R. Kring Herbert
Ostergaard Acoust. Assoc., 100 Executive Dr., W. Orange, NJ 07052
Classrooms for the teaching and rehabilitation of hearing-impaired children pose special problems in acoustical design. Both Elliot [L. L. Elliot, J. Acoust. Soc. Am. 66, 12--21; 651--653 (1979)] and Mills [J. Acoust. Soc. Am. 58, 767--779 (1975)] have shown that the levels of noise which interfere with speech perception in children without hearing impairment are lower than those which interfere with intelligibility in adults. It is logical to conclude, therefore, that the design of rooms in schools for the hearing impaired should include criteria more stringent than those for other classrooms. This approach was adopted in establishing criteria for the Summit Speech School which conducts two distinct programs of speech training for hearing impaired children: One for children from birth to age three and the other, for ages 21/2 to 5. Several factors were identified for particular attention including control of activity noise without excessive sound absorption and control of flutter echo. Among the criteria recommended were minimum sound isolation between classrooms and other spaces of STC-48 and maximum background sound levels of RC-25. Criteria for other spaces and their basis will be presented.