSEPH CIAMPH JR RE 0590630; LETTER DATED 09/12/88 FROM NANCY F MILLER TO BEVERLY B BYRON; LETTER DATED 08/25/88 FROM BEVERLY B BYRON T. NANCY MILLER

TEXT: Dear Congress Woman Byron:

The purpose of this letter is to ask your help with a problem I am having with the State of Maryland dealing with a federal regulation.

This has to do with tinted windows I have on my car (side windows only), since 1985 due to an exemption that I was granted by the State of Maryland for medical reasons. I have Diabetes and eyes sensiative to sunlight.

I am now being told by the State of Maryland that the Federal Government will not allow them to grant any more medical exemptions and that there is no recourse for appeal in this matter. I find this very difficult to understand when we are all talking a bout the plight of the handicapped. In my own way, this is causing me to have a problem by having severe headaches on a daily basis caused by bright sunlight. I consider this very much of a handicap over other people who do not suffer from this problem or with the disease of Diabetes.

Your help in getting medical exemptions restored to Maryland for myself and others with the same problems is greatly needed and will be appreciated. I feel to date that I have been talking to to uncaring ears regarding this matter.

Even though I am not a crusader, if I must I will start a campaine of letter writing and petitions because I feel this is being handled so unjustly.

Again, thank you for your immediate help in this matter because I have already had my automobile tags on one car suspended while pursuing this matter.

ID: nht88-3.15

Open

TYPE: INTERPRETATION-NHTSA

DATE: 08/25/88

FROM: BEVERLY B. BYRON -- MEMBER OF CONGRESS

TO: NANCY MILLER, -- OFFICE OF CONGRESSIONAL AFFAIRS UNITED STATES DEPARTMENT OF TRANSPORTATION

TITLE: NONE

ATTACHMT: ATTACHED TO LETTER DATED 10/27/88 FROM ERIKA Z JONES TO BEVERLY B BYRON; REDBOOK A32, STANDARD 205 MEMORANDUM DATED 08/14/85 FROM C. RICHARD FRAVEL TO WHOM IT MAY CONCERN RE JOSEPH CIAMPA JR.; MEMORANDUM DATED 08/04/88 FROM ARTHUR J LOMART TO W HOM IT MAY CONCERN; LETTER DATED 08/01/88 FROM C. E. SHUE TO JOSEPH CIAMPA JR RE 0590630; LETTER DATED 09/12/88 FROM NANCY F MILLER TO BEVERLY B BYRON; LETTER DATED 08/24/88 FROM JOSEPH L. CIAMPA TO BEVERLY B. BYRON

TEXT: Dear Ms. Miller:

I have enclosed correspondence received from Mr. Joseph L. Ciampa, Jr. of 4855 Cherry Tree Lane, Sykesville, Maryland 21784 concerning a number of questions he has with regard to tinted automobile windows.

I would very much appreciate your assistance in reviewing those concerns which Mr. Ciampa has raised and providing me with appropriate information in order that I may properly respond.

ENCLOSURE

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.