What is the primary risk during the initial immersion phase in cold water?

During the initial immersion phase in cold water, the primary risk is gasping and possible drowning. When a person suddenly enters cold water, the body's immediate response can trigger an involuntary gasp reflex, which may lead to inhalation of water if the individual is submerged or close to the water's surface. This reflex can occur rapidly and without warning, increasing the risk of drowning, especially for those who might not be prepared for the shock of cold water.

The physiological effects of cold water immersion also contribute to this risk. The cold induces a sudden increase in heart rate and blood pressure, and can cause a sense of panic, making it difficult for a person to think clearly or to coordinate their movements for escape. Acknowledging this severe and immediate threat is critical for anyone entering cold environments, particularly for those involved in water activities or safety enforcement.