Radon is a radioactive gas that is formed naturally by the breakdown of uranium in soil, rock and water. Radon is colourless, odourless and tasteless.

As a gas, radon can move freely through the soil enabling it to escape to the atmosphere or seep into buildings. When radon escapes from the bedrock into the outdoor air, it is diluted to such low concentrations that it poses a negligible threat to health. However, if a building is built over bedrock or soil that contains uranium, radon gas will be “sucked” into the building by the Stack Effect through cracks in foundation walls and floors or gaps around pipes and cables etc.

When radon is confined to enclosed or poorly ventilated spaces, it can accumulate to high levels. Radon levels are generally highest in basements and crawl spaces because these areas are nearest to the source and are usually poorly ventilated. In the open air, the amount of radon gas is very small and does not pose a health risk.

Radon is the #2 cause of lung
cancer behind smoking and account for 16% of lung cancer deaths.

Based on Health Canada’s 2010 study

How can radon affect my health

As Radon breaks down, it forms radioactive particles that can get lodged into your lung tissue as you breathe. The Radon particles then release energy that can damage your lung cells. When lung cells are damaged, they have the potential to result in cancer. Not everyone exposed to radon will develop lung cancer, and the time between exposure and the onset of the disease can take up to many years.

Long-term exposure to Radon is linked to approximately 16% of lung cancer deaths in Canada. It is the 2nd leading cause of lung cancer after smoking and the leading cause of lung cancer for people who have never smoked. If you smoke or have smoked and your home has high radon levels, your risk of lung cancer is especially high.

How it enters my home?

Stack Effect

Radon gas can enter a house any place it finds an opening where the house contacts the soil: cracks in foundation walls and in floor slabs, construction joints, gaps around service pipes and support posts, floor drains and sumps, cavities inside walls, and the water supply. Air pressure differentials across the basement slab directly affect the radon being brought into the house by means of the stack effect. Heat rising in the home creates a natural draw on the lower levels, bringing in soil gas, including Radon.

Well Water

Radon can also be found in groundwater from private or small community wells. Radon produced in the ground can dissolve and accumulate in water from underground sources such as wells. When water containing Radon is agitated during daily household use – showering, clothes washing or cooking, for example – the Radon gas can be released into the air. However, research has shown that drinking water that contains Radon is far less harmful than breathing the gas. The health risk does not come from consuming the Radon, but from inhaling the gas. And in most cases, the risk of Radon entering the home through water is much lower than if it enters through the ground.

Building Materials

Materials used to construct a house – stones, bricks, cement, or granite, for example – are not a significant source of Radon in Canada. Natural materials taken from the ground, like granite, can contain some uranium and may have higher levels of radiation or Radon than expected, but in the vast majority of cases these levels are not significant. All homes have Radon. The levels can vary dramatically even between similar homes located next to each other. The amount of Radon in a home will depend on many factors. Testing is the only way to know you levels.