Abstract: Employee #1 and coworkers were assembling the boom of a crane. While the operator was climbing into the cab and the foreman was positioning himself to be the signalman, Employee #1 positioned himself beneath the boom butt, which was approximately 36 in. above the ground. The tip of the boom was approximately 12 in. above the ground. The Bucyrus Erie 60 ton crane was in the travel mode with a 20 ft boom tip attached by the wire rope. When Employee #1 knocked out the lower connecting pins from the boom assembly, prior to the boom being grounded, the boom section hinged on the remaining two top pins and the end of the butt section struck Employee #1. Employee #1 sustained injuries to his abdomen leading to hypovolemia, hypoxia, and cardiac arrest and died.