A sawmill environment: noise levels, controls, and audiometric test results.
Appl Occup Environ Hyg 1991 Dec; 6(12):1000
NIOSH investigators were asked to investigate the effects of moving some of the equipment at a sawmill on noise levels to which the workers were exposed. Noise measurements indicated the workers were consistently exposed to noise levels in excess of the OSHA PEL of 90 decibels on the slow A-weighted scale. Engineering controls attempted by the sawmill fell into two categories. The first was enclosing the noise sources. The second type of control was the separation of operations into their own distinct buildings. The separation of the trimmer operation from the main sawmill was complete before the initial survey was completed, thereby eliminating the possibility of determining the effect of this move. Hearing tests revealed that 72.5% of the employees exhibited some degree of hearing impairment at one or more audiometric test frequencies. The mean hearing curves demonstrated a pattern associated with noise induced hearing losses, characterized by maximum hearing loss at 4 to 6 kilohertz with better hearing at adjacent higher and lower frequencies.
NIOSH-Author; Noise-exposure; Noise-induced-hearing-loss; Sawmill-workers; Lumber-industry; Industrial-noise; Workplace-studies; Ear-disorders; Hearing-threshold; Sensory-thresholds
Applied Occupational and Environmental Hygiene