Abstract: Employee #1, a member of a five-man metal decking crew, was working near the center of a very large flat roof on a structural steel building under construction. He was filling in the last of four 3 ft by 35 ft metal acoustical deck panels that had not been bolted up the previous day. There was a stack of panels sitting at the northern end of this 6 ft wide opening. One panel had already been pulled over to the southern end of the opening and was lying diagonally across the open end. As Employee #1 was walking around the south end of the panel to put it into position, he took his eyes off where he was walking and stepped onto the unsupported end of the panel. The end of the panel gave way. Employee #1 lost his balance and went through the 6 ft wide opening. He fell 43 ft, landing on his back in the sand.