Page "Deafness" Paragraph 12

Many people are unaware of the presence of environmental sound at damaging levels, or of the level at which sound becomes harmful.

Common sources of damaging noise levels include car stereos, children's toys, transportation, crowds, lawn and maintenance equipment, power tools, gun use, and even hair dryers.

Noise damage is cumulative ; all sources of damage must be considered to assess risk.

If one is exposed to loud sound ( including music ) at high levels or for extended durations ( 85 dB A or greater ), then hearing impairment will occur.

Sound levels increase with proximity ; as the source is brought closer to the ear, the sound level increases.