A tritium-in-air monitor with compensation and additional recording of α-β-and γ- backgrounds

Development is described of a computer controlled tritium-in-air monitor using flow-through air proportional counters as the detector. Combining automatic compensation for β- and γ-backgrounds with α-background discrimination, the monitor can detect tritium activity separately from coexisting other radioactive gases. The computer of the monitor calculates and prints out not only tritium concentration in air but also dose equivalent rate by external γ-rays and/or activity concentrations of other radioactive gases than tritium in real-time. Since the monitor has a wide range of 0.005--5000 Bg/cm3 (6 decades) and a short response time of several min,it can be used effectively to monitor tritium in air in fission and fusion reactor environments