INJURED GOT OFF HIS RIDE AT #113 BREAK TO CALIBRATE THE CO MONITORS IN THE BELT ENTRY. HE WAS CARRYING A CO CALIBRATION KIT. HE HAD TO BEND OVER FOR THE LOW TOP. WHILE WALKING HE SLIPPED AND F ELL ON WHAT HE THINKS WAS A PIECE OF TROLLEY GUARD. HE GOT BACK ON HIS RIDE AND WENT TO SLOPEBOTTOM. AS HE WAS WALKING HIS FOOT WAS BOTHERING HIM.