Radon care

The dataset shows which areas in Norway are likely to be more exposed to radon than others. The data set is based on geology and indoor air measurements of radon. Internal air measurements are from NRPA’s national database, and geology is from NGU’s bedrock and loose mass databases. Berggrunnsdata is by scale 1:250,000 and loose mass data are of varying scales, from 1:50.000 to 1:1000.000. Indoor air measurements are used to identify areas of increased care for radon, a total of 34563 geo-referenced measuring points. They are also used to characterise geology in relation to the care of radon, and this knowledge is transferred to areas where there are no or few indoor air measurements. Where an area is classified as “high due diligence” it is estimated that at least 20 % of homes have radon concentrations above 200 Bq/m³, with 70 % statistical safety. Where an area is classified as “medium to low care”, it is estimated that up to 20 % of homes have radon concentrations above 200 Bq/m³, with 70 % statistical safety. Alum shale is associated with elevated radon concentrations. Areas where alum shale is found are classified as “particularly high care”. By transferring knowledge from areas with indoor air measurements to areas without indoor air measurements, it is assumed that radon properties of a geology type are the same throughout the country. In practice, some variation in radon properties in polygons of the same type of geology can be expected. In addition, variation in radon properties within a polygon can be expected.