EN
Radon-222 concentration in surface water, wells water and tap water in the main towns and villages which are located in area of Izera Plateau has been quantitative determined. The measurements were performed using the alpha liquid scintillation counting method. The main waterworks in Szklarska poręba is supplied with the surface water in which the radon concentration is low: from 1,23 Bq/l to 4,32 Bq/l. Waterworks "Huta Julia" is supplied with the ground water have a high radon concentration: from 294,4 Bq/l to 319,5 Bq/l. Majority of waterworks in Izera Plateau is supplied with the ground water in which the radon concentration is high: from 113,3 Bq/l to 464,5 Bq/l. The appropriate mean value for water of individual wells was 253,0 Bq/l, within the range from 25,8 Bq/l to 1095,1 Bq/l.