Wash. Admin. Code § 296-307-63415
Current through Register Vol. 24-23, December 1, 2024
The employer must compute employee's full-day noise exposure by using the appropriate equations from Table 3 "Noise Dose Computation" when using a sound level meter to estimate noise dose.
Table 3 Noise Dose Computation
| Description | Equation |
| 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 |
Wash. Admin. Code § 296-307-63415
Statutory Authority: RCW 49.17.010, 49.17.040, 49.17.050, 49.17.060. 05-01-166, § 296-307-63415, filed 12/21/04, effective 4/2/05.