Abstract: Employee #1, age 19, and a coworker had just added the last components of a fireproofing mixture into an electric cement mixer. The mixer had recently been moved to start fireproofing work, and its long extension cord could not be found. Instead, a short, 6-ft-long cord was plugged into the outlet box on a pump. The outlet box had a disconnect switch to control it so the switch on the mixer was put in the 'start' position. The mixer was turned off when both Employee #1 and the coworker looked inside to see if the fireproofing mixture was ready to be dumped into the pumps. Employee #1 told his coworker he was going to check the texture and firmness, and then turned his back as the coworker moved toward the disconnect switch to turn it on. Employee #1 was putting his arm into the mixer when it became caught in the rotating blades. The coworker saw Employee #1's arm in the mixer just as he closed the disconnect switch and immediately opened the switch, but Employee #1's arm had already been struck. He sustained injuries that required hospitalization. The mixer did not have a guarding grate over the opening to prevent Employee #1 from putting his hand or arm into the blades.