RADON SAFETY OF MODERN MULTI-STOREY BUILDINGS WITH DIFFERENT ENERGY EFFICIENCY CLASSES

According to results of the survey in Ekaterinburg, Russia, indoor radon concentrations above the city average level have been found in each of the studied buildings with high energy efficiency class. Measures to increase energy efficiency were confirmed to decrease the air exchange rate and accumulation of high radon concentrations indoors. Despite of recommendations to use mechanical ventilation with heat recovery as the main scenario for reducing elevated radon concentrations in energy-efficient buildings, the use of such systems did not show an obvious advantage. In real situation, mechanical ventilation system is not used properly both in the automatic and manual mode, which does not give an obvious advantage over the natural ventilation in the climate of the Middle Urals in Ekaterinburg