Interpretation ID: nht93-7.8

DATE: October 4, 1993

FROM: James E. Walker -- Manager, LSI Laboratories, Lighting Sciences Inc.

TO: John Womack -- Acting Chief Counsel, NHTSA

TITLE: None

ATTACHMT: Attached to letter dated 11/16/93 from John Womack to James E. Walker (A41; Std. 108)

TEXT:

I am writing to you at the suggestion of Richard Van Iderstein, NHTSA; recently, LSI Laboratories conducted a test on a customer's product - a tail light. At the conclusion of the test LSI Laboratories was unable to determine pass/fail criteria. Our discussion with Mr. Van Iderstein lead us to believe CFR 49, Ch. V Part 571, Federal Motor Vehicle Safety Standard No. 108 has a discrepancy. The discrepancy exists in paragraph S5.1.1.11 referencing the tail lamp. S5.1.1.11 states:

A ..., tail lamp, ..., shall meet the minimum percentage specified in Figure 1a of the corresponding minimum allowable value specified in Figure 1b. The values specified in Figure 1a and Table 1 and Table 3 of SAE J588 NOV84 Turn Signal Lamps are substituted for those specified in Table 1 of the Following SAE Standards: ..., J585e Tail Lamps (maximum at H or above), ... .

The discrepancy is that para. S5.1.1 requires equipment to be designed to Tables I, II and S7, which references SAE J585e for the Tail Lamp. Para. S5.1.1.11 requires Table 1 of this specification to be substituted for the values achieved by Figures 1a and 1b, and in addition, to substitute Table 1 of SAE 585e by the values achieved by multiplying the percentages of Figure 1a by Tables 1 and 3 of SAE J588 NOV84 Turn Signal Lamps.

LSI Laboratories would assume that the photometric requirements are those of Figure 1a, 1b, and 1c of 49 CFR Ch. V Part 571 Federal Motor Vehicle Safety Standard No. 108.

It is hoped your clarification would allow LSI Laboratories to compare performance to establish pass/fail criteria. This would allow our customer to begin production or re-design.