hearing

5 Hearing Conservation Manual A. Introduction Noise, or unwanted sound, is one of the most pervasive occupational health problems in the workplace. Exposure to high levels of noise can cause hearing loss and may cause other harmful health effects as well. Noise-induced hearing loss can be temporary or permanent. Temporary hearing loss results from short-term exposures to noise, with normal hearing returning after a period of non-exposure. Generally, prolonged exposure to high noise levels over a period of time gradually causes permanent damage. The extent of damage depends primarily on the intensity of the noise and the duration of the exposure. The Occupational Safety and Health Administration’s Occupational Noise Exposure Standard, 29CFR1910.95, requires the establishment of a Hearing Conservation Program when employees are exposed to high noise levels in the workplace. Iowa State University (ISU) Hearing Conservation Program is designed to protect employees from noise exposures that may cause hearing impairment. This program includes the following requirements for employees exposed to a time weighted, eight-hour average (TWA) “action level” of 85 decibels weighted (dBA): • an ongoing program of monitoring, identification, and evaluation of noise hazards • a medical surveillance program which includes annual employee hearing test (audiogram) and appropriate follow-up for individuals who experience work related hearing loss. • employee training on the effects of noise on hearing and the proper use and care of hearing protection • retention of noise monitoring, audiometric testing and training records Participation in the Hearing Conservation Program will be determined based on a noise hazard assessment. Employees participating in the Hearing Conservation Program will be required to wear hearing protection devices, as needed, to reduce noise exposure levels below 90 dBA TWA. Employees who have experienced a standard threshold shift (STS) will have noise exposure levels attenuated below 85 dBA TWA. An STS is a permanent reduction in hearing at several hearing frequencies. Scale of noise sources taken from OSHA’s Occupational Noise Exposure website The Noise Standard requires employers to 1. Measure noise levels 2. Provide free hearing test for exposed employees 3. Inform and train employees 4. Reduce noise exposures through engineering or administrative controls and hearing protection