EE WAS STANDING ON TOP OF THE TUB OF A 1370 DRGLINE WAITING WHILE A HOIST WAS BEING LOWERED DOWN IN ORDER TO REMOVE STEEL THAT HAD BEEN CUT OFF THE TUB. AS THE HOIST WAS BEING LOWERED INTO THE COMPARTMENT WHERE EE WAS STANDING, THE CABLES CAME UNDONE FROM THE DRUM AND THE CRANE HOOK AND CABLES FELL ABOUT 4-6 FT AND HIT EE ON THE FOREARM.