EN
In 2000-07 653 measurements of radon were acquired from houses in Podlasie Province, Poland. In dwelling parts of buildings, arithmetic weighted mean regarding location of the building equal to 72 Bq/m3, which corresponded to 1.8 mSv of the effective dose. Statistically significant differences between radon concentrations in country and city houses were observed. Arithmetic mean of radon concentrations in dwelling parts of houses in rural areas was 111 Bq/m3, while in the city it was 45 Bq/m3. Correlation between radon concentrations in a house and its age was observed. The correlation coefficient was 0.3 at p<0.05.