Notes: National radon survey conducted by regulator – Gossannadzor of Ministry of Health – inside new buildings, Ministry of Architecture and Construction – on stage of site selection (radon in the soil). Some scientific investigations have been done in Belarus since 2004 up to now and the results of the measurement are: Measurements using integral method (exposure time 2-3 months) with SSNTD (LR-115 Type2). Number of measurements 5086 (75% dwellings, 20%public places and administrative buildings, 5% schools and kindergardens), Statistical distribution of radon-222 concentration: 0-100 Bq/m3 – 74.11% of observed buildings, 100-200 Bq/m3 – 19.81% of observed buildings, >200 Bq/m3 –  6.08% of observed buildings, >1000 Bq/m3 –  0.1% of observed buildings. Statistical distribution of equivalent equilibrium concentration: 0-100 Bq/m3 – 88% of observed buildings, 100-200 Bq/m3 – 9.9% of observed buildings, >200 Bq/m3 – 2.1% of observed buildings, >1000 Bq/m3 – 0.02% of observed buildings.  