The contractor was fortunate that he was stopped in time to prevent an electrical shock or injury. Electrical personnel locked out and inspected the 480-volt cable. They repaired the damaged conduit and returned the cable to service. Investigators determined that the conduit to be removed had not been marked to eliminate confusion with other conduit in the area and prevent accidental removal of the wrong one. NFS has reported other events in the Weekly Summary concerning personnel cutting conduit that contained energized cables and wires.
Some examples follow.
When the blade penetrated the metal conduit and the cable, an electrical arc occurred. Investigators determined that a supervisor had directed the subcontractor to cut the wrong conduit. Although the electricians were trained and qualified, they cut the conduit in violation of their work permit and site safety procedures that require equipment to be locked out and tagged out. When the workers cut the conduit and wire they observed arcing and sparking. These events underscore the hazards involved when energized cables are accidentally cut.