Group mean hearing threshold changes in a noise-exposed industrial population using personal hearing protectors.

The audiometric test data of 265 employees in one facility were studied to determine group mean hearing threshold changes. The data covered seven to thirteen years. During this time the population was exposed to workplace noise (OSHA) exposures of 86 to 103 dBA. Personal hearing protection was used. Essentially no change in the mean threshold hearing level was found. Certain other hearing conservation program effectiveness indicators also were used to evaluate this population. The results of these indicators were used to evaluate this population also. The results of these indicators generally follow the trends for effective programs.