WORKING ON HOSING DECK. HIS NOZZLE WAS LEAKING SO HE WENT TO SHUT OFF WATER AND OBTAIN A NEW NOZZLE. HE WAS RETURNING TO HIS WORK SIGHT WHEN HE TURNED HIS HEAD AWAY TO AVOID BLOWING AIR AND WAS OBSERVING HIS NEW NOZZLE. HE HIT HIS HEAD ON A LOW CLEARANCE BEAM CUTTING HIS FOREHEAD.