Abstract: Employee #1 was using an autoclave pressure vessel to treat railroad ties with creosote. Upon completion, the creosote was pumped to a storage area. A coworker was opening the pressure vessel to remove the treated ties when the internal pressure, which had not been fully released, blew open the door. Employee #1 had been standing in front of the door and was struck by it, suffering a fractured skull. He was killed. The coworker, a fire tender whose job it was to feed the boiler and act as material handler to move ties in and out of the vessel, sustained minor injuries from being knocked to ground by the air release.