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Radon Action Month in Canada Published: ()

November is Radon Action Month. There is no better time to start testing your home and ensuring that the air you breathe is safe for you and your family.

What is radon and where can I find it?

Radon is an invisible radioactive gas that causes lung cancer. In Canada, it is the second highest cause of lung cancer, after smoking. It comes from the ground and is produced by the breakdown of the mineral uranium that occurs naturally in the soil. As uranium breaks down, it eventually releases radon. Radon is a gas, so it travels easily through the soil, working its way toward the surface.

When radon escapes into outdoor air, the concentrations are low (approximately 15 Bq/m3). However, radon also escapes into our homes wherever they’re in contact with the soil, finding its way in through cracks or around pipes and drains. Here in Canada, our homes are well sealed to keep us warm in the winter, and so the radon concentration in our homes can easily build up.

Canada is one of several countries with high levels of radon. Saskatchewan, Manitoba, New Brunswick and the Yukon are regions within the country that have radon levels that are comparable to some of the highest levels around the world, such as in the Czech Republic, Finland, Mexico and Sweden. However, every region in Canada has homes with elevated radon, so it’s worthwhile testing your home. The percentage of homes with high radon levels are presented in the map below, developed by Colin Gutcher and the radon technical operations group at the Radiation Protection Bureau.


The percentage of homes with high radon levels in City of Ottawa Health Unit is 7%. In Canada, radon is the second highest cause of lung cancer, after smoking. November is Radon Action Month - there is no better time to start testing your home and ensuring that the air you breathe is safe for you and your family.

This map was created using data collected from the Cross-Canada Radon Survey (2011) and the Radon Thoron Survey in Canadian Metropolitan Areas (2013). Collected information is grouped by Health Region. Boundary files are sourced from Statistics Canada, 2018. Map produced by Radiation Protection Bureau, Health Canada, 2019. *A high radon level is defined as a radon level that is greater than the Health Canada guidelines for indoor radon, 200 Bq/m3.

How do you find out the radon level in your home?

Simple: test your home. It doesn’t matter where you’re located or what the levels are in your neighbours’ homes. It doesn’t matter whether your home is old or new, small or large. While it’s true that some communities have higher than average radon levels, each house is different and high radon levels can be found anywhere. If you do detect radon in your home, contact a certified radon professional to determine the most effective way to manage the issue.

What is the benefit of removing radon from homes?

The big benefit is to help prevent lung cancer. More than 3,000 lung cancer deaths are attributable to radon in Canada each year, and removing radon from homes can reduce that number. Dr. Janet Gaskin, an epidemiologist at Health Canada, has conducted research to assess the risk from radon in homes. “Radon mitigation is easy to do,” says Dr. Gaskin. For example, installing radon preventive measures in new homes reduces radon entry. According to estimates, 453 fewer lung cancer deaths could be prevented every year in Canada if all new homes included radon reduction systems. If high levels of radon are measured in existing homes, a very effective technique called an active soil depressurization system can reduce radon by about 90%, and this would prevent even more lung cancer deaths every year.

“Unfortunately, lung cancer is still characterized by low survival rates,” reminds Dr. Gaskin. “Research suggests that radon prevention in new housing is very cost effective in every region of Canada and that testing and mitigation of high levels in existing housing is cost effective in higher radon regions.”

Testing your home for radon is easy to do and all homeowners are encouraged to test the radon level in their homes and to take action to reduce it if the level is high. After all, it could save lives!

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