CHANGING SCREEN ON EL JAY SCREEN BOX BOLT THAT HALF THEM IN PLACE WERE BEING REMOVED WITH AN IMPACT WRENCH AND A BAR WAS BEING USED TO PRY THE SCREEN TRAIL AWAY FROMT HE SIDE OF THE SCREEN TO TRY AND KEEP A BOLT FROM SPINNING IN THE RAIL AND THE BOLT WAS REMOVED TO THE BOX SLIPPED, CAUSED OTHER TO LOSE HIS BALANCE FALLING BACKWARDS ONTO THE SCREEN AND THE BAR FLEW OUT OF HIS HAND T