Abstract: At 12:40 p.m. on September 8, 2020, an employee was using his hands and a stick to reach into an opening of the single notching machine to clear debris, while it was still in running service. The injury occurred when the employee's arm was pulled into the cutting blades of the single notching machine, as he was trying to clear debris. The employee suffered an amputation of his right arm, just below the elbow. The employee was transported to Arrowhead Regional Medical Center, where he was hospitalized for five days. The followings are the factors that would have prevented the accident: (1) Apply lockout/tagout procedures to remove the single notching machine from running service and (2) train the employee on lockout/tagout procedures for the single notching machine.