Hearing: the effects of noise.
Otolaryngol Head Neck Surg 1992 Jun; 106(6):669-676
The effects of noise exposure on hearing were discussed. Mechanisms of noise induced hearing loss were reviewed. The ear may be injured by noise in two different ways: acoustic trauma and metabolic trauma. Noises in the environment that can cause acoustic trauma usually involve explosive events such as firecrackers detonating near the head. Metabolic hearing damage is caused by noises having intensities of 90 to 140 decibels-A (dBA). The extent of damage depends on the level and duration of exposure. This type of damage is referred to as noise induced hearing loss. Noise induced hearing loss has been traditionally associated with occupational noise and occurs slowly over a period of years. It can be caused by any noise exposure that regularly exceeds a time weighted average (TWA) exposure of 90dBA. Hearing loss caused by occupational noise exposure was discussed. Regulatory efforts to reduce occupational noise exposure were described. The OSHA standards for preventing TWA occupational exposures of 90dBA of all workers and holding TWA exposures of noise sensitive workers to between 85 and 90dBA are capable of protecting 90% of the exposed workforce. Nonoccupational exposure sources that can cause hearing loss were discussed. Hunting, target shooting and listening to amplified music through headphones or at rock concerts were considered to be the major sources of nonoccupational noise that can damage hearing. Hearing loss risks associated with these sources were discussed.
NIOSH-Publication; NIOSH-Grant; Noise-induced-hearing-loss; Acoustic-trauma; Noise-exposure; Occupational-exposure; Environmental-exposure; Legislation; Hearing-protection; Acute-exposure; Chronic-exposure
Research Central Inst for the Deaf 818 South Euclid St Louis, MO 63110
Otolaryngology - Head and Neck Surgery
Central Institute for the Deaf, Saint Louis, Missouri