Radon: Test the Lowest Level of Your Home
Spot it
You can't see, smell or taste radon, so the only sign is a test result. It enters through cracks and openings in floors and walls that touch the ground, so a basement, a slab-on-grade laundry room or any ground-contact living space is where to look first. If you have never tested, that is the finding.
Fix it
Test first. EPA's Citizen's Guide says a short-term test (two days to 90 days, depending on the device) goes in the lowest lived-in level of the home, in a regularly used room but not the kitchen or bathroom; if the result is 4 pCi/L or higher, follow up with a second test. EPA recommends fixing a home at 4 pCi/L or more, and suggests considering a fix between 2 and 4 pCi/L because there is no known safe level of radon. Fixing is done by a qualified mitigation professional; your state radon program can supply test kits (some states offer them free or discounted) and point you to professionals. Full walk-through: radon home test guide.
Check your address to see what the public records say about this for your home.
Safer swaps
What actually fixes this — the category to look for, not a brand we were paid to name.
Ask your state radon program about a free or discounted test kitHabit
Free in some states; EPA points to state radon programs for kits
Short-term radon test kit for the lowest lived-in level
EPA: testing is the only way to know
Qualified radon mitigation professional, if the result is 4 pCi/L or higher (consider at 2-4)Service
EPA's recommended fix; find one through your state radon program or the NRPP and NRSB credentials
Our picks for this
The products we would buy for this are in our radon test kits: what the 4 pci/l number actually means guide.
Sources cited
Sources
- EPA estimates radon causes about 21,000 lung cancer deaths a year in the U.S., about 2,900 among people who never smoked — U.S. Environmental Protection Agency, 2026 (how we check this source)
Every source we cite is checked against our criteria first — see how we check our sources.