Printer Friendly, PDF & Email

Radon is a colourless, odourless gas that is released during the naturally-occurring, radioactive decay of uranium in rocks and soils. Radon levels outdoors are generally low; however, radon can enter buildings through cracks and openings in the foundation and levels can become much higher indoors, especially in basements and lower floors. Exposure to radon over time increases the risk of developing lung cancer. Health Canada estimates that over 3,200 Canadians die each year due to radon gas exposure (Chen et al., 2012). Smoking places people at higher risk from radon exposure, increasing the odds of developing lung cancer from 1 in 20 to 1 in 3 (Health Canada, 2010).

Radon levels are influenced by such factors as:

  • geography (which determines the amount of uranium and radon in soil)
  • household construction methods and architectural design
  • natural ventilation and ventilation systems, and
  • the specific materials used to build a home

Because of these multiple inter-related factors, it is impossible to predict levels of radon without measuring them. Health Canada recommends that all Canadians have their homes tested for radon (Health Canada, 2013). The Government of Canada’s recommended guideline for homes and public spaces including schools, daycare and libraries, is 200 becquerels per meters cubed (Bq/m3) (Government of Canada, 2009) whereas the World Health Organization recommends 100 Bq/m3 (WHO, 2016).

If a building exceeds the federal guideline, Health Canada recommends that measures be taken to reduce those levels. Radon mitigation systems installed by certified professionals are very effective at reducing radon levels even when results far exceed the recommended guideline. A list of certified professionals is available at the Canadian National Radon Proficiency Program.

NCCEH Resources

  • Inuit and Metis radon research across the country (NCCEH, 2018)
    Two presentations provide an historical overview of radon testing conducted in First Nations, Inuit and Metis communities across Canada.  Resources uncovered include a 1993 federal testing program of homes as well as a more recent federal program that included testing in administration buildings, schools and other public spaces in first nations communities.
  • Radon and child care facilities (NCCEH, 2017)
    This presentation was made at the Canadian Institute of Public Health Inspectors National Annual Education conference by NCCEH staff in conjunction with an environmental health officer from the British Columbia Interior Health Authority.
  • Call for action on radon in childcare settings (Phipps et al, 2017)
    This article from Environmental Health Review is co-authored by NCCEH staff and outlines the rationale for implementing regulations to govern the testing of radon in child-care settings across Canada.
  • Public health ethics: A case for environmental health (NCCHPP, 2016)
    The National Collaborating Centre for Health Public Policy, in conjunction with the NCCEH and the INSPQ, hosted a webinar to discuss the ethical dimensions involved in testing for radon in childcare facilities.
  • Radon: Public health professionals can make a difference (Nicol et al, 2015)
    This NCCEH article published in the Environmental Health Review is aimed at providing information on radon risks and mitigation to public health inspectors.
  • Radon and lung cancer (NCCEH, 2015)
    Invited presentations to the House of Commons Standing Committee on Health (HESA) by NCCEH staff regarding radon and the risk of lung cancer.

Other Selected Resources

  • Take Action on Radon (2019) 
    This Health Canada funded program provides quick links to information and resources for radon testing and mitigation across the country. Take Action on Radon offers the “100 Test Kit Challenge” program which supports community access to free radon test kits as well as education and outreach.
  • Radon: Quick summary (CAREX Canada, 2019)
    This webpage includes resources on evidence, policies and guidelines pertaining to environmental and occupational radon exposure in Canada. It also links to summaries on radon testing initiatives in schools across the country.
  • Reducing the risk from radon: A guide for health care providers (Conference of Radiation Control Program Directors, 2018)
    This guide, developed in conjunction with the US EPA, is targeted to health care providers. This guide was designed to help health care providers inform patients about exposures to radon. This guide has the latest information on the science behind the risk estimates, sample guidance for use in health care settings and the role of health care providers in reducing the burden of radon.
  • Environmental Scan of Radon Law and Policy: Best Practices in Canada and the European Union (Canadian Environmental Law Association, 2018).
    This report is an analysis of existing radon policy initiatives at the domestic and international level. Recommendations are made to strengthen specific regulations to reduce radon exposure.
  • Radon - online course for physicians (McMaster University, 2017)
    This Continuing Medical Education (CME) course for physicians is offered through McMaster University. This program is designed to help answer patient's questions about the health risks of radon and the need to test their home and reduce their family’s exposure.
  • Environmental burden of cancer in Ontario (Public Health Ontario, 2017)
    This useful report estimates that radon contributes to between 1,080 to 1,550 new cases of cancer every year in Ontario alone. For more information and an explanation of how this estimate was calculated, see the report and its technical supplement.

Peer-Reviewed Literature

This list is not intended to be exhaustive. Omission of a resource does not preclude it from having value.

Last updated Nov 20, 2019