Some indoor air pollutants are obvious. Others are invisible, but that doesn’t mean they’re harmless. Radon is one example that is more common than people realize. If you live in a home with a basement, you might consider having your home tested. Here’s why you should, and what you can do to reduce your exposure.

What is Radon?

Radon is a colourless, odourless radioactive gas that is naturally released from bedrock, soils and groundwater across North America. When it is released into the air, it is sufficiently diluted and does not pose a health concern. However, when it gets inside enclosed areas (like a home), concentrations can reach levels that exceed health guidelines.

What are the health risks with Radon?

Radon is the second leading cause of lung cancer, next to smoking. The risk of developing cancer depends on how much radon is in the air you breathe and the length of time you’re exposed. While not everyone exposed to radon will develop cancer, 16% of lung cancer deaths in Canada are attributed to radon exposure.

How to test for Radon

Health Canada has studied radon levels across Canada, and levels vary significantly from province-to-province. However, regardless of provincial averages, there are areas across the country with radon levels that exceed guidelines. Therefore, it is recommended by both Health Canada and US EPA that every home be tested for radon.

Radon test kits are available online or from hardware stores. Tests of at least 3 months in duration are recommended, and should be taken in the fall/winter months when radon levels are higher. Learn more about where to get test kits in Canada here and the US here. Always follow directions provided by the manufacturer to get the best results.

What should you do if your home exceeds Radon level guidelines?

Radon levels are measured in “becquerels per cubic metre” (bq/m3). Health Canada advises that indoor levels should not exceed 200bq/m3. If your home test shows levels that exceed this, you have a few options. If you are building a new home, consider discussing with your contractor measures they can take to mitigate exposure as it is much easier to address radon reduction during the construction process then waiting until the home is built.

If you are in an existing home and radon concentrations are 200 – 600bq/m3, consider taking remedial action within the next 2 years. If levels exceed 600bq/m3, remedial action should be taken sooner if possible.

Reducing radon in the home is typically done most effectively with help from a certified service provider. The most common method is to install a pipe under the basement slab and vent the gas either out a side wall or through the roof. Sealing entry routes (i.e. basement wall penetrations and cracks) and increasing ventilation can also help. Consider using a sealant to reduce radon migration through porous concrete (such as RadonSeal).