THIS WAS A NEW PCC FINISH MILL STRUCTURE THE FALL PROTECTION LIFELINES HAD NOT BEEN INSTALLED EE AND HIS CO WORKER WERE 21' HIGH INSTALLING FLOOR GRATING 4'X20' HE WENT TO STEP OVER SMALLER FL OOR GRATING 4'X8' DURING A LIGHT DRIZZLING RAIN , IT SLIPPED AND HE FELL 21.