Abstract: On November 4, 2005, Employee #1, a dryer operator at a corn processing facility, was troubleshooting a centrifuge that partially removes moisture from cornstarch. Employee #1 noticed that the centrifuge's feeler knife was approximately 90 degrees from its normal position. He reached into the cam area with his left hand to see if the system was loose. As he had his hand on the cam, something caused the feeler knife to spin around, pinching his left thumb between the external cam and the limit switch. Although his thumb was amputated at the first joint, he was not hospitalized. The force also caused the cam to break the limit switch plunger at the roller end. The centrifuge was in operation at the time of the accident.