Indoor radon exposure and its correlation with the radiometric map of uranium in Sweden

AbstractFrom 2007 to 2013, simultaneous radon (222Rn) and thoron (220Rn) measurements were conducted in a total of 3534 residential homes in 34 metropolitan areas covering 71% of the Canadian population. While radon levels were above the detector’s detection limit in almost all homes, thoron concentrations were measurable in only 1738 homes. When analysis was limited to homes where thoron concentrations exceeded the detection limit, a pooled analysis confirmed that thoron is log-normally distributed in the indoor environment, and the distribution was characterized by a population-weighted geometric mean of 13 Bq/m3 and a geometric standard deviation of 1.89. Thoron contribution to indoor radon dose varied widely, ranging from 1.3 to 32% geographically. This study indicated that on average, thoron contributes 4% of the radiation dose due to total indoor radon exposure (222Rn and 220Rn) in Canada.

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The first version of the Pan-European Indoor Radon Map

Natural Hazards and Earth System Science ◽

10.5194/nhess-19-2451-2019 ◽

2019 ◽

Vol 19 (11) ◽

pp. 2451-2464 ◽

Cited By ~ 2

Author(s):

Javier Elío ◽

Giorgia Cinelli ◽

Peter Bossew ◽

José Luis Gutiérrez-Villanueva ◽

Tore Tollefsen ◽

...

Keyword(s):

Uranium Concentration ◽

Indoor Radon ◽

Grid Cells ◽

Indoor Radon Concentration ◽

Radon Exposure ◽

Bedrock Geology ◽

Distance Weighting ◽

Few Data ◽

Secondary Variable ◽

Inverse Distance

Abstract. A hypothetical Pan-European Indoor Radon Map has been developed using summary statistics estimated from 1.2 million indoor radon samples. In this study we have used the arithmetic mean (AM) over grid cells of 10 km × 10 km to predict a mean indoor radon concentration at ground-floor level of buildings in the grid cells where no or few data (N<30) are available. Four interpolation techniques have been tested: inverse distance weighting (IDW), ordinary kriging (OK), collocated cokriging with uranium concentration as a secondary variable (CCK), and regression kriging with topsoil geochemistry and bedrock geology as secondary variables (RK). Cross-validation exercises have been carried out to assess the uncertainties associated with each method. Of the four methods tested, RK has proven to be the best one for predicting mean indoor radon concentrations; and by combining the RK predictions with the AM of the grids with 30 or more measurements, a Pan-European Indoor Radon Map has been produced. This map represents a first step towards a European radon exposure map and, in the future, a radon dose map.

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Use of radon barriers to reach an acceptable radon level

E3S Web of Conferences ◽

10.1051/e3sconf/202017205003 ◽

2020 ◽

Vol 172 ◽

pp. 05003

Author(s):

Torben Valdbjørn Rasmussen ◽

Thomas Cornelius

Keyword(s):

Indoor Air ◽

Radon Concentration ◽

Indoor Radon ◽

Ventilation Rate ◽

Test Method ◽

Single Family ◽

Indoor Radon Concentration ◽

Radon Exposure ◽

Air Penetration ◽

Family House

A method is presented for theoretically estimating the necessary airtightness of a radon barrier. Radon barriers are used to balance the indoor radon concentration. To balance radon at an acceptable level, for a given ventilation rate for indoor air, a barrier must fulfil the requirements for airtightness and the indoor-air radon penetration from the soil, which is determined by the radon concentration in the soil gas. The method identifies the optimal radon barrier for a building. Ten different radon barriers are evaluated. Barriers include system solutions based on materials such as bitumen-based radon blockers, wet-room membranes, reinforced fix mortar pastes, and polyethylene membranes. The barriers are tested using a modified version of the test method NBI 167/02 radon membrane: test of airtightness. The radon barriers are evaluated for a typical building construction for a single-family house with radon exposure from the ground. An acceptable radon concentration of 100 Bq/m3 in indoor air is used in combination with a number of higher radon levels. The different radon barriers are evaluated in accordance with their ability to prevent air penetration from the ground. Furthermore, how mounting a barrier can affect the durability of a building is discussed, as the measures may create a far more vulnerable building.

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