Abstract: At 6:28 a.m. on May 20, 2021, Employee #1, a 34-year-old male maintenance technician III employed by W.W. Grainger, Inc., was performing preventive maintenance on an outbound belt-on-roller conveyor (No. 120260, Model No. 9410) inside the employer's distribution center in Minooka, Illinois. The employee removed a guard to inspect the running conveyor for noise. While standing less than a foot from the belt and pulley wheels, a rag in his right hand became caught in the pinch point between the running belt and a rotating pulley wheel. The rag pulled his right thumb into the pinch point, causing a partial fingertip amputation and lacerations to his right index, middle, and ring fingers. The employee immediately deenergized the conveyor and sought help. Emergency responders transported him to the hospital, where he received treatment and was released the same day. The incident occurred on a flat, illuminated floor in the basement's Dematic Multi-Shuttle area. No eyewitnesses or surveillance footage were available, and the accident scene was not preserved. The investigation was based on employee interviews and post-accident photographs.