Abstract: Employee #1 had been placing bolts and nuts in connection plates at the end of support beams on the second floor of the PC IEM Brine Mud Filter House, approximately 28 ft above the cement floor. Employee #1 was wearing a safety belt with a lanyard and had been tied off while bolting up; however, when he got ready to move to another location, he unsnapped the hook on the lanyard, which left him unprotected. The leadman, who was located on the cement floor, observed Employee #1 unsnap the hook on his lanyard. He saw the lanyard in his hand after he moved his bucket of bolts and his wrench to his left onto the beam that he was about to get on. Employee #1 turned around and got onto the small beam. The leadman turned, took a couple of steps, and turned to look at him again. When the leadman turned around, he observed the employee's right leg off the beam as the employee was falling. Employee #1 tried to catch himself on the beam with his arms and hung on for about a second. His arms popped up and he fell to the cement floor. He died.