Canada's radon guideline is not a law. What statutes, codes, tenancy and workplace rules do require about radon, and how eight peer countries compare.
Photo: Jessica Losorata, CC BY-SA 4.0, cropped, via Wikimedia Commons.
No law requires a test
No Canadian law requires an ordinary existing home to be tested for radon, or fixed when it tests above 200 Bq/m³. The guideline is health advice, and provinces and territories hold the main legal powers.
Canada’s 200 Bq/m³ radon guideline is a federal health recommendation, not a law. No Canadian law makes you test an ordinary existing home, and none makes you fix it above 200 Bq/m³. Legal duties about radon come from building codes, tenancy law, workplace rules and disclosure in a sale. Provinces and territories hold most of those powers, so the rules differ from one province to the next. See every radon rule by province, cited and dated.
The 200 Bq/m³ guideline is a federal health guideline. It is not a general legal limit for homes. We keep four terms apart:
Building codes cover new construction only. The National Building Code added a rough-in in 2010. British Columbia requires a rough-in province-wide for permits from 8 March 2024. Ontario’s code, in force from 1 January 2025, requires one in new houses.
Quebec moved its code threshold from 800 to 200 Bq/m³ in 2021. A rough-in is not a working system, and meeting the code does not guarantee a level below 200 Bq/m³. See what a new home’s code requires.
British Columbia’s building code branch says the code no longer applies once a house is complete and occupied. No Canadian law requires you to test an ordinary existing home, or to fix a level above 200 Bq/m³. A high test result shows that elevated radon exists. It does not, by itself, show who caused it, who knew, who had a duty, whether that duty was breached or what remedy applies.
No licensing system covers radon testers or mitigators. C-NRPP certification is voluntary, and no province regulates radon professionals. Alberta’s Radon Awareness and Testing Act (SA 2017, c R-2.5) received royal assent but has never been proclaimed. No Canada-wide law requires testing in schools or child care. See how to test your own home.
Every province and territory has tenancy law that requires rental housing to be habitable and in good repair. Tenancy tribunals in Ontario and Quebec have held that radon above the guideline breached that duty in the cases before them. The Ontario decision is CET-67599-17 (Re), from 2017, and there are four decisions in Quebec.
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tribunal decisionsDecisions from Ontario and Quebec tenancy tribunals, listed by Health Canada, that found radon above the guideline breached the landlord's duty to keep the unit in good repair in the cases before them. One is from Ontario and four are from Quebec.
No radon-specific statute requires rental homes to be tested. Health Canada notes that occupiers’ liability law also protects tenants. See what tenants and landlords can do.
Federally regulated workplaces have a legal radon limit. Under section 10.26(4) of the Canada Occupational Health and Safety Regulations, the limit is an annual average of 800 Bq/m³. SOR/2026-10 lowers it to 200 Bq/m³ on 30 January 2027.
800
Bq/m³Annual average radon limit for employees other than nuclear energy workers in federally regulated workplaces, under the Canada Occupational Health and Safety Regulations, s. 10.26(4). SOR/2026-10 lowers it to 200 Bq/m³ on 30 January 2027.
This limit applies to workplaces under federal rules. Most other workplaces fall under provincial and territorial powers. No law sets a general radon limit for an existing home. There, the 200 Bq/m³ guideline is advice. See the limits and duties at work.
Responsibility can arise through these routes:
A radon matter may land in a court, a tenancy tribunal, a regulator, a warranty provider or a workers’ compensation system. Health Canada says a local government that decides to inspect owes a common law duty of care, and that courts have found cities liable for missed flaws. How far that duty reaches varies by province.
In a sale, radon comes in through a seller’s duty to disclose a latent defect, a seller disclosure form or a new home warranty. No province requires a test before a resale closes. Real estate agents are licensed, and four regulators have set radon duties for them. They are the BC Financial Services Authority (BCFSA), the Real Estate Council of Alberta (RECA), the Nova Scotia Real Estate Commission, and OACIQ, Quebec’s real estate regulator. See disclosure and holdbacks in a sale.
Here is how the WHO, the European Union and eight peer countries set radon levels. Every level is in Bq/m³.
In Canada, the 200 Bq/m³ guideline is advice for homes, and the federal workplace limit is set in regulation. See what the 200 Bq/m³ guideline means.