title: Methodology developed to make the Quebec indoor radon potential map.
abstract: This paper presents a relevant approach to predict the indoor radon potential based on the combination of the radiogeochemical data and the indoor radon measurements in the Quebec province territory (Canada). The Quebec ministry of health asked for such a map to identify the radon-prone areas to manage the risk for the population related to indoor radon exposure. Three radiogeochemical criteria including (1) equivalent uranium (eU) concentration from airborne surface gamma-ray surveys, (2) uranium concentration measurements in sediments, (3) bedrock and surficial geology were combined with 3082 basement radon concentration measurements to identify the radon-prone areas. It was shown that it is possible to determine thresholds for the three criteria that implied statistically significant different levels of radon potential using Kruskal-Wallis one way analyses of variance by ranks. The three discretized radiogeochemical datasets were combined into a total predicted radon potential that sampled 98% of the studied area. The combination process was also based on Kruskal-Wallis one way ANOVA. Four statistically significant different predicted radon potential levels were created: low, medium, high and very high. Respectively 10 and 13% of the dwellings exceed the Canadian radon guideline of 200 Bq/m(3) in low and medium predicted radon potentials. These proportions rise up to 22 and 45% respectively for high and very high predicted radon potentials. This predictive map of indoor radon potential based on the radiogeochemical data was validated using a map of confirmed radon exposure in homes based on the basement radon measurements. It was shown that the map of predicted radon potential based on the radiogeochemical data was reliable to identify radon-prone areas even in zones where no indoor radon measurement exists.
authors.affiliation: Institut national de la recherche scientifique, Eau Terre Environnement Research Centre (ETE-INRS), 490 de la Couronne, G1K 9A9 Quebec, Canada. Electronic address: jean-philippe.drolet@ete.inrs.ca.
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Drolet
authors.affiliation: Institut national de la recherche scientifique, Eau Terre Environnement Research Centre (ETE-INRS), 490 de la Couronne, G1K 9A9 Quebec, Canada.
authors.forename: Richard
authors.initials: R
authors.lastname: Martel
authors.affiliation: Institut national de santé publique du Québec (INSPQ), 945 avenue Wolfe, G1V 5B3 Quebec, Canada.
authors.forename: Patrick
authors.initials: P
authors.lastname: Poulin
authors.affiliation: Agence de la santé et des services sociaux des Laurentides, 1000 rue Labelle, J7Z 5 N6 Saint-Jérome, Canada.
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Dessau
mesh_terms: D000396:Air Pollutants, Radioactive / Q000032:analysis*; D016902:Air Pollution, Indoor / Q000032:analysis* / Q000706:statistics & numerical data; D000398:Air Pollution, Radioactive / Q000706:statistics & numerical data; D006798:Housing; D011792:Quebec; D011834:Radiation Monitoring / Q000379:methods*; D011886:Radon / Q000032:analysis*
chemical_list: D000396:Air Pollutants, Radioactive; D011886:Radon
keywords: ANOVA; Airborne survey; Geology; Radon mapping; Sediment; Uranium