Leq integrates squared pressure over time to yield an equivalent constant sound level

Evidence

This measure integrates the instantaneous squared pressure over some time interval, such as 15 min or 8 h, and then takes the square root of the result. This provides an estimate of the root mean square level of the signal over the time period of the measurement and so gives the equivalent sound level for the time period. That is, the output of the Leq measurement is the constant sound pressure level, which is equivalent to the varying sound level over the measurement period. The Leq measurement also provides a means of estimating the total energy in the signal by squaring its output. A series of Leq measurements over short times can also be easily combined to provide a longer time Leq measurement by simply squaring the individual results, adding them together, and then taking the square root of the result, as shown in Equation 2.7. — David Howard, Jamie Angus, coustics and Psychoacoustics, 629

Categorization

• DEFINE: Explains what the Leq measurement is and does — the root-mean-square energy-equivalent level over a time window.
• corroborated: 2 independent passages support this claim — David Howard, Jamie Angus, coustics and Psychoacoustics, 629
• XREF: connects to: Leq integrates squared pressure over time to estimate noise exposure; Sound level meters need time averaging to estimate varying pressure levels — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 637; Leq reduces varying noise to an equivalent constant sound level — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 639