ON JUSTIFICATION OF CHANGES IN THE RADON CONTENT RATIONING IN INDOOR AIR

The deadline for the development of the final draft of the new radiation safety standards RSS-2019, harmonized with international recommendations, including the regulation of radon content in the indoor air of residential and public buildings is expected to be finished in 2019. We estimated the possibility and expediency for replacement of the hygienic standard established in RSS -99/2009 with the reference level recommended by the International Basic Safety Standards of IAEA GSR Part 3 on the basis of data analysis results on radon content levels in indoor air of residential and public buildings on the territory of subjects of the Russian Federation. An analysis of the array of measurements results for radon content with a volume of 680,301 measurements taken during the period from 2001 to 2017 in the subjects of the Russian Federation collected as part of Unified State System for Control of Individual Exposure Doses and stored in the Federal database of exposure doses of citizens of the Russian Federation due to the natural and man-made background radiation was carried out. Absolute and relative estimates of the number of radon EEVA values exceeding 200, 150 and 120 Bq/m3 were obtained, both for individual regions and for the country as a whole. The results show that the reduction of hygienic standard of radon EEVA will increase the share of the non-compliant regulatory instruments of residential and public buildings up to 150 Bq/m3 almost in 2 times, up to 120 Bq/m3 almost in 3 times on average in Russia. We formulated a number of proposals aimed at harmonizing the Russian standards of radon content in indoor air with the IAEA recommendations taking into account the economic feasibility and while maintaining the possibility of monitoring compliance with the requirements of radiation population safety.