A pneumatic hammer generates a sound level of 100 dB even at a distance of 10 meters. This is so unpleasant, that we try to cover our ears when we pass by a construction site. Loud clubs or concerts reach a continuous sound level of 100 to 120 dB. The enjoyment of the music and the pleasure of participation repress the danger of this sound level.

Continuous exposure to noise levels above 85 dB leads to a disturbance in hearing even after a few hours. At the beginning soft notes are not sensed anymore. This in most cases is temporary. When the ear is subjected to such strain every week for several hours, it can lead to premature and permanent hearing impairment.