Interpretation ID: aiam3144
Vice President - Technical Affairs
SEV Corporation 33201 Harper Avenue
St. Clair Shores
MI 48082;
Dear Mr. Young: This is in reply to your letter of September 24, 1979, to Mr. Vinson o this office in which you requested an interpretation S4.1.1.19 of Federal Motor Vehicle Safety Standard No. 108.; S4.1.1.19 states: >>>A lamp manufactured on or after January 1, 1974 and designed to us a type of bulb that has not been assigned a mean spherical candlepower rating by its manufacturer and is not listed in SAE Standard J573d 'Lamp Bulbs and Sealed Units', December 1968, shall meet the applicable requirements of this standard when used with any bulb of the type specified by the lamp manufacturer, operated at the bulb's design voltage. A lamp that contains a sealed-in bulb shall meet these requirements with the bulb operated at the bulb's design voltage.<<<; It is noted that this paragraph consists of two sentences. You hav asked whether the 'lamp' and 'bulb' of the second sentence are the same 'lamp and bulb' of the first sentence.; The answer is no. The first sentence would require testing, at th bulb's design voltage, of bulbs used in sealed beam headlamps but not of bulbs used in, for example, taillamps. The former, though listed in J573d (Table 2), is not assigned a mean spherical candlepower rating since these bulbs emit shaped beams while the latter is used in the sealed lamp, it is tested at the bulb's design voltage rather than using the rated mean spherical candlepower. Furthermore, the rulemaking history of the paragraph clearly indicates that the two requirements are separate. As the agency noted in the preamble to the proposal, 'The proposal specifies that when no rating has been assigned by the bulb manufacturer or the SAE *or* if the lamp is sealed and the bulb cannot be replaced, the bulb shall be operated at design voltage' (emphasis supplied) (38 FR 16230).; You noted that your question relates to the voltage required b Standard No. 108 for the photometric testing of a sealed beam headlamp that utilizes a European halogen bulb that meets ECE Regulation 37.; Since J579c requires the test voltage to be 12.8 volts for all th sealed beam bulbs, the photometric test should be at 12.8 volts and not at the so-called 'system voltage' of 12 volts.; I hope this is responsive to your request.