It is very important to know that radon has adverse health effects. Being a radioactive gas, it is one of the leading causes of lung cancer in non-smokers. Therefore, it is recommended to inquire about this issue before buying or selling a property. Real estate brokers can help you throughout this process.
Is radon present throughout Quebec?
The answer is YES. The difference is that the amount will vary from one region to another, and even from one property to another. It is therefore important to check with a professional in order to learn more about your property.
How can we determine the percentage of radon within a property?
You can purchase over-the-counter screening tests, dosimeters, that cost approximately $45. Otherwise, it is suggested to seek out the help of a professional who can carry out the necessary tests and determine whether it is necessary or not to take action, especially if the concentration is greater than 200 Bq/m3. Then, depending on the outcome, a radon mitigation system may be installed to reduce the percentage of radioactivity in the property.
What type of professional do we need to contact for the evaluation?
For the answers to your questions, you will need to hire a specialist accredited by the C-NRPP (Canadian National Radon Proficiency Program).
Should the presence of radon be reported when selling a home?
When the seller is aware that radon is present or that the radon concentration is greater than 200 Bq/m3 and fails to declare it, “their omission could be judged by a court to have been made with the aim of misleading the buyer.” As a precaution  and to protect the health of the occupants, it is recommended to perform a test before the purchase of a property. As such, your broker will be able to assist you by writing a condition for the promise to purchase.
If the seller tells the buyers that they have had work done to control this situation, the seller could request a copy of the supporting documents (such as the test results and invoices for the work).