Healthy Indoors Magazine - USA Edition

40 | January 2019 Radon: The IAQ Menace We Ignore By Henry Slack W hen we run through the list of IAQ problems, most of us in the field probably think like this: • Mold • VOCs • Asthma triggers • CO/combustion gases When pressed, we might add secondhand smoke to this list, although that's usually not why anyone calls an IAQ professional (Instead, they scream in frustration at their in- law or neighbor who smokes). But we forget one of the pollutants that kills the most people: RADON! We also forget fine particulates (PM2.5), but that's a story for a different issue! We can't see or smell radon, but — it's radioactive. If it were on TV, it's be shown as a green, pulsing light, maybe with an alarm sound, so you'd know to be worried. But it's not on TV, because no one can see it. It's not much in the public's mind, either. And yet, for all the public's worry on mold, radon is much more deadly, killing 20,000 a year in the U.S. alone. It's 30- 40x deadlier than combustion gases, which only kill a few hundred. Lung cancer (of which, radon is the second high- est cause) is #3 in cancer mortality, just behind leukemia and lymphoma. Radon was first officially noticed in the U.S. thanks to the nuclear power industry. A guy working at a new plant set off the radiation alarms at his workplace. He clearly had radia- tion exposure — but it was before the plant had any radio- active materials. They found radon at his house, measured at over 2,000 picoCuries per liter (or pCi/L). For reference, EPA recommends action at any level over 4 pCi/L. He and his family had 500x that exposure! After officials found radon in this home, they tested other places and realized how widespread radon was. Congress passed the Indoor Radon Abatement Act in 1988, which established technical assistance and grants for state programs. EPA also established their Action Lev- el of 4 pCi/L, with recommendations that if it's over 200 pCi/L, the home should be vacated until it is fixed. Inci- dentally, 4 pCi/L is 35x more than you can be exposed to at a nuclear plant boundary. Radon levels below 4 pCi/L are not "safe", though. It's a technology-based number, not health-based. Even as low as 2 pCi/L, EPA recommends that homeowners consider installing a radon system. A panel of international experts worked with the World Health Organization (WHO) and suggested that national reference levels be set at 2.7 pCi/lL To repeat: There is no known safe level of exposure to radon. At 20 pCi/L, the lung cancer lifetime risk is 26% for smokers, 3.6 for non-smokers. Since the risk is cumula- tive, everyone can reduce their cancer risk by fixing radon problems. Where does radon come from? It's a natural product formed as uranium breaks down. There's uranium in many locations, including soil, water from wells (sometimes), and even concrete and granite. We had stories in the media a few years ago about granite countertops as a source for radon, but there's much more concrete than granite in most homes, hence the possibly greater concern with concrete indoors. Homes with sufficient outdoor air ventilation gen- erally don't have a problem with radon, however. continued on page 16

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