Abstract: On September 3, 2010, Employee #1, a welder, was welding on the DDM log selector gate at the Rex Lumber sawmill. This gate was part of a conveyor system for logs. When the logs approached the gate on the conveyor system, the gate pneumatically closed if the log was large enough to trigger the gate. The large log was then conveyed to another part of the conveyor system behind the gate. If a log was not large enough to trigger the gate, the gate remained open, and the smaller log was dropped through the gate to be conveyed to another part of the conveyor system. Portions of this gate had become damaged and needed to be repaired. The DDM Wave Feeder and the Reception Belt conveyor system were deenergized and locked out. The DDM Edger Chipper Multifunction line operators control panel was being used to maintain the log selector gate in an open position. The Log Selection Gate control switch was placed in the "AUTO" position on the control booth console. This provided a compressed air energy source which was holding the Log Selector Gate OPEN while Employee #1 was welding on the trough of the machine where the logs drop down onto the reception belt. There were two safety chains attached to the side of the machine. These chains were used to hold the gate open in case the facility lost electrical power, which would cause the Log Selector Gate to lose compressed air and the gate would close. A coworker entered the DDM operators control booth to turn off some Log Accumulation Deck chain conveyors which were left running by the day shift. When the coworker turned the Log Accumulation deck chains control switch to the OFF position, the Log Selector Gate closed immediately, crushing Employee #1. The coworker was not aware the Log Accumulation Deck chains were interconnected to the Log Selector Gate machine. Employee #1 sustained blunt force injuries to the chest and abdomen, and died on the site.