Particulate matter present in air is divided into different categories
depending on the size of the particles (aerodynamic diameter).
Coarse particles are the relatively large airborne particles
mainly produced by the mechanical break-up of even larger solid particles.
Examples of coarse particles include dust, pollen, spores, fly ash, and plant
and insect parts.
Coarse particles have an aerodynamic diameter ranging from 2.5 to 10µm
(PM10-2.5), which distinguishes them from the smaller airborne particulate
matter referred to as fine (PM2.5) and ultrafine
particles (PM0.1).