January was Radon Action Month, which put a spotlight on the health risks posed by elevated concentrations of radon in indoor air. Radon is a naturally occurring radioactive gas that is produced as the uranium which is present in soil, rock and water breaks down. As a recognized carcinogenic, the EPA estimates that exposure to radon gas is responsible for more than 20,000 lung cancer deaths a year.
Radon can enter our living spaces at any time in the year – for example through cracks in floors and walls, gaps around service pipes or through construction joints – and indoor air quality should therefore be tested regularly to ensure that indoor radon concentrations are below recommended levels. But, indoor radon levels tend to be highest in the winter months (followed by summer, with levels lowest in spring and fall), which means now is a good time to revisit radon risks at your property.
Why Cold Weather Exacerbates Radon Risks
As the cold winter weather begins to sweep the country, people are bundling up, closing their windows and doors, and spending more time indoors. As everyone seals up their homes and offices, ventilation is reduced and radon that may otherwise dissipate can be trapped to accumulate within the indoor space, creating significant health risks to occupants.
Additionally, the rate at which radon is drawn into indoor spaces increases in the winter. This is because the temperature ratio from the outside to inside affects the movement of air into and out of buildings, known as “stack effect”. Air pressure inside your home is usually lower than the pressure in the soil around your home’s foundation. During the winter, stack effect tends to be greater as the warm heated air (less dense) within the house rises and escapes to the colder air outside. As air escapes, the house has to replace the air to equalize pressure. The flow of air leaving the top of the building draws cold air in through the bottom. New air can come from the soil the house is built upon. Because of this difference in pressure, your house acts like a vacuum drawing in air through foundation cracks, plumbing pipe penetrations, sump pump pits, floor drains, crawlspaces and any other areas that have contact with the soil. This new air that enters can contain radon gas.
The timing of Radon Action Month is opportune, because not only are indoor radon gas concentrations likely to be higher during this season, it is also more easily detected in a closed environment. And, testing in winter can make things easier for radon field assessors too. One of the biggest challenges I encounter during multi-family testing is to ensure the “closed-house conditions” required for short-term radon tests. Tenants are much more likely to comply with the request to keep windows and doors closed for 12 hours prior to and during the testing in winter months than at other times of the year!
Radon Action Month – Addressing Radon Risks
In recent years, dozens of new state radon legislation have been filed in state legislatures to address radon concerns and protect occupants’ health. Increased radon awareness coupled with the support of legislation has had a big impact: radon testing and mitigation efforts have increased significantly in recent years. For example, when Illinois passed the Radon Awareness Act in 2007 demand for radon testing increasing by 300%. More recently in 2013, Minnesota saw a 400% increase in mitigation with a new radon awareness policy.
For property owners and managers, Radon Action Month is the perfect time to reconsider radon concerns. Radon assessments can be done easily and inexpensively, and many effective solutions are available to reduce radon levels to safe levels to protect occupants from health impacts, and protect themselves from regulatory action or ligation risks!