Investigation of the in fl uence of chamber construction parameters

Radon (222Rn) is a naturally occurring radioactive gas that originates from the decay of radium (226Ra) in the primordial uranium (238U) decay series. As a noble gas, it easily migrates through inter-granular spaces; then, because of advection, diffusion and convection with other gasses or with water, it moves through fi ssures and faults until it reaches the outdoor atmosphere. Its half-life is long enough that it can migrate even to quite long distances from the place of its decay into buildings raised in a certain area. According to Nazaroff and Nero [1], this distance in soil and rocks can be as long as a few metres. This is the reason that radon and its decay products are the main source of ionizing radiation in non-industrial buildings. They are responsible for about half of the radiation dose people in Poland are exposed to [2]. The effects leading to the presence of radon in fl ats and buildings are emanation, transport (mainly diffusion-advection) and exhalation. All these processes were already extensively examined and they are well understood in theory ([1] and references herein). However, in practice, the parameters such as emanation coeffi cient, diffusion coeffi cient and exhalation rate that describe the mentioned effects are affected by many environmental factors [3, 4]. Investigation of the infl uence of chamber construction parameters on radon exhalation rate Beata Kozłowska, Jadwiga Mazur, Krzysztof Kozak, Agata Walencik-Łata, Błażej Baic