Measurement of 222Rn at the Bqm-3 level with the AlphaRad chip

Abstract We describe a fully standalone compact electronic monitor for atmospheric 222 Rn, based on a new CMOS system-on-chip. The electronic board consists of three AlphaRad CMOS chips running in parallel, and it includes a numeric block for data treatment based on a Xilinx programmable gate array. In addition to classical tests (passive detection in a calibrated radon chamber), we present the first results with active collection of radon progeny present as aerosols.