Endurance Time in the Self-Contained Toxic Environment Protective Outfit (STEPO) with Personal Ice-Cooled Microclimate Cooling System (PICS) in Three Environments.

Abstract

This study of the Self-Contained Toxic Environment Protective Ouffit (STEPO) with the Personal Ice-Cooled Microclimate Cooling System (PICS) in three environments was conducted in September 2002 at the request of Project Manager - Soldier Systems, Product Manager- Soldier Equipment (PM-Soldier), Ft. Belvoir, VA. PM-Soldier was addressing the needs of the STEPO/PICS users for guidance on work times up to 4 hours. A 1999 study of this STEPO/PICS system demonstrated that 4-hr work times were not safe for workers in a 38 deg C (100 deg F) environment. Using the same testing format of repeated cycles of 10 min rest and 20 min of treadmill walking, eliciting an overall moderate energy cost of 300-350 Watts, this study looked at the system in three less stressful environments: HOT 32.2 deg C (90 deg F) / 30% rh MODERATE 23.9 deg C (75 deg F) /40% rh, and COOL 15.6 deg C (60 deg F) / 50% rh, to ascertain endurance times in each of these environments.