Abstract: At 8:00 a.m., Employee #1 was monitoring the Mueller Martini 240 three knife book trimmer. Books measuring 6 in. by 9 in. came off a conveyor and dropped into the hopper before being fed toward the three knife trimming section. During book processing a 4 3/16 in. long and 1 1/4 in. wide opening was created in the metal hopper bed that allowed the hopper bed to go up flush to the next conveyor belt as it traveled back and forth. Because the opening was never thought to be a problem, it had never been guarded. When a book jammed in the hopper, a common occurrence, Employee #1 reached her right hand around the back of the hopper to free the jammed book. She placed her left hand on or near the hopper bed to brace herself, and unknowingly placed her left index finger over the opening in the metal plate hopper bed. Before she had time to clear the jammed book, the moving metal hopper bed had caught her finger in the opening and sheared off the fingertip just below the nail. Employee #1 was hospitalized but the fingertip could not be reattached.