Abstract
The main aim of this abstract was to describe the behavior of the intermodal fraction of the atmospheric aerosol. The particle size of the intermodal fraction (PM2.5-1) is located between fine (PM1) an coarse (PM10-2.5) particles.
These two fundamental and most studied particel sizes ovelap in the size range of this intermodal fraction and they have not only different size, behavior, residence time in the atmosphere and chemical composition but also different sources. The associations between these fractions were identified outdoors at urban (Ostrava - Radvanice) and suburban (Ostrava - Plesná) sites during winter season.