Is your home radioactive? Checking up on radon

Radon is a radioactive gas that is produced naturally by the breakdown of uranium in the ground. It can seep into your home through cracks, openings or gaps in the foundation walls or floors. Since there are no areas in the country that are “radon-free”, the question isn’t if radon is in your home, it’s how much?

“It’s surprising when you see the data, it speaks for itself,” says Pawel Mekarski, Head of the Radon Technical Operations Section at Health Canada. “If you look at all the sources of radiation, radon represents about 50% of an individual’s lifetime radiation exposure.”

There are trace amounts of radioactivity in almost everything. Since radon is colourless, odourless and tasteless, the only way to know is to test. The same uranium that produces radon is found in common objects and building materials, and it doesn’t usually cause any issues. However, radon is a gas that emits a particularly harmful type of radiation, which is known to cause cancer. This radiation is harmless outside the body, but since radon is a gas, it can easily enter our lungs. Once you breathe it in, it can directly affect your lungs, which makes it the number one cause of lung cancer in non-smokers.

“In Canada, we can attribute more than 3,000 deaths per year to radon,” says Pawel. “Everyone in Canada is exposed to it.” That is more than the number of deaths from car accidents or house fires put together!

Although radon is present in the air, when it’s outside it doesn’t present a health risk because it is diluted and is only present at low levels. The problem comes when radon builds up to high levels in places where we spend lots of time (at home or at work indoors).

Since the air pressure inside a house is usually lower than the pressure underneath or around the foundation, it acts like a vacuum to draw radon in through the foundation cracks or openings. Once inside the house, radon can build up to dangerous levels. If your home is over the threshold of 200 Becquerels per cubic meter (the unit used to measure radiation), Health Canada recommends that you take action.

The importance of testing

“Radon testing is evolving,” explains Pawel. “We are looking at the effectiveness of detectors in order to provide the best advice possible.” In fact, Health Canada even recalled (see here and here) some ineffective radon detectors recently, because they were found to provide false information and a false sense of security to users.

The best way to test is to conduct a long-term study in your home. To get the most accurate reading, Health Canada recommends leaving the radon detector in your house for at least 3 months, ideally in the winter when your windows and doors are closed more often. The goal is to get an accurate representation of the average annual radon level. Find out more at:

Some digital radon monitors, or even continuous radon monitors, are also making their way onto the market. Health Canada considers these to be screening tools that can help get a sense of whether or not radon is an issue in your home. “We are working with industry on a certification program for these, but quality could vary and people should be careful when interpreting the results. A long-term test remains the best way to test for radon in your home,” cautions Pawel.

Don’t forget to reduce!

By making our homes more and more energy efficient, we end up trapping the radon that seeps in from the ground. Pawel’s group is working to update Health Canada’s guidance on radon and to provide information to provincial, territorial and municipal partners to improve the building codes across the country.

In the meantime, if the results of the tests reveal that radon levels in your home are above the guideline, it’s important to take action to reduce the radon levels. You can call on a professional who can complete the work in a day, for less than the cost of replacing your furnace or air conditioner. The process involves installing a pipe that travels from the ground to the outdoors, with a fan to draw the air up. It’s that simple, and it makes the air you breathe safer for your family.

“Research shows us that radon levels are actually increasing across Canada. Everyone needs to test their home, and act on the results if needed,” says Pawel.

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