What is the maximum time for cold immersion before long-term hypothermia sets in?

Long-term hypothermia can set in within a relatively short period of cold immersion, particularly in cold water where the body loses heat much faster than in cool air. The correct time frame for the onset of long-term hypothermia is around 30 minutes, depending on various factors such as water temperature, the individual's body composition, and their level of physical exertion.

At lower temperatures, the body's ability to regulate its core temperature diminishes, and vital organs begin to lose functionality. Beyond this timeframe, a person’s risk of significant hypothermia increases markedly, leading to life-threatening effects. Being aware of these timeframes is crucial for safety in outdoor activities and for rescue situations. Understanding this risk assists game wardens and others involved in outdoor recreation or emergency response to make informed decisions quickly during cold water exposure scenarios.