4. Encountering an obstacle
WRONG: Press on at all costs. This is your one shot!
RIGHT: Carefully assess the risk before you try to get past it. Ask yourself: What’s the worst thing that could happen if I attempt this? If the answer is unacceptable, don’t proceed. “Make decisions conservatively, with the idea that you can always come back and do it when the conditions are better,” suggests Anderson.
Rushing river: Turn back if the water is more than knee-deep, you can hear rocks tumbling underwater, or there are hazards (such as downed trees, boulders, or a waterfall) downstream.
Exposed scramble: Avoid wet, mossy, or loose rocks, and never ascend anything you don’t think you can downclimb. Climb without a rope only if doing so requires easy moves, and test each hold before putting your full weight on it.
Snow slope: Retreat if the snow is too hard to kick steps in (or wait for the sun to soften it). Be alert in areas with avalanche potential (generally, 30- to 55-degree slopes), especially after storms, when high winds can create unstable snow layers.
How to cross a river
Keep boots dry by crossing in sandals or sneakers. Unbuckle your pack’s hipbelt and sternum straps. Facing upstream, slowly sidestep across, leaning into the current and angling slightly downstream. Use trekking poles or sticks for balance. If water is swift, link arms with a partner or form a tripod shape with two others.
How to traverse a snow slope
When ascending, make a platform for your foot by kicking steps into the snow before you step forward. Switchback up steep slopes and plant a trekking pole or stick in front of you with each stride for balance. Dig into the snow with your heels on the way down.
How to spot avalanche hazard
Look out for leeward slopes, cornices, and gullies that can funnel snow. Avoid areas that show signs of previous slides, such as knocked-down trees. Evaluate slopes using the ruler on your compass and a 7.5-minute topo: If two or more contour lines appear within one-sixteenth of an inch, the slope exceeds 33 degrees.
5. Recognizing a problem
WRONG: Ignore the early signals of serious conditions–like hypothermia, heat exhaustion, or altitude sickness–and hike on. You’ll probably be fine, and it’s just a few miles to camp.
RIGHT: Know the warning signs of outdoor illnesses and stop to administer first aid as soon as they appear. Continuing to travel will just make things worse, and will impair your ability to deal safely with any challenges ahead.
Hypothermia: Watch for shivering, loss of coordination, confusion, numbness, and apathy.
Heat exhaustion: Look out for thirst, heavy sweating, flushed skin, a rapid pulse, nausea, and a headache.
Altitude sickness: Early signs include headache, appetite loss, nausea, fatigue, dizziness, and irritability (typically above 8,000 feet).