Citation

Malcolm S, Armstrong R, Michaliades M, Green R. Int. J. Ind. Ergonomics 2000; 26(3): 417-424.

Copyright

(Copyright © 2000, Elsevier Publishing)

DOI

unavailable

PMID

unavailable

Abstract

The purpose of the present study was to examine the physiological and psychophysical response to walking in simulated tropical conditions while wearing two designs of wet weather jackets (WWJ) and no WWJ. Ten Regular Army personnel walked for 60 min at 5 m min-1 at 35[deg]C, 95% relative humidity with simulated warm (22[deg]C) rain falling. In the no WWJ condition subjects wore a standard disruptive pattern camouflage uniform (DPCU). WWJ designs included a poncho (P) and a three-quarter length jacket (J) worn over DPCU. Subjects completed six trials; one in each clothing condition in both a wind and no wind condition. Wind had no effect on any parameter measured. Heart rate (HR), rectal temperature (Tre) and mean skin temperature (Tsk) were significantly lower (pTre was significantly higher in P compared with J and DPCU. Tsk dropped in DPCU and increased 1.5[deg]C and 2.15[deg]C wearing J and P, respectively. General body thermal comfort was reported as slightly warm, warm and hot for DPCU, J and P, respectively. Voluntary water consumption and sweat losses were significantly greater in WWJs than in DPCU. These data indicate that wearing any form of WWJ during physical activity in tropical conditions significantly impairs heat loss and increases physiological stress and that a poncho restricts heat loss more than a jacket design.Relevance to industryAustralian soldiers may be required to perform prolonged activity in tropical conditions. It is important that soldiers be supplied with wet weather jackets which offer protection while still allowing for heat loss. This study has shown that during physical activity in tropical conditions, any design of wet weather garment worn over a standard uniform will impair heat loss and increase physiological stress.