Konieczność użycia w podanym kontekście terminu "deaf" wynika z poniższych opisów. Natomiast słowo "głuchy" oddałbym jednym z określeń występujących poniżej.

The difference between deaf and hearing-disabled
There have been long debates as to the correct terms to use to describe someone with a hearing loss. Terms such as deaf, hard of hearing, hearing impaired and hearing disabled are some of the terms sparking those debates. All these terms refer to someone with a hearing loss, the difference being mainly the connotation attached to the word.

There are different degrees of hearing loss, ranging from mild to profound. The person with a profound hearing loss is considered deaf. The person with a lesser degree of hearing loss is considered hard of hearing or hearing disabled. These two terms fall under the broad category of hearing impaired. Hearing impaired is used more often by hearing people as they try to soften the impact of the word deaf. However, despite the term used, any degree of hearing loss indicates a hearing impairment.
Hearing is measured in decibels (dB). Decibel is a unit used for measuring the loudness of sound. Normal hearing is represented by 0 dB and a loss of up to 25 dB is considered in the normal range. Hard of hearing is in the range 26 - 75 dB, going from mild to severe. Deaf falls in the range 76 - 105 dB, with 105 dB considered profoundly deaf.

By definition, a hearing-disabled person is one whose hearing is defective to the extent that it makes it difficult but not impossible to understand speech with or without a hearing aid. In the case of children, those who are hard of hearing learn to speak through the avenue of hearing, although there may be defects. They are most likely able to attend classes with normal hearing peers. Hard of hearing adults are able to function normally in society with or without the use of hearing aid. Some of them rely on lip reading in addition to the hearing aid.

On the other hand, the deaf are those whose hearing is disabled to the extent that it precludes the understanding of speech and the acquisition of language. To further explain, the deaf are those for whom the sense of hearing is so limited as to be considered non-functioning for the ordinary purposes of life. Deaf children require specialized instruction to learn, to talk or to acquire a substitute mode of communication. Many deaf people use sign language as their primary mode of communication.
http://tinyurl.com/3y4l5h3

Hearing impairment or hard of hearing or deafness refers to conditions in which individuals are fully or partially unable to detect or perceive at least some frequencies of sound which can typically be heard by members of their species. Use of the term impaired implies that deafness presents an inherent disadvantage to an animal, a view that is rejected within the Deaf culture movement, where the terms Deaf and hard of hearing are preferred.
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Those who are hearing disabled do have access to a free and appropriate public education. If a child does qualify as being hearing impaired and receives an individualized education plan, the IEP team must consider...
http://en.wikipedia.org/wiki/Hearing_impairment