Abstract: On February 22, 2002, Employee #1 was performing preventive maintenance on a Cannonaire Air Handler (Unit Model CF-24000-employer's Air Handler Number 4) on the roof of Building 18N and replacing a V-belt on the pulley system. Employee #1 deenergized and locked out the air handler and loosened the motor in order to remove and replace the V-belts. While Employee #1 was placing the V-belt over the pulley, the wind blew into the air handler, moving the fan and associated pulley shaft. The fan was a Twin City fan and blower system with Serial Number 011079. The movement of the pulley and the V-belt amputated the tip of his middle finger on his right hand. The accident occurred because the fan, shaft, and pulley were not blocked to prevent inadvertent movement, while Employee #1 performed the servicing operation. His employer is in the biotechnology industry with emphasis on research and development of human therapeutic treatment for the areas of inflammation and bone diseases, nephrology, neurology, and oncology.