Abstract: On June 30, 2004, an employee was setting up a 5-ft-high scaffold on the first floor so that masons could fill in brick above the lintel for a sliding door. In a corner west of the door was a 60-in. by 42-in. hole in the concrete floor. The floor opening was covered by plywood. There was no indication that an opening existed under the plywood. During the process of erecting the scaffold, the employee fell through the floor opening from the first floor to the sub-basement. The employee fell 15 ft. 8 in. As a result of the fall, the employee fractured his neck. He became quadriplegic and was hospitalized.