How to Test Hearing Protector Devices
- 1). Position the listener's chair in the sound-treated room at the calibrated position facing the speaker.
- 2). Tell the listener that he will be tested without the hearing protection devices.
- 3). Instruct the listener to raise his hand each time he hears a sound called a warble tone.
- 4). Set the frequency control to 1000 Hz and set the intensity level to 60 dB.
- 5). Present the warble tone for one second and wait for the listener to respond.
- 6). Lower the intensity level by 10 dB if the listener raises his hand, then present the softer warble tone.
- 7). Repeat Step 3 until the listener no longer raises his hand, indicating that he did not hear it.
- 8). Raise the intensity level 5 dB, then present the warble tone and wait for the listener to respond.
- 9). Raise the intensity level another 5 dB if the listener does not respond. Continue to raise the level in 5 dB steps until the patient responds.
- 10
Note the intensity level on the audiogram when the patient responds. - 11
Repeat Steps 6 through Steps 10 until the same intensity level is noted two or three times. This is the threshold or softest level that the listener can hear that frequency. - 12
Repeat Steps 2 through 8 for test frequencies 2000 Hz, 4000 Hz, 8000 Hz, 250 Hz, and 500 Hz. Proceed to Step 13 when testing of 500 Hz is completed. - 13
Instruct the listener to put on his hearing protection device then repeat Steps 4 through 12. Go to step 14 when Step 13 is completed. - 14
Calculate the amount of sound protection at each frequency by subtracting the thresholds measured without hearing protection from the thresholds measured with the devices.
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