Abstract: At approximately 9:00 a.m. on May 27, 2007, Employee #1, a maintenance employee, was clearing a jammed part from a Clearing part revolution mechanical power press (Model Number F-1799-48; Serial Number 40.4606P). The press uses two pneumatic cylinders located on opposite sides of the press to knock the stamped part from the die. The main pneumatic line valve was closed and not locked out. Air in the air tank was bled off. The air tank supplies air to a Ross switch valve, operated by an electric solenoid that diverts air pressure to either the top or bottom of the pneumatic cylinders during the operating cycle. The air lines connecting the cylinders from the switch valve were not bled off and residual air pressure remained in the bottom air lines. Employee #1 removed the two blocks and a jack that he had used to push down on the cylinders. When the blocks and jack were removed, the residual air pressure pushed the cylinders upward to their original position. The tip of Employee #1's left pinky finger was amputated, when it was caught between the knockout bar and the bottom of an air cylinder. No witnesses were present when the injury occurred. No weather conditions or work environment conditions contributed to the injury.