important:
A noise dosimeter is the basis for determining total daily noise exposure for employees. However, where there is constant noise levels, the employer may estimate employee noise exposure using measurements from a sound level meter. Calculation of the employee noise exposure must be consistent with WAC
296-307-63415.
(1) The employer must include all:
(a) Workplace noise from equipment and machinery in use;
(b) Other noise from sources necessary to perform the work;
(c) Noise outside the control of the exposed employees.
(2) The employer must use a noise dosimeter when necessary to measure employee noise dose.
(3) The employer must use a sound level meter to evaluate continuous and impulse noise levels.
(4) The employer must identify all employees whose exposures equal or exceed the Noise Evaluation Criteria as follows:
Noise Evaluation Criteria
Criteria | Description | Requirements |
85 dBA TWA8 | Full-day employee noise exposure dose. If you have one or more employees whose exposure equals or exceeds this level, you must have a hearing loss prevention program | – Hearing protection – Training – Audiometric testing |
90 dBA TWA8 | Full-day employee noise exposure dose. If you have one or more employees whose exposure equals or exceeds this level, you must reduce employee noise exposures in the workplace | Noise controls (in addition to the requirements for 85 dBA TWA8) |
115 dBA measured using slow response | Extreme noise level (greater than one second in duration) | – Hearing protection – Signs posted in work areas warning of exposure |
140 dBC measured using fast response | Extreme impulse or impact noise (less than one second in duration) | Hearing protection |
[Statutory Authority: RCW
49.17.010,
49.17.040,
49.17.050, and
49.17.060. WSR 20-21-091, § 296-307-63410, filed 10/20/20, effective 11/20/20; WSR 05-01-166, § 296-307-63410, filed 12/21/04, effective 4/2/05.]