TM 5-852-4/AFM 88-19, Chap. 4
Table 1-1. Stages of Relative Human Comfort and the Environmental Effects of Atmospheric Cooling.
Effects of Atmospheric Cooling.
Wind chill factor (kg cal/m hr)
Conditions considered as comfortable when
men are dressed in wool underwear, socks,
mitts, ski boots, ski headband, and thin
cotton windbreaker suits, and while skiing
over snow at about 3 mph (metabolic
output about 200 kg cal/m hr).
Pleasant conditions for travel cease on foggy
and overcast days.
Pleasant conditions for travel cease on clear
Freezing of human flesh begins, depending
upon the degree of activity, the amount of
skin and circulation.
Travel and life in temporary shelter very
Conditions reached in the darkness of mid-
winter. Exposed areas of face freeze within
less than a minute for the average
individual. Travel dangerous.
Exposed areas of the face freeze within less
than 1/2 minute for the average individual.