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COVID-19 and Buying a Radon Test Kit

At this time radon test kits are not available through the Health Unit as we are providing essential services only due to our ongoing response to the COVID-19 pandemic. We anticipate that we will be able to resume sales of radon test kits later this year. Please watch for updates on our Facebook and Twitter pages and our website. The best time to conduct your radon test is during the heating season. Radon levels vary from day-to-day and from season-to-season. The highest radon levels are generally found during the fall and winter when our homes are sealed more tightly than during the summer months. If you have already performed your radon test, or are in the process of performing your radon test, you should have received, or will be receiving your test results through the method indicated in your testing kit. The testing laboratory is still functional and able to provide you your test results via email. If you have questions regarding your test results, you can email or call 1-800-660-5853.

October 23, 2019 Media Release: November is Radon Action Month

The Leeds, Grenville and Lanark District Health Unit encourages residents of Lanark County and the United Counties of Leeds and Grenville to test their homes for radon.

Radon test kits can be purchased from reception at our Brockville, Smiths Falls, Gananoque (cash only), Almonte (cash only), and Kemptville (cash only) offices for $20.00 (postage to mail the kit away for testing will cost between $7-10). Please note that each office has different office hours. This is a discounted price available to residents within our Health Unit area. For more information, contact us at or call 1-800-660-5853.

Follow our Facebook and Twitter pages for occasional free test kit giveaways and stay tuned to our website for dates of future community information sessions.

What is Radon?

Radon is a naturally occurring colourless, odourless and tasteless radioactive gas that forms when uranium breaks down in soil, rock and water. It can be found at high levels in buildings all over Ontario, including in Lanark County and the United Counties of Leeds and Grenville. When radon is released from the ground outside it gets diluted by fresh air and is not a concern. When radon enters indoor areas through floors, holes, and cracked foundations it can accumulate to higher levels and be a risk to our health.

What are the health effects of Radon?

Long-term exposure to elevated radon levels can cause lung cancer. Radon is the second leading cause of lung cancer overall (behind smoking) and the leading cause of lung cancer in people who do not smoke. Approximately 850 Ontarians die each year from lung cancer caused by radon exposure. The risk of lung cancer due to radon increases with the duration of exposure and the level of radon. The risk is even higher in some groups, such as those who smoke. Children are also at higher risk due to their natural faster breathing rate and their greater potential for long-term exposure. Reducing long-term exposure to radon can decrease your risk of developing lung cancer.

Should I test for Radon?

Yes. The only way to know if radon is a problem in a building is to test.

How do I test for Radon?

There is a simple test that can check your home (or any building) for radon. Test kits are available from the Leeds, Grenville and Lanark District Health Unit at a discounted price, online, or from some building supply and hardware stores. Testing instructions are provided in every kit. These kits should be placed on the lowest level of the home (where someone spends a minimum of 4 hours per day) for at least 3 months during the fall or winter (when the windows are closed and the home is the least ventilated) to measure an average radon level. A professional radon testing company can also be hired to complete a radon test.

What does my test result mean?

The higher the radon level, the higher your risk of developing lung cancer with long-term exposure. Health Canada recommends remedial action for radon levels that are above 200 Bq/m3, targeting the lowest radon level achievable in your home. A public health inspector at the Health Unit can help you interpret your test results and decide whether consultation with a certified radon mitigation professional is necessary. Public Health Inspectors can be contacted at 1-800-660-5853 or

When do I need to reduce the radon in my home?

Health Canada recommends:

  • If your test shows radon levels between 200–600 Bq/m3, fix your home within two years
  • If your test shows radon levels above 600 Bq/m3, fix your home within one year

How do I reduce radon in my home?

Mitigation measures are available, affordable, and effective and will reduce your risk of developing lung cancer due to radon exposure. Hiring a professional certified in radon mitigation is the best way to reduce radon levels in your home. Local radon mitigation professionals can be found at Ensure to check with your municipality about potential building permit requirements for radon mitigation work.