Radon mitigation programs support systems and technologies designed to prevent radon from entering occupied buildings and lowering existing indoor air radon levels. Radon mitigation systems can include subslab depressurization (SSD), which depressurizes soil using a vent pipe system and a fan; sealing cracks and openings in building foundations; home or room pressurization; heat recovery ventilation; or natural ventilation (US EPA-Radon). Radon is a radioactive, odorless, tasteless, and colorless gas which occurs naturally in the environment. When radon escapes from soil and rocks, it creates compounds that are hazardous to health, particularly for smokers; radon is the second leading cause of lung cancer (Kim 2016a).
Expected Beneficial Outcomes (Rated)
Reduced radon exposure
Improved health outcomes
Evidence of Effectiveness
There is some evidence that radon mitigation programs reduce exposure to radon (Brossard 2015*, Boardman 2015*, Lutes 2015, Lantz 2013*, Sethi 2012*, Sandel 2010*, NCHH-Jacobs 2009, Steck 2012*) and reduce the likelihood of developing lung cancer (Lantz 2013*, Sethi 2012*, Sandel 2010*, NCHH-Jacobs 2009, Steck 2012*). Evidence is strongest for active soil depressurization systems, also called subslab depressurization (SSD) (Brossard 2015*, Lutes 2015, Boardman 2015*, Sandel 2010*, NCHH-Jacobs 2009, Steck 2012*, Sethi 2012*). Additional evidence is needed to confirm effects of interventions such as passive air, room pressurization, and heat recovery ventilation (NCHH-Jacobs 2009, US EPA-Radon).
Radon mitigation programs can have the greatest health benefits and be most cost effective when targeted at smokers or other high-risk populations (Lantz 2013*). The effectiveness of each measure varies based on individual building characteristics (Sethi 2012*). A Canada-based study suggests that above ground level discharge (AGL), a form of soil depressurization, is more cost effective and better suited for cold climates when fans are placed in basements than in attics (Brossard 2015*). Radon mitigation programs may effectively reduce exposure to alpha radiation emissions if such programs include efforts to reduce exposure to some of the 39 radon isotopes and isomers that are also alpha emitters. For example, Radon-220, also known as thoron, is a radon isotope and an alpha emitter; filtration techniques can reduce the concentration and inhalation dose of thoron decay products (Chemistry-Rn, Wang 2011*).
Mitigation is often undertaken by individual property owners or tenants. The cost of mitigation and a lack of concern over elevated radon levels are often reasons individuals decide against mitigation. Concern over real estate values, living in a home less than 10 years old, and possession of a college education are associated with the choice to mitigate (Riesenfeld 2007*).
Researchers suggest that partnerships between health care providers, public health agencies, and environmental organizations may help increase awareness of the existence and dangers of radon, encourage testing of homes for radon, and support mitigation efforts (Larsson 2014, Bain 2016, Levy 2015a). Experts suggest establishing a federally mandated maximum radon limit for schools and public buildings, along with guidelines and timelines for testing, mitigation, and retesting (Gordon 2018).
Impact on Disparities
Most states’ Departments of Health have a radon protection program. The US Environmental Protection Agency (EPA) provides information on state and local radon programs and contacts, along with a map of radon zones (US EPA-Radon contacts).
As of December 2016, 18 states have radon mitigation laws in place (LawAtlas-Radon).
US EPA-Radon reduction 2016 - US Environmental Protection Agency (US EPA). Consumer’s guide to radon reduction: How to fix your home. 2016.
US EPA-Radon federal action plan - US Environmental Protection Agency (US EPA), US Department of Health and Human Services (US DHHS), US Department of Agriculture (USDA). Federal radon action plan.
PHLR-Radon - Center for Public Health Law Research (PHLR). Video: Mandatory testing of radon levels in for-sale homes. Critical Opportunities Initiative of the Robert Wood Johnson Foundation, 2012.
Radon mitigation-KS - Kansas State University. National Radon Program Services: Radon mitigation. In collaboration with the US Environmental Protection Agency (US EPA).
Citations - Evidence
* Journal subscription may be required for access.
Brossard 2015* - Brossard M, Ottawa CB, Falcomer R, Whyte J. Radon mitigation in cold climates at Kitigan Zibi Anishinabeg. Health Physics. 2015;108(Suppl 1):S13-S18.
Boardman 2015* - Boardman CR, Glass S V. Basement radon entry and stack driven moisture infiltration reduced by active soil depressurization. Building and Environment. 2015;85:220-232.
Lutes 2015 - Lutes CC, Truesdale RS, Cosky BW, Zimmerman JH, Schumacher BA. Comparing vapor intrusion mitigation system performance for VOCs and radon. Remediation Journal. 2015;25(4):7-26.
Lantz 2013* - Lantz PM, Mendez D, Philbert MA. Radon, smoking, and lung cancer: The need to refocus radon control policy. American Journal of Public Health. 2013;103(3):443–7.
Sethi 2012* - Sethi TK, El-Ghamry MN, Kloecker GH. Radon and lung cancer. Clinical Advances in Hematology & Oncology. 2012;10(3):157–64.
Sandel 2010* - Sandel M, Baeder A, Bradman A, et al. Housing interventions and control of health-related chemical agents: A review of the evidence. Journal of Public Health Management and Practice. 2010;16(5 Suppl):S24-33.
NCHH-Jacobs 2009 - Jacobs DE, Baeder A. Housing interventions and health: A review of the evidence. Columbia: National Center for Healthy Housing (NCHH); 2009.
Steck 2012* - Steck DJ. The effectiveness of mitigation for reducing radon risk in single-family Minnesota homes. Health physics. 2012;103(3):241–8.
US EPA-Radon - US Environmental Protection Agency (US EPA). Radon.
Chemistry-Rn - Chemistry-Reference.com. Radon (Rn).
Wang 2011* - Wang J, Meisenberg O, Chen Y, Karg E, Tschiersch J. Mitigation of radon and thoron decay products by filtration. Science of the Total Environment. 2011;409(19):3613-3619.
Riesenfeld 2007* - Riesenfeld EP, Marcy TW, Reinier K, et al. Radon awareness and mitigation in Vermont: A public health survey. Health Physics. 2007;92(5):425-31.
Larsson 2014 - Larsson LS. Risk-reduction strategies to expand radon care planning with vulnerable groups. Public Health Nursing. 2014;31(6):526-536.
Bain 2016 - Bain AA, Abbott AL, Miller LL. Successes and challenges in implementation of radon control activities in Iowa, 2010–2015. Preventing Chronic Disease. 2016;13:150596.
Levy 2015a - Levy BT, Wolff CK, Niles P, et al. Radon testing: Community engagement by a rural family medicine office. The Journal of the American Board of Family Medicine. 2015;28(5):617-623.
Gordon 2018 - Gordon K, Terry PD, Liu X, et al. Radon in schools: A brief review of state laws and regulations in the United States. International Journal of Environmental Research and Public Health. 2018;15(10):2149.
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