Abstract: Employee #1 placed a 10 foot fiberglass stepladder, in the closed position, against the side of the SDA tank. The ladder was placed on the checker (diamond) deck, which had been painted with epoxy paint. The checker deck, at an elevation of 79 feet 4 inches, is the floor of the penthouse, which is near the top of the SDA steel structure. The stepladder feet were about 3 feet from the vertical outside wall of the SDA; the ladder's contact point was about 6 feet above the floor against the edge of the outside wall. On the south and north side of the penthouse are two doorway openings. At these locations, there are no guardrails. Employee #1 placed the stepladder on the deck so that its feet were almost centered in the doorway. As the employee climbed the stepladder to the 4th step, its rubber padded feet slipped, causing the ladder and Employee #1 to slide out the door opening. Employee #1 fell and struck the stair tower's steel structure at the 50 foot elevation, then struck the structural steel at 20 feet. Employee #1 came to rest on the ground. He died from his injuries.