What is the equivalent sound level?

It is calculated according to the formula:

Where:

• T – assessment time;

• LAmi – the average level of sound A occurring during the time when the noise can be considered stable;

• ti –  the time during which the level of sound A is stable and equals LAmi;

• n – the number of time segments ti in the time interval T;

Thanks to this averaging, the level of unstable noise can be compared with the level of stable noise. The equivalent sound level is a single-number parameter that allows assessing the acoustic climate in a given place. For this reason, in standards defining the permissible noise level in a given area, this parameter is used.