Nano-size radon short-lived progeny aerosols in Slovenian kindergartens in wintertime

Indoor air concentrations of radon and radon short-lived decay products, equilibrium factors, unattached fractions of radon short-lived decay products (fun), relative humidity, and temperature have been measured in 29 rooms of 13 Slovenian kindergartens, with an emphasis on fun as a crucial parameter in dose assessment. Dose conversion factors, based on the measured fun values were compared to epidemiology-based value of 5 mSv WLM−1.