Thermal Homeostasis of Resting Man in Helium-Oxygen at 1-50 Atmospheres Absolute.

摘要

Spaur (1974) showed that man can work effectively and live comfortably for 7 days in helium-oxygen at 49.5 ATA, a pressure equivalent to 1600 ft (488 m) sea water. Two of his six male subjects were studied during habitation at and decompression from this pressure, in hyperbaric chambers with an O2 pressure of 0.30-0.35 ATA. To avoid thermal stress during the 32 day exposure, ambient temperature was maintained at 30-32 C (86-89 F). Relative humidity was 68-74%, and there was no measurable velocity. Comfort and thermal balance were adequate during mild activity when the men wore swim trunks and cotton jersey shirts. When they were seated without shirts, their rectal temperature fell during 2-hr observation periods at depths greater than 800 fsw, while skin temperature and oxygen consumption remained normal, and scrotal temperature increased. The fall in rectal temperature during rest appeared to be due more to skin convection than to respiratory heat loss, and the coefficient of cutaneous convection could be expressed in a form similar to that suggested by Varene, et al. (1972).