Characteristic Symbols Particle velocity v, SVL Sound intensity I, SIL | Sound pressure p, SPL Particle displacement δ Sound power P, SWL | |
Sound exposure is the integral, over time, of squared sound pressure. The SI unit of sound exposure is the pascal squared second (Pa2·s).
Contents
Mathematical definition
Sound exposure, denoted E, is defined by
where
Sound exposure level
Sound exposure level (SEL) or acoustic exposure level is a logarithmic measure of the sound exposure of a sound relative to a reference value.
Sound exposure level, denoted LE and measured in dB, is defined by
where
The commonly used reference sound exposure in air is
The proper notations for sound exposure level using this reference are LW/(400 μPa2⋅s) or LW (re 400 μPa2⋅s), but the notations dB SEL, dB(SEL), dBSEL, or dBSEL are very common, even if they are not accepted by the SI.
References
Sound exposure Wikipedia(Text) CC BY-SA