Radon is a radioactive gas that comes from the breakdown of uranium in soil and rock. It is invisible, odourless and tasteless. When radon is released from the ground into the outdoor air, it is diluted and is not a concern. However, in enclosed spaces, like homes, it can accumulate to high levels and become a risk to the health of you and your family.
Scientists believe the principal source of radon in homes is from the soil in contact with basement floors and walls. To reduce the radon risk you should first test the air in your home to determine the radon level.
While natural rocks such as granite may emit radiation and radon gas, the levels attributable to such sources are not typically high.
How Radon Gas gets into your home
The air pressure inside your home is usually lower than in the soil surrounding the foundation. This difference in pressure draws air and other gases, including radon, from the soil into your home.
Radon can enter a home any place it finds an opening where the house contacts the ground: cracks in foundation floor and walls, construction joints, gaps around service pipes, support posts, window casements, floor drains, sumps or cavities inside walls.
Radon levels in Canada
Uranium is a common element found everywhere in the earth’s crust, as a result radon gas can be found in almost all homes in Canada. Concentrations differ greatly across the country, but are usually higher in areas where there is a higher amount of uranium in underlying rock and soil.
Radon concentration levels will vary from one house to another, even if they are similar designs and next door to each other. The only way to be sure of the radon level in your home is to test.
If your home has a radon level of 4 picocuries per liter (pCi/L) of air or more, you should take steps to fix your home and reduce the radon level.
If your radon level is below 200 no action is required.
For radon levels above 200, take action to reduce. Call 1-866-225-0709 or visit Canada.ca/radon. Depending on the test level you may need to hire a qualified radon professional to fix or mitigate your home.
The key to reducing your risk of lung cancer from radon is to test your home and mitigate when necessary. A specially-trained and qualified radiation professional may be equipped to test for other radon sources (such as granite or diffusion from drinking water) when diagnosing the nature and source of your home’s radon problem.