driven housing guidelines for energy efficiency should have less of an effect on
residential radon concentrations. However, if outdoor make-up air, with increased air
pollutants, is used to reduce residential radon concentrations, indoor air quality may
suffer unless the air is filtered prior to use.
Weather-related influences
Numerous weather-related factors influence the ingress of radon into buildings
including wind, barometric pressure, temperature, and rainfall. All of these factors will
potentially be influenced by climate change to differing degrees based on geography.
For example, increased wind can exert small pressure differences between the lower
levels of a dwelling and the outdoors (Steck 2009). Increased precipitation can also act
to impede radon emanation, “capping” the soil outdoors and directing it toward the
unsaturated soil near or under the building. In addition, if the soil is not saturated, low
and moderate levels of soil moisture provide a greater radon source that can penetrate
through holes in the substructure of a building (Schumann et al. 1989).
High Density Housing
Many cities and urban areas are moving toward a higher percentage of high
density housing driven by population increases as well as efforts to reduce greenhouse
emissions. Condominiums and other high density type housing units are often
constructed of concrete including some units with concrete construction on all sides
(i.e., walls, ceiling, floor). While the radium content of the concrete is not high, the large
concrete surface area and low air exchange rates in the units have contributed to
elevated radon exposures for some occupants (Lawrimore 2010, Broadhead 2008).
Concrete, as a source of radon exposure, may be an increasing problem as more high
density housing is constructed.
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