Long-term Measurements of 222Rn, 220Rn, 214Pb and 212Pb Concentrations in the Air of Private and Public Buildings and Their Dependence on Meteorological Parameters
The concentration of 222Rn, 220Rn and their short-lived daughter products were measured simultaneously inside public and private buildings in Innsbruck, Austria. Approximately 750 measurements were carried out with two double-filter devices, a single-filter device and air sampling in specially designed air-bags for a period of almost 1 yr. The buildings were made out of brick, concrete, stone and wood. At all test stations the rooms were not ventilated. The concentration data, together with 24 meteorological variables, were used for a comprehensive regression analysis with a stepwise elimination of variables. It was possible to determine those variables which account for the time variation of radioactivity in the air of a given (non-ventilated) room as there are the changes of (a) the barometric pressure, (b) the soil temperature, (c) the daily mean temperature in the open atmosphere, (d) the daily mean wind speed, (e) the relative humidity, and (f) the daily range of the temperature in the open atmosphere and the absolute value of the vertical temperature gradient outdoors.