Notes: The first nation wide survey of indoor radon in Iceland was conducted in 2012-2013. The annual mean radon concentration was measured on the ground floors or basements of 250 homes around the island. Volunteers were sought so the measurement locations were not randomly assigned. Additionally, measurements were made in 32 kindergartens and 19 public swimming pools. The results indicate that the radon concentration in Iceland is very low. The mean is 13 Bq/m3, and the median 9 Bq/m3. The distribution of the results is heavily biased towards the lower values with a number of the results at or below the minimum detectable activity and 95% of the results below 40 Bq/m3 and the highest value is 79 Bq/m3. No appreciable differences were found between the different regions of Iceland except that slightly higher values were found in the North of the country. Measurements in kindergartens and swimming pools gave even lower values.
  