About Radon

Radon is a radioactive gas released from the decay of naturally-occurring uranium and thorium in rocks and soil. It can collect in confined areas or underground spaces where ventilation is poor.

Exposure to radon causes lung cancer. Smokers who are exposed to radon have a greatly increased risk of lung cancer [1]. CAREX Canada estimates that approximately 188,000 Canadians are exposed to radon at work [2].

Burden of Cancer Results

Results from the Burden of Occupational Cancer study show that approximately 190 lung cancers are attributed to occupational radon exposure each year, based on 2011 cancer statistics. This amounts to 0.8% of all lung cancers diagnosed annually in Canada. The cost of newly diagnosed radon-related lung cancer cases is $185 million annually.

The industries with the largest burden of radon-related cancers are finance, insurance, real estate and leasing; trade; government services; mining and oil and gas extraction; educational services; and manufacturing.

Exposure Reduction

Canada’s Naturally Occurring Radioactive Materials (NORM) Guidelines recommend reducing radon levels to less than 200 Bq/m3 for incidentally exposed workers, and provides other recommendations for those working directly with radioactive materials. However, these guidelines are not legally enforceable. Developing enforceable regulation for radon in indoor air that is consistent with the NORM guidelines is an important step to reduce exposure. This includes adopting an exposure standard for remediation of 200 Bq/min all workplaces, and implementing regular exposure monitoring.

Burden Fact Sheets

Related OCRC Research

OCRC Projects

Research Articles


  1. International Agency for Research in Cancer. IARC Monographs Vol 100D: Radiation (2012).
  2. CAREX Canada. Radon Occupational Exposures Profile.