Degrees of Hearing Loss
Hearing is measured in decibels along a frequency range.
Decibels (dB) measure the intensity of a sound or volume.
Frequency measures the pitch of a sound in Hertz (Hz)

https://www.aitinstitute.org/audiogram.htm
Normal Hearing (0 – 20dB)
People with normal hearing are able to understand speech in noisy environments without the need for amplification.
Mild hearing loss (21 – 40dB)
- People with mild hearing loss finds difficulty in understanding speech in noisy environments and from a certain distance.
- Soft sounds are hard to hear.
- Children benefit from hearing aids and in class they should be seated near the teacher.
Moderate hearing loss (56 – 70dB)
- People with moderate hearing loss have difficulty in following speech without a hearing aid.
Severe hearing loss (71 -90dB)
- People with severe hearing loss do not understand speech at normal levels.
- They usually rely on lip reading. Use of hearing aids help them to understand speech better.
Profound hearing loss (91dB +)
- People with profound hearing loss hear only very loud sounds.
- Hearing aids help to obtain cues from the environment.
- Facial expressions and lip reading help to communicate.
- Extensive training is required to develop speech.
- These people are definitely cochlear implant candidates.

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