A Simple and reliable monitoring system for H and C in radioactive airborne effluent

Koarashi, Jun   ; Mikami, Satoshi   ; Akiyama, Kiyomitsu; Kobayashi, Hirohide ; Takeishi, Minoru 

A simple and reliable sampling system for H and C in airborne release from nuclear facilities was designed. The sampling system can collect H and C simultaneously with a condensation technique using a commercially available cold trap equipment and a CO absorption technique using an organic alkali solution monoethanolamine, respectively. In situ performance tests for the effluent from a reprocessing plant showed that the system has the high and stable efficiencies for collecting H and C for a one-week batch sampling at a sampling flow rate of 0.4 l min. These collection techniques also provided a simple procedure of following sample preparations for activity measurement by liquid scintillation counting. The detectable concentrations of the proposed monitoring method were 3.0Bq/m for H and 1.6Bq/m for C, respectively. The sensitivity would be acceptable level for routine monitoring of airborne release at nuclear facilities.