摘要 |
A nitrogen oxide concentration measurement device comprises a zero scrubber disposed within a gas flow path, and a controller. The zero scrubber performs subjects exhaled air flowing through the gas flow path from a mouthpiece toward a chamber to a NO removal treatment in a first period, out of a first period and a second period. The controller acquires the concentration of NO contained in the exhaled air on the basis of the differential voltage value outputted in the second period, which uses as a reference the differential voltage value outputted in the first period. |