Setting Guidelines for Classroom Acoustics
Jul 1, 2000 12:00 PM, By Mike Kennedy
Accessibility is not just a matter of getting in and around a school facility. A classroom with poor acoustics can make the educational program inaccessible for students who have trouble hearing their teachers, fellow students or audio materials.
The Access Board, the federal agency responsible for developing accessibility guidelines under the Americans with Disabilities Act (ADA), is working with industry groups to devise acoustical standards for school classrooms. ADA guidelines do not include "provisions for the acoustical design or performance of spaces within buildings and facilities," the board notes. Acting on the request of the parent of a child with hearing loss, the Access Board began gathering public opinion on the issue two years ago.
"Studies of elementary and secondary school classrooms revealed that excessive background noise, which competes with the speech of teachers, aides, classmates and audio educational media, is common even in new classrooms," the board says.
The board decided to work with a committee already formed by the Acoustical Society of America and the American National Standards Institute's Committee on Noise, which already were working to develop classroom acoustical standards.
With the involvement of the Access Board, the committee broadened its membership to include more educators, school designers and representatives of disability organizations.
Familiar standards Lois Thibault, with the Access Board's office of technical and information services, says the proposed guidelines probably will recommend maximum background noise levels of about 35 decibels and reverberation times of about 0.5 seconds.
"We won't be proposing anything that those familiar with acoustical designing don't already take into account," says Thibault.
Reducing background noise and reverberation in classrooms would be most beneficial to students with hearing loss, learning disabilities, or those who are very young or for whom English is a second language, says Thibault.
The board expects that a draft of the proposed standards could be presented sometime in 2001.
In the meantime, it has offered technical assistance for those seeking to provide an acoustical environment conducive to listening and learning.
The Access Board encourages collaboration between schools, designers and manufacturers to reduce the noise levels in classrooms. More generally, the board encourages schools to consider acoustical designs with:
-Site, space and classroom adjacencies that minimize classroom exposure to environmental, equipment and occupancy noise.
-Room sizes and proportions for appropriate sound reflection and absorption.
-Slabs, ceilings, roofs and walls (as well as doors and windows) that are appropriate barriers to noise.
-HVAC equipment selection, design and installation that minimize structure, duct and operating noise.
-Finishes that are selected and placed for proper control of reverberation.
-Attention to electronic and radio-frequency interference with assistive devices.
