Operational Preventive Medicine (PMT 110) Practice Test

Cold stress happens when the body loses heat faster than it can generate it. The most direct driver of that heat loss is the surrounding air temperature. When air is cold, the gradient between the body's heat and the environment increases, so heat flows out more quickly, raising the risk of hypothermia and other cold-related problems. While other factors like wind speed and humidity can amplify cooling—wind removes warmed air near the skin, and damp conditions increase evaporative heat loss—the ambient air temperature sets the primary level of heat loss the body has to contend with. Field situation also matters because duration of exposure and clothing choices affect how much heat is retained, but the actual temperature of the air is the fundamental contributor to cold stress.