Abstract: Employee #1 was attempting to repair a faulty gate valve. In order to do this he was to drain and depressurize a 4 in. zeolite water softener line that was blocked by a closed valve on both sides of the gate valve. When he opened bleeder valves on both sides of the valve and the pressure gauges on both sides showed zero pressure, Employee #1 attempted to remove the gate valve. Apparently, a vacuum in a section of the line contained hot water and steam. When Employee #1 removed the last bolt on one side of the valve, the line broke free from the valve and released hot water and steam spray, burning Employee #1.