Government of Canada Radon Action Guideline
Remedial measures should be undertaken in a dwelling whenever the average annual radon concentration exceeds 200 Bq/m3 in the normal occupancy area.
The higher the radon concentration, the sooner remedial measures should be undertaken.
When remedial action is taken, the radon level should be reduced to a value as low as practicable.
The construction of new dwellings should employ techniques that will minimize radon entry and facilitate post-mitigation radon removal should this subsequently prove necessary.
NO REGULATION GOVERNS WHAT IS AN ACCEPTABLE EXPOSURE. CONCENTRATIONS AS LOW AS 100 Bq/m3 CAN INCREASE YOUR RISK OF DEVELOPING LUNG CANCER
World Regulatory Radon Guidelines
Organization Residential (Bq/m3)
Health Canada 200
World Health Organization 100
International Commission on Radiological Protection 300
United States Environmental Protection Agency 150
European Union 200