On the identification of radon areas as defined in art. 103 of Council Directive 2013/59/EURATOM

Radon maps are one of the key tools for implementing a graded approach to reduce exposure due to radon. The Council Directive 2013/59/Euratom indicated how to identify the geographical areas of the country most exposed to indoor radon. Using annual average radon concentrations in 5000 dwellings in the Lazio region, located in central Italy, the expected number of dwellings with annual average radon concentrations above the reference level of 300 Bq per m3 within the 6 km grid squares was estimated. For the purpose of application, radon areas were identified by arbitrarily selecting grid squares with at least 10 expected dwellings per square kilometer above 300 Bq per m3. Since comprehensive measurements surveys must be conducted within the radon areas to identify all dwellings exceeding the reference level for the purpose of reducing radon concentration, quantitative economic considerations are reported.