Pushing nano-aerosol measurements to a new decade – Technical note on Airmodus Particle Size Magnifier 2.0

Abstract

Abstract. Accurate measurement of the size distribution of sub-10 nm aerosol particles is still a challenge. Here we introduce a novel version of the Airmodus particle size magnifier (PSM), which is a condensation particle counter-based instrument with a sizing range of 1–12 nm. The extended size range compared to the earlier PSM version enables direct detection of forming clusters and particles as well as studying their growth processes without the challenges related to particle charging. It also gives an overlap between the activation size distribution measurements with the PSM and mobility size distribution measurements with conventional mobility particle sizers. We compared the performance of PSM 2.0 to a mobility particle size spectrometer, the original A10 particle size magnifier and a Neutral Cluster and Air Ion Spectrometer (NAIS) during field measurements. Also, calibration results were compered against the A10 instrument. The results show that PSM 2.0 is able to activate sub-2 nm clusters and the concentration and size distribution between 2–12 nm compare well especially with the NAIS.