Fig. 1. Gas diagram during inspiration. AGS = anesthetic gas scavenger system; APL = adjustable pressure limitation valve; Exp. Valve = expiratory valve; Insp. Valve = inspiratory valve; MAN/AUTO = reversing valve between manual/mechanical mode; PAW = airway pressure; PEEP/PMAX = positive end-expiratory pressure/pressure limitation valve; SPONT/MAN = reversing valve between spontaneous/manual mode.