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Radon is a naturally occurring radioactive gas, produced when uranium breaks down. This gas is released through rocks, soil, and water, and can build up in enclosed spaces through cracks in a building’s foundation or other openings. Because it’s invisible and odorless, radon exposure doesn’t cause immediate symptoms.
However, radon is the second-leading cause of lung cancer, resulting in more than 21,000 deaths every year in the U.S. It is the leading cause of lung cancer for non-smokers.
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The highest concentrations of radon develop in spaces below ground level without much ventilation: basements, crawlspaces, foundations, sump pumps, and construction joints. While pockets of radon can be found across the country, some states have higher levels than others. Check your state’s radon levels here.
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If you live in an older home, or in a state with higher radon levels, be sure to test your home for the presence of radon. Safewise.com recommends these six detectors.
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How much radon is too much? Radon detectors measure levels in picocuries per liter (pCi/L) to indicate average, year-round radon levels. If your home measures between 2-4 pCi/L, consider taking steps to reduce radon levels. Higher than 4? Confirm the results, then take immediate action. The EPA offers more information here.