In the United States, 15,000 – 22,000 people die from radon-related lung cancer every year (compared to 160,000 lung cancer deaths from smoking).
How are people exposed to Radon?
Normal decay of the elements uranium, thorium and radium found in rocks and soil causes radioactive gas, Radon, to be released into the air. Radon is an invisible, odorless, tasteless gas that seeps up through the ground and diffuses into the air. In a few areas, depending on local geology, radon dissolves into groundwater and can be released into the air when the water is used. Radon gas usually exists at very low levels outdoors. However, in areas without adequate ventilation, such as underground mines, radon can accumulate to levels that substantially increase the risk of lung cancer.
For those of us to don’t work in a mine, exposure to radon gas can happen in our homes or even the workplace.
Radon can enter your home through:
- Cracks in foundation walls and floors
- Gaps in flooring
- Warm air rising indoors
- Spaces around pipes entering the foundation
- Wind blowing outdoors
- Fireplaces and furnaces
- Open areas inside the walls
- Exterior air vents
- Water — usually well water
- Construction joints — where concrete stops and starts again
Radon is a common problem in homes throughout the country — as many as one in 15 U.S. homes has high levels of radon, according to the EPA. But certain geographic regions are more likely to be affected. In general, the Northeast, southern Appalachia, the Midwest, and northern plains areas tend to have levels over the recommended limit of 4 picocuries per liter (pCi/L) of air, while coastal areas tend to have lower levels. Newer homes may also have higher levels of radon due to better porosity in soil around the house, which can make it easier for radon gas to flow in.
But elevated levels of radon can be found in any state and in any home. Often, next-door neighbors can have vastly different radon readings — one safe and the other not.
Typically, we are exposed to radon through the air we breathe and the water we drink. Radon that exists in the ground, groundwater and some natural building materials enters living and work spaces and causes exposure. Although high concentrations of radon in groundwater may contribute to radon exposure through ingestion, the inhalation of radon released from water is usually more important.
In comparison with levels in outdoor air, people who work in confined air spaces, such as mines and below-grade areas of buildings, are exposed to elevated concentrations of radon. Exhalation of radon from ordinary rock and soils and from radon-rich water can cause significant radon concentrations in tunnels, power stations, caves, public baths, and spas. The average radon concentrations in houses are generally much lower than the average radon concentrations in underground ore mines.
How do you know if you are at risk of exposure?
Since you cannot see or smell radon, special equipment is needed to detect it. Testing is the only way to know if a person’s home has elevated radon levels.Indoor radon levels are affected by the soil composition under and around the house, and the ease with which radon enters the house. Homes that are next door to each other can have different indoor radon levels, making a neighbor’s test result a poor predictor of radon risk. In addition, rain or snow, barometric pressure, and other influences can cause radon levels to vary from month to month or day to day, which is why both short- and long-term tests are available.
Short-term detectors measure radon levels for 2 days to 90 days, depending on the device. Long-term tests determine the average concentration for more than 90 days. Because radon levels can vary from day to day and month to month, a long-term test is a better indicator of the average radon level. Both tests are relatively easy to use and inexpensive.
When you’re ready to test your home, contact your state radon office for information on locating qualified test kits or qualified radon testers.
While it is not required by law in NC that radon testers and mitigators have any certifications, the NC Radon Program highly recommends hiring a trained professional.The NC Radon Program cannot endorse any particular certification company or individual, so they recommend researching the individual’s qualifications and asking for references.
Below are links to the three organizations that provide radon testing certifications.
▪National Radon Proficiency Program
▪National Radon Safety Board
You also can order do-it-yourself test kits and obtain information at https://sosradon.org/.
The U.S. Environmental Protection Agency (EPA) recommends taking action to reduce radon in homes that have a radon level at or above 4 picocuries per liter (pCi/L) of air. About 1 in 15 U.S. homes is estimated to have radon levels at or above this EPA action level. Scientists estimate that lung cancer deaths could be reduced by 2 to 4 percent, or about 5,000 deaths, by lowering radon levels in homes exceeding the EPA’s action level.