Abstract: At 2:10 p.m. on February 5, 2003, Employee #1, a welder at a machine shop in Azusa, CA, was tack welding two pieces of 11-ft-diameter metal pipes. One pipe was resting on a platform with wheels; an overhead crane suspended the other pipe during the welding. After Employee #1 unhooked the pipe from the crane while on a 20-foot-aluminum-extension ladder, it displaced while he was descending and he fell approximately 10 ft to the concrete floor. The ladder was tied to the wheeled platform, but a coworker who had been welding on the other side of the pipe moved the platform out to prepare to release the pipe from the crane. Employee #1 was hospitalized with fractures of his left wrist and lower arm.