Radon action guide for municipalities: Overview

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Radon is a naturally occurring radioactive gas that emanates from the ground and can enter and accumulate in buildings. Radon gas is found in every building in Canada at some level. Radon exposure is the leading cause of lung cancer after smoking, and accounts for an estimated 16% of lung cancer deaths in Canada. Radon risk reduction is easy to address through testing and mitigation. Simple tests involve placing a long-term radon detector in the lowest lived-in level of a building for 3 months during the fall-winter months. Health Canada estimates that about 7% of homes will have a high radon level. This percentage varies significantly across Canada, as shown by Health Canada's radon map. There are relatively inexpensive and very effective ways to reduce radon exposure in homes and buildings with high radon levels, that is, over the Canadian radon guideline of 200 Bq/m3.

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Organization: Health Canada

Published: October 2022

Municipalities can become leaders in advancing radon action through:

This action guide describes:

Review companion documents to this one when coming up with your strategy, including:

Learn more about:

About radon in Canada

Radon is a naturally occurring radioactive gas found in every building in Canada. Radon gas comes from the breakdown of uranium in the ground. Long-term exposure to high radon levels is the leading cause of lung cancer after smoking, and accounts for more than 3,000 lung cancer deaths in Canada. The Canadian guideline for radon is set at 200 Bq/m3. Remedial measures should be undertaken whenever the average annual radon concentration exceeds the Canadian guideline in normally occupied areas of buildings. Across Canada an average of 7% of homes have radon concentrations that exceed the guideline. Radon levels in buildings vary significantly by geography and building characteristics. Surveys have found that in parts of New Brunswick and Manitoba over 40% of homes tested were above the Canadian guideline and some cities, such as Castlegar, British Columbia and Regina, Saskatchewan, show over half of homes above the guideline.Reference 1 Public awareness remains low and a vast majority of homeowners in Canada (>90%) have never tested for radon.

Health Canada has developed guidance on radon testing in homes. Testing ideally involves placing a small detector in the lowest regularly occupied level of the home (basement or main floor) for at least 3 months during the heating season. These do-it-yourself (DIY) long-term test kits are available from a variety of online suppliers and hardware stores. They typically cost $30 to $60. "Real time" digital monitors are also available and can give a short snapshot of radon levels, but should be supplemented with 3-month tests. Radon measurement services from professionals certified by the Canadian National Radon Proficiency Program (C-NRPP) are also available. If test results are high (above 200 Bq/m3), a radon mitigation professional certified by the C-NRPP can determine and implement the most appropriate method to reduce the radon level. Techniques to lower radon levels are effective and can save lives. A radon mitigation system, which can be installed in less than a day, will reduce the radon level by more than 80% in most homes. The cost is about the same as other common home repairs, such as replacing the furnace or air conditioner. While waiting for mitigation, people can also temporarily open windows on the lowest level of the home or run a well-maintained mechanical ventilation system to dilute with fresh air.

Over the last decade, some radon awareness, action and policy progress have been achieved in Canada.

Health Canada's National Radon Program (NRP) has taken a number of steps to ensure radon is taken seriously in Canada. It:

Across Canada, governments and other institutions have:

Despite this progress, there are still many regulatory gaps in Canada, with many people living and working in high radon environments without knowing it.

While public awareness has increased, there is much work still to be done. Local, community-based implementation is needed to ensure progress in reducing radon exposure.

This guide will help municipal governments develop programs and policies to address radon. It considers individual interventions across the built environment such as:

It draws on existing experience of radon action from across Canada, the United States and Europe.

Companion documents to this one should be reviewed, including the following:

Justifications and policy rationales for radon action: Provides detail on why governments should take action, discussing societal values around public health, saving lives and environmental concerns. It also discusses initiatives already in place for which radon action is a natural extension, from disease prevention strategies to healthy community planning.

Radon action guide for provinces and territories: Provides a series of steps that provinces can take to establish a radon action plan. It also discusses in detail the division of powers in Canada, why provincial action is required, and draws from international experience.

Radon action in municipal law: Understanding the legal powers of cities and towns in Canada: Provides a review of the powers that municipalities have to address radon, recognizing that municipalities are "creatures of the provinces" and constrained by enabling law.

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Why municipalities should take action

Governments play a role in helping individuals avoid risks. Health Canada research estimates that with lifetime exposure at 800 Bq/m3, the lifetime lung cancer risk would be 5% (1 in 20) for non-smokers, significantly higher than the baseline lung cancer rate of 1% (1 in 100).Reference 2 People who smoke and also live in high radon environments can have a 1 in 3 chance of contracting lung cancer. Canadians expect health and safety standards for their homes, workplaces, and recreational spaces.

Radon is one of a number of emergent indoor air quality concerns which lead to a focus on indoor environmental health. Radon is thus included in Health Canada's Residential Indoor Air Quality Guidelines. Radon action is a proven and cost-effective way to save lives and is a natural extension of existing policy and planning frameworks that support action on health and environment.

In the companion document, Justifications and Policy Rationales for Radon Action, a variety of reasons why governments should take action on radon are outlined in more detail.

This guide details many action items that municipalities and local government can take, independently or in concert with higher levels of government. Radon fits within a variety of policy platforms municipalities already use, such as:

Learn more about:

Legal powers

Municipalities have legal powers to act on radon. Most provinces' municipal legislation mentions protecting health and safety as part of the general purposes of a municipality or allows for bylaws concerning health.Reference 3 Many provinces also provide that municipalities have the purpose of fostering environmental well-being or can make bylaws to protect the environment.Reference 4 Radon can fit into these powers, and the document Radon Action in Municipal Law sets out specific actions on radon that municipal law frameworks support.

Municipalities can take a leadership role and show that bold action on radon is possible. As the level of government often closest to people, and the one with which they identify, municipalities will often be trusted to respond to citizens' concerns. Even when provinces engage in comprehensive radon planning there will be important roles for municipalities. Municipalities enforce areas which make up core components of radon policy, including:

Risk management

Municipalities are employers, building owners and operators and at times landlords. As such they are subject to many laws that impose general duties to ensure spaces are safeā€”and increasingly these laws are recognized as including protection from elevated radon. Municipalities are also subject to a duty of care when inspecting buildings. As Building Codes are updated to include radon-resistant construction techniques, this creates new responsibilities for municipal building inspectors. Becoming aware of radon and taking steps to address it can be a good way to avoid exposure to litigation.

Increasing value of building stock

Radon action can increase the value of the building stock. Certified mitigators can reduce radon levels to safe levels, which can become a selling feature. This not only assures users and owners that radon has been dealt with, but also increases the value of the home or business.


Reference 1

Stanley, F.K., Irvine, J. L., Jacques, W.R., Salgia, S.R., Innes, D.G., Winquist, B.D., Torr, D., Brenner, D.R. and Goodarzi, A.A., 2019. "Radon exposure is rising steadily within the modern North American residential environment, and is increasingly uniform across seasons," Scientific Reports9(1), pp. 1-17.

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Reference 2

Chen, J., 2017. "Lifetime lung cancer risks associated with indoor radon exposure based on various radon risk models for Canadian population," Radiation Protection Dosimetry 173(1-3), pp. 252-258.

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Reference 3

Community Charter, SBC 2003, c 26, s. 8(3)(i); Municipal Government Act, RSA 2000, c M-26, s. 3(c) and 7(a); Municipalities Act, SS 2005, c M-36.1. 4(2), and s. 8(1)(b); The Cities Act, SS 2002, c C-11.1, 4(2) and (8(1)(b); The Northern Municipalities Act, 2010, SS 2010, c N-5.2 The Northern Municipalities Act, 2010, SS 2010, c N-5.2 s. 4(2) and 8(1)(b); Municipal Act, CCSM c M225 232(1) (a); Municipal Act, 2001, SO 2001, c 25, (s. 10 (1), s. 10 (2)(6), s. 11(1) and 11(2)(6)); Municipal Powers Act, CQLR c C-47.1, s. 4 (5), s. 4(7), s. 55; Local Governance Act, SNB 2017, c 18, s. 10 (1)(a); Municipal Government Act, RSPEI 1988, c M-12.1, s. 180, Municipal Government Act, SNS 1998, c 18 s. 172 (1)(a).

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Reference 4

Community Charter, SBC 2003, c 26, s. 7(d); Municipal Government Act, RSA 2000, c M-26, s. 3(a.1); Municipalities Act, SS 2005, c M-36.1. 4(2)(d); The Cities Act, SS 2002, c C-11.1, 4(2)(d); The Northern Municipalities Act, 2010, SS 2010, c N-5.2 s. 4(2) (d) and 8(1)(b); Municipal Act, 2001, SO 2001, c 25, (s. 10 (2)(5), s. 10 (2)(6), s. 11(2)(5); Municipal Powers Act, CQLR c C-47.1, s. 4 (4), s. 19 Local Governance Act, SNB 2017, c 18, s.5 (d); Municipal Government Act, RSPEI 1988, c M-12.1, s. 180 m), Municipal Government Act, SNS 1998, c 18 s. 172 (1)(a).

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