Sound Level

Sound level refers to various logarithmic measurements of audible vibrations and may refer to as, sound exposure level, measure of the sound exposure of a sound relative to a reference value.  Sound power level, measure of the rate at which sound energy is emitted, reflected, transmitted or received, per unit time.

It can be helpful to use normal sounds you encounter every day as a rough scale for decibel levels:
  • 10 dB: Normal breathing
  • 20 dB: Whispering from five feet away
  • 30 dB: Whispering nearby
  • 40 dB: Quiet library sounds
  • 50 dB: Refrigerator
  • 60 dB: Electric toothbrush
  • 70 dB: Washing machine
  • 80 dB: Alarm clock
Noise level PPT from CDC