Abstract: Employee #1 was installing pipe connections to a main water sprinkler line at approximately 34 ft above the ground level. Employee #1 was working in a bucket of a JLG articulating aerial boom lift and was about one foot below the ceiling joist. Employee #1 was trained in the operation of the lift and was wearing appropriate fall protection. Two other employees were working in another boom lift about 50 ft away, when they noticed through the joists that Employee #1 was hunched over the controls. They thought that Employee #1 was asleep. The coworkers lowered their boom, and drove to Employee #1 to wake him. As they approached, they noticed that Employee #1 was wedged between the bucket controls and the ceiling joist and had turned blue. There was vomit on the floor under the bucket. One coworker went for help while the other lowered Employee #1's boom using the ground controls. Employee #1 was pronounced dead at the hospital. The cause of death was determined to be compression asphyxiation.