a logic circuit configured to obtain reference data, which indicate temporal variation of moisture concentrations, after injecting water-vapor with known concentrations into an analyzer;

a logic circuit configured to measure subject data indicating temporal variation of output-responses of a subject sensor element of the analyzer under test, the subject data are obtained under the same condition with the reference data was obtained;

a logic circuit configured to compare the subject data with the reference data, with same time-duration for obtaining the reference data, the time-duration is measured from a timing at which the water-vapor with the known concentrations is injected for calculating relationships between the output-responses of the subject sensor element and the known concentrations;

an injector configured to inject a constant volume of a calibration gas;

an inlet configured to receive a tip of the injector;

a flowmeter configured to control a flow rate of a background gas;

a moisture sensor configured to accept the subject sensor element, an output of the moisture sensor is connected to the processing unit;

a first pipe for introducing the background gas to the flowmeter;