EMPLOYEE, ALONG WITH TWO OTHERS, WERE CHANGING BUCKET TEETH AND SEGMENT ON EQUIPMENT. THE TEETH AND SEGMENTS FIT OVER ADAPTERS SECURED WITH PINS THAT ARE DRIVEN THROUGH ALIGNMENT HOLES IN THE WEAR PART AND THE ADAPTOR. ONE OF THE SECTIONS WOULD NOT LINE UP WITH THE PINHOLE SO THE EMPLOYEE TAPPED ON IT WITH A HAMMER. A METAL SPLINTER FROM THE SEGMENT FLEW UP AND HIT THE EMPLOYEE IN