Federal regulations published in 1977 define "handicapped children" to include those who are Deaf or Hard of Hearing and who, because of those impairments, need special education and related services.

"Deaf" means a hearing impairment that is so severe that the child is impaired in processing linguistic information through hearing, with or without amplification, which adversely affects educational performance.

"Hard of Hearing" means a hearing impairment permanent or fluctuating, which adversely affects a child's educational performance but which is not included under the definition of "deaf" in this section.