Analysis of simultaneous time series of indoor, outdoor and soil air radon concentrations, meteorological and seismic data

Exposure to radon progenies is one of the most important sources of dose from ionizing radiation. This is especially valid in regions of the world where people spend much time indoors, because radon (here we restrict to 222Rn and its progenies and put Rn for brevity) tends to accumulate indoors compared to the outdoor atmospheric environment. This importance has led to an immense wealth of studies and literature about Rn-related issues, over the decades. Amongst topics are understanding and modelling of temporal Rn dynamics as a function of environmental control parameters and the relations between Rn dynamics in different environmental compartments at one location. It also became clear that apart from its own radiological signifi cance, Rn can serve as tracer for environmental processes and has been used in tectonic, hydrogeologic, atmospheric dispersion and climate change studies. At the National Institute of Radiological Sciences (NIRS) in Chiba, near Tokyo, Japan, a long-term experiment of simultaneous measurement of indoor, outdoor and soil Rn concentrations has been ongoing for several years (soil Rn has been added only recently), together with recording meteorological and seismic parameters. The objective is (1) description of Rn concentrations and its dynamics in different environmental compartments; (2) studying the relationships between them and with environmental controls with the aim to develop a model of it, which has explanatory and predictive capability; and (3) to investigate whether the Rn signal carries information about tectonic activity. Analysis of simultaneous time series of indoor, outdoor and soil air radon concentrations, meteorological and seismic data Mirosław Janik, Peter Bossew