Annual dose from radon in Mongolia

Today, the research of radon is one of the most important themes in nuclear physics and environmental science. Research in indoor air radon and outdoor air radon are very significant for hygiene. Outdoor air radon changes with geographical region, season, month and hours of day. And indoor air radon pertains from outdoor air radon, buildings material and ventilation. Experimental data of determination Rn222 by Scintillation method (SAC-4) in outdoor air, in premises of a microtron MT-22, other working rooms and dwellings (concrete, brick, wooden and Mongolian ger) are considered. With the purpose of research of radiation safety in indoor and outdoor of the microtron, we have developed a technique of determination radon and its short-lived decay product Po218 by the scintillation counter SAC-4. Concrete, brick, wooden, mongolian ger 4 buildings radon concentration in winter (November and December) of 6 years, measurements 400 points average to cause to out average and annual dose rate from radon are measured. Radon concentration has in outdoor air (winter) 18.7 (2.3/38.8) Bq/m3. Indoor air (concrete, brick, wooden, Mongolian ger) radon concentration has 26.0 (8.2/42.6) Bq/m3. Received dose rate annual to human of radon 0.8 (0.33/1.26) mSv/year. This concentration is less than maximum effective dose (2.5mSv/year) of human year. Mongolian National Standard 'Method of determination of radon concentration in air' (MNS5246:2003) is processed and certified. The work is carried out at the Nuclear Research Centre of the National University of Mongolia. (author)