EE WAS MOVING A 450# DRUM OF OIL ACROSS SHOP FLOOR WHEN HE CAME TO A NARROW OPEING BETWEEN THE 4160 ROOM, DRUM CART ROLLED OVER A SEAM ON THE FLOOR. DRUM CART HIT THE SEAM IN THE FLOOR & JARRE D THE CATCH LOOSE FROM THE DRUM, ALLOWING DRUM TO MOVE UP & FORWARD.