Note
Radiation Exposure Problems of Tourist Cave Workers Originating from Radon in Relation to the New IAEA BSS and ICRP Recommendations
2015 Volume 4 Issue 2 Pages 53-57
Details
2015 Volume 4 Issue 2 Pages 53-57
The regulation of radiation exposure originating from radon has become strict during the past years; in 2014 the reference level was given to be 300 Bq/m3 in case of dwellings and other buildings with high occupancy factor by International Basic Safety Standards (IAEA BSS) – released by IAEA – or the maximum allowable value in non-radiation conditions (radiation workers)1). We had previously been surveying the changes of radon concentration in the tourist caveʼs air for 8 years, and had measured the radiation exposure of those working there for 11 years. The 8-year average of radon concentration was 7430 Bq/m3. Before the renovation works at the end of 2011 (removing previous coal slag filling) it was 8630 Bq/m3, while during the years 2012-2014 it was 5430 Bq/m3, however, it still considerably exceeds the current reference level of 1000 Bq/m3 (and that planned for the future as 300 Bq/m3). The workersʼ radiation exposure has been surveyed individually using track detectors during the past 11 years. The average number of workers was 12 per year and the average radiation exposure was 10.6 mSv/year which resulted in a committed effective dose of 18.55 mSv/year calculated using the new recommendation. During the 11 years the annual effective dose exceeded 20 mSv/year in 6 cases. Applying the new dose conversion factor the actual radiation exposure exceeded the 20 mSv/year value in 44 cases where the average radiation exposure was 28.9 (20.4-53.0) mSv/year.
