If you're stranded outdoors during a blizzard, knowing how to build a snow cave can spell the difference between life and death.
: Because a cave-in could be deadly, snow caves should be built in emergencies only.
Step 1: Stay calm Stay calm! Panic won’t help you survive.
Step 2: Find a snowdrift Find a snowdrift that will be deep enough to tunnel a hole large enough to lay in and with walls that are at least a foot thick for adequate insulation. If you can’t find a drift large enough, you can pack your own pile.
TIP: Create a cold trap You must be able to pack the snow to reduce the threat of a cave-in—if you can’t make a firm snowball, you can’t make a snow cave.
Step 3: Tunnel an entrance Determine which way the wind is blowing, and tunnel an entrance into the drift on the side that’s facing away from it.
Step 4: Create a cold trap Because heat rises, you’ll want the entrance of your cave to be lower than the part where you’ll lay. Dig an impression in the entrance to trap the cold air.
Step 5: Create a heat trap Continue burrowing into the drift so that the main portion of the cave is about a foot higher off the ground than the entrance, creating a heat trap.
TIP: A snow cave is not an igloo—it just needs to be big enough for you to get in and out of and lie in, not walk around or even fully sit up.
Step 6: Ventilate the roof Use a stick or other pointy object to create two holes several feet apart in the roof for ventilation. Poke them from the outside of the cave if you need to—just make sure they pierce the cave so fresh air can get in.
Step 7: Dig moisture grooves Dig small grooves in the floor of the cave to drain any moisture caused by your body heat. If the cave gets damp, it will just make you colder.
Step 8: Mark the outside Mark the outside of the snow cave with some of your belongings so rescuers can find you. If it’s still snowing heavily, try to put them in a place they’re not as likely to be buried, like hanging from a nearby tree.
Step 9: Get in When your cave is big and stable enough, get in so you’re resting in the upper level. Reach below and pack snow in the entrance to close yourself in and block out the wind.
Step 10: Stay put Don’t leave your shelter until the storm stops or help arrives.
FACT: Mountain climbers trapped in storms have survived in snow caves for as long as 13 days.