Noise exposures of rail workers at a North American chemical facility

Background: Both continuous and impact noise exposures of rail yards and railways have been historically understudied. We summarize noise exposures to rail workers at a large chemical facility in North America. Methods: Rail workers were surveyed over the course of three 12-hr shifts. Personal noise dosimeters were used to derive a 12-hr time-weighted average (L_AVG), an 8-hr time-weighted average (L_TWA) and a percent dose. Peak and maximum sound levels were also recorded during each sampling period. Six workers were sampled on three separate days for a total of 18 full-shift noise samples. Results: Full-shift noise exposures were all below the Occupational Safety and Health Administration's (OSHA) permissible exposure limit (PEL) and action level for a 12-hr workday. Peak impact sound levels exceeded 140 dB in 17 of 18 samples (94%) with a mean peak sound level of 143.9 dB. Maximum continuous sound levels were greater than 115 dBA in 4 of 18 samples (22%) with a mean maximum sound level of 113.1 dBA. The source of peak impact sound levels was a daily exposure to a concussion caused by a sudden break in a freight airline. Conclusions: Rail workers at this facility are at risk of noise induced hearing loss from high impact noise exposures. Peak impact and maximum continuous sound levels can be attenuated through the use of hearing protection or by increasing distances from railroad noise sources.