Shelter and body temperature

This is general first-aid information, not medical advice. Get trained help as soon as you can; in an emergency call your local emergency number.

Cold, wet and wind kill more people outdoors than hunger. A shelter's job is to keep you dry, out of the wind and off the cold ground.

Where to shelter

• Flat, dry ground, out of the wind.
• Not in dry stream beds (flash floods), under dead trees or branches ("widow-makers"), at the foot of steep slopes, or on hilltops in a thunderstorm.
• Near water and firewood, but not right beside the water: cold air and insects collect there.
• Somewhere rescuers can see, or mark it with a signal. See Signalling.

Fast shelters

• Vehicle: usually the best shelter you have. Stay with it.
• Tarp or emergency blanket lean-to: tie a ridgeline between two trees, drape the tarp at an angle with the low side to the wind.
• Debris hut: a ridgepole propped on a stump, ribbed with sticks, then piled with at least 2 to 3 feet (60 to 90 cm) of dry leaves. Stuff the inside with more leaves. Small is warm.
• Snow: a trench or cave insulates well, but needs a vent hole and takes hours of work. Stay as dry as possible while digging.

Insulate from the ground

The ground pulls heat out of you faster than the air. Lie on a pad, a pack, pine boughs or at least 4 inches (10 cm) of dry leaves.

Hypothermia

Signs: shivering, fumbling hands, slurred speech, confusion, sleepiness. Shivering may stop as it gets worse.

1. Get the person out of the wind and wet.
2. Remove wet clothing; replace with dry layers and a hat.
3. Insulate them from the ground and wrap them, including the head.
4. Warm the core (chest, neck, armpits, groin) with warm, not hot, packs, or with your own body inside a shared sleeping bag.
5. Give warm, sweet drinks only if they are fully awake and can swallow.
6. Handle severe cases gently and get medical help.

Heat illness

Heat exhaustion (heavy sweat, weakness, nausea): move to shade, loosen clothing, cool with wet cloths, sip water. Heat stroke (hot skin, confusion, collapse) is an emergency: cool them fast with water and fanning, and get help.

Sources

• CDC: Preventing cold-related illness (US government, public domain)
• CDC: Heat-related illness signs and symptoms (US government, public domain)
• US Army Techniques Publication ATP 3-50.21, Survival, chapter on shelters (US government work, public domain)