Immersion in water below 70°F (21°C) poses an immediate threat to survival due to rapid heat loss, which can lead to hypothermia and unconsciousness. Strategic body positioning is a non-negotiable survival technique for anyone unexpectedly submerged. Adopting a specific posture is the single most effective way to extend the time available for rescue.
Understanding Rapid Heat Loss in Water
The primary reason cold water is dangerous is the physical mechanism of heat transfer known as conduction. Water removes heat from the body up to 25 times faster than air of the same temperature because it is denser and has a higher specific heat capacity. This allows water to draw and absorb a greater amount of thermal energy from the body’s surface.
Rapid heat loss is concentrated in specific areas where major arteries run close to the skin. These high-loss areas include the head and neck, which can account for 40 to 45 percent of total heat loss, along with the armpits, sides of the chest, and the groin area. If a person moves or attempts to swim, the rate of heat loss increases further. This convective heat loss accelerates the drop in core body temperature, which is why unnecessary movement should be strictly avoided. The speed of this cooling process underscores the necessity of immediately reducing the amount of exposed skin area.
The Primary Goal of the Heat Escape Lessening Posture
The main reason for assuming the Heat Escape Lessening Posture (HELP) is to maximize the retention of core body heat. By reducing the total surface area exposed to the cold water, the posture significantly slows the rate at which the core temperature drops. Research shows this technique can reduce the rate of body cooling by approximately one-third, effectively extending survival time.
The HELP position is a fetal-like posture that uses the body’s limbs to shield high heat loss zones. The arms are pressed tightly against the sides of the chest, covering the lateral ribcage and armpits, which are areas with minimal insulating fat. Simultaneously, the knees are drawn up toward the chest to protect the groin area. The groin is highly vascularized, containing major blood vessels that quickly transfer heat when exposed. Tucking the legs creates a protective barrier, minimizing the circulation of cold water over these vulnerable spots.
Performing the Position and Group Alternatives
Executing the HELP position requires the person to be wearing a Personal Flotation Device (PFD) or life jacket, which provides the necessary buoyancy without expending energy.
Performing the HELP Position
- Cross arms tightly against the chest.
- Tuck hands flat under the armpits to shield the sides of the torso.
- Bring the knees up to the chest as close as possible to create a barrier for the groin area.
- If a full tuck is difficult, cross the calves and keep the knees bent and close to the body.
Group Alternatives
When multiple people are immersed together, the solitary HELP technique is replaced by the Huddle Position. This alternative shares the goal of heat conservation but applies it in a group context. Individuals link arms over each other’s shoulders or backs and pull their chests close together, facing inward in a circle. The Huddle position reduces the overall surface area exposed to the water and allows individuals to share residual body heat. Children or smaller individuals should be positioned in the center of the circle for maximum protection. Both the HELP and Huddle positions are passive survival strategies designed for waiting for rescue.