Abstract: At 12:15 p.m. on March 6, 2020, an employee was working at a machine shop. She was a machine operator. The shop had six Mori Seiki CNC lathes. On three of these lathes, the interlocks had been intentionally disabled, or the interlocks had broken and had not been repaired. Those three were Mori Seiki model number SL-250B 500 CNC lathe, serial number 1393, shop lathe number 1; Mori Seiki model number CL-25A CNC lathe, serial number 834, shop lathe number 2; and Mori Seiki model number CL-253A CNC lathe, serial number CL253AGB301, shop lathe number 3. To polish parts, employees were required to use the spindle on lathe number 3, the lathe in the incident. Employees polished parts with sandpaper or a scouring pad. For this operation, the door had to be open. The interlock key had been permanently secured in the lock to "make the machine think" the door was closed. In this incident, the employee was polishing a part on the lathe spindle. The lathe was turning at 175 rpm. The employee's shirt sleeve or wristwatch got caught on a protruding bolt on the spindle. The employee was pulled in. She suffered a broken wrist, a broken jaw, and deep cuts on her neck. She was hospitalized for two or more days. There was a protruding bolt on the spindle because some three to six months earlier, the existing bolt had been stripped. The team leader had replaced it with a larger bolt until a replacement arrived. A bolt had been ordered, but the wrong size was delivered. The team leader said that the employee in the incident mostly worked on lathe number 3. Its interlock had been overridden for more than a year. If one hit the interlock release button, the door could be open, and the machine would run, albeit slowly. The shop manager said that there was no daily check to make sure that the interlocks were working. There was no preventive maintenance, and the machines were worked on only when they broke down. The violation worksheet detailed issues with the other two defective lathes.