Radon control in Estonia

Radon surveys started in Estonia in 1989. The Department Building Physics at the Estonian BuildingResearch Institute measured radon levels in dwellings, in building materials produced in the country,and in the soil. The indoor radon concentrations in more than 400 houses were measured under grabsamplingtechniques using Lucas cells. The highest measured radon level was 6700 Bqm-3. The resultsof these measurements made during 1989-91 showed that the main source of indoor radon is the soilunderneath buildings.