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A newsletter dedicated to keeping attorneys informed of the technical side of product liability cases.

Issue 67: June/July 2017

Climbing Accidents 2017

By John L. Ryan, P.E.

© 2017 M.A.S.E. LLC


Rock climbing is a sport that has been around for decades, and has become increasingly popular. More people are getting into this exciting sport, which is resulting in greater accidents, and people seeking answers to how these accidents occurred, and the big question—who is responsible?

Climbing Gyms

With the increased popularity of climbing has come climbing gyms popping up all over the country. These facilities can be excellent ways for people to get exposed to the sport, learn the basics, and train. While there are many positive aspects of climbing gyms, there seems to be more accidents occurring at gyms, as well as outdoors at climbing crags. Some of this is simply due to increased number of climbers, but there is concern that people learning how to climb in a gym may not be learning the skills they need to be safe. The casual, social aspect of climbing gyms along with many distractions may also contribute to a sense of complacency, both indoors and out.

Modes of failure

So how do climbers get dropped, or fall to the ground? Modern free climbing involves ropes and hardware that is designed to prevent accidents and injury if a climber falls. If a climber hits the ground, something has gone terribly wrong. This is in stark contrast to people who climb without a rope, such as the media sensation Alex Honnold, who have no back up, and if they fall due to fatigue, or a hand or foot hold breaking, there is nothing to prevent them from hitting the ground. The technical term for this is free soloing. I am going to review some basic categories of failures that can result in a dropped climber.

Belayer Error

Standard roped climbing consists of a climber, and a belayer, who uses a friction device to help hold the climber if the climber falls, and to lower the climber as needed. This is not a failsafe situation with standard belay devices, and people do get dropped, when belayers do not use proper technique, or let go of the braking side of the rope, before or during a fall. A rope burn on the belayer’s hand indicates the belayer grabbed the rope after it started to move, or an incorrectly loaded belay device. This is a common failure mode.

Rappel Accidents

Rappelling is the one time that a climber’s safety is entirely reliant upon the safety system. An error here results in death or serious injury. Common failure modes include rappelling off of the end of the rope before safely on the ground, incorrect rappel device configuration, loss of control of rappel, or due to a fatal error in a simultaneous rappel.

Catastrophic gear failure

While it doesn’t happen often, occasionally catastrophic gear failure occurs in a fall. There are typically influencing variables such as a rope running across a sharp rock edge during a long or pendulum fall, or a carabiner getting loaded in a direction not intended by the manufacturer (crossloading). At times there are design or manufacturing defects that can result in gear failure, and any catastrophic gear failure analysis should consider this as a possibility.

Hard falls can overload rope fibers as seen in this rope subjected to a live factor 2 fall, but rarely results in catastrophic failure of the entire rope.

Unfinished Tie-In Knot

Distractions and complacency can result in a climber not finishing the tie-in knot, which could have devastating effects. There is some redundancy built into the standard Figure 8 Follow Through tie-in knot. The author had the tail of a rope pull through the first part of the tie-in knot in a fall, but the knot still held.

Belay device ‘failure’

There are many belay devices on the market that attempt to provide a back-up to the human factor of the belaying process. These devices are called assisted belay or autoblock devices. The intent of these devices is to prevent the rope from slipping, and thus the climber from falling, even if the belayer is not holding the rope. While this has introduced a redundancy into a high risk system, some of these devices introduce new failure modes including the assisted belay function failing if the climber’s side of the rope is grabbed by the belayer. This can be a reflexive action by a belayer who is briefly giving out or taking in slack.

Rappelling vs. Lowering Communication Failure Accidents

Another huge category of climbing-related injuries and deaths is due to a communication breakdown between the belayer and climber after the lead climber has reached the anchors of a climb. When a climber reaches the end of a climb, there must be a transition from using the climber’s personal gear to the permanent anchor on the rock, so that no personal gear is left behind. There are two distinct methods of doing this—the climber comes off belay, and rappels to the ground, or the climber is lowered to the ground by the belayer after threading the rope through the anchor and retying. If the lead climber thinks that the belayer is going to lower the climber, but the belayer thinks the climber is rappelling, the belayer takes the climber off belay, and the climber weights the rope thinking the belayer is in control, instead the climber falls to the ground. Interestingly, from a risk analysis viewpoint, choosing to lower off a climb introduces the distinct hazard of miscommunication leading to death. If a climber is rappelling, but the belayer thinks that the climber will be lowered, there is no additional hazard.

Rappeling and lowering both fully load, and rely upon, the rope, harness, anchoring system, and belay device.

How We Can Help

At MASE, we have expertise in determining if a climbing accident is due to belayer error, climber mistake, gear failure, communication failure, or other cause. Mechanical and Safety Engineering owner John L. Ryan, P.E. has been rock climbing since 1992 and has experience in rock climbing accident investigation. This experience helps him identify responsibility in a culture of risk. When your client is wanting answers, we can help. Call us at (855) 627-6273 or email us at


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© 2017 Mechanical and Safety Engineering