What radon is, how it gets into a home, whether it is actually dangerous, and how worried you should really be.
Basements collect more radon than any other part of a home because they sit closest to the soil source and ventilate the least, making testing essential.
Read the guide →The EPA's radon zone map shows which US counties and states face the highest average indoor radon levels, and why your specific home can still surprise you.
Read the guide →Radon levels are shaped by soil geology, foundation type, and indoor pressure. Here is what pushes levels high and why two neighboring homes can read so differently.
Read the guide →Iowa, North Dakota, Pennsylvania, and a cluster of Midwest states top every radon survey. Here is what the EPA data shows and what to do about it.
Read the guide →The U.S. EPA sets the 4 pCi/L action level that all 50 states follow, but average radon concentrations and state programs vary considerably by region.
Read the guide →The EPA's 4 pCi/L action level is not a safety cutoff. Here is what the number actually means, how it was set, and what to do if your home exceeds it.
Read the guide →pCi/L is the unit US labs use for indoor radon. Learn what it means, why the EPA set 4 pCi/L as the action level, and how it compares with Bq/m3 standards worldwide.
Read the guide →A plain-language look at the EPA's 4 pCi/L action level, the U.S. home average of 1.3 pCi/L, and how to put your own test result in context.
Read the guide →The EPA sets an action level at 4 pCi/L, but no radon level is free of risk, and US homeowners need to understand what any test result actually means.
Read the guide →The EPA acts at 4 pCi/L, but radon risk is a gradient with no safe threshold. Here is what different readings mean and what US homeowners should do.
Read the guide →Radon is a natural radioactive gas that seeps into homes from soil. Learn what it is, how it gets in, and why the EPA calls it a real lung cancer risk.
Read the guide →How to test, short-term vs long-term kits, what a good test costs, and how to read your result against the EPA and WHO levels.
Browse Testing →How a sub-slab depressurization system actually works, what mitigation costs, and where DIY makes sense versus hiring a pro.
Browse Mitigation →Radon in real estate: testing during a sale, whether to buy a house that already has a system, and who pays for the fix.
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