Profound hearing loss
Profound hearing loss is defined as a hearing threshold greater than 90 decibels (dB) — meaning that an individual with profound hearing loss can only hear sounds that are louder than 90 dB. A person with normal hearing can detect sounds between 0 dB and 20 dB.
For comparison with other levels of hearing loss, see Quantification of hearing loss.
- "Profound Hearing Loss" from The Queensland Department of Education and the Arts