Environmental Noise Level Check
Most local agencies and schools do not have the equipment to take ambient noise level measurements in the areas to be used for screening. A BIOLOGIC NOISE LEVEL CHECK MAY BE SUBSTITUTED. THIS IS DEFINED AS THE ABILITY TO ESTABLISH THRESHOLDS AT 10dB BELOW THE SCREENING LEVEL AT ALL FREQUENCIES ON A PERSON WITH KNOWN NORMAL HEARING. If these thresholds cannot be established, the area must not be used for screening. However, if 500 Hz is the only frequency affected, then it may be deleted from the screening protocol.