Abstract: Employee #1 was directing placement of a 16,000 lb bulldozer on the sixth floor of a building that was being prepared for explosive demolition. He was standing on planking over a chimney shaft. After the bulldozer had been resting on the floor for approximately 30 to 40 seconds, the brickwork in the chimney collapsed and landed on Employee #1. The brickwork broke through the planking, sending Employee #1 90 ft into the basement, where the falling rubble from the chimney buried him. Employee #1 died of massive injuries to his head, torso, and extremities. (His arm was found on the third floor.) The causal factors are: failure to inspect and secure areas prior to employee exposure (1926.859 (g)), and equipment used on floors unable to support it (1926.856 (a)).