A normal range may show a loss of 25 decibels. OSHA requires audiometric baseline and yearly evaluations. If hearing changes of 10 decibels at 2.3 and 4 kHz occurs in either ear, and action is required. Effective methods to save your hearing could include covering the walls of the rehearsal room with carpet. This will prevent the echo chamber effect and reduce the loudness of sound.
Musicians earplugs are also effective.
They reduce the sound level by 30 decibels. Partitioning off the percussion section with clear plexiglass is another technique currently being used. Most importantly, music teachers should get a baseline hearing test done in a doctor s office or by an audiologist. Hearing tests should be taken at regular intervals. The results of the test can be compared to determine whether damage to the hearing has occurred.