Table 1.

Physiological criteria for cold injury prevention and for thermal performance metrics of cold weather ensembles

Thermal performance metrics	Physiological parameters	Criteria	Signs and symptoms
Functional time	Core temperature	36°C	Mild hypothermia
Hand endurance time	Finger skin temperature	5°C	Extreme pain or numbness Significant impairment in manual dexterity
Foot endurance time	Toe skin temperature	5°C	Extreme pain or numbness
Exposed skin endurance time	Exposed skin temperature	5°C	Extreme pain or numbness
Comfort time	Skin wettedness	0.5	Discomfort, skin and underwear getting wet