title: Hierarchical modeling of indoor radon concentration: how much do geology and building factors matter?
abstract: Radon is a natural gas known to be the main contributor to natural background radiation exposure and only second to smoking as major leading cause of lung cancer. The main concern is in indoor environments where the gas tends to accumulate and can reach high concentrations. The primary contributor of this gas into the building is from the soil although architectonic characteristics, such as building materials, can largely affect concentration values. Understanding the factors affecting the concentration in dwellings and workplaces is important both in prevention, when the construction of a new building is being planned, and in mitigation when the amount of Radon detected inside a building is too high. In this paper we investigate how several factors, such as geologic typologies of the soil and a range of building characteristics, impact on indoor concentration focusing, in particular, on how concentration changes as a function of the floor level. Adopting a mixed effects model to account for the hierarchical nature of the data, we also quantify the extent to which such measurable factors manage to explain the variability of indoor radon concentration.
authors.affiliation: Department of Economia, Metodi Quantitativi e Strategie d'Impresa, University of Milano-Bicocca, Building U7, Piazza dell'Ateneo Nuovo 1, 20126 Milano, Italy. Electronic address: riccardo.borgoni@unimib.it.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Borgoni
authors.affiliation: Research Department of Infection & Population Health, UCL, London, UK.
authors.forename: Davide
authors.initials: D
authors.lastname: De Francesco
authors.affiliation: Agenzia Regionale per la Protezione dell'Ambiente della Lombardia, Milano, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: De Bartolo
authors.affiliation: Southampton Statistical Sciences Research Institute and Department of Social Statistics and Demography, University of Southampton, UK.
authors.forename: Nikos
authors.initials: N
authors.lastname: Tzavidis
mesh_terms: D000396:Air Pollutants, Radioactive / Q000032:analysis*; D016902:Air Pollution, Indoor / Q000032:analysis*; D003252:Construction Materials / Q000032:analysis*; D006798:Housing; D007558:Italy; D008962:Models, Theoretical; D011886:Radon / Q000032:analysis*; D012987:Soil / Q000737:chemistry*
chemical_list: D000396:Air Pollutants, Radioactive; D012987:Soil; D011886:Radon
keywords: Building factors; Floor effect; Hierarchical mixed models; Indoor radon concentration