Hearing loss prevention

Noise induced hearing loss

Aging, some drugs, head injuries and too much noise can all cause lasting damage to hearing. This handout discusses the most common type of permanent hearing loss -- the loss that results from too much noise.

Frequent exposure to loud or moderately loud noise over a long period of time can damage the soft tissue of the inner ear. Cells and nerves in the inner ear are destroyed by continuous or repeated exposure to loud sounds. If enough cells and nerves are destroyed, hearing is permanently damaged.

Whether noise harms your hearing depends on the loudness, the pitch and the length of time you are exposed to the noise. The loudness of a sound (measured in decibels, or dB) and the length of exposure are related. The louder the sound, the shorter the exposure can be before damage occurs. For example, 8 hours of exposure to 85-dB noise on a daily basis can begin to damage a person's ears over time. Using power tools (at about 100 dB), listening to loud stereo headsets (at about 110 dB), attending a rock concert (at about l20 dB) or hearing a gunshot (at 140 to 170 dB) may damage the hearing of some people after only a few times.