THE INJURED WORKER WAS WALKING ON AN ELEVATED CATWALK THAT RUNS ALONG AN AIRSLIDE. THE CATWALK IS ACCESSED BY A TWO-STEP LADDER. AS HE WALKED ALONG THE CATWALK HE DUCKED UNDER AN OVERHEAD PIPE BUT FORGOT TO NOTICE THE STEP DOWN. HE FELL ONTOTHE CATWALK LANDING ON HIS KNEE, CAUSING A LACERATION.