EE AND OTHER WERE CLEANING UP SPILLAGE IN THE #6 COOLER PIT ALONG SIDE THE DISCHARGE SKIP ON 2/9/04. AT APPROX. 8:45AM, EE WAS SITTING ONT HE LOW ROLLER CHAIR MOVING THE 6"" SUCTION HOSE WITH H IS RIGHT FOOT/LEG, WHEN SUDDENLY HE FELT SHARP PAIN IN HIS RIGHT KNEE AND IMMEDIATE LOSS OF USE. HE GOT OUT OF THE PIT AREA AND WENT FOR MEDICAL ATTENTION FOR A KNEE SPRAIN, AND RESTRICTED DU