Degrees of Hearing Loss

The degree of hearing loss is classified by the severity of the loss as shown in this chart:

Degrees of hearing loss Hearing threshold (in decibels, dB) Ability to hear speech
None 0 - 25 dB No perceptible difficulty.
Mild 26 - 40 dB Difficulty hearing soft speech and conversations, especially in noisier or more reverberant situations, but can understand in quiet environments.
Moderate 41 - 55 dB Difficulties understanding speech, especially in the presence of background noise. Higher volume levels are needed for hearing TV or radio.
Moderate to severe 56 - 70 dB Clarity of speech is considerably affected. Speech has to be louder as usual, difficulties in group conversations will occur.
Severe 71 - 90 dB Regular speech is inaudible. Difficulties even with loud speech. Comprehension often only possible through shouting or amplification.
Profound 91+ dB Even amplified speech is difficult to understand or even inaudible.

Degrees of hearing loss in children.

The degree of hearing loss in children depends on the severity of impairment.

Degrees of hearing loss Hearing threshold (in decibels, dB) Ability to hear speech
None 0 - 15 dB Your child experiences no perceptible difficulty.
Minimal hearing loss 16 - 25 dB Comparable to lightly plugging both ears with your fingers. Your child has difficulty hearing very soft speech or speech from a distance. It is harder to hear when there is background noise, like in an auditorium, classroom, or dining room. Hearing aids might be useful, but this depends on the individual.
Mild hearing loss 26 - 40 dB Similar to minimal hearing loss, but with effects that are greater in degree. Your child may hear speech, but certain segments, especially short words, word endings and indistinct word sounds, tend to drop out. Background noise in classrooms and in other listening environments makes it even more difficult for the child to hear. Hearing aids are usually recommended.
Moderate hearing loss 41 - 55 dB Your child may miss over 50% of speech, and even more with the presence of background noise. Hearing aids are necessary to provide amplification. Otherwise, children may have limited vocabulary, produce faint or unclear articulation of speech sounds, and develop limited communication skills. They may also have a flat tone to their voice with only a little inflection or modulation due to their inability to properly monitor their own voice.
Moderate to severe hearing loss 56 - 70 dB Most sounds are not audible to the child. Speech and language skills may not fully develop without proper and early amplification through hearing aids. The child may also need support from speech and language therapists.
Severe to profound hearing loss 71 dB and above Most environmental sounds and even speech are almost inaudible. Speech is unlikely to develop without amplification through hearing aids or other interventions. In addition, children might also be referred to programs that offer specialized instruction in various supportive and alternative communication methods such as lip reading, sign language.
Fluctuating hearing loss Children who frequently have middle ear infections (otitis media) with fluid build-up in the middle ear (effusion) may experience varying degrees of hearing loss. These episodes of temporary hearing loss may last for several months or even longer. Although the hearing loss is mostly temporary and reversible, the child’s speech and language skills may still be affected if the reduced hearing ability persists over a certain period of time. The child may hear, but will constantly miss certain fragments of information.
High-frequency hearing loss 1,500 - 8,000 Hz The child experiences difficulty perceiving consonant sounds. Significant portions of important information may be lost from the speech signal. High levels of background noise will make it even harder to understand speech. This is because background noise contains a lot of low-frequency sounds that are perceived normally by the child, but the high frequencies, which are affected by the hearing loss, carry most of the information necessary for speech intelligibility.
Unilateral hearing loss One ear has normal hearing, while the other has a hearing loss, which can create an imbalance in hearing. The child may have difficulties locating sound sources and voices. In addition, the child may have difficulty separating soft-spoken speech from background noise, especially if the speech is originating from the side with hearing loss. A hearing aid is sometimes recommended. Ongoing audiological monitoring is very important in case a hearing loss should develop in the ear with normal hearing or if the existing hearing loss worsens.