Researchers creating devices to improve critical communications

Airplane pilots, military personnel, and others who work in noisy environments may benefit from research conducted at the Health Center’s new acoustics laboratory.

The project involves studying the effectiveness of hearing protectors equipped with noise reduction systems either mounted in a headset or worn in the ear canal.

“We are working on hearing protector technology that can combine noise reduction systems to prevent hearing loss, while at the same time enhancing speech and the ability to hear warning alarms,” says Anthony Brammer of the Biodynamics Laboratory, chief investigator on the study.

“The devices are designed to maintain speech intelligibility and will be especially useful in circumstances where clear communications are critical,” he says.

People working in environments with high noise levels have long complained that hearing protection devices interfere with their ability to communicate and to hear warning alarms, says Brammer. He recently gave a presentation on the effects of noise on speech and communications to a NATO task force investigating noise reduction systems for military applications.

Completed last year, the acoustics laboratory was funded by NASA to conduct voice communications research. The $2 million facility consists of an anechoic chamber (one free from echoes and reverberations), and its counterpart, a reverberation room that minimizes sound absorption. In the anechoic chamber, sound is absorbed by hundreds of custom-designed fiberglass wedges covering the walls, floor, and ceiling. The reverberation room uses standard building materials and is constructed with very rigid walls to increase sound reflections.

As part of the project, a headset is being tested to determine the extent of the device’s ability to reduce outside noise while improving speech intelligibility, explains co-investigator Donald Peterson, director of the Biodynamics Lab.