WAC 296-307-63405. Make sure that noise-measuring equipment meets recognized standards

(1) The employer must make sure that noise dosimetry equipment meets these specifications: Dosimeters must be equipment class 2AS-90/80-5 of the American National Rule Specification for Personal Noise Dosimeters, ANSI S1.25-1991, such dosimeters are normally marked "Type 2." Note: Make sure any dosimeter used is Type 2 equipment that: 1. Uses slow integration and A-weighting of sound levels. 2. Has the criterion level set to 90 dB, so the dosimeter will report a constant 8-hour exposure at 90 dBA as a 100% dose. 3. Has the threshold level set at 80 dB, so the dosimeter will register all noise above 80 dB. 4. Uses a 5 dB exchange rate for averaging of noise levels over the sample period. (2) The employer must make sure that sound level meters meet these specifications: (a) American National Standard Specification for Sound Level Meters, S1.4-1984, Type 2 requirements for sound level meters, such sound level meters are normally marked "Type 2." (b) For continuous noise measurements, the meter must be capable of measuring A-weighted sound levels with slow response. (c) For impulse or impact noise measurements, the meter must be capable of indicating maximum C-weighted sound level measurements with fast response. (3) The employer must calibrate dosimeters and sound level meters used to monitor employee noise exposure: (a) Before and after each day's use; and (b) Following the instrument manufacturer's calibration instructions. Notes: 1. The employer may conduct dosimetry using an exchange rate less than 5 dB and compare the results directly to the noise evaluation criteria in Table 1. 2. For measuring impulse and impact noise the employer may also use a sound level meter set to measure maximum impulse C-weighted sound levels or peak C-weighted sound levels.