Investigation of the influences of atmospheric conditions on the variability of radon and radon progeny in buildings

Analysis of time-series data sets, collected in vernacular buildings and workplaces linked with radium source bedrock has identified a number of internal and external pressure characteristics linking meteorological parameters with the variability of radon gas and its progeny. The cellars in these buildings are excavated from the bedrock associated with the radium source and have relatively high levels of radon concentration along with largely stable microclimatic conditions, which differ from those of the buildings’ ground and upper levels. In workplace environments cyclical characteristics are apparent, associated with heating and ventilation related to working hours. Comparative radon concentration data, collected within buildings and similarities identified between buildings, suggest the need to distinguish between short and longer-term influences. From a range of comparative data studied, water vapour pressure, a partial pressure of barometric pressure, is indicated as a principal determinant of the short-term variability of radon gas concentrations, with barometric pressure determining the trend or general longer term level, both linked to temperature. Wind speed appears to have the potential for a dual influence on radon variability: directly, through wind pressure differences and indirectly, through changes to the water vapour component.