Piped premixed 50 percent oxygen mixture (Entonox).
D000769:Anesthesia, Inhalation / Q000295:instrumentation*; D003080:Cold Temperature; D004865:Equipment and Supplies, Hospital; D006801:Humans; D009609:Nitrous Oxide / Q000008:administration & dosage*; D010100:Oxygen / Q000008:administration & dosage*; D055585:Physical Phenomena; D010825:Physics
D009609:Nitrous Oxide; D010100:Oxygen