Design of dual channel artificial radioactive aerosol monitoring system

Abstract Background: The environments for monitoring artificial radioactive aerosol are often complex, as sometimes it could even be in underground caverns, tunnels or underground nuclear facilities, of which the concentration of both radon and its radioactive products would be up to 10³-10⁴ Bq·m^-3. However, under high radon condition, the tailing phenomenon of radon and thorium peaks could interfere with radioactive counts and the artificial aerosol counts, thus affecting the detection limit of radioactive aerosol. Purpose:This study aims to design a special normal-pressured artificial aerosol monitoring equipment, which can operate well under the high radon environment. Methods: Dual-channel synchro measurement was employed to combine high accuracy of the vacuum channel and the fast response of the normal pressure channel. Results: Implemented aerosol monitoring system can respond rapidly to plutonium and uranium aerosol in atmospheric environment, and in the case of artificial radionuclide leakage, the fastest measurement results can be obtained in 30 min. In general, the theoretical detection limit can reach 10^-4-10^-3 Bq·m^-3, and the verifiable detection limit of uranium and plutonium are 0.1 Bq·m^-3 and 0.02 Bq·m^-3, respectively. Conclusion: This design can be applied to a variety of high radon environments which require unmanned monitoring for artificial nuclear. (authors)