EMPLOYEE WAS TAKING OFF NUTS TO CHANGE JAW PLATE AROUND JAW CRUSHER. THE EMPLOYEE WAS USING A 5-N-1 TOOL TO LOOSEN NUTS WITH. EMPLOYEE TAPPED THE PIN ON THE 5-N-1 TOOL WITH A HAMMER TO RELEASE IT AND WHEN HE DID THE HANDLE SPUN AROUND HITTING EMPLOYEE ON TOP OF RIGHT HAND.