Body cooling with ice for warm-water diving operations

Physiologic responses were measured on 2 professional divers exposed to a simulated repair work submersed for 60 min in water at temperatures of 34 degrees, 38 degrees, and 42 degrees C. Exposures were repeated with two types of diving suits; a normal dry, rubber suit (NDS) and this suit worn over an ice-cooled vest (ICEDS). Heat balance (lower heat storage) was better maintained at all temperatures with ICEDS. Physiologic strain was significant with NDS in 38 degrees C. At 42 degrees C 1 subject was able to complete 60 min with ICEDS. However, all exposures at 42 degrees C caused an extremely high physiologic strain, more so with NDS. Tolerance times observed were in good agreement with suggested criteria for heat tolerance. An ice-cooled vest, with room for further improvement, allows for at least 15-30 min longer exposure periods in the studied temperature range.