Physiological and perceptual responses due to accidental water immersion

With the increasing global civil aviation business, water-related accidents in airplanes, often accompanied by accidental passenger waterfalls, are inevitable. Exposure to cold water can cause physiological and perceptual abnormalities that may endanger human health and safety. In this study, a water tank was constructed in a climate chamber to simulate accidental water immersion, and 10 healthy male subjects were recruited to investigate physiological and perceptual responses during air exposure and water immersion. Parameters such as core temperature, skin temperature, metabolic heat production, blood oxygen saturation, heart rate, respiratory rate, thermal sensation, thermal acceptance, and thermal comfort were continuously monitored. Statistical analysis revealed that skin temperature, metabolic heat production, and heart rate were the most sensitive parameters during water immersion. Changes in skin temperature were smallest in the leg (DTs ≈ 4 °C) and largest in the chest (DTs ≈ 9 °C) upon water immersion. There was a strong correlation between local thermal sensation and local skin temperature when subjects remained sedentary (R2 > 0.8). The use of a LP2 (life preserver, 0.20 clo) slightly improved local thermal comfort compared to LP1 (0.05 clo), suggesting that life preserver may compensate for the decrease in thermal comfort caused by immersion in water.