Thermal Physiological Consideration of Precooling Procedures in Manned Space Craft / 航天医学与医学工程

ABSTRACT

Objective To explore a space craft precooling temperature at which excessive thermal stress on the crew member could be prevented or reduced in an overheated launch or reentry module. Method Five young male volunteers wearing a space suit participated in 25 tests at sea level.The space suit was either ventilated in a volume air flow rate of 100 L/min (STPD) with ambient air at temperatures (Ta) of 15℃,10℃,and 5℃,respectively,or not ventilated. Rectal (Tr),mean skin (Tsk) and mean body (Tb) temperatures were measured. Result At Ta 15℃,Tr decreased without significance (from 37.0±0.2℃to 36.7±0.3℃) in 120-min tests,whereas Tsk and Tb decreased significantly,and subjects had local cold strain whether the space suit was ventilated or not; while at Ta 10℃,Tr decreased from 37.0±0.3℃ to 36.3±0.3℃(P<0.05),subjects had a whole body cold strain,and both Tsk and Tb dropped continuously and significantly. Conclusion Ambient temperature 15℃,at which the thermal comfort states of crew was not significantly degraded,was acceptable after precooling in a space craft.