According to the current Canadian guideline, the radon concentration should be no greater than 200 becquerels per cubic metre (200 Bq/m^3) for indoor air in dwellings. Radon exposure higher than the guideline presents a health risk. It is up to the home-owner to determine which radon concentration (below the Canadian guidelines, of course) they are willing to accept. Learn more about how you can test for radon in your home.