Long-term Average Radon Levels Measured in a Few Days: Implications to Risk Communication and Mitigation Strategy

In the European Council directive (2013/59/EURATOM) the reference levels for radon are based on the annual average concentration (max. 300 Bq/m 3 ). Waiting a year or longer for detector exposure and analysis completion demotivates many stakeholders to give serious consideration to the radon problem and its consequent mitigation. We propose an approach for a speedy problem identification, yet that is still relying on a direct measurement of the annual average radon concentration. The CD/DVD method is used, where one or more compact disks (CDs) or digital versatile disks (DVDs) that were present for a duration of more than one year inside the house are analyzed. A radon problem in the house can then be identified quickly (in days) after the disks are collected and, if necessary, the mitigation can also be initiated shortly thereafter. The whole process is best managed by a radon expert. To perform prompt mitigation, the expert can collaborate with small licensed construction companies. Using this approach, shortly after a radon problem has been identified twenty buildings in Bulgaria (mostly kindergartens and schools) were successfully mitigated.