Abstract: At approximately 11:24 a.m. on April 5, 2006, Employee #1, a mechanic, and a coworker were removing a ripper shank assembly from a 1998 Caterpillar-D8R bulldozer (Serial Number 7XM2943) for repairs. They removed both the tilt cylinder pins at the top of the tool bar, which caused the tool bar and the ripper shanks to swing forward. The left ripper shank teeth swung toward the left track of the bulldozer, striking and pinching the left heel of Employee #1. He obtained a serious fracture to his left heel. The employees had not made arrangements to eliminate the injury hazard that would be caused by the sudden movement of the bulldozer or its parts. The bulldozer under repair was equipped with sharp and heavy moving parts. The moving parts were not securely and positively blocked in an inoperative position prior to removing the tilt cylinder pins. Emergency medical personnel were summoned. They arrived and transported him to a medical center. At the hospital, he underwent surgical procedures to repair the heel fractures. After undergoing the surgical procedures, he was hospitalized for postoperative treatment.