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Learn about radon and the harmful effects it can have on your health if found in your home.
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Take Action on Radon

What is radon?

Radon is a radioactive gas found naturally in the environment. It is colourless, odourless and tasteless. Radon is formed from the breakdown of uranium, found in soil, rock and groundwater.

Outdoors, the open air dilutes radon seeping from the ground to such low concentrations that it does not pose a concern. When radon enters an indoor space, such as a home, it can build up to high levels and pose a health concern to the people living there.

The Canadian Radon Guideline from Health Canada recommends the level of radon in the air of a home be no more than 200 Becquerels per cubic metre (Bq/m3) per year.

What are the health effects of radon?

  • If inhaled, radon particles can damage lung tissue
  • Radon exposure increases the risk of developing lung cancer
  • Exposure to both radon and tobacco smoke significantly increases your risk of lung cancer
  • Risk of lung cancer depends on:
    • the level of radon in your house
    • length of exposure
    • whether you smoke
    • exposure to second-hand tobacco smoke

How can radon get into my home?

Over time radon can seep into a house through windows, plumbing, or cracks in the foundation.

How do I test for radon in my home?

Visit Take Action on Radon (external link) to find out how to test for radon in your home.

How can radon get into my home?

Diagram of radon movement

To learn more, visit the Government of Canada's Radon page.