Assessment of radon concentration in a residential building – a case study

It is known that the highest contribution to the yearly radiation dose for population derives from natural radioactivity. About 50% of that is estimated to be caused by exposure to radon (Rn) and its products. Human exposure to indoor Rn is currently considered as a relevant research topic, because of the associated epidemiological aspects. This paper assessed Rn concentrations in the basement of a building in Kosice city, Slovakia. The continuously monitoring of indoor radon levels was performed over a period of 16 days, during a reconstruction of the basement. The measured concentrations ranged in a wide interval from 5 to 113 Bq/m3 with the average value of 24.3 Bq/m3. The WHO limit value of 100 Bq/m3 was exceeded only in a short period during two weekend days when the basement was closed and there was no activity and only limited air exchange. This could point to the potentially higher radon concentrations under normal operation of the building and thus to the increased radiological risk due to radon accumulation in the basement.