Overview of atmospheric radionuclide monitoring techniques for CTBT International Monitoring System

To verify compliance with CTBT, a cost effective International Monitoring System, which consists of monitoring stations, certified laboratories and International Data Centre, is now under establishment. Takasaki- and Okinawa-stations are those of 80 radionuclides monitoring stations, and radioactive particulates in the atmosphere will be monitored with a full-automatic monitoring system in the stations. In Takasaki-station, radioactive noble-gas (Xe) will be also monitored. Monitoring requirements for CTBT verification are severer than those for nuclear power plants. The available automatic systems for particulates monitoring satisfy with them. On the other hand, the system for noble-gas is still complex for daily work, and improvement of the system is needed. JAERI-Tokai is designated as a certified laboratory for detail analyses of the samples taken at stations, preparations for calibration sources and splitting the filter. An overview of the monitoring system and analytical techniques of radioactivities which will be used at Takasaki-station and JAERI-Tokai is presented. (author)