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Exercising divers' thermal protection as a function of water temperature
David R Pendergast1, Joseph Mollendorf
1Center for Research and Education in Special Environments, University at Buffalo, Buffalo, NY, USA. dpenderg@buffalo.edu
Summary
Divers require active thermal protection in varying water temperatures. A self-contained diver thermal protection system (DTPS) maintained divers
Area of Science:
- Diving Physiology
- Thermal Regulation
- Protective Systems
Background:
- Passive thermal insulation and physiological adjustments are insufficient for diver thermal protection.
- Sport, professional, and military divers face extreme water temperatures.
- Previous studies utilized actively heated/cooled water suits for resting subjects.
Purpose of the Study:
- To evaluate the effectiveness of a self-contained diver thermal protection system (DTPS) in maintaining diver thermal comfort.
- To assess diver thermal regulation in a range of water temperatures (10°C–39°C).
- To quantify the heating/cooling power requirements of the DTPS across different water temperatures.
Main Methods:
- Eight male divers wore a 6-mm foam neoprene wetsuit and were tested with the DTPS operational and off.
- Skin and core temperatures were monitored over 90-minute exposures in water depths of 4 feet.
- The DTPS, comprising thermoelectric devices, pumps, and a controller, circulated water through a six-zone tube suit.
Main Results:
- Unprotected divers experienced significant decreases in skin and core temperatures, approaching water temperature.
- The DTPS maintained skin and core temperatures within acceptable limits across all tested water temperatures.
- Mean skin temperature showed a strong correlation with water temperature when unprotected (T(S) = 0.44 T(W) + 21.23°C) but was moderated when protected (T(S) = 0.19 T(W) + 27.1°C).
Conclusions:
- The self-contained diver thermal protection system (DTPS) effectively protects divers from thermal stress in both cold and warm waters.
- Divers reported comfort and maintained acceptable physiological temperatures when utilizing the DTPS.
- The DTPS is crucial for ensuring diver safety and performance across a wide spectrum of operational water conditions.
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