What is the main risk during stage 3 of cold water immersion?

During stage 3 of cold water immersion, the main risk is long-term immersion hypothermia. At this stage, a person has typically been in cold water for an extended period, leading to a significant decrease in body temperature. As hypothermia progresses, it severely affects the body's ability to function, including vital systems like the heart and brain, which can result in confusion, loss of coordination, and ultimately can be life-threatening.

Long-term immersion hypothermia occurs because the body loses heat much faster in cold water compared to cold air due to the greater thermal conductivity of water. This stage is critical because it can escalate quickly, and victims may become unable to self-rescue or signal for help as their cognitive functions decline. Being aware of this risk emphasizes the importance of rapid intervention and rescue efforts in cold water situations, as the longer someone is immersed in cold water, the higher the likelihood of severe hypothermia setting in. Understanding this can help individuals prepare better for boating or activities in cold water environments.