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Harness Failure—California, Practice Cliffs

HARNESS FAILURE—California, Practice Cliffs. A Mountain Safety Research climbing harness broke at the anchor point when the belayer caught a simulated leader fall at the Rock Climbing Sections safety tests May 24. Dave Perkins was anchored to a tree at ground level, with a carabiner joining his harness to a sling. When he caught the weight of the “bucket” fall, he flew through the air as if propelled by a catapult. The incident was observed and the harness examined by members of the RCS Safety Committee who were giving the tests. The harness had parted where it went over the carabiner.

The harness was made of MSR 2 inch black “Polypro,” which is sold through the MSR (Penberthy) catalogue in two forms: either as a pre-sewn harness, or for the climber to tie his own. It is described in the 1975 MSR catalogue as a “light comfortable harness for general rock and glacier climbing. Design tested by ten drops of a 220-lb. torso dummy at shock forces of 1200-2800 lbs.” (The RCS “bucket” used for practice in holding leader falls weighs about 80 lbs. and is dropped with varying amounts of slack in the rope. Although old ropes are always used, no other equipment failure has ever been reported). MSR’s 1976 catalogue adds, “Intended for average climbing.”

Dave’s harness was two years old, but had never suffered the shock of a fall, or any stress beyond being clipped to a chest loop in prusiking. His model was self-tied. Another belayer also holding simulated leader falls was wearing a pre-sewn model of the same material. Hers was partly torn by the end of the exercise (three “leader falls”), as the material had stretched and had holes in it. (Source: Ruth Mendenhall, Mugelnoos #522)