Interpretation ID: 1983-3.12

TYPE: INTERPRETATION-NHTSA

DATE: 10/20/83

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: BMW of North America, Inc.

TITLE: FMVSS INTERPRETATON

TEXT:

NOA-30

Mr. Karl-Heinz Ziwica, Manager Safety & Emission Control Engineering BMW of North America, Inc. Montvale, New Jersey 07645

Dear Mr. Ziwica:

This is in reply to your letter of August 4, 1983, to Mr. Vinson of this office asking for a reconsideration of our December 8, 19B2, letter in which we stated that Motor Vehicle Safety Standard No. 108 prohibits the use of glass or plastic shields in front of motorcycle headlamps. You have pointed out that this appears to reverse a previous interpretation issued by this office on March 15, 1978, in which we concluded that such covers were not precluded.

As is well known, SAE Standard J580 Sealed Beam Headlamp Assembly precludes the use of covers in front of headlamps in use. Because Standard No. 108 allows installation on motorcycles of half of a passenger car sealed beam headlighting system (principally because SAE J584 allows use of headlamps meeting SAE J579 Sealed Beam Headlamp Units), the 1982 interpretation applied the prohibition against covers to all sealed beam headlamps, even those used on motorcycles. With respect to unsealed lamps, the agency cited paragraph S4.1.3, the prohibition against installation of additional equipment impairing the effectiveness of required lighting equipment, and concluded that the possibility of deterioration of light output through cracked or discolored covers precluded covers over nonsealed lamps. On the other hand, the 1978 interpretation concluded that, since the cross referenced J579 did not itself reference J580, the prohibition did not apply.

We have reviewed this matter and have concluded that headlamp covers for motorcycles are not per se prohibited by Standard No. 108. As the 1978 interpretation implies, and as you make explicit, the only standard Table III directly incorporates for motorcycle headlamps is J584, whereas J580 is one of several standards directly incorporated for headlamps on four-wheeled vehicles. Nevertheless, we still conclude that these covers are prohibited if they impair the effectiveness of the headlamp.

If, for example, the angle of the cover is so extreme that headlamp "effectiveness" is "impaired" because of deterioration of the beam, then the manufacturer may wish to remove the shield or redesign it. If, as another example, a plastic cover is intended and a manufacturer has knowledge that it is susceptible to accelerated hazing or cracking, the manufacturer should not use a cover manufactured of this plastic.

In summary, this letter modifies both our 1978 and 1982 opinions by concluding that headlamp covers for motorcycles are permissible if they will not impair the effectiveness of the headlamp.

The agency is reviewing this subject to determine if rulemaking is advisable to prohibit covers of any sort over motorcycle headlamps, similar to the prohibition against such covers on four-wheeled motor vehicles.

Sincerely,

Frank Berndt Chief Counsel

August 4, 1983

Mr. Z. Taylor Vinson, Esq. National Highway Traffic Safety Administration U.S. Department of Transportation 400 Seventh Street SW Washington, DC 20590

RE: Motorcycle Headlamp Cover

Dear Mr. Vinson:

On February 1, 1983, members of the motorcycle industry met with you and NHTSA rulemaking (lighting) and enforcement personnel to discuss NHTSA's new interpretation regarding the installation of transparent covers in front of motorcycle headlamps. This interpretation, contained in a December 8, 1982 letter from Frank Berndt, NHTSA Chief Counsel, stated that NHTSA now views that FMVSS 108 prohibits the use of glass or plastic shields in front of motorcycle headlamps. This reverses a previous interpretation contained in a March 15, 1978 letter from Joseph J. Levin, Jr., then NHTSA Chief Counsel, which stated that NHTSA did not read the prohibition against covers as applying to motorcycles equipped with either sealed or unsealed headlamps because the referenced motorcycle headlamp standard in Table III of FMVSS 108, SAE J584, does not prohibit the installation of such covers.

We disagree with the reversal of the earlier interpretation.

Table III of FMVSS 108 requires motorcycles to comply with SAE Standard J584, April 1964. SAE J584 sets forth photometric requirements for motorcycle headlamps and does not prohibit glass covers. It also provides for alternative compliance by fitting headlamps conforming to SAE 579 (which, incidentally, also does not prohibit such covers). S4.1.1.34 provides that a motorcycle may be equipped with various combinations of headlamps from the passenger car headlamp systems, and contains no prohibition of headlamp covers. The only prohibition against the use of headlamp covers in FMVSS 108 is contained in SAE Standard J580a/b, referenced in Table III and applies only to sealed beam headlamps installed in passenger cars, multi-purpose passenger vehicles, trucks and buses. SAE J580a and J580b are concerned with the aim of a headlamp's beam, and proscribe glass covers so the aim can be readily inspected using a mechanical aimer that registers on the headlamp's three aiming pads. J584 motorcycle headlamps do not have these aiming pads, so there is no such need to preclude the use of glass covers.

NHTSA to support its position that Standard 108 precludes the use of covers over motorcycle headlamps relies on two arguments. We disagree with both:

1. That the prohibition contained in SAE Standard J580 applies to motorcycles, since SAE J580 is referenced in Table III of FMVSS 108.

SAE J580 does not apply to motorcycles. It is referenced in Table III of FMVSS 108 only for passenger cars, multipurpose passenger vehicles, trucks and buses. The primary referenced requirement for motorcycles in FMVSS 108 is SAE J584, which contains no such prohibition. SAE J584, in turn, permits alternative compliance with SAE J579, which neither contains such a prohibition nor references J580. In addition, S4.1.1.34 contains additional means of compliance for motorcycles, but no such prohibition.

2. That the "impairs the effectiveness" clause of S4.1.3 of FMVSS 108 precludes the use of such covers because the covers "impair the effectiveness" of headlamps.

This is an improper interpretation of S4.1.3. The impaired effectiveness requirement was intended to preclude the use of devices that render the required devices (although themselves meeting the standard) ineffective. For example, the fitting of a red lamp to a vehicle immediately adjacent to the required amber front side marker lamp and likewise an amber lamp fitted adjacent to the required rear red side marker lamp would impair the effectiveness of the required lamps, as ambiguity would result. Such an impairment would also result from the placement of an extremely bright lamp adjacent to a signal lamp, thus obliterating the light output of the signal lamp. Impairment of effectiveness does not relate to durability requirements as NHTSA would suggest.

In those instances where durability of lamps, lens materials, and other equipment is deemed to be important, FMVSS 108 contains specific durability requirments applicable to such equipment. As long as the headlamp cover does not preclude the headlamp from conforming to the performance requirements specified in FMVSS 108 at the time of sale of the motorcycle, the cover does not "impair the effectiveness" of the required equipment.

The interpretation of December 8 refers to the "impairs the effectiveness" clause of FMVSS 108, S4.1.3, as if impairing were an absolute, regardless of whether an impaired lamp were still within specifications. Compliance with specifications, however, is implicit to S4.1.3 because only lamps complying with specifications are required by this standard. S4.3.1.1. clearly relates compliance of any lamp to meeting or not meeting photometric output.

In addition, the preamble to the January 17, 1983 notice of proposed rulemaking to amend FMVSS 108 (Docket 81-11: Notice 2) discusses the very subject of permissible impairment and concludes that compliance with required photometrics is the only test that can be applied. In rejecting petitioner's argument that conformance of a lamp should be based on relative degradation from the original output, NHTSA states (48 FR 1994), "....a lamp that far exceeded the minimum could "fail" if diminution exceeded 10 percent, even though the safety based J579c minima were still met. Such a result would appear to be excessive as a minimum safety standard. ...NHTSA believes it simpler and preferable that photometric measurements be taken at the end of each of the relevant tests in the sequential test series, and that the lamp at each such point comply with the photometrics of J579c". Thus, this preamble recognizes that photometric standards are composed of minimums and maximums, and that there would be no difference between a lamp designed to lower output and one that deteriorated to that same level, as long as both lamps at the reduced level of output comply with specifications.

That compliance is the sole criterion is further underscored in the letter of interpretation from Frank Berndt, then NHTSA Acting Chief Counsel, to Roderick A. Willcox, July 23, 1976, in which it is stated, in reference to a bug screen placed in front of headlamps, "Since the screen is positioned in front of the headlamps it would be an "other feature" of the type intended to be prohibited by the standard if, as appears likely, it affects compliance with headlamp photometrics (SAE Standard J579 or headlamp aim (SAE Standard J580)."

One of the issues raised at the meeting was whether the BMW headlamp/cover complied with the photometric requirments of FMVSS 108. We indicated to you that we would have such a unit tested at an independent laboratory and submit the results to NHTSA. Electrical Testing Laboratories (ETL) has just completed the environmental and photometric tests prescribed by FMVSS 108 on one of our headlamps, and we attach a copy of their report. The report shows that the headlamp with glass cover passed the photometric tests of SAE J584, April 1964, both before and after the required environmental tests.

BMW uses the J584 motorcycle headlamp because, as recognized by NHTSA in 44 FR 20536, its photometrics are superior for motorcycles. The glass cover is designed as an integral part of the lamp and provides improved aerodynamics, which result in self-cleansing action; the cover also protects the headlamp from impacts and prevents the leadlamp's exposure to rain and dirt. Heat from the headlamp, which is on all the time, is sufficient to prevent buildup of moisture on the cover, while the cover, because of its distance in front of the lamp, minimizes the baking on of dirt and bugs. Generally, we find that most motorcycle owners maintain their vehicles better than do passenger car owners, and tend not to ride them as much in inclement weather.

Also enclosed is a copy of an ETL report showing that the glass cover complies with the light stability, luminous transmittance, impact, fracture and abrasion resistance tests of Z26.1. In the past, both AAMVA and California Highway Patrol have issued certificates of approval on the cover glass, as well as the whole lamp (including the cover glass).

We are not aware of any field experience indicating any problems with discoloration or cracks in the cover glass, or deterioration of the reflector.

Also, as we agreed in our meeting, we are attaching the names and addresses of owners in the Washington, D.C. area of older BMW motorcycles fitted with such covers whom you may wish to contact. This information is being provided to enable you to examine the headlamp/cover assemblies of these older motorcycles to determine what, if any, deterioration in headlamp performance can be attributed to age. This would aid you in the formulation of future proposed rulemaking should you later decide some durability require-ment may be appropriate for such lamp/cover assemblies.

Aside from a perceived (but not demonstrated) durability concern on NHTSA's part with respect to headlamp covers generally, the primary reason repeatedly given by NHTSA in opposition to such covers is their effect on mechanical aimers. Obviously, with a motorcycle there is no such concern since motorcycle headlamps can not be mechanically aimed because mechanical aiming requires the use of two headlamps, while motorcycles are permitted to have only one headlamp. This is the reason a motorcycle headlamp is not required to have the three aiming pads mounted on the lens.

In conclusion, we believe the interpretation contained in the December 8, 1982 Berndt letter is in error, particularly as it would apply to motorcycles equipped with headlamps conforming to SAE J584, as specified by Table III in FMVSS 108. Very truly yours,

Karl-Heinz Ziwica, Manager Safety & Emission Control Engineering

DE/fw 0510 - 83 Attachments

Owners of older BMW motorcycles having cover glass in front of headlamp who are willing to have their headlamps examined:

David Gray 1977 BMW RS 305 Tapawingo Road Vienna, VA 22180 Telephone: 703 938-0060

Robert Henig 1977 BMW RS 11800 Dewey Road 35,000 miles Wheaton, MD 20906 Telephone: 301 942-5198

George R. Sams 1979 BMW RT 1104 Tyler Avenue 21,000 miles Annapolis, MD 21403 Telephone: 301 267-3487 Bus.

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