In the frame of the European metrological research project MetroERM, a compact portable aerosol sampling and measurement device was developed at Jožef Stefan Institute. The system incorporates a CeBr3 scintillation detector positioned centrally within a concertinaed filter assembly and an improved high flow rate air pump. It provides continuous on-line low level airborne radioactive particulate monitoring for field station use via 3G network communications. The calibration of the device was performed at National Physical Laboratory (NPL) with filters, spiked with a certified mixed nuclide solution. Additionally first tests were performed in an environment with an elevated radon concentration. •A compact portable aerosol sampling device was developed at Jožef Stefan Institute.•The system incorporates a CeBr3 scintillation detector positioned centrally within a filter assembly and high flow rate air pump.•The calibration of the device with filters, contaminated with CRM was performed at National Physical Laboratory.•First tests were performed in the environment with elevated radon concentrations.