An Etymological Dictionary of Astronomy and Astrophysics

The expression of sound intensity in decibel units. The sound intensity level
(L_I), in decibels, is computed as: L_I = 10 log (I/I₀), where I is the measured sound intensity and I₀ is the reference intensity (1 x 10 ^-12 watt per square meter).

See also: → sound; → intensity; → level.