Abstract: Employee #1, a steel erector, was working on the third phase of construction, which consisted of a large concrete foundation with upright concrete columns to support the steel I-beams along the east edge, the center, and the west side of the existing building. The steel I-beams that had been installed created eight bays. Bar joists of approximately 40 ft spans had been spread out between the beams. Each end of the bar joists had been welded, with the exception of those along the steel beam on the west side. A coworker began placing bundles of steel roof decking on top of the bar joists along the west I-beam, staggering them to prevent overlapping. A fourth bundle of roof decking had been placed farther out on the bar joists. Employee #1 and the coworker were attempting to receive another bundle of steel roof decking across the bar joists over the fourth bay on the west side. There had been no cross-bracing installed between the bar joists to prevent side movement, and the ends of the bar joists had not been welded on the west side. As a result, the bar joists moved and fell onto the concrete slab foundation. This caused Employee #1 to fall from the roof deck. He was killed.