In the paper some measurement results of number and size for aerosols particles suspended in air achieved using infrared particle sizer IPS-P (Kamika Instruments) with isokinetic air sampling method were presented. In IPS-P analyzer, with measuring range from 0,4 to 300 μm, is applied optical/electronic measurement method which is determined by dimensions of measurement space by aerosols particles motions in a parallel radiation beam. The research was conducted on the roof of four-storey building in Krakow for various meteorological conditions. Results achieved for measured parameters were analysed in terms of selected meteorological factors influence.

English title: Number and size measurements of aerosol particles in urban air using the optical/electronic method.