Radon testing determines whether a home has a dangerous level of the gas, but not every test result carries the same weight. For a real estate closing, a refinance, or a school testing requirement, the result has to come from a currently licensed measurement professional — not a hardware-store kit. Here's what licensed radon testing in Minnesota actually costs, who's allowed to perform it, and what the process involves.
What does licensed radon testing cost in Minnesota?
Licensed radon testing in Minnesota costs less than installing a full mitigation system, and the exact price depends on whether you need a simple DIY charcoal kit, a professional short-term test, or a real estate transaction test that requires chain-of-custody paperwork and a currently licensed tester. Ask a licensed operator in your area for a current quote, since pricing varies by test type, home size, and turnaround speed.
A few things typically move the price up or down:
- Whether the result needs to be chain-of-custody (required for most closings and refinances) versus a casual DIY check.
- Short-term test (48 hours–90 days) versus a continuous radon monitor that produces a reading faster.
- Number of test locations required — larger homes or homes with multiple foundation types sometimes need more than one device.
If you're budgeting for the whole project — testing plus a mitigation system if the result comes back high — the installation side is covered in detail in our guide to radon mitigation costs in Minnesota.
Who is legally allowed to perform radon testing in Minnesota?
Minnesota requires radon measurement professionals to hold a current license issued by the Minnesota Department of Health, and real estate transactions in the state generally require results from a licensed tester rather than a DIY kit purchased off a hardware-store shelf. Anyone can buy a kit for personal curiosity, but that result typically won't satisfy a lender, buyer, or school district requirement.
The Minnesota Department of Health (MDH) maintains the state's radon licensing program, and measurement and mitigation are separate credentials — the person who tests your home isn't automatically licensed to install a system if the result comes back high. If you're in Ramsey County, Hennepin County, Dakota County, or anywhere else in the state, confirm the tester's license is active before you pay for a test that's tied to a closing deadline. An expired license can force you to redo the test and lose the window you had.
How does a licensed radon test actually work?
A standard short-term radon test runs for 48 hours to 90 days under closed-house conditions, with the device placed in the lowest livable level of the home, at least 20 inches above the floor and away from drafts, per protocols the EPA and MDH both follow. Continuous radon monitors can produce a usable average reading in as little as 48 hours.
Closed-house conditions mean windows and exterior doors stay shut, aside from normal entry and exit, for at least 12 hours before the test starts and for the entire time it's running. That's actually why winter is a reliable season for Minnesota radon testing — homes are already sealed up against the cold, which mirrors the exact conditions the test is designed to measure. Running a test during an open-window spring cleaning stretch, or with a window cracked for fresh air, can throw off the reading in either direction.
Placement rules a licensed tester follows typically include:
- Lowest livable level of the home (not an unfinished crawlspace used only for storage).
- At least 20 inches above the floor, away from exterior walls, windows, and direct airflow from vents.
- No disturbance of the device for the full test duration — moving or covering it can invalidate the result.
What counts as a dangerous radon result, and what should I do next?
The EPA's action level is 4.0 pCi/L — at or above that number, the EPA recommends installing a mitigation system, and between 2 and 4 pCi/L it's worth considering mitigation too, since levels tend to fluctuate somewhat between tests in the same home. A single reading above that threshold doesn't mean panic, but it does mean it's time for a second look and a mitigation quote.
For a full breakdown of what the pCi/L number on your report actually means for your specific home, see our guide to dangerous radon levels in Minnesota. If mitigation is the next step, most licensed operators in our network install an active sub-slab depressurization (ASD) system — here's how that process works — which uses a fan and PVC piping to pull radon from beneath the foundation and vent it above the roofline before it ever reaches living space.
Why are radon levels so high across Minnesota, including Ramsey County?
Minnesota sits on glacial till — soil deposited by retreating glaciers that's often rich in uranium-bearing minerals over fractured bedrock — which is why the state consistently reports some of the highest average indoor radon readings in the country, according to the Minnesota Department of Health. That geology doesn't stop at city limits, so testing matters whether you're in St. Paul, Minneapolis, St. Cloud, or Rochester.
This is also why a clean test from a neighbor's house, or even a prior owner's test from a few years back, isn't a substitute for your own current reading. Radon levels can vary significantly between two homes on the same block depending on foundation type, foundation cracks, sump pit sealing, and how the HVAC system pressurizes the lowest level. In Ramsey County specifically — including the Highland Park and Mac-Groveland areas of St. Paul — elevated readings are common enough that many lenders now ask for a current test as a standard closing condition, not only when a buyer specifically requests one.
This article is for general homeowner education and isn't a substitute for a licensed measurement or mitigation professional's evaluation of your specific property. Licensing requirements, acceptable test types, and closing or refinance requirements can vary by transaction and municipality — confirm current rules with the Minnesota Department of Health or your closing agent before scheduling a test.