EE WAS USING A HAMMER TO REMOVE FROZEN BOLT FROM RADIATOR MOUNT. HE WAS USING A SMALL HAMMER THAT WAS BEING USED AS A PUNCH WITH 2 LB SHOP HAMMER. A SMALL PIECE OF THE HAMMER CHIPPED OFF AND S TRUCK HIM IN HIS LOWER ABDOMEN. THE SKIN WAS PENETRATED AND THE METAL CAME TO REST APPROX 1"" DEEP.