Ralph G. Leverett, Ph.D., University Professor of Special Education, Hendersonville
November 1, 2003 - The following is a summary of the presentation by Carrie Crittendon, Jeannie Seneker, Kris Wolfe, and Ralph Leverett:
The average classroom is noisy. This creates an environment incompatible with maximum performance for students with hearing loss, certain language disorders (Central Auditory Processing Disorder in particular), students with Attention Deficit Disorders, and some students with Learning Disabilities.
The noise level of the “average unoccupied classroom” is approximately 41-50dB (decibels). This is at the low end of the range of average speech loudness. The American-Speech-Language-Hearing Association recommends ambient noise levels (background noise) no louder than 30-35dB. This level is almost impossible to achieve in the average classroom even with the addition of carpeting, curtains or drapes and acoustic tile.
Teachers, on the average, have difficulty speaking “over” the noise level of their classrooms. Generally, teachers may speak at 4dB above the level of background noise. Again, the American Speech-Language-Hearing Association recommends that teachers speak 15dB above the level of background noise. This is almost impossible to achieve for a brief period, and is certainly an unlikely accomplishment for even a single class period. Our ability to hear efficiently has little to do with how loud something is said. It is much more related to how loud speech is compared to everything else in the environment of the classroom.
What can improve the classroom climate? Sound systems, particularly FM sound systems, can improve the signal-to-noise ratio (teacher’s voice to background noise) appreciably and with much less effort that the teacher’s struggle to speak above background noise through human effort alone. These systems are affordable. The average cost of a portable FM system with a speaker that can be moved for maximum benefit to students is less than $1,000. These systems benefit the entire classroom, and, in the instance of trying to meet the needs of several students in a classroom, the cost is essentially the same as the equipment required to help a single student (a personal amplification system).
These systems do not compensate for moderate, severe, or profound hearing losses. They do, however, allow schools to provide help for students with mild hearing losses and other students described earlier in this summary.
For additional information on the availability and use of these systems, contact any of the following:
Carrie Crittendon, M. A., CCC-A
Jeannie Seneker, M. S., CCC-A
Kris Wolfe, M. S., CCC-SLP
Ralph Leverett, Ph.D., CCC-SLP
at 731-661-5385 or
Presented at the October 2003, West Tennessee Special Education Conference Memphis, TN