This application note describes a 6-minute Agilent 7890A GC-based refinery gas analysis (RGA) system. The system consists of 7890A GC, three detectors (TCD, ECD and FID), five valves, a 10-port valve and seven columns. The system can fully analyze nC6 and below hydrocarbons and permanent gases, including nitrogen, hydrogen, oxygen, carbon monoxide and carbon dioxide, within 6 minutes.