Auditory System: Damage Due to Overstimulation

Sound is the stimulus that activates the hair cells in the inner ear and starts the sequence of chemical and electrical processes that activate auditory nerve fibers and ultimately lead to perception. Sound that is too loud and lasts too long can severely damage the hair cells, can reduce or abolish activation of auditory nerve fibers, and can lead to impaired perception. This entry discusses damage to the auditory system caused by over-stimulation.

Noise exposure levels are strictly regulated in the workplace to prevent hearing loss; typically a level of exposure of about 80 to 85 dB(A) is allowed for 8 hours, depending on the jurisdiction, and assumes the remaining 16 hours per day to be noise free. Every 3 dB(A) increase in sound level would ...