Fatality Assessment and Control Evaluation (FACE) Report for New York: Tower Technician Killed When Guyed Tower Collapsed, FACE-09-NY-095.

摘要

In December 2009, a 46 year-old tower technician fell 43 feet to his death when a guyed communication tower collapsed. The 380-foot tall tower was supported by 21 guy wires at seven elevations, three at each height. The lowest three guy wires were at 43 feet. The victim and his coworkers were replacing the guy wires at the time of the incident. The workers first released the lowest three guy wires from the ground anchors. The next set of wires was at 93 feet. The tower immediately bent in response to the removal of the tension in the lowest guy wires. Tension gauge readings indicated that the remaining guy wires were either over-tensioned or tensioned unevenly. The workers adjusted the wires so that the tower was not bent. The victim, who was wearing a safety harness, started climbing the tower to remove the wires at the 43 feet. As he was climbing, the workers on the ground observed the tower to be moving "like a wet noodle." The victim dropped the three wires and quickly climbed down. He then climbed to 43 feet to install the new guy wires. He successfully attached two wires before switching to the other side of the tower to attach the third wire. Meanwhile, two workers on the ground picked up one of the wires that was just attached and pulled it hand tight. They took enough slack out of the wire so that it was elevated and not touching the ground. At this moment, the tower start to collapse. The tower reportedly buckled or bent at 43 feet where the victim was. The lower section of the tower (from 43 feet down) fell northwest, while the section above 43 feet fell to southeast (180 degrees from the direction where the lower section fell). The whole tower collapsed. The victim, whose harness was still hooked to the tower, suffered fatal crushing and fall injuries. One worker called 911 and the rest ran to attend the victim. The emergency response staff arrived within minutes. The victim was pronounced dead at the scene.