The sampling campaign was conducted during two periods in early spring and summer 2013 in Plzeň - Litice. The 3 and 8 size fractions of atmospheric aerosol were sampled by 3DRUM/8DRUM impactor with an integration time of 30, 60 and 120 minutes.
Also hourly averages of PM10 PM2.5 and PM1 concentrations by GRIMM and the 10 minutes averages of wind speed and direction together with precipitation were measured. The five DRUM samples were chosen for detailed SEM EDX analysis according to PM10, PM2.5-10 and PM1-10 concentrations and meteorological conditions.
The number of the critical actinolite fibres increased with PM10/PM1-10 and PM10/PM2.5-10 ratio increase, WS > 2 m.s-1 and precipitation < 1 mm. Based on the results the number of the critical actinolite fibres is WD independent thus the actinolite fibres sources are ubiquitous.