Abstract: On November 2, 2007, Employee #1 was working as a laborer for a construction company that was engaged in "tenant-improvement" work at a warehouse, such as removing spray booths, patching concrete, and removing spray booth duct work from the roof. The duct work had been detached from the roof by a coworker the day before, leaving six openings of various sizes in the roof. Two of the holes had been framed with 2-by-4s, and plywood had been permanently installed in these openings. Two of the four remaining openings were covered with plywood that was neither secured nor marked. Another of the openings was being framed by a coworker at the time of the accident. The last opening was covered with a piece of metal ducting that had a 74 in. square screen enclosure. On the morning of the accident, Employee #1 and a coworker were instructed to remove scrap metal ducting from the roof. They were picking up the various pieces of the ducting, tying a rope around them, and lowering them off the roof to the ground. When they got to the metal ducting that was covering the fourth hole, it was neither secured nor marked. As they prepared to pick it up, they were standing on opposite sides of the ducting and were facing one another. They had picked up the ducting when Employee #1 moved forward a few steps and walked into the 42 in. sq opening, falling 20 ft 9 in. to the concrete floor of the warehouse. He suffered blunt head trauma and multiple skull fractures that led to massive cerebral hemorrhaging. Employee #1 was unresponsive at the scene and was transported to Northridge Hospital, where he was pronounced dead. The employer was cited for an accident-related violation, serious, of T8CCR 1632(b)(3), floor, roof, and wall openings to be guarded.