Radon: the invisible health risk
Radon has been recognized as a health risk to the general public for more than 25 years. The risk arises from long-term exposure to this naturally occurring radioactive gas in residential buildings. Radon accounts for about 10% of all lung cancer cases in Canada. It is the major risk factor in the nonsmoking population and significantly enhances the risk for those who do smoke.
In BC, the interior regions have been identified as being prone to elevated levels of radon in homes and other buildings (see radon map for BC at the BC Centre for Disease Control web site: www.bccdc.org/content.php?item=69). In contrast, coastal areas show relatively low levels in homes. Several factors affect the level of radon in buildings, including the concentration of natural radioactivity in local soil, building design features, heating and ventilation methods, as well as weather conditions. The only way to determine if radon is present in significant amounts is to test the building air.
Home owners can readily obtain simple radon test devices and take their own measurements. The BCCDC web site has details on testing methods and suppliers of test device services. The most effective method to reduce radon levels involves installing piping and a fan to extract the radon from under the building concrete floor slab and venting the gas to outdoors.
In 2006 Canada’s national Radiation Protection Committee developed an updated radon guideline for dwellings, with a new, lower action level to replace the outdated 1987 guideline. A government action plan was developed to implement the guideline. This includes working with building inspectors, the construction industry, and other professionals on prevention in new building construction and enhancing services available for radon testing and building remediation. Changes will be made to the national building code on radon-proofing techniques.
—Brian Phillips, Program Director
Radiation Protection Services, BC Centre for Disease Control