Occupational exposures to noise resulting from the workplace use of personal media players at a manufacturing facility

Abstract

This study examined the contribution of noise exposures from personal media player (PMP) use in the workplace to overall employee noise exposures at a Colorado manufacturing facility. A total of 24 workers' PMP and background noise exposures were measured. Twelve PMP users worked in high-background-noise exposure (HBNE) areas, and 12 worked in low-background-noise exposure (LBNE) areas. The self-selected PMP listening level of each worker was measured using an ear simulator, and the background noise of each employee workstation was measured using a sound level meter. Workers' self-reported PMP duration of use, PMP listening exposure levels, and background noise levels were used to estimate the daily occupational noise exposures. Measured background noise levels averaged 81 dBA for HBNE workers and 59 dBA for LBNE workers. Measured, free-field equivalent listening exposure levels were significantly greater for HBNE workers (85 dBA) compared with LBNE workers (75 dBA) (p = 0.0006). Estimated mean daily noise exposures for both groups were below the ACGIH threshold limit value for noise of 85 dBA8-hr time weighted average (TWA), specifically 84 dBA TWA for HBNE workers and 72 dBA TWA for LBNE workers. Three of 12 (25%) HBNE workers had estimated exposures greater than 85 dBA TWA when only background noise was considered, yet when PMP use was also considered, 6 of 12 (50%) had estimated exposures greater than 85 dBA TWA, suggesting that PMP use doubled the number of overexposed workers. None of the LBNE workers had estimated exposures greater than 85 dBA TWA. The contribution of PMP use to overall noise exposures was substantially less among HBNE workers than LBNE workers due to the disproportionate selection of noise-attenuating headsets among HBNE workers compared with LBNE workers. It is recommended that the facility management either restrict workplace PMP use among HBNE workers or require output-limiting technology to prevent occupational noise-induced hearing loss.