A new air radon monitor is proposed based on the combination of an aluminum disk and an electric multilevel clearance system
(EMCS). The positively charged, small aluminum disk has a high collection ability to radon with a collection efficiency of
about 60%. The old radon progenies were eliminated by the EMCS in the air entrance of the monitor with an efficiency of about
99%. The monitor was calibrated in the national standard radon chamber in Hengyang, China. Compared to the radon double-filter
equipment, the results, gained by both apparatus, coincide with each other.