Abstract: Employee #1, age18, was an attendant for a 24 ft tall mobile vertical climbing wall attraction at an amusement park. The patrons were normally harnessed and could control-climb to the top of the wall, then repel downward without risk of free fall, because they were protected by pneumatic ballasts and a backup ballast control. At the time of the accident, one of the patrons ascending the wall detached a carabineer from his harness. The system caused the carabineer to rise to the top of the wall since it was no longer attached to the minimum weight (40 lb) required to hold it down. Seeing this, Employee #1 began to climb the wall freestyle to retrieve the carabineer. When he reached the top of the wall, he grabbed the carabineer at the end of the cable, but was unprepared for the resistance inherent in the controlled descent he was attempting. He lost his grip on the end of the cable and fell approximately 22 ft onto the concrete floor. Employee #1 sustained a shattered right wrist, a broken left elbow, and a fractured left eye orbit. He could have put on a climbing harness before climbing the wall, just as a patron would have been required to do.