Three employees were in a large interior area underneath a concrete silo. They were moving a screw conveyor housing out of the way in an area where they were planning to install a new screw conveyor flight. As they pushed the screw conveyor housing across the concrete floor, the front vertical angle iron support broke at the welded connection to the housing. As the housing fell approximately 21 inches to the ground, the injured employee's right foot was caught underneath and fractured. The injury required surgery and hospitalization.