EMPLOYEE WAS WORKING ON A DUST SCREW CONVEYOR. WHILE ATTACHING A CHAIN HOOK ON A STEEL BEAM OVERHEAD, THE WEIGHTED ARM OF AN OVERHEAD DOUBLE-DUMP VALVE ACTUATED & CAUGHT HIS WORK JACKET, PULL ING HIS ARM INTO A PINCH POINT BETWEEN THE VALVE'S WEIGHTED SHAFT & THE ADJACENT STEEL CHANNEL FRAMEWORK. HE WAS RETRACTING HIS ARM FROM SETTLING THE CHAIN HOOK WHEN THE VALVE ACTIVATED.
U.S. Mine Safety and Health Administration