Abstract: Employee #1 was hooking up a chain sling to a steel storage tank that he would be welding. He was using a metal extension ladder to access the hookup points on the tank. A coworker, who had formed and assembled the pieces for the tank, told Employee #1 to wait until he walked around the tank to hold the ladder before climbing. Employee #1 did not wait; he climbed the ladder and started attaching the sling. Employee #1's movement on the ladder caused it to shift and slide on the tank against which it was resting. Employee #1, who was on the fifth rung, tried to jump free of the ladder but his foot went between two rungs. He pitched forward face-first, striking the ladder and then the concrete floor, and was killed.