Is Radon Gas a Problem in Calgary?

by | Sep 1, 2022

What is Radon?

As a homeowner in Calgary, you may have heard the term “radon” floating around, but what exactly is radon gas and why should you be concerned about it? Radon is a naturally occurring gas that is produced by the radioactive decay of the element radium. Radioactive decay causes atoms to break down and form other elements by losing atomic particles (protons, neutrons, or electrons). Radon, which itself is part of the Uranium decay chain, further breaks down into the element polonium and final stabilizes in the form of lead. With each of these decays is primarily the emission of alpha radiation. When occurring inside the lungs these high energy alpha emissions can cause damage to lung tissue and can contribute to the development of lung cancer.

Where Does Radon Come From?

Radon gas is colourless and odourless, so it doesn’t always provide obvious warning signs when it exists in your home. However, long-term exposure to high levels of radon can increase your risk for lung cancer. Due to this danger, testing for radon levels in homes has become standard practice in many areas across the country. Radon primarily enters the home through the basement or crawlspace via soil gas emissions. As soil beneath the structure emits gas through process of Uranium (naturally occurring in soil) decay, Radon gases that are emitted can utilize cracks or small spaces around penetrations in the floor or slab to seep their way into a home.


Radon Soil Gas

Is there radon gas in Calgary?

Radon potential maps for Canada indicate that most of Alberta, and specifically Southern Alberta is in a High Radon Potential zone. Calgary falls into this Zone 1 – High potential area. While this doesn’t guarantee that Radon will be a problem in your home it is highly suggestive that you should at least test for Radon gas in Calgary. If that doesn’t convince you I recommend tuning your radio in to the Fan 960 while you’re stuck on Deerfoot as they regularly run Radon informative advertisements. 


How to test for Radon?

You can test for radon gas levels using an at-home test kit (check for C-NRPP approval) that measures levels over time or you can use a professional service to test for readings. Keep in mind that even if your home does not contain high levels of radon initially, those levels may change over time due to shifting soil composition or changes inside your walls or foundation structure. Over time radon emitted from the soil under houses can accumulate inside a home, particularly in well insulated air-tight homes of newer construction. While more energy efficient these types of homes leave little openings for Radon to escape.

Regular testing can help you stay on top of any potential changes in these levels and make sure that they remain at safe levels. Radon gas can pose real health hazards if left unchecked—but thankfully there are ways we can protect our homes occupants. Testing for elevated radon levels is recommended every 2 years. This will help ensure that any changes in concentration over time are caught promptly, and appropriate action can be taken.



Radon Mitigation

If a test reveals elevated radon levels in your home, there are steps you can take to reduce those levels and keep your family safe from the risks associated with exposure to this dangerous gas. The most common method of reducing radon involves creating ventilation pathways within your walls or foundation structure that allow the gas to be directed outside before it reaches dangerous concentrations inside your living space. This process involves sealing cracks and openings around pipes, vents and other objects as well as installing fans or other systems to draw out any trapped air containing high concentrations of radon before it breaches your home.



What are Safe Radon Levels?

Unfortunately, there are no safe levels of Radon exposure but there is a correlation between exposure levels and the risks of developing lung cancer. Personal risk tolerance will determine how you handle radon mitigation. To make the most informed decision you first need to understand the risks of radon exposure and what your personal exposure levels are. However, for reference – Health Canada recommends taking action for radon levels exceeding 200 Bq/m3, while the United States has a lower threshold of 148 Bq/m3. Finally, the World Health Organization suggests limiting exposure to 100 Bq/m3. Regardless of the governing body you seek for advice the consensus is that less exposure is better. The following table provides further information on the relationship between exposure levels and inherent risk:



radon risk factor



Radon Level
 If 1,000 people who have
never smoked were exposed to this level over a lifetime…
 If 1,000 people who smoke were exposed this level over a lifetime…
20 pCi/L or 740 Bq/m3 approx. 36 of them
would develop lung cancer.
approx. 260 of them
would develop lung cancer.
Mitigate the exposure level.
10 pCi/L  or 370 Bq/m3 approx. 18 of them
would develop lung cancer.
approx. 150 of them
would develop lung cancer.
Mitigate the exposure level.
8 pCi/L or 296 Bq/m3 approx. 15 of them
would develop lung cancer.
approx. 120 of them
would develop lung cancer.
Mitigate the exposure level.
4 pCi/L or 148 Bq/m3 approx. 7 of them
would develop lung cancer.
approx. 62 of them
would develop lung cancer.
Mitigate the exposure level.
2 pCi/L or 74 Bq/m3 approx. 4 of them
would develop lung cancer.
approx. 32 of them
would develop lung cancer.
Consider Mitigation if level is
between 2 and 4 pCi/L.
1.3 pCi/L or 48 Bq/m3 approx. 2 of them
would develop lung cancer.
approx. 20 of them
would develop lung cancer.
Understand that reducing levels
below 2 pCi/L is difficult, and that this level represents the average indoor range for Radon.
0.4 pCi/L or 14.8 Bq/m3 —————– —————– Understand that reducing levels
below 2 pCi/L is difficult, and that this level represents the average outdoor range for Radon.

 Information in this article provided in part by InterNACHI®.










The only way to be certain if you have an issue with Radon gas in Calgary – is to test for it. From there you will need to decide if Radon mitigation action is necessary. If not, be sure to re-test regularly (every 2 years) to ensure you, and your families remain safe from harmful exposure.