Comparison of a military chemical suit and an industrial usage vapor barrier suit across two thermal environments.

Abstract

This study compared physiological responses to wearing military chemical protective clothing (MPC) and industrial vapor barrier protective clothing (IPC) across two thermal environments to determine the application of the MPC research toward IPC use. Ten males wore each ensemble in a wet bulb globe temperature (WBGT) = 18 and 26 degrees C environment for four test sessions. Each test session consisted of two 30-min work bouts separated by a 30-min recovery period. Each work bout consisted of walking on a treadmill with an oxygen demand of 1.4 L/min for 15 min followed by 7 min of arm curling of 0.9 L/min, followed by 8 min of walking. Work was stopped when either the 30-min time limit was met or a core temperature (Tre) of 38 degrees C was achieved. Variables included sweat rate, heart rate at the end of each work bout, change in (delta) Tre and mean skin temperature (mTsk), and heat stored (Whr). A repeated measures analysis of variance showed no significant difference (p > 0.05) between heart rates at the end of the work bouts between the MPC and IPC. A significant difference was found (p < 0.05) between sweat rates (MPC = 11.5, IPC = 7.4 g/min), delta mTsk, and heat stored, all independent of WBGT. A significant difference (p < 0.05) was also found between delta Tre (MPC = 0.52, IPC = 0.90) in the WBGT = 26 degrees C environment. Results indicate that these two suits elicit similar physiological responses in a cool environment (WBGT = 1 degrees C) but different Tre responses in a hot (WBGT = 26 degrees C) environment. Results show that MPC research can be applied toward IPC settings; however, comparisons between the two should be made with caution, particularly in regard to hot environments.