Definition of noise

INTENSITY OF NOISE

The intensity corresponds to the sound volume and is measured physically in decibels (dB) using a sound level meter. In order to take account of the level actually perceived by the ear, a physiological decibel is used: the decibel A: dB(A). The audibility threshold is set at 0 dB and that of pain at 120 dB.

• The intensity of the noise decreases with distance. The sound level measured at 100 dB(A) at 1 m decreases to 94 dB(A) at 2 m and to 88 dB(A) at 4 m.
• Lorsqu'on multiplie les sources sonores, l'intensité ne suit pas une progression mathématique égale au nombre de sources.
• If the intensity of one sound is very much greater than the intensity of another, the latter may not be heard. A portion of the acoustic information is lost or poorly interpreted, hence the risk of accidents.

Discover the sound scale

Quizz :

1 pneumatic drill = 90 dB(A),
what is the sound level of 2 pneumatic drills?

View the answer