Remember radon? This invisible, odorless, poisonous gas may no longer be in the headlines, but it hasn’t gone away. A by-product of naturally occurring uranium in soil, rocks, and groundwater, it can be found at unsafe levels in nearly 1 of every 15 homes, according to EPA. “It’s a radioactive gas, and it causes lung cancer,” says Bill Long, director of the agency’s Center on Radon and Air Toxics. And while most people don’t test unless they’re buying or selling a home, “we recommend testing every couple of years, and after a major renovation,” Long says. Leaky ducts, kitchen vent hoods, fireplaces—anything that decreases the air pressure inside a house relative to the outside—have the potential to pull radon from the soil around the foundation, and cause an unsafe buildup of the gas.
Geologists have identified radon hot zones, but any home in any area can have a radon problem: new or old, well sealed or drafty, with or without a basement. When radon levels exceed 4 picocuries per liter, a certified pro can install a system to suck the gas safely out of the house. Some test kits take quick snapshots, while others offer an average over time. Smart-home radon detectors can work continuously and monitor humidity and temperature as well as radon. EPA suggests installing these devices in the lowest lived-in level of a home. But skip kitchens and baths, due to their exhaust fans.
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