Part of the continuous nationwide monitoring of radionuclides in Finland. STUK is responsible for monitoring of radioactivities in atmosphere. STUK operates a network of eight aerosol samplers from which three are located in Finnish, Lapland at Rovaniemi, Sodankylä and Ivalo. The sampling is done either weekly or bi-weekly. Gammaspectroscopic measurements are done in the laboratory in Rovaniemi. The lowest activities are detected at microBq/m3 level.