Reduce the risk of the #1 cause of lung cancer in non-smokers.

Being exposed long-term to high levels of radon is the number one cause of lung cancer in non-smokers. Radon is present in almost every home and building. To find out the level of radon in your home, or any indoor space, you have to test for it.

How do you test your home for radon?

Testing your home for radon is easy.

  • Purchase a long-term radon test kit (average $30 – $50), install it on the lowest occupied level of your home during fall and winter, and leave it there for at least three months. Or, hire a certified radon professional to help you test.
  • At the end of three months, send the radon test kit to the laboratory address included with the kit. The laboratory will send a report back to you with your radon levels.

What can you do if your radon levels are above the guideline?

If your levels are above the Health Canada guideline of 200 bequerels per cubic metre of air (a bequerel is a measure of radioactive decay), you should take action to reduce the amount of radon in your home. A radon professional can offer options for what to do next, such as the following:

  • Hire a certified radon contractor to install an Active Sub-Slab Depressurization system, which is a small exhaust fan that draws the radon from below the concrete floor slab and vents it through a pipe to the outdoors. This is the solution that is likely to be most effective in reducing radon to acceptable levels.
  • Increase the ventilation in your home by hiring a contractor to install a heat recovery ventilator (HRV) or by optimizing the use of an existing ventilation system.
  • Seal all cracks and openings in foundation walls and floors.

The higher the level of radon, the sooner you should take action.

What else can you do?

Do not allow anyone to smoke inside your home. Exposure to cigarette smoke combined with high radon levels significantly increases the risk of developing lung cancer. A person who has had long-term exposure to high radon levels has a 1 in 20 chance of developing lung cancer. When combined with exposure to cigarette smoke, the risk of developing lung cancer increases to 1 in 3.

Need more information?


  1. March 2015
  2. February 12, 2014
  3. February 2013
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Health Canada Publications

  • Radon: Is it in Your Home? Information for Health Professionals. A guide to help health professionals answer their patients questions about radon.

Frequently Asked Questions (FAQ)


Mar 26, 2018

Healthy Schools Day is April 3, 2018. This Healthy Schools Day, let’s protect children and staff from a known cancer risk. Let’s rule out radon.

Jun 18, 2015

CPCHE’s Executive Director, Erica Phipps, was invited to appear before the federal Standing Committee on Health on Thursday, October 18, 2015, during the committee’s deliberations on lung cancer. Erica’s speaking notes, which feature CPCHE’s radon work in the child care sector, are available below.