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INDOOR RADON CONCENTRATIONS CAUSED BY CONSTRUCTION MATERIALS IN 23 WORKPLACES

Pirjo Korhonen 1,2 , Raimo Halonen 2 , Pentti Kalliokoski 2 and Helmi Kokotti 2
1 Uusimaa Regional Institute of Occupational Health,
Arinatie 3A, FIN-00250 HELSINKI, FINLAND 2 University of Kuopio, Department of Environmental Sciences
P.O.BOX 1627, FIN-70211 KUOPIO, FINLAND

The aim of this study was to compare the measured and the calculated concentrations of indoor
radon caused by building materials at 23 workplaces. The measured concentrations of radon were
clearly higher than the calculated radon concentrations from the building materials indicating that
the main source of indoor radon was the soil under and around the buildings. The highest means of
continuously (933 Bq m -3 ) and integrated (169 Bq m -3 ) measured and calculated (from 70 to 169
Bq m -3 ) concentrations of radon were found in hillside locations. On the other hand, the median (27
and 43 Bq m -3 ) and maximum (626 and 1002 Bq m -3 ) values of calculated indoor radon
concentrations exhaled from construction materials were the highest at the ground level places. On
the average only from seven to nineteen percent of the radon seemed to originate from the
construction materials.

Key words: radon concentration, indoor, materials, underground, ground level, workplaces