The present invention can provide a system and method for D LCO qualitycontrol testing andcan include an apparatus for testing a pulmonary diagnostic device capable ofperformingsingle breath carbon monoxide uptake measurement, comprising； a single gas-tight chamber,with a gas port configured to receive gas from or to expel gas to the exteriorof the chamberand a partition configured to change the volume of the single gas-tightchamber； the singlegas-tight chamber capable of expanding and contracting； a member disposedwithin the singlegas-tight chamber and configured to limit the movement of the partition, themember beingadjustable to set a predetermined maximum volume of the single gas-tightchamber and apredetermined volume of D LCO test gas that the single gas-tight chamber canreceive； and aninterface configured for the transfer of gas between the pulmonary diagnosticdevice and thesimulation device via the gas port.
