Radon testing
A test is the only way to know your radon level. Here's how to do it well, and when to bring in a certified tester.
Two houses on the same Morningside street can test very differently. Testing tells you whether you need a system at all, and testing after a system is installed tells you whether it's working.
Which test fits my situation?
| Test | How long | Use it for |
|---|---|---|
| Short-term kit | A few days | A first look, or a quick check after a fix |
| Long-term kit | More than 90 days | A truer picture of your average across seasons |
| Continuous monitor | Usually 2 days or more, logged hour by hour | Home sales and professional pre- and post-mitigation tests |
How do I run a kit correctly?
- Use the lowest floor you live on: a finished basement, or the main floor if the basement is just storage.
- Keep windows and outside doors shut, apart from normal coming and going, for 12 hours before and during a short-term test.
- Set the kit about breathing height, away from the sump, floor drains, exterior walls, kitchens, bathrooms and vents.
- Log the start and stop times and mail it to the lab right away.
Where can I get a kit?
Iowa's Radon Hotline, 1-800-383-5992, sells low-cost kits and answers radon questions. Iowa HHS has also offered one free kit per household, while supplies last, through the American Lung Association or the Healthy Hometowns program, depending on the county. Hardware stores sell kits too.
When do I need a certified tester?
Iowa's radon testing rules, effective July 1, 2026, require certification for anyone who measures radon in a building they don't own for compensation, including out-of-state businesses serving Iowa residents. Testing your own home doesn't need a certificate. A certified measurement specialist is the usual choice for home sales and for the test after a mitigation system goes in. In South Sioux City, Nebraska requires a DHHS radon license.
My number is high. What now?
Iowa HHS says not to make a mitigation decision on one test. Run a second test to confirm, then call a credentialed mitigation company if the level holds at 4 pCi/L or above. Between 2 and 4, the EPA suggests considering a fix.
The radon company prices the job after it understands your foundation, usually after a visit. We don't quote prices, and a number over the phone is only a ballpark, not a written bid.
Where we connect you with help
Common questions
Is winter a good time to test?
Yes. With the house closed up and the furnace running, a winter test shows conditions you live with for months. A long-term test evens out the seasons.
Can the mitigation company test its own system?
Iowa's rules call for the pre- and post-mitigation tests to be done by a measurement specialist from a different firm, or by the homeowner or occupant.
Related services
More background: Siouxland radon guide.
Radon number higher than you hoped?
Call and a local radon mitigation company will look at the house and quote a system.