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Written by Dave Murray -
OVRXRadon is a natural gas derived from uranium found in the soil that is odorless, tasteless and invisible. It seeps out of the ground and enters the home usually through cracks and crevices in the basement and can affect other areas of the home.
In the open air, the amount of radon gas is very small and it does not pose a health risk. However, in some confined spaces like basements and underground mines, radon gas can accumulate to relatively high levels and can become a health hazard. Exposure to high levels of radon has been associated with an increased risk of lung cancer, depending on the length of time you are exposed.
The Environment Protection Agency (EPA*) has found that radon is responsible for over 20,000 deaths per year in the United States. Health Canada ** estimates that over 1,600 Canadians die each year from exposure to radon in their homes. (Source: Natural Resources Canada) Radon is prevalent in most parts of the United States and Canada. Check the information sources with Health Canada and the EPA for regions that are prone to naturally high concentrations of radon gas.
Radon remains in the home due to poor ventilation that can be the result of an airtight construction that is sealed tightly against excess air infiltration from the outside. Providing adequate air change per hour in homes, including unfinished basements and finished basements, is a remedy to prevent excessive accumulation of radon. (ASHRAE***) Fresh air ventilation will also help avoid indoor air quality problems, such as elevated levels of dust and other allergens and carbon monoxide, ozone and other indoor air pollutants. In addition, with air change in the basement, excess moisture will evaporate, naturally helping to prevent the growth of mold and fungus on moist surfaces.
Canadian (CMHC ****) and United States (EPA*) government information available free to homeowners indicates that high radon levels are not widespread in all homes. However, it is difficult to predict the level in any one home. If homeowners are concerned about exposure to radon gas in their homes, radon levels can be tested. Commercial services are available to homeowners for approximately $250 to measure radon levels in their homes and radon test kits are available on the Internet for approximately $50.
The following basement finishing ideas will help reduce radon in the home:
Renovate the existing basement flooring, particularly earth floors, with a concrete pad topped with an air gap basement subfloor system;
Seal cracks and openings in basement walls and floors, and around pipes and drains;
Ventilate the basement subfloor system. With a basement subfloor system, such as the Barricade modular subfloor system, it is possible to ventilate underneath the subfloor with a separate ventilation duct linked to a fan that draws fresh air in, blows it across the basement concrete flooring and then exhausts it out the other side of the basement.
Resources
article at HomeRenovationGuide.com