Abstract: On Thursday, May 21, 1992, at the Colfax Elementary School construction site in Colfax, CA, a general contractor requested help from a carpentry crew to erect a 50 ft steel beam and columns; neither the general contractor nor the carpenter were trained in steel erection. The steel beam was raised into position using two forklifts. Guys were set at one end, but the column footing bolts were not secured, and only one guy was attached at the other end. When the two guys were attached at the east end, the forklift sling was released by Employee #1, of Polar Construction, who was working from a scissor lift. When the single guy was attached at the west end, the fork released the tension on the chain sling (the other guy was not attached because the turnbuckle had broken two weeks earlier when the beam had been originally set by an erection crew). The chain sling unhooked when the tension was released. Because the beam was not guyed at one corner and the column footings were not tightened, the beam leaned over, unwrapping the chain sling. The weight and force of the beam pulled the turnbuckle apart on the northeast corner. The beam then fell over onto the scissor lift, knocking Employee #1 to the concrete floor. He landed on his back and head, sustaining severe head injuries. First aid was administered and he was then transported by helicopter to UC Medical Center in Sacramento for treatment of his head injuries.