Equivalent Sound Level - Leq - quantifies the noise environment to a single value of sound level for any desired duration
The Environmental Protection Agency - EPA - has adopted a system of four "sound descriptors"
- A-weighted sound level
- Sound Exposure Level - Ls
- Equivalent Sound Level - Leq
- Day-Night Sound Level - Ldn
to summarize how sound is heard and measured, and to determine the impact of noise on health and welfare.
Equivalent Sound Level - Leq
Equivalent Sound Level - Leq - quantifies the noise environment to a single value of sound level for any desired duration. This descriptor correlates well with the effects of noise on people. Leq is also sometimes known as Average Sound Level - LAT.
Equivalent Sound Level - Leq - can be calculated by integrating the sound pressure level over a time period as:
Leq = 10 log [(1/T) ∫ (pA / pref)2 dt ] (1)
Leq = equivalent sound level (dB)
T = time period (s)
pA = sound pressure (Pa, N/m2)
pref = reference sound pressure ( 2 10-5 Pa, N/m2)
- en: equivalent sound level
- es: nivel de sonido equivalente
- de: gleichwertigen Schallpegel