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Pollution & air quality

Indoor air quality


You should test your home for radon, an invisible gas that can cause lung cancer. Testing for radon is easy and costs about $50. If your home has high radon levels, you can repair it to block the radon.

What is radon?

Radon is an invisible, odorless gas that can seep into your home through cracks in floors, walls and foundations. You can't see radon. You can't smell it or taste it. But it may be a problem in your home.

Radon comes from the natural breakdown of uranium in soil, rock and water. Radon gas escapes from the ground into the air outside. When radon mixes with the air outside, itís not a problem: the air outside dilutes the amount of radon. But when radon seeps into a closed-in space like a house, it can be harmful. The radon gas can become trapped inside. You and your family can breathe in high levels of radon, without knowing it.

How does radon get into my home?

Radon can come out of the soil and water and seep into cracks and openings in your home, especially on the lower floor, basement, or crawlspace. Radon gas can get into your home through many openings, including:

  • unfinished floors
  • pipes
  • windows
  • sump pumps
  • cracks in the basement floor or foundation

Radon can get trapped inside your home, especially in basements and crawlspaces that donít have good ventilation (air movement).

How can radon hurt my health?

Radon is the second leading cause of lung cancer in Canada. Radon exposure is estimated to be the cause of 16% of lung cancers.

If you live in a building with high radon levels (or if you spend a lot of time in one), you are at higher risk for lung cancer. Radon is the second most common cause of lung cancer, after smoking.

If you smoke and you live in a home with a high level of radon, you are at an even higher risk for lung cancer.

How does radon gas cause lung cancer?

Radon decays quickly, giving off tiny radioactive particles. When inhaled, these radioactive particles can damage the cells that line the lung. Long-term exposure to radon can lead to lung cancer.

How do I know if thereís radon in my home?

The only way to know if your home has radon is to test for it. You canít see, smell, or taste radon.

Radon can be found all over Canada. There are parts of the country that tend to have more radon, and parts that tend to have less. But itís impossible to know how much radon there is in your home unless you test for it. That's why everyone should test their home for radon.

How do I test my home for radon?

You can test you home for radon in two ways:

What kind of radon test should I get?

The best kind of radon test is a long-term test. Long-term radon tests take about three months. Long-term radon tests are much more accurate than short-term tests.

The Lung Association does not recommend any particular brand of radon test. Just be sure to get a long-term radon test.

Where do I buy a radon test?

You can probably find a radon test in a local hardware or home improvement store. If you canít find one at store near you, you can buy one online.

When should I test for radon?

Itís best to test for radon over the winter months, when there is less ventilation (less air movement) in your home.

How do I use a home radon test?

Follow the instructions that come with your radon test.

In general, you:

  • Put the test device on the lowest level of your house that you use regularly (the level where you spend four hours a day or more). This could be your basement or your main floor.
  • Make sure the test device is in a safe place, where it wonít get knocked over.
  • Leave the test device in place for at least three months.
  • Mail the test device to the companyís laboratory. The test will come with a mailing label and package. All you have to do is put the test device in the package and drop it in a post box.
  • The company will analyze test device in their laboratory and mail you the results.
What do I do if the test results say I have radon in my home?

What you do depends on how much radon there is. Radon is measured in Becquerels per cubic metre (Bq/m3).

  • If your homeís radon level is less than 200 Bq/m3, Health Canada radon guidelines say that no action is required. However, even low levels of radon can be harmful. Itís a good idea to try to lower your homeís radon level as much as possible, even if itís already below 200 Bq/m3.
  • If your homeís radon level is between 200 and 600 Bq/m3, you should repair your home in the next two years.
  • If your homeís radon level is over 600 Bq/m3, you should repair your home within one year.
How do I repair my home to lower its level of radon?

To lower the radon level, you need to hire a contractor to:

  • figure out where the radon is coming in
  • do repairs to block it from coming in.

Radon can come into your home through: sump pumps, cracks in foundations, spaces around pipes, unfinished floors, and other places. To solve your radon problem, you need an expert to find out where exactly the radon is getting in. A trained contractor with experience in radon mitigation (radon repairs) can examine your home, find where the radon is seeping in, and make the necessary repairs.

Who should I hire to repair (mitigate) my home to lower its radon level?

You should hire an experienced, reputable contractor to mitigate your home. Contact Canadian National Radon Proficiency Program (C-NRPP) at 1 800 269-4174 or on the website for a list of certified service providers who can help reduce the level of radon in your home.

How much will it cost for repairs to block radon (radon mitigation)?

It usually costs between $500 and $3000 to repair your home to block radon from getting inside.

Are there any grants or programs that cover the cost of radon testing or mitigation (repairs)?

No, unfortunately. We are not aware of any grants to cover the cost of radon testing or mitigation.

What if I rent my home? Can I ask my landlord to test for radon?

We do not know of any specific laws that force private landlords to test for radon or make repairs. If you rent, you could ask your landlord to test for radon. If your landlord refused, you could try testing for radon yourself. After you got the results, you could share them with the landlord. If the results said your rental home does have a high level of radon, you could ask your landlord to hire a radon mitigation contractor.

Lung cancer patient urges homeowners to test for radon : Read Antonellaís story

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