An assessment of occupational noise exposures in four construction trades

Three hundred thirty-eight noise exposure samples were collected from 133 c onstruction workers employed in 4 construction trades: carpenters, laborers , ironworkers, and operating engineers. Four sites using a variety of const ruction techniques were sampled at least 12 times on a randomly chosen date over a 22-week period. Up to 10 volunteer workers were sampled for an enti re work shift on each sampling day using datalogging noise dosimeters, whic h recorded both daily time-weighted averages (TWAs) and 1-min averages. Wor kers also completed a questionnaire throughout the workday detailing the ta sks performed and tools used throughout the day. Regression models identifi ed work characteristics associated with elevated exposure levels. Compariso ns were made between exposures measured using the Occupational Safety and H ealth Administration (OSHA) exposure metric and the 1996 draft National ins titute for Occupational Safety and Health/international Organization for St andardization (NIOSH/ISO) metric to examine the effects of differing exchan ge rates and instrument response times on construction noise exposures. The mean OSHA TWA for 338 samples was 82.8 dBA+/-6.8 dBA, whereas the mean NIO SH/ISO TWA for 174 samples was 89.7 dBA+/-6.0 dBA. Forty percent of OSHA TW As exceeded 85 dBA, and 13% exceeded 90 dBA, the OSHA permissible exposure limit. The tasks and tools associated with the highest exposure levels were those involving pneumatically operated tools and heavy equipment. Trade wa s a poor predictor of noise exposure; construction method, stage of constru ction, and work tasks and tools used were found to be better exposure predi ctors, An internal validation substudy indicated excellent agreement betwee n worker self-reporting and researcher observation. These data provide subs tantial documentation that construction workers in several key trades are f requently exposed to noise levels that have been associated with hearing lo ss, and demonstrate the need for targeted noise reduction efforts and compr ehensive hearing conservation programs in the industry.