Light absorbance analysis apparatus and program record medium for recording programs of light absorbance analysis apparatus

A non-transitory program recording media, the media comprising:

• a recorded program used for a light absorbance analysis apparatus, the apparatus including a detector that detects an intensity of light that transmits a gas, a total pressure sensor that measures a total pressure of the gas, and a controller, including a processor and a memory storing a program, which when executed by the processor, performs operations, including:
• calculating an absorbance based on an output value of the detector and a previously set zero reference value,
• storing a partial pressure—absorbance relational data that shows a relationship between a partial pressure of an interference gas that exists in a measurement area of the detector and the calculated absorbance,
• calculating an interference gas partial pressure, in a known concentration state, wherein the interference gas whose concentration is known exists in the measurement area, based on the total pressure measured by the total pressure sensor and the known concentration,
• estimating an interference gas absorbance based on the interference gas partial pressure and the partial pressure—absorbance relational data, and
• conducting the zero calibration that updates the zero reference value based on the interference gas absorbance and the output value of the detector in the known concentration state,
• wherein the light absorbance analysis apparatus conducts the zero calibration on the detector even when the interference gas exists in the measurement area of the detector.