1. It is always sensorineural.
2. It is nearly always bilateral and symmetric.
3. It will only rarely produce a profound loss.
4. It will not progress once noise exposure is stopped.
5. The rate of hearing loss decreases as the threshold increases.
6. The 4kHz frequency is the most severely effected and the higher frequencies (3-6kHz) are more affected than the lower frequencies (500Hz-2kHz).
7. Maximum losses typically occur after 10-15 years of chronic exposure.
8. Continuous noise is more damaging than intermittent noise (5,6).