Abstract: On July 11, 2003, a construction employee was placing sheets of plywood at the entrance opening to a concrete influent equalization tank to prevent dirt form dropping through the grating. He was working with his foreman when he fell 22 feet through a floor opening in the fiberglass grating. Prior to the accident, the employee picked up two, 4 feet by 8 feet by 0.5 inch-thick plywood sheets, which were stacked on top of each other. While attempting to push them toward the entrance of the equalization tank, he unexpectedly fell 22 feet through a floor opening. The employee suffered life-threatening injuries and died on July 22.