Abstract: EMPLOYEES #1 AND #2, ALONG WITH OTHER WORKERS, WERE EMPLOYED AS ELECTRICIANS ON A CONSTRUCTION PROJECT IN A STEEL MILL. AT THE TIME OF THE ACCIDENT, THE EMPLOYEES WERE INSTALLING ELECTRICAL EQUIPMENT IN A PIT LOCATED BENEATH THE COOLING BED PORTION OF THE ROLLING MILL. WITHOUT WARNING, A HORIZONTAL SHAFT, WITH ATTACHED COUNTERWEIGHTS, RUNNING THE LENGTH OF THE PIT, ROTATED 90 DEGREES TO ITS NORMAL POSITION. THE SHAFT BRIEFLY PINNED ONE EMPLOYEE BETWEEN A COUNTERWEIGHT AND THE WALL, AND STRUCK THE OTHER. EMPLOYEE #1 SUFFERED A COMPRESSION FRACTURE OF THE BACK. EMPLOYEE #2 SUFFERED A BRUISED LEG. THE INVESTIGATION REVEALED THAT THE AIR PRESSURE SYSTEM FOR THE ENTIRE MILL HAD BEEN BLED, FROM ANOTHER PART OF THE PLANT, AS PART OF A RELATED PROJECT. THIS ALLOWED THE AIR BRAKE WHICH HAD HELD THE COUNTERWEIGHTS IN A VERTICAL POSITION TO RELEASE. THE COUNTERWEIGHTS HAD BEEN INADEQUATELY SECURED AGAINST FALLING, AND THE WORK SITE HAD NOT BEEN INSPECTED FOR HAZARDOUS CONDITIONS.