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Rock! Prevent Rockfall and Calmly Handle Emergencies

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Yosemite’s El Capitan claimed two climbers’ lives in a two-week span in late May and early June. Both incidents involved falling rock, but causes and effects in each scenario were quite different. Even if you’re the safest and smartest climber in the world, climbing is a dangerous sport, and it exposes you to a number of things out of your control, including rockfall. No one can predict with certainty when this will happen or what harm it might cause, but we talked to Yosemite climbing ranger Ben Doyle and Yosemite Valley District Ranger Jack Hoeflich about what we can do to mitigate rockfall and what to do in an emergency.


Who: Mason Robison, 38; Felix Joseph Kiernan, 28

Where:Muir Wall, El Cap, Yosemite; East Buttress, El Cap, Yosemite

When: May 19, 2013; June 2, 2013

What happened: Robison was on the 27th pitch of the 33-pitch Muir Wall (5.10 A2) when he pulled off a large block, which severed his lead line. He then fell to the end of his haul line, where he died upon impact.

Kiernan was belaying about 600 feet up the East Buttress (5.10b) when his partner above him dislodged a rock that measured 1′ x 2′. The rock hurtled down 150 feet before it hit Kiernan. He died instantly.


“Spontaneous rockfall is not the problem; all the fatal and serious accidents were triggered by the victim, the rope, or by climbers above,” wrote original Yosemite Search and Rescue member (since 1974) John Dill in “Staying Alive,” a report released in 2000 that examined climbing accidents in Yosemite. While rockfall is not predictable, here are steps you can take to manage risk.

  • Know the route and the condition it’s in; plan ahead and prepare for it. Pore over topos and trip reports from SuperTopo ( and Mountain Project (

  • Shoulder seasons (spring and fall) are particularly dangerous because many areas experience freeze-thaw cycles, where the temperature fluctuates above and below the freezing point. Repeated freezing and thawing significantly weakens the rock and causes it to break and split along joints and other existing weaknesses.

  • Pay attention to where your rope is and what it’s contacting at all times—while leading, following, and rappelling. Ropes are an all-too-common cause of rocks coming down.

  • Be aware of loose rock by continuously assessing the holds you’re pulling on. Ask yourself, “Does this look detached?” If it does—or you have any suspicions—knock on it. Listen for sounds that indicate hollowness; they can be high-pitched or low-pitched. If you’re knocking on solid rock, it will make almost no sound. See below for what to do if it is hollow.

  • Next question: “Does it move or flex at all?” Some flakes (like the one on Muir Wall) can be attached on one end but not the other. Remember, this is an open-ended assessment, so there’s no right or wrong answer. Use your experience, climbing mileage, and judgment to make a discretionary call.

  • If you detect weakness, avoid touching the rock. If you absolutely must pull on it, pull down—NOT out. Pulling out is more likely to dislodge the rock. Pushing on rocks (stemming, manteling, smearing) is less dangerous, too, as it will push the block into position rather than pull it out.

Even if you follow all the recommended steps, accidents still happen. If something does occur, the first step is to get control of yourself if you are freaking out. Take long, deep breaths (short, quick breaths will exacerbate the panic response) until your mind settles and you can think clearly, and then size up the scene: Are you safe? Do you have any injuries? Are you attached to the wall and out of harm’s way? Get yourself safe first by anchoring into the wall with whatever gear you have, and then assess your partner. If it’s serious enough to need help, alert the authorities. Doyle and Hoeflich recommend always carrying a fully charged cell phone, leaving it turned off until you need it. In many places, including the Valley, you can get cell service to call 911.

If you don’t have a cell phone, get the attention of other climbers and people below the old-fashioned way: Yell “Help!” repeatedly as loud as you can. Make yourself visible by waving something colorful like a jacket, or use a headlamp to flash light. A lot of emergency calls that Doyle and Hoeflich have received originated from someone else hearing shouting and calling it in. Another option is to carry a small two-way radio, which big wallers sometimes do for easier communication from the top of a pitch to the bottom. Scroll through the channels to find one that people are using, and ask them to call for help.

Ben Doyle has 20 ascents of El Cap under his belt, as well as five seasons with Yosemite Search and Rescue. In April 2013, he achieved his longtime goal of climbing the Nose of El Capitan and Regular Northwest Face of Half Dome in a day.