Abstract: At approximately 10:45 a.m. on Monday, June 21, 1993, Employee #1, a 38-year-old cement finisher, and a coworker were working alone on the second floor of a newly constructed addition to a manufacturing building. The concrete pour for half of the second floor, which measured 84 ft by 119 ft, had almost been completed and the two men were completing the finish on the fresh concrete. The remainder of the concrete subcontractor's crew of 13 men had descended to the first floor. Employee #1 was working with a bull float and apparently was backing up to an unguarded floor opening measuring 2 ft 8 in. by 18 ft 1 11/16 in. when he either tripped on the projecting edge and fell, or stepped, into the opening. He fell 16 ft 8 in. to a concrete floor. Employee #1 sustained head injuries and remained in a coma at the hospital until his death on Friday, July 2, 1993, at approximately 3:30 a.m. His coworker did not see what happened and there was no other eyewitness to the event.