What to do about radon in your home?

What is this home-invasive gas and how does it affect our health?

Learn more about radon, how to detect it and what you can do to reduce its concentration in your home.

What is radon?

Radon, a radioactive gas, is created when uranium in soil, rock and groundwater decays.

Outdoors, it dissipates into the air and is generally not a problem.

Indoors however, because of poorer ventilation, most often in the basement, it can pose a health risk to residents.

Radon and Health

Since it’s a gas, it is easily breathed in. And because it’s radioactive, it increases the risk of lung cancer.

In terms of causes of this illness, radon is second only to smoking. In Canada, an estimated 10-16% of lung cancer deaths are attributed to radon.

Non-smokers are not immune. For them, radon is the number one killer.

The three factors that increase the risk of lung cancer from radon are:

• Concentration
• Exposure
• Smoking

Although linked to lung cancer, radon has no effect on:

• Allergies
• Asthma
• Chronic bronchitis
• Emphysema
• Birth defects

Is your home at risk?

Radon is present in every home, it’s the concentration that will vary, even inside a given neighbourhood.

This depends on how the gas is able to seep into the home:

• Concrete slab
• Foundation
• Drainage pipes
• Crawl space
• Catch basin
• Faucets
• Dirt floor
• etc.

According to Health Canada, one in 10 homes has a higher than recommended concentration.

In Quebec, these regions are more at risk:

• Gaspésie-îles-de-la-Madeleine
• Bas-St-Laurent
• Outaouais
• Laurentides

The only way to know how much radon is in your home is through detection.

Detecting Residential Radon

Since radon is odorless, tasteless and colourless, a dosimeter is needed to detect it.

Dosimeters are sold in hardware stores and by radon test kit providers, like Association pulmonaire du Québec.

To adequately measure concentration, tests must be performed under the following conditions:

• Three consecutive months in the winter
• In the lowest section of your home where you spend more than four hours a day (e.g. a home office in the basement)
• Following the test manufacturer’s specifications

You can also call a licensed radon detection company that is certified by the federal and provincial governments.

When is radon concentration considered a cause for concern?

According to Health Canada, remedial action is required when radon concentration is over 200 becquerels per cubic metre (200 Bq/m3).

However, the World Health Organization indicates 100 Bq/m3.

Remedial Action Against Radon

When radon concentrations are between 200 and 600 Bq/m3, Health Canada recommends taking steps to reduce levels within two years.

When concentrations are above 600 Bq/m3, steps to reduce levels within one year should be taken.

This means installing a full active soil depressurization (ASD) system under the concrete slab. Thanks to plumbing and ventilation, the gas will be removed from the home. If the home has a sump pump, it must be sealed to ensure system efficiency.

Have the work done by a qualified radon professional. ASD systems are the most effective at reducing concentrations to below 100 Bq/m3.

Can’t I just open the windows? Unfortunately, leaving your windows open is not enough to reduce radon levels. You would also need a negative pressure system to bring radon down to acceptable concentrations.

Regular testing

Once the work is done, radon levels must continue to be measured every three years.

New Constructions

In Quebec, the Régie du bâtiment du Québec modified its building codes to prevent radon ingress in new homes.

Construction companies have until summer 2023 to comply.

As soon as you break ground on your new construction, make sure the contractor installs a rough-in for a radon mitigation system with a sealed membrane under the concrete slab. A passive vertical radon stack is another option when radon levels must be reduced.

Protecting What’s Most Important

Your and your loved ones’ health is priceless. This is why a radon test kit is a worthwhile investment.

Plus, actively mitigating residential radon levels will preserve your home’s value.