On diver thermal status and susceptibility to decompression sickness

Area of Science:

• Diving Physiology
• Hyperbaric Medicine
• Risk Management in Diving

Background:

• The study clarifies previous findings on diver thermal status and decompression sickness (DCS) risk, addressing a Letter to the Editor.
• The research tested extreme thermal conditions to identify effects on DCS susceptibility, not typical operational dives.

Discussion:

• Optimal thermal strategy involves remaining cool during gas uptake (bottom phase) and warm during off-gassing (decompression).
• Observed thermal effects on DCS risk are presumed to vary monotonically with temperature and duration, even under less extreme conditions.
• Thermal effects on DCS are qualitatively similar across various depths and are applicable to recreational and technical diving.

Key Insights:

• Chilling on the bottom phase decreases DCS susceptibility.
• Chilling during decompression increases DCS susceptibility.
• Diver thermal status significantly impacts DCS risk, regardless of available technology.

Outlook:

• While magnitudes may vary, the direction of thermal effects on DCS risk is consistent.
• Divers should limit active heating on bottom and increase it during decompression, avoiding heat stress.
• Understanding these thermal effects is crucial for optimizing dive safety and minimizing decompression obligations.