Radon Gas

Overview of radon gas

Although radon is natural, it can build up inside buildings and become harmful to human health. According to Health Canada, radon is the number one cause of lung cancer in non-smokers.

Dangers of radon gas

Radon gas causes lung cancer. The risk of cancer depends on the levels of radon and amount of contact with radon and tobacco smoke over a lifetime. According to Health Canada, “There is no [radon] level that is considered risk free.”

Radon gas is the leading cause of lung cancer in non-smokers
Radon gas is the second leading cause of lung cancer overall, next to smoking
Smoking significantly increases your risk of lung cancer
Health Canada estimates one in three smokers exposed to high radon levels will develop lung cancer

Diagram showing the risk of inhaling radon gas

Table showcasing how the risk of lung cancer increases with exposure to increasing levels of radon

Radiation from radon gas

Radiation released from radon gas particles can damage DNA which can lead to lung cancer. In general, the higher the radon level and the more time a person is exposed to radon the more damage to lung tissue that occurs. This results in a greater chance of developing the disease. In addition, if a person smokes, or is exposed to environmental tobacco smoke and radon the risk of lung cancer is much higher.

Radon gas in homes and buildings

Radon takes the easiest path into our homes and indoor places. Radon can enter a building through small or large openings in the foundation. The amount of radon entering can be affected by the heating and ventilation system. During the cooler months, windows and doors are often closed and rising warm air in a home draws more radon from the ground.

Check out this illustration of how radon enters a house

Radon will be present in all indoor spaces such as homes, places of work, schools, daycares and public buildings. Indoor areas in contact with or below the ground are more likely to contain higher levels. While any amount of radon puts our health at risk, the longer the contact the greater the risk.

The only way to know the radon levels in your home or other buildings is to test for radon. Just because your neighbours may have low radon levels does not mean the levels in your home are low, too. How each house is constructed can make a big difference and will impact if you have radon in your home.

Testing for radon

Testing is the only way to know the level of radon in your home or building, so be sure to order a radon test kit. Ideally, testing should occur during winter months

There are two types of radon tests: long term and short term. We recommend using long-term tests, as they provide the most accurate picture of what you are breathing. Long-term tests are those in which the radon detector is in place for a minimum three months (91 days). You can get a long-term radon test kit through the links below:

Do-it-Yourself Kits:
- BC Lung Foundation – order online or by calling
- List of other companies with do-it-yourself kits
Find a Measurement Professional

You should re-test after you renovate, make your house more energy efficient, or make changes or additions to your Heating Ventilation Air Condition (HVAC) system that could influence indoor pressures.

See the Resources section below for information on testing homes, schools and large buildings.

Understanding your radon test result

Use your long-term radon test result from your home and/or buildings and check out this table of radon levels in the home to understand your risk of lung cancer from radon. The table highlights the risk of lung cancer per 1,000 people when exposed to different levels of radon gas based on a lifetime (70 years) of exposure.

Note: Health Canada recommends lowering radon levels to as low as reasonably achievable.

Lowering radon levels

Follow the actions listed below to lower radon levels in your home or building. Remember to complete another long-term radon test to know if your fix worked.

Active soil depressurization is the best and most permanent method for reducing radon because it provides an alternate path for the radon gas to travel rather than into the building. The cost can range between $350 and $3,000, depending upon site-specifics.

Check out this illustration of ventilation methods for radon in the home

Immediate, short-term actions to lower radon levels

To take immediate action on radon while you are waiting for construction repairs to be completed:

Limit the amount of time you spend in high radon areas of your home or building. For example, limit the use of the basement
Open windows or adjust HVAC system to increase fresh air flow and allow the radon gas to escape to the outdoors
Make your main bedrooms on above-ground levels
Ensure the lowest floor of your home or building that has people in it for more than four hours per day is tested for radon to know your actual risk

Long-term actions to lower radon levels

To lower the radon levels in a home or building for the long term, arrange for a radon professional or do one or more of the following:

Increase the fresh air flow or pressure by adjusting the HVAC system
Seal basement or crawlspace floors, especially dirt or unfinished floors
Seal cracks and openings in foundation walls and floors, and around pipes and drains
Seal obvious openings in the floor slab, such as sump pits, cracks, and ensure floor drain and unused fixture traps stay filled with water (cover water with vegetable oil to slow evaporation)
Install an active soil depressurization system