Indoor radon measurements in Calabria (Southern Italy)

Radon gas from the ground is the main source of indoor concentrations in buildings, regardless of construction characteristics. According to Council Directive 2013/59/EURATOM, EU Member States must establish national reference levels for indoor radon concentrations in workplaces and draw up a National Radon Plan. In Calabria (Southern Italy), maps of indoor measurements at regional scale are not available. A set of 1434 average annual measurements, taken between 2010 and 2021, has been analysed. For a limited sector, a geostatistical approach allowed to map the expected concentrations at ground floor, the spatial uncertainty of estimates, and the probability of exceedance of the 300 Bq m(-3) Italian threshold for workplaces. Highest values characterize the eastern border of the Sila massif. Obtained maps might be used to optimize locations of additional dosimeters, based on geological constraints. Such studies may support urban planning policies and provide recommendations on building techniques.