Abstract: Measuring device for tritium in process exhaust using ionization chamber (effective volume 11.0 mL) was developed after material selection, structure design and parameter optimization. The calibration curve was plotted with a good linearity in the range of 0.013 4%—0.168% (v). The results showed that the detection lower limit of the device was 1.35×10^-4 %(v); the coefficient of variation was no more than 1.50%; and the response time was less than 10 s. The process measurement requirements were fairly met.

Key words: ionization chamber, tritium, background current, memory effect, calibration curve