Leq measurement integrates squared pressure to yield an equivalent constant 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 M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 639
Categorization
Category: Definitional Content
- DEFINE: Explains exactly how Leq works mathematically in accessible terms, distinct from simple time-averaging on a meter.
- XREF: Connects to my earlier readings on noise exposure thresholds and fight-or-flight noise responses in One Square Inch of Silence.
Related
- Leq integrates squared pressure over time to yield an equivalent constant sound level (similarity 0.97)
- Leq reduces varying noise to an equivalent constant sound level (similarity 0.96)
- Leq integrates squared pressure over time to estimate noise exposure (similarity 0.94)
- Sound level meters need time averaging to estimate varying pressure levels (similarity 0.89)
- Measuring noise exposure over time requires Leq, not standard meter settings (similarity 0.83)
- Leq measurements assess cumulative noise exposure linked to hearing loss (similarity 0.83)