Evaluation of Auditory Characteristics of Communications and Hearing Protection Systems (C&HPSs) Part I - Sound Attenuation to Low-Intensity Sounds

Report No. ARL-TR-5050
Authors: Paula Henry; Rachel Weatherless
Date/Pages: January 2010; 20 pages
Abstract: Devices that provide hearing protection, situational awareness, and radio communications are often referred to as Communications and Hearing Protection Systems (C&HPSs). Soldiers use these systems while deployed to navigate within their environment, communicate with their team members, and protect their hearing. Each of the three features of select C&HPSs (hearing protection, speech communication, and situational awareness) was evaluated by the U.S. Army Research Laboratory in order to obtain data that is independent from that provided by the manufacturer. This report is the first in a series of three reports and focuses on the sound attenuation obtained from three commercially available C&HPSs: Sennheiser SLC 110, Nacre QuietPro, and Silynx QuietOps. Real-ear attenuation at threshold values were obtained for 12 listeners with each of the three systems. The results showed that the Nacre QuietPro provided the greatest amount of attenuation for low-intensity sounds followed by the Silynx QuietOps. The Sennheiser SLC-110 provided the least amount of attenuation and the greatest variability across participants. The general pattern of attenuation provided across stimulus frequencies was similar for all three devices.
Distribution: Approved for public release
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Last Update / Reviewed: January 1, 2010