Radon is a colourless, odorless, radioactive gas that occurs naturally in the environment. It comes from the natural breakdown of uranium in soils and rocks. Exposure to high levels of radon increases the risk of developing lung cancer. This relationship has prompted concern that radon levels in some Canadian homes may pose a health risk.
Radon gas can move through small spaces in the soil and rock upon which a house is built. It can seep into a home through dirt floors, cracks in concrete, sumps, joints, basement drains, under the furnace base and jack posts if the base is buried in the floor. Concrete-block walls are particularly porous to radon and radon trapped in water from wells can be released into the air when the water is used.
A survey conducted by Health Canada in the 1970s showed that radon levels in certain Canadian cities were higher than in others. However, these same studies showed that it is impossible to predict whether any one house will have a high level of radon. Factors such as the location of the house and its relation to the prevailing wind may be just as important as the source of the radon.
Commercial services are available to homeowners who wish to measure radon levels in their homes. Radon is measured in units called “becquerels per cubic meter”. The most popular radon detectors are the charcoal canister, the electrets and the alpha track detector. These devices are exposed to the air in a home for a specified period of time, and then sent to a laboratory for analysis. There are other techniques for testing radon levels, but they require a trained operator and are more expensive.
Homeowners may want to reduce their exposure to radon, regardless of levels tested. Some of the steps you can take to reduce radon levels in your home include:
- Renovating existing basement floors, particularly earth floors.
- Sealing cracks and openings in walls and floors, and around pipes and drains.
- Ventilating the sub-floor of basement floors.
Health Canada and the Canada Mortgage and Housing Corporation have produced a booklet called Radon – A Guide for Canadian HomeownersTo order a copy, call 1-800-668-2642. The call is toll-free in Canada.
SOURCE: HEALTH CANADA
