Abstract: At noontime, on December 9, 1997, Employees #1 and #2 were installing drywall panels in a ceiling in a residence under construction. To access the high ceiling over a staircase, Employees #1 and #2 installed a 2-ft by 10-ft plank across two scaffolds uprights, 10 ft apart. According to the police report, the plank was about 12 ft to 16 ft above the floor. Employee #1 was using an electric drill to screw the drywall panel to the frame, while Employee #2 held the panel to be installed. While both of them were standing in the center of the single plank, the plank broke in two, dropping Employees #1 and #2 to the staircase and then to the floor. Employee #1 sustained a broken left ankle and complained about pain in his left knee. Employee #2 complained about extreme pain in his back and legs and sustained abrasions on both knees. Employee #2 also had a screw impaled in his right cheek. Employees #1 and #2 were taken to the Cedar Sinai Hospital for treatment.