Compute the noise dose based on several time periods of constant noise during the shift

The total noise dose over the work day, as a percentage, is given by the following equation where Cn indicates the total time of exposure at a specific noise level, and Tn indicates the reference duration for that level.

D = 100*((C1/T1) + (C2/T2) + (C3/T3) + ... + (Cn/Tn))

The reference duration is equal to the time of exposure to continuous noise at a specific sound level that will result in a one hundred percent dose

The reference duration, T, for sound level, L, is given in hours by the equation:

T = 8/(2^((L - 90)/5))

Given a noise dose as a percentage, compute the equivalent eight-hour time weighted average noise level

The equivalent eight-hour time weighted average, TWA8, is computed from the dose, D, by the equation:

TWA8 = 16.61* Log10(D/100) + 90