Laserfiche WebLink
Administrative Draft Environmental Impact Report <br /> Gill Medical Center Project <br /> Recommended Standard: Occupational Noise Exposure prepared in 1998 by NIOSH. A division of the US <br /> Department of Health and Human Services, NIOSH identifies a noise level threshold based on the <br /> duration of exposure to the source. The NIOSH construction-related noise level threshold starts at 85 dBA <br /> for more than 8 hours per day;for every 3-dBA increase, the exposure time is cut in half.This reduction <br /> results in noise level thresholds of 88 dBA for more than 4 hours per day, 92 dBA for more than 1 hour per <br /> day, 96 dBA for more than 30 minutes per day, and up to 100 dBA for more than 15 minutes per day. For <br /> the purposes of this analysis, the lowest, more conservative threshold of 85 dBA Leq is used as an <br /> acceptable threshold for construction noise at the nearby existing and future planned sensitive receptors. <br /> The anticipated short-term construction noise levels generated for the necessary equipment for Phase 1 <br /> and Phase 2 of construction are presented in Table 4.15-10. Consistent with FTA recommendations for <br /> calculating construction noise, construction noise was measured from the center of the Project site (FTA <br /> 2018).As shown in Table 4.15-10, no individual or cumulative pieces of construction equipment would <br /> exceed the 85 dBA NIOSH construction noise standard during any phase of construction at the nearby <br /> noise-sensitive receptors.The Project would result in a less than significant impact from construction <br /> noise. <br /> Table 4.15-10.Unmitigated Construction Average(dBA)Noise Levels at Nearest Receptor <br /> Estimated Exterior <br /> Construction Construction <br /> Equipment Noise Level at Noise Exceeds <br /> Nearest Existing Standards Standards? <br /> Residences (dBA Leq) <br /> each <br /> Phase 1 <br /> Grading&Under roundin <br /> Excavators(2) 60.3 85 No <br /> Rubber Tired Dozers(6) 61.3 85 No <br /> Graders(2) 64.6 85 No <br /> Tractors/Loaders/Backhoes(8) 63.6 85 No <br /> Combined Grading&Undergrounding Equipment 75.4 85 No <br /> Building Construction <br /> Cranes(2) 56.2 85 No <br /> Forklifts(6) 63.0 85 No <br /> Generator Sets(6) 63.0 85 No <br /> Tractors/Loaders/Backhoes(6) 63.6 85 No <br /> Welders(2) 53.6 85 No <br /> Combined Building Construction Equipment 74.3 85 No <br /> Noise 4.15-20 October 2021 <br />