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Healthy living environment

Radon is a radioactive gas that comes from uranium naturally present in the earth's crust. Radon is found in the ground, all over the Earth's surface. The amount of radon in the ground can vary significantly from place to place. Radon can also be found in groundwater.

Radon can seep into buildings, especially through the foundations. It can sometimes accumulate and reach concentrations that can pose a health risk. As it is a gas that has no smell, taste or color, it is impossible to detect it by the senses.

Health effects

Radon enters the lungs with the air we breathe. Major organizations and international health agencies have recognized radon as a carcinogen. It emits radioactive radiation which can, in the long term, cause lung cancer.

Radon is the second leading cause of lung cancer, after smoking. It is also the leading cause of cancer in non-smokers. In Quebec, 10 to 16% of lung cancer deaths are associated with radon. This is more than 1000 deaths per year. Among these deaths:

  • 60% occur in smokers;
  • 30% among former smokers;
  • 10% among non-smokers.

The risk of radon-related lung cancer increases with:

  • radon concentration: the more a person is exposed to a high concentration of radon, the greater their risk of cancer;
  • the duration of exposure to radon: the risk of cancer increases for a person who is exposed to radon for several decades;
  • smoking: smokers exposed to radon have a higher risk of developing lung cancer than non-smokers.

Radon does not cause :

  • respiratory disorders, such as chronic bronchitis and emphysema;
  • allergies;
  • asthma;
  • congenital malformations.

Identify radon sources in a building

Radon levels are generally very low outdoors. Radon is quickly diluted in ambient air and therefore does not cause health problems.

However, radon can infiltrate the indoor air of buildings through various openings:

  • dirt floors;
  • cracks in the concrete slab or foundation walls;
  • sumps;
  • crawl spaces;
  • joints;
  • openings around exhaust ducts and service entrances, for example pipe fittings;
  • faucets, especially the shower one. Faucets can be an entry route for radon from radon-rich groundwater. They can thus contribute to increasing the concentration of radon in the indoor air of a house.

Source : Natural Resources Canada

Radon mainly accumulates in the lowest and least ventilated rooms of a building, for example the basement. The radon concentration in the indoor air of a home can depend on several factors:

  • the concentration of uranium and radon in the soil;
  • the climate;
  • the ventilation of the premises;
  • waterproofing and insulation of the house;
  • negative pressure, ie the fact that the air pressure is less inside the building than outside. This pressure difference has the effect of transforming the dwelling into a sort of vacuum cleaner. Radon can then seep through cracks and other entry points that are in contact with the ground

The only way to know if there is radon in a home is to measure it.

Measure the radon concentration in a residence

To find out the radon concentration in your home, it must be measured using a measuring device called a dosimeter. It is advisable to do this measurement for a period at least 3 months and to measure radon during the winter. You can measure the radon concentration in your home yourself or use the services of a professional.

Do not rely on the results of tests carried out in a house next to yours or in other houses in your neighborhood. Indeed, the radon concentration can vary a lot from one house to another, even if they are very close to each other.

To measure the radon concentration in your home yourself, you must obtain a dosimeter and use it according to the manufacturer's instructions. For an Alpha type dosimeter you will have to pay around $45 for the purchase and $10 to $20 for shipping to a certified laboratory. A total of about $65 and you have to wait 5 to 6 weeks for the results . Gaz radon Québec offers an option for quick recovery of results thanks to a device with an ionization chamber and an electret. The result will be known the day after the delivery of the detector to our laboratory . Gaz Radon Quebec offers you for the modest sum of $100 including handling fees.

To obtain an Alpha type dosimeter, you can:

  • order it on the Quebec Lung Association website, which offers dosimeters certified and approved by Health Canada;
  • consult the website of CAA Québec Habitation , which provides information on how to obtain a dosimeter;
  • get a radon analysis kit in the air at some hardware stores.

To obtain a list of professionals certified in radon measurement in Quebec, you can use the search tool of the National Radon Competency Program in Canada (NRCP-C). This certification program is recognized by Health Canada and the Quebec Ministry of Health and Social Services.

What to do if Radon Concentration Exceeds Canadian Guideline

Radon is measured in becquerels per cubic meter of air (Bq/m³).

There is a guideline in Canada indicating that the radon concentration not to be exceeded in a home is 200 Bq/m³. In general, the concentration of radon is not very high in homes in Quebec. The average radon concentration in basements is around 35 Bq/m³. However, the concentrations can sometimes reach very high levels, up to more than 1,000 Bq/m³.

Individual protection measure

If you smoke, the first thing to do to protect yourself against radon lung cancer is to quit smoking . It is the fastest and cheapest way to reduce the risk of lung cancer associated with radon. Indeed, a person who is exposed to both tobacco smoke and radon gas greatly increases this risk.

Corrective measures for your residence

Health Canada recommends taking corrective measures when the average annual radon concentration exceeds 200 Bq/m³ in occupied spaces of a dwelling. If this is the case in your home, then you need to take action whether you are a smoker or not.

The recommended time frame for corrective action depends on the average radon concentration in your home:

  • if the concentration exceeds 600 Bq/m³, you should take corrective action within less than a year;
  • if the concentration is between 200 Bq/m³ and 600 Bq/m³, you should take corrective action within 2 years.

You will get better results by applying more than one corrective measure. For example, you can:

  • seal the cracks in the foundation;
  • sealing openings in contact with the ground;
  • ensure sumps are covered and vented to the outside;
  • improve the ventilation of your home, especially in the basement.

If radon levels in the home are very high, these measures may not be enough, as they do not completely prevent radon infiltration. In this case, call in a qualified contractor. The contractor will install a system to evacuate the radon present under the foundations before it enters the living spaces of the building.

Health Canada recommends that people taking corrective action try to reduce radon levels to the lowest level possible. This is why it is recommended to measure the radon concentration again after applying corrective methods, in order to check their effectiveness.

Several specialized companies can help you reduce the concentration and infiltration of radon in your home. It is very important to do business with a certified company. You can consult the list of these companies on the website of the National Radon Competency Program in Canada (NRCP-C) from Health Canada. Gaz Radon Québec is a certified company.

Measures for new constructions

When building a new home, you can ask your contractor to install the infrastructure needed to implement radon mitigation measures in the home at a low cost. Perform a radon test as soon as possible. If mitigation measures should be necessary, the infrastructure in place greatly facilitates and simplifies the work and reduces the costs associated with such work. Again, Gaz Radon Québec can help you implement appropriate mitigation measures for your building.

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