ID: 22843

Mr. Matz Larsson
Sales Manager
Broderna Holmbergs Fabriks AB
Box 63
SE-334 21 Anderstorp
Sweden





Dear Mr. Larsson:

This is in response to your letter of March 7, 2001, asking whether the buckle release on your child restraint system meets the area requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 213, "Child Restraint Systems." The answer is yes.

S5.4.3.5(c) of Standard No. 213 requires any buckle in a child restraint system to "[m]eet the requirements of S4.3(d)(2) of FMVSS No. 209," which reads:

A buckle designed for pushbutton application of buckle release force shall have a minimum of 452 mm with a minimum linear dimension of 10 mm for applying the release force, or a buckle designed for lever application of buckle release force shall permit the insertion of a cylinder 10 mm in diameter and 38 mm in length to at least the midpoint of the cylinder along the cylinder's entire length in the actuation portion of the buckle release. A buckle having other design for release shall have adequate access for two or more fingers to actuate release.

Since your buckle requires a sliding action to activate the buckle release, we consider your buckle release to be designed for slide application rather than pushbutton or lever application. Thus, your buckle release falls under the "other design for release" category.

Under the last sentence of S4.3(d)(2), a buckle having other design for release must have adequate access for two or more fingers to actuate release. You claim that your buckle release meets this requirement. We agree. All of our staff working on this response were able to place two fingers into your slide action release button to actuate release. Thus, we have determined that your buckle release meets the requirement of S4.3(d)(2).

If you have any further questions, please feel free to contact Mr. Dion Casey of this office at (202) 366-2992.

Sincerely,

John Womack
Acting Chief Counsel
ref:213#209
d.4/10/01

ID: 2284y

Mr. Diana L.D. Regan
43 Rockwood Drive
Larchmont, NY 10538

Dear Ms. Regan:

This responds to your letter seeking an interpretation of how our laws and regulations would apply to a product you have invented. Your product is designed to alter the alignment of the webbing of a lap/shoulder safety belt to improve the fit of the safety belt on children weighing between 40 and 85 pounds. According to your letter, the product is designed to be firmly attached to the webbing of both the lap belt portion and the shoulder belt portion of the safety belt. When the product is attached, it pulls down the shoulder belt portion of the safety belt so that it will pass across the child's chest and shoulder, instead of the neck. You asked whether this product would be considered a safety belt or a child restraint system for the purposes of our safety standards. The answer is that your product would not be considered to be either for the purposes of our standards, as explained below.

Section S3 of Standard No. 209, Seat Belt Assemblies (49 CFR 571.209) defines a "seat belt assembly" as "any strap, webbing, or similar device designed to secure a person in a motor vehicle in order to mitigate the results of any accident, including all necessary buckles and other fasteners, and all hardware designed for installing such seat belt assembly in a motor vehicle." (Emphasis added). Your device is not itself designed to secure a child in a motor vehicle. Instead, your device is designed to alter the alignment of the existing safety belt in the vehicle, so that the existing safety belt system in the vehicle can be adjusted to better fit a child occupant. Therefore, your device would not be a "seat belt assembly" within the meaning of Standard No. 209.

Section S4 of Standard No. 213 (49 CFR 571.213) defines a "child restraint system" as "any device except Type I or Type II seat belts, designed for use in a motor vehicle or aircraft to restrain, seat, or position children who weigh 50 pounds or less." (Emphasis added). As explained above, your device is not a Type I or Type II seat belt. Additionally, for the reasons explained above, your device is not itself designed to restrain, seat, or position children. The restraining of the child would be accomplished entirely by the safety belt system already installed in the vehicle. Your device would simply alter the alignment of that safety belt system for the child. Therefore, your device would not be a "child restraint system" within the meaning of Standard No. 213.

You also asked for information regarding your responsibilities as the manufacturer and seller of this product. I have enclosed an information sheet we have prepared for new manufacturers of motor vehicle equipment. I have also enclosed copies of a February 11, 1988 letter to Mr. Roderick A. Boutin and a November 22, 1988 letter to Ms. Claire Haven. These two letters describe how products intended to enhance the comfort of safety belt wearers could be affected by our laws and regulations. The information sheet explains how to obtain copies of our laws and regulations. I hope this information is helpful.

Sincerely,

Stephen P. Wood Acting Chief Counsel

Enclosures

/ref:208#209#213 d:2/l4/90

ID: 22851ogm

Ms. Shannon Dunn
Lorensen Toyota
P.O. Box 427
Old Saybrook, CT 06475





Dear Ms. Dunn:

This responds to your letter requesting information regarding modification of a 2001 Toyota Avalon for a passenger with a urologic condition. Your letter, which was accompanied by a letter from the vehicle owner's physician, indicates that the owner is unable to wear a seat belt due to the aforementioned disability. You request permission to remove or disable a warning light that illuminates whenever the front passenger seat is occupied while the seat belt for that seating position remains unfastened.

I would like to begin by explaining that the National Highway Traffic Safety Administration is authorized to issue Federal motor vehicle safety standards that set performance requirements for new motor vehicles and items of motor vehicle equipment. Manufacturers are required to certify that their products conform to our safety standards before they can be offered for sale. After the first sale of the vehicle, manufacturers, distributors, dealers, and repair businesses are prohibited from "knowingly making inoperative" any device or element of design installed on or in a motor vehicle in compliance with an applicable standard. In general, the "make inoperative" prohibition (49 U.S.C. 30122) requires businesses that modify motor vehicles to ensure that they do not remove, disconnect, or degrade the performance of safety equipment installed in compliance with an applicable standard. Violations of this prohibition are punishable by civil penalties of up to $5,000 per violation.

Standard No. 208, Occupant Crash Protection, requires vehicles to be equipped with specific manual and automatic restraint systems (e.g. seat belts and air bags) and to meet specified injury criteria during a test. Paragraph S7.3 of Standard No. 208 requires a seat belt warning system with a warning light and an audible signal to warn when the driver's lap belt is not fastened. However, S7.3 applies only to the driver's seating position and does not apply to the passenger seating position.

The seat belt warning light for the passenger seating position is not required by Standard No. 208 or any other Federal motor vehicle safety standard. Accordingly, a manufacturer, distributor, dealer or repair business would be able to disable or remove the passenger seatbelt warning light described in your letter without violating Federal law. However, such a business could not disable the warning light applicable to the driver's seating position.

If you have other questions or require additional information, please contact Otto Matheke of my staff at this address or by phone at (202) 366-2992.

Sincerely,

John Womack
Acting Chief Counsel

ref:VSA
d.6/1/01

ID: 2285y

Mr. Victor Crisci
70 Lenox Road
Wayne, NJ 07470

Dear Mr. Crisci:

This is in response to the telephone call you made to me after receiving the interpretation of Motor Vehicle Safety Standard No. l08 furnished you on August 7, l989.

To summarize, you wished to know whether a "safety light flasher" to be installed on your motorcycle would conflict with DOT regulations. This device flashes a motorcycle headlamp between upper and lower beam for 2 to 4 seconds, then returns the light to the beam it was in when the flasher was activated. If the headlamp is off, the flasher will turn it on and initiate an identical flash cycle. We advised you that Standard No. l08 allowed flashing headlamps only on vehicles equipped with turn signals (S5.5.10(c)), and that the provision applicable to motorcycle headlamps (S5.5.l0(d)) permitted only headlamp modulators, which must provide varying intensities within a single beam, and not between beams.

You have questioned this interpretation because motorcycles are required to be equipped with turn signals. We have reviewed Standard No. l08, and have concluded that your device is prohibited, albeit for reasons other than section S5.5.10(c). Section S5.5.1 requires that the means for switching between upper and lower beams conform to one of two SAE Recommended Practices, either J564a, or J565b. The first requires that the switch be operated by a simple movement of the driver's hand or foot. We do not interpret this as allowing automatic switching between upper and lower beams. Although the second provides for automatic switching, it is in the context of changing the upper beam to the lower one when oncoming traffic is approaching. Your device does not contain this feature.

We must also bring your attention to section S5.1.3. This section prohibits the installation of supplementary lighting devices if they impair the effectiveness of lighting equipment that is required by Standard No. l08. In our opinion, a device that switches between upper and lower beam at times when the headlamp is illuminated would impair the roadway illumination that the headlamp is intended to supply. In addition, if the flasher caused lamps other than the headlamp to flash (such as the taillamp, which must be activated when the headlamp is steady-burning), that are required to be steady-burning in use, a noncompliance with section S5.5.11(e) would result.

Sincerely,

Stephen P. Wood Acting Chief Counsel

/ref:l08 d: 2/l4/90

ID: 22874.ztv

Mr. Markus Evans
PMA-Racine
Racine Operations
1733 90^th Street
Sturtevant, WI 53177





Dear Mr. Evers:

This is in reply to your fax of March 13, 2001, to Dave Coleman of this agency asking for an interpretation regarding whether it is necessary for a certain product to comply with Federal Motor Vehicle Safety Standard No. 121, Air Brake Systems.

You state that Putzmeister is "one of the world's largest manufacturer of truck-mounted concrete pumps." You ask whether a contemplated model would need to be equipped with an anti-lock braking system (ABS), or "can it be regarded as construction equipment without need to be equipped with ABS?"

Your question indicates that you are familiar with the long-standing interpretations of this agency that mobile construction equipment vehicles are not motor vehicles which must comply with the Federal motor vehicle safety standards. We are currently reviewing our position in this matter. I enclose a copy of a letter that we sent on March 21, 2001, to the Colorado State Patrol, as the latest expression of our opinion.

In brief, our interpretations have been in compliance with a Federal District Court decision of 1978. We are now concerned that mobile construction equipment may be using the public roads with greater frequency than the equipment that the Court decided were not motor vehicles subject to our jurisdiction. A later Supreme Court decision may provide us with a basis for deciding that mobile construction vehicles are, in fact, motor vehicles. If we decide that they are motor vehicles, your planned product might have to be manufactured with ABS and to comply with all other relevant Federal motor vehicle safety standards as well.

However, we have not yet undertaken the analysis needed to address the issue. This means that your planned product need not be equipped with ABS. In the event that we decide that mobile construction equipment vehicles are motor vehicles, we will announce it publicly, and would establish an effective date that will accommodate the realities of manufacturing mobile construction equipment.

If you have any questions, you may call Taylor Vinson of this Office.

Sincerely,

John Womack
Acting Chief Counsel

Enclosure
ref:571
d.4/19/01

ID: 22892twobarsfromonerod

Mr. Chris Tinto
Director, Technical & Regulatory Affairs
Toyota Motor North America, Inc.
Washington Office
1850 M Street, NW, Suite 600
Washington, DC 20036





Dear Mr. Tinto:

This responds to your March 19, 2001, letter concerning Federal Motor Vehicle Safety Standard No. 225, "Child Restraint Anchorage Systems" (49 CFR '571.225). The standard requires the installation of child restraint anchorage systems consisting of two lower anchorages and a top tether anchorage. You ask about the configuration requirements specified in S9.1 for the lower anchorages.

Toyota would like to form the two lower anchorages by bending two bar segments from a long, continuous 6 millimeter (mm) diameter rod. According to the diagram you attached to your letter, each bar segment to which a child restraint would latch onto is approximately 35 mm long and parallel to the main portion of the rod. The rod is bent such that the bar segments protrude about 67 mm (about 2.5 inches) from the rest of the rod. You ask if forming the two lower anchorages from one continuous piece of rod would be permitted if the anchorages were so configured.

Our answer is yes, the bar segments are permitted to be configured as you described.

S9.1.1 of Standard No. 225 specifies that "[t]he lower anchorages shall consist of two bars that . . .  [a]re not more than 40 mm in length . . . ." ⁽¹⁾  Your question raises the issue of whether your anchorages consist of two bars. The bars are formed from one continuous rod. However, because the bars protrude 67 mm from the main portion of the rod and the part of the rod between the two bars would be in the seat bight and not visible to the consumer, two distinct bars are presented to consumers. A consumer is not likely to be confused about where a child restraint should be attached. We thus conclude that the lower anchorages consist of two bars, each of which is not more than 40 mm in length. We could have concluded otherwise had the bars not protruded 67 mm (or some other substantial distance) from the rest of the rod. For example, if they protruded only 10 mm from the rest of the rod, it would not be apparent that two bars are present. An anchorage system with such a design would not meet S9.1.1 of the standard.

I hope this information is helpful. If you have further questions, please contact Deirdre Fujita of my staff at (202) 3366-2992.

Sincerely,

John Womack
Acting Chief Counsel

Ref:225
d.7/30/01






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1. ¹ The agency has received petitions for reconsideration asking that the maximum limit ofm 40 mm be deleted or increased to 50 mm. See Docket No. 98-3390, Notice 2. NHTSA will be responding to the petitions in the near future.

ID: 22894.ztv

Mr. Tadashi Suzuki
Manager, Regulation & Homologation
Stanley Electric Co., Ltd.
2-9-13, Nakameguro, Meguro-ku
Tokyo 153-8636
Japan





Dear Mr. Suzuki:

This is in reply to your letter of March 12, 2001, asking for an interpretation of S7.8.5 of Federal Motor Vehicle Safety Standard No. 108.

S7.8.5 specifies that "When activated in a steady-burning state, headlamps shall not have any styling ornament or other feature, such as a translucent cover or grill, in front of the lens." This prohibition was developed when the only headlamps available were sealed beam units. You state that the majority of headlamps today are individually designed for specific vehicles and you believe that the performance of these headlamps can be controlled so that if they have additional parts, the headlamp designer has complete control over them. Therefore "banning of styling parts for all kinds of headlamps has no meaning to safety." For this reason, you "believe S7.8.5 is not applicable to headlamps designed for specific vehicle models."

We do not agree with your interpretation. S7.8.5 contains no qualifying language; it applies to all headlamps. However, S7.8.5 does not prohibit use of a "styling ornament or other feature" in the lens itself, or behind the lens, if the headlamp with these features is certified as complying with Standard No. 108.

We also call your attention to S5.1.3 which, in effect, prohibits additional motor vehicle equipment that impairs the effectiveness of lighting equipment required by Standard No. 108. Any styling feature or other part of a motor vehicle that is in front of the lens of a headlamp in use has the potential to impair the light output of the lamp. Even if there is no impairment initially, grills and covers prevent the lamps from being cleaned. Covers themselves are susceptible to accumulations of dirt and moisture on their inner surface. These accumulations on the outer surface of the headlamp lens can cause glare and reduction in roadway illumination

(S5.1.3 would also prohibit, as original equipment, covers over required lighting equipment other than headlamps, for the same reason of impairment). While our laws do not prohibit the sale of lamp covers in the aftermarket, their installation would create a noncompliance with Standard No. 108. In that instance, there would be a violation of 49 U.S.C. 30122(b) if the covers were installed by a manufacturer, dealer, distributor, or motor vehicle repair business.

Sincerely,

John Womack
Acting Chief Counsel

ref:108
d.5/9/01

ID: 22898ogm

Mr. Ray Metzger
KayRay Products
P.O. Box 6787
Spring Hill, FL 34611





Dear Mr. Metzger:

This responds to your letter concerning a device your company manufactures known as the "Relax-A-Strap." As indicated by the sample of the device enclosed with your letter, the "Relax-A-Strap" is intended to slide over the shoulder portion of a lap and shoulder seat belt and position this portion of the belt so it does not contact the neck or collarbone of vehicle occupants. According to the instructions accompanying the device, the "Relax-A-Strap" allows an occupant to position the shoulder belt in the manner they desire and then use the device to prevent the belt from being retracted against their body. You request that the agency advise you as to whether the "Relax-A-Strap is safe "for the general consumer to use as per instructions and illustrations."

The National Highway Traffic Safety Administration (NHTSA) has the authority to issue Federal motor vehicle safety standards for new motor vehicles and new items of motor vehicle equipment. The agency does not approve, certify or endorse any vehicles or equipment. Instead, manufacturers are required to certify that their vehicles and equipment meet all applicable standards. The following represents our opinion based on the facts provided in your letter.

The agency cannot provide you with the opinion that you seek. There is currently no Federal motor vehicle safety standard that would apply to your product (FMVSS). We do have a standard (FMVSS No. 209, Seat belt assemblies) that sets forth requirements for new seat belt assemblies. However, since your product would not be installed as part of a new seat belt assembly, the standard would not apply.

Your product is apparently intended to restrict the operation of the retractor attached to the shoulder portion of a Type II seat belt and allow the shoulder belt to move away from the neck and shoulder of the occupant. It functions as a seat belt positioner. At this time, NHTSA does not have a standard or regulation for seat belt positioners. However, in a notice of proposed rulemaking (NPRM) published in the Federal Register on August 13, 1999 (64 FR 44164)(copy enclosed), we proposed to adopt a consumer information regulation for seat belt positioners. In the NPRM, we proposed to define "seat belt positioner" as "a device, other than a belt-positioning seat, that is manufactured to alter the positioning of Type I and/or Type II belt systems in motor vehicles." Among other things, the NPRM proposed to require the devices to be labeled as not suitable for children of a certain age, e.g., under 6 years old, or a certain height.

It appears that the Relax-A-Strap would be considered a seat belt positioner under the proposed definition. Assuming we issue a final rule adopting a consumer information regulation, the rule's definition of "seat belt positioner" could be the same as the definition in the NPRM or a logical outgrowth of the proposed definition. We anticipate issuing a final decision on the NPRM in the near future.

While no FMVSS currently applies to your product, your device is considered to be an item of motor vehicle equipment. As a manufacturer of motor vehicle equipment, you are subject to the requirements of 49 U.S.C. 30118-30121 concerning the recall and remedy of products with safety related defects. I have enclosed an information sheet that briefly describes those and other manufacturer responsibilities. In the event you or NHTSA determines that your product contains a safety-related defect, you would be responsible for notifying purchasers of the defective equipment and remedying the problem free of charge. We encourage you to undertake a complete evaluation of your product to determine if its use would degrade the performance of safety belts.

In addition, manufacturers, distributors, dealers, and motor vehicle repair businesses are subject to 49 U.S.C. section 30122, which prohibits them from installing the device if the installation "makes inoperative" the vehicle's compliance with any safety standard. It appears unlikely from the nature of your product that it would be placed in vehicles by commercial businesses instead of consumers. However, if your product were to be installed by a commercial business, it must ensure that its installation does not compromise the safety protection provided by the vehicle belt system. The prohibition of section 30122 does not apply to the actions of vehicle owners in adding to or otherwise modifying their vehicles or items of motor vehicle equipment.

I hope this information has been helpful. If you have any other questions, please contact Otto Matheke of my staff at this address or by phone at (202) 366-5253.

Sincerely,

John Womack
Acting Chief Counsel

Enclosure
ref:208
d.9/13/01

ID: 22915.rbm

Mr. Jurgen Babirad
Rehabilitation Technology Associates, Inc
P.O. Box 540
Kinderhook, NY 12106





Dear Mr. Babirad:

This responds to your correspondence regarding the National Highway Traffic Safety Administration's (NHTSA) final rule on vehicle modifications for individuals with disabilities. You ask about the applicability of that rule to a conversion that requires a lowered floor and the installation of a power transfer seat, mechanical hand controls, a steering spinner, an automatic wheelchair lift, and a power door opener. You are concerned that such a conversion may affect the vehicle's compliance with FMVSS No. 105, Hydraulic and electric brake systems, FMVSS No. 206, Door locks and door retention components, FMVSS No. 208, Occupant crash protection, and FMVSS No. 301, Fuel system integrity.

By way of background, NHTSA administers a statute requiring that motor vehicles manufactured for sale in the United States or imported into the United States be manufactured so as to reduce the likelihood of motor vehicle crashes and of deaths and injuries when crashes do occur. That statute is the National Traffic and Motor Vehicle Safety Act of 1966 ("Vehicle Safety Act") (49 U.S.C. '' 30101, et seq.).

One of the agency's most important functions under that Act is to issue and enforce the Federal Motor Vehicle Safety Standards (FMVSSs). These standards specify safety performance requirements for motor vehicles and/or items of motor vehicle equipment. Manufacturers of motor vehicles must certify compliance with all applicable safety standards and permanently apply a label to each vehicle stating that the vehicle complies with all applicable FMVSSs.

The Vehicle Safety Act also prohibits manufacturers, distributors, dealers, or motor vehicle repair businesses from knowingly making inoperative any part of a device or element of design installed on or in a motor vehicle or motor vehicle equipment that is in compliance with any applicable FMVSS (49 U.S.C. 30122). If NHTSA determines that a business has violated the make inoperative provision, it may assess a civil penalty in the amount of $5,000 per violation (not to exceed $15,000,000 in the aggregate). NHTSA may, through regulation, exempt a person or business from the prohibition if it decides that an exemption is consistent with motor vehicle safety and the Vehicle Safety Act.

On February 27, 2001, NHTSA published a final rule setting forth a limited exemption from the make inoperative prohibition for businesses or individuals who modify vehicles for persons with disabilities (66 Federal Register 12638; Docket No. NHTSA-01-8667). The exception, codified at 49 CFR Part 595, was limited to modifications made after the first retail sale of the vehicle. Accordingly, it does not apply to vehicle manufacturers or alterers. Vehicle modifiers, i.e., businesses that modify a vehicle after first retail sale, may not modify a vehicle in such a way as to negate the vehicle's compliance with any applicable FMVSSs for which there is no exemption, although the modifier is not required to certify compliance with all applicable standards.

While portions of several FMVSSs, including FMVSS No. 208, are included in the Part 595 exemption, FMVSS No. 105, FMVSS No. 206, and FMVSS No. 301 are not. I note however that, by its terms, FMVSS No. 206 does not apply to vehicle doors that are equipped with a wheelchair lift as long as the lift system has either an audible alarm or a visual alarm that can be seen by the driver of the vehicle.

Because there is no exemption related to fuel systems, or to hydraulic or electric brake systems, ⁽¹⁾ vehicle modifiers must take care to ensure that they do not modify the fuel and brake systems in a manner that takes the vehicle out of compliance with FMVSS No. 301 or FMVSS No. 105. The surest way to do so would be to purchase vehicles in which any needed changes were already made by the vehicle manufacturer or alterer, who has certified compliance with FMVSS No. 105 and FMVSS No. 301. Another way would be to modify the vehicle pursuant to a specific protocol based on analysis of compliance testing in accordance with those two standards. For example, we believe that the National Mobility Equipment Dealers Association (NMEDA) has successfully crash-tested a vehicle with a lowered floor and that it provides an explanation of how to make such a modification without compromising compliance with the FMVSS to its Quality Assurance Program (QAP) members. Although it might be possible for a modifier to use engineering analysis alone to determine whether a modification would take a vehicle out of compliance with the standards, this option is risky since there would be no compliance test data to verify the soundness of the modifier's judgment.

As noted above, portions of FMVSS No. 208 are included in the Part 595 exemption from the make inoperative provision. Specifically, those portions of FMVSS No. 208 that require an air bag (S4.1.5(a)(1), S4.1.5.1(a)(3), S4.2.6.2, and S5) or address seat belt adjustment (S7.1), seat belt latch assembly (S7.2), or seat belt comfort and convenience (S7.4) are included in the exemption as long as the affected seating position has a Type 2 or Type 2A seat belt that meets the requirements of 49 CFR 571.209 and 49 CFR 571.210.

NHTSA cannot provide information as to whether the types of potential modifications you have discussed would have the effect of taking the vehicle out of compliance with any of the safety standards addressed in this letter or whether they would fall within the exemption in 49 CFR Part 595. That responsibility lies with the modifier. Accordingly, we urge vehicle modifiers to work closely with the vehicle manufacturers to determine whether a potential modification would take a vehicle out of compliance and to ensure that a modification that is subject to the Part 595 exemption is done consistent with the exemption.

I hope the addresses your concerns. Please contact Rebecca MacPherson of my staff at this address or at (202) 366-2992 should you have any additional questions about this matter.

Sincerely,

John Womack
Acting Chief Counsel

ref:595
d.12/14/01





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¹ Part 595 does include an exemption from the requirement in FMVSS No. 135 that the brake be pedal-operated.

ID: 22938.ztv.wps

Mr. Tadashi Suzuki
Manager, Regulation & Homologation
Stanley Electric Co., Ltd.
2-9-13, Nakameguro, Meguro-ku
Tokyo 153-8636
Japan





Dear Mr. Suzuki:

This is in reply to your letter of March 22, 2001, asking for an interpretation of "the photometric ratio requirement of tail lamp and stop lamp" of Federal Motor Vehicle Safety Standard No. 108.

Standard No. 108 incorporates by reference SAE Standard J586 FEB84, Stop Lamps for Use on Motor Vehicles Less Than 2032 MM in Overall Width. You seek our advice on "limiting the compartments to be lit of both tail lamp and stop lamp when computing the photometric ratio of various types of arrangement." You have enclosed a drawing that shows several examples of lamp arrangements.

Example 1 depicts a two-compartment design, one a stop lamp, the other a taillamp. The distance between the filament centers of the light sources in the two compartments is 200 mm. You ask whether the photometric ratio should be applied in this case.

As you wrote, paragraph 5.1.5.3 of SAE J586 states, in pertinent part, "If a multiple compartment . . . arrangement is used and the distance between optical axis for both the tail lamp and stop lamp is within the dimensions specified in paragraph 5.1.5.2, the ratio of the stop lamp to the tail lamp shall be computed with all the compartments . . . lighted." The distance between adjacent light sources specified in 5.1.5.2 for a multiple compartment lamp is 560 mm or less. In your Example 1, the distance is 200 mm. Therefore, the ratio of the stop lamp to the taillamp in your Example 1 must be computed with both compartments lighted.

Example 2 also depicts a two compartment lamp, one of which serves as a taillamp and the other, both a taillamp and a stop lamp function. The distance between the filament centers of the light sources in the two compartments is 200 mm. You ask whether both compartments should be included "when applying the ratio requirement."

The answer is yes. Because one of the taillamps is combined with the stop lamp in the same compartment, as you note, paragraph 5.1.5.3 first establishes a ratio that must be met by the dual-

purpose light source in that compartment. Then, because the adjacent compartment also serves as a taillamp, and the distance between the optical centers of the two light sources is 200 mm, the ratio of the stop lamp to the taillamp in the adjacent compartment must be computed with both compartments lighted.

Example 3 depicts a three-compartment lamp. The first two compartments are taillamps and the filament centers of the light sources are 200 mm apart. The third compartment is the stop lamp; the filament center of its light source is 250 mm from that of the light source in the adjacent taillamp compartment. You ask whether the ratio requirement should be satisfied. If so, "what compartment should we use? All of the three compartments, or [only the stop lamp and adjacent taillamp compartments]?"

You should use all three compartments in satisfying the ratio requirement. Paragraph 5.1.5.2 does not apply the ratio requirement in a multiple compartment lamp if "the distance between adjacent light sources does not exceed . . .410 mm for three compartments." Although the distance between the light sources in the first and third compartments is 450 mm, the distance between the first and second adjacent light sources is only 200 mm, and the distance between the second and third adjacent light sources is only 250 mm. Therefore, the ratio still applies.

I hope that this answers your questions.

Sincerely,

John Womack
Acting Chief Counsel

ref:108
d.5/3/01