Warfighter auditory situation awareness: Effects of augmented hearing protection/enhancement devices and TCAPS for military ground combat applications

Objective: To determine the effects of current hearing protection/enhancement devices (HPEDs) and tactical communications and protection systems (TCAPS) on auditory detection and identification of three critical military signals associated with potential threats. Design: Utilizing a 6 x 3 within-subject experimental design, 24 normal-hearing Virginia Tech Reserve Officer Training Corps (ROTC) cadets and active duty soldiers participated. Study sample: Five HPEDS and TCAP devices plus the open ear were tested. On each trial, either wearing a device or with open ears, subjects walked along a 3000-foot line of discrete distance markers toward the auditory threat, which was not visible but still within line-of-sight over flat terrain, stopping to listen when instructed. On approach to the threat, the linear distance at first detection was measured, followed by a continued approach until positive identification occurred. Then the subject reversed direction, retreating away from the threat until detection was lost. Results: ANOVA and post hoc tests were applied to determine statistically-significant differences among HPEDs, TCAPS, and the open ear on the objective detection and identification distance measures. Conclusions: The results have serious implications for selection of HPDs, HPEDs, and TCAPS for applications where preservation of auditory situational awareness via the fundamental detection and identification tasks are essential.