Gas measurement device

A gas measurement device comprising:

• an irradiation part, irradiating a target gas with irradiation light comprising a wavelength component in at least a portion of a wavelength range of 2.5 μm or more and 3.5 μm or less;
• a reflection part, reflecting the irradiation light and forming a detection space for the target gas;
• a reception part, generating a detection signal corresponding to an intensity at which the irradiation light is absorbed by the target gas;
• a calculation part, generating concentration information of the target gas based on the detection signal;
• and
• a heating part, heating the reflection part, wherein
• the reflection part comprises a metal portion containing aluminum and a protective film containing silicon;
• the calculation part is configured to calibrate conversion information for converting the detection signal into the concentration information;
• the calibration comprises data acquisition for the calibration;
• and
• the calculation part acquires the detection signal and a heating state of the heating part as input information, and performs data acquisition for the calibration according to the heating state.