Sound intensity or acoustic intensity ($I$) is defined as the sound power $P_a$ per unit area $A$. The usual context is the noise measurement of sound intensity in the air at a listener's location as a sound energy quantity.
Applicable units are those of quantitykind:PowerPerArea
http://en.wikipedia.org/wiki/Sound_intensity
Sound intensity or acoustic intensity ($I$) is defined as the sound power $P_a$ per unit area $A$. The usual context is the noise measurement of sound intensity in the air at a listener's location as a sound energy quantity.
$I = pv$, where $p$ is the sound pressure and $v$ is sound particle velocity.