Abstract: On May 23, 2011, Employee #1 and a coworker, both maintenance employees, were cleaning sand out of a belt conveyor because it went off track due to excess flow of sand from a mixer. One of the employees removed part of the tail pulley guard to adjust the bearings. In addition, they tried to remove the sand with shovels but the task was too overwhelming. The maintenance supervisor was consulted. He sent three additional employees to assist with the situation. Employees were positioned across a 40 ft wide mezzanine deck with one of them located at the control panel. The maintenance lead signaled the control operator to turn on or off the belt conveyor. When the conveyor was off, the employees would go in and under the conveyor belt to remove the sand using their arms, hands, shovels, and a vacuum cleaner. The maintenance lead would then signal to turn on the belt conveyor. This went on for approximately three to four times. While the belt conveyor was supposed to be turned off, Employee #1 was using his left hand and arm to clean out the excess sand near the unguarded tail pulley. The control panel operator turned on the belt conveyor that caught and amputated his left arm in the tail pulley. He was taken to a medical center, where he underwent surgical procedures and was then hospitalized for postoperative care.