What is radon?
Radon is a radioactive gas that is formed when uranium breaks down naturally. It has no colour, odour, or taste. Radon is slowly released from the ground, water, and some building materials that contain very small amounts of uranium, such as concrete, bricks, tiles and gyproc. When radon is released to outdoor air, it is dispersed into the atmosphere and is not a concern. However, in enclosed spaces like houses or other buildings, it can sometimes accumulate to high levels.
What is the current Canadian guideline for radon in indoor air?
The current Canadian guideline for radon in indoor air for dwellings is 200 Becquerels per cubic metre (200 Bq/m3).
The Becquerel is a unit that describes the radiation caused by 1 disintegration per second or radon. Individual dwelling owners may wish to reduce radon levels as much as they reasonably can, using methods they find affordable and practical. However, the level in a dwelling should not be above the Canadian guideline of 200 Bq/m3.
Radon in indoor air is a concern especially if it accumulates in enclosed spaces.
Examples of dwellings are residential homes, or public buildings such as schools, hospitals, long‑term‑care residences and correctional facilities. Workplaces are also subject to guidelines for radon. In New Brunswick, workplaces are covered under the regulations set by WorkSafeNB. For more information about radon levels in the workplace, please contact WorkSafeNB.
Are there certain parts of New Brunswick that have higher levels of radon than others?
Within the province, areas that have certain types of rock (shale and granite) and soil can have higher levels of uranium in the ground and likely more radon. This is also true of most other Canadian provinces. A radon test for an individual building is the only way to tell for certain whether radon is present. For information related to geology in your area, please contact the Department of Natural Resources.
What are the health effects of radon?
The main health risk associated with exposure to high levels of radon in indoor air is an increased lifetime risk of developing lung cancer. This is because radiation from inhaled radon gas can damage cells in the lungs. The effects depend on the levels of radon and how long a person is exposed to these levels. The Canadian guideline is based on an exposure period of about 70 years spent in a dwelling that contains elevated levels of radon 75% of that time. Exposure to radon and tobacco use together can significantly increase your risk of lung cancer, however, not using tobacco products remains the most effective way to reduce the risk of lung cancer.
How does radon enter the dwelling?
Because radon is a soil gas it can enter a dwelling through any opening that contacts the soil around or underneath the building. For example, it can seep in through cracks or holes in basement floors or walls, including openings for utility connections, and through hollow support posts. If there is radon in the dwelling's water supply, radon can also enter the space via running tap water. However, radon in water is considered a minor exposure pathway to radon. As a result, there is no Health Canada guideline value for radon in water. Both old and newer structures can have elevated levels of radon.
How can a building be tested for radon?
There are several methods that can be used to test a dwelling for radon. Here are some of the more common devices. Please note that the costs are approximate and may vary.