2024 Yes Indoor Radon Measurements in Finnish Daycare Centers and Schools—Enforcement of the Radiation Act https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7215769/ Kojo, Katja Europe Exposure Radon Radon Surveillance School Daycare center Radon surveillance in Finnish daycare centers (633) and schools (1176) found mean levels around 80 Bq/m³; 8% of daycares and 14% of schools exceeded 300 Bq/m³. Systematic campaigns ensured measurements and reduced radon exposure risk. 2020