No one was injured when chunks of concrete weighing up to 20 pounds fell from the ceiling in a roped-off area in a building at the Y-12 National Security Complex in March.
That area of Building 9204-2 in Y-12‘s production area had been roped off to restrict worker access. The controlled area has been in place since 2009, said B&W Y-12, the plant’s managing and operating contractor. Access to the area was controlled with marker tape and boundary markers.
When the ceiling fell in that part of the building, large chunks of concrete rebounded into a frequently used walkway and an adjacent welding station, the Defense Nuclear Facilities Safety Board reported in the week ending March 21. Workers had used the welding station earlier in the day, the DNFSB said.
B&W Y-12 said chunks of the concrete fell to the floor and struck a portable welding exhaust unit located inside the controlled area. Some small pieces of the concrete also scattered outside of the area. Personnel in a nearby area heard the noise, discovered the problem, and immediately notified the shift manager, per procedures, the contractor said. [Read more…]