Tri-Service Perspectives on Microclimate Cooling of Protective Clothing in the Heat.

Abstract : This Tri-Service report evaluates the effectiveness of various microclimate cooling systems in alleviating the thermal burden imposed on our service members by wearing protective clothing in the heat. The report summarizes the findings from studies involving liquid-cooled, air-cooled, and ice-cooled systems conducted by the U.S. Army, U.S. Navy, and the U.S. Air Force. While both liquid- and air-cooled systems are shown to remove significant quantities of body heat, more evidence seems to favor air-cooled systems. In general, most commercially available microclimate cooling systems are shown not to be operationally suitable for the Services' needs. To date, the ideal microclimate cooling system suitable for most military situations has not been developed or identified. However, prediction modeling analyses indicate that with heat extraction rates of 300-400 watt, microclimate cooling can be a significant force multiplier for the Services in most desert and tropic climates.