A high radon test is a starting point, not a verdict
You opened the report, saw a number above 4, and searched your way here. So let’s start with the two facts that matter most.
First: around Harrisburg, a high result puts you in very large company. This part of Pennsylvania sits on rock that produces a lot of radon, and elevated readings come back constantly, from new construction and old rowhouses alike. The published numbers for the region are collected in radon levels in your area, and they’ll make you feel less singled out.
Second: this is one of the most solvable problems a house can have. Radon mitigation is a mature trade with decades of practice behind it. There’s no demolition, no remediation crews in suits, no stigma on the deed. A system gets designed, installed in a day’s ballpark, and then — this is the important part — a follow-up test proves the level came down.
Nothing about the number on your report requires action today, either. Radon risk in the published guidance is about long-term exposure, years of it, not a bad week. You have time to confirm the reading, understand the options, and fix it properly.
So here’s the path this page walks: what your number means against the published scale, when it’s worth retesting before you spend money, and what the fix involves. By the end, the report in your hand should feel like a to-do item instead of an alarm.
Where your number sits, per published guidance
Under 2 pCi/L
- What EPA guidance says
- Below the consider-fixing range
- Typical next step
- Keep the report, retest in a few years
2–4 pCi/L
- What EPA guidance says
- Consider fixing the home
- Typical next step
- A confirming test, then decide
4 pCi/L and above
- What EPA guidance says
- Fix the home
- Typical next step
- Plan mitigation and a verification retest
| Your result | What EPA guidance says | Typical next step |
|---|---|---|
| Under 2 pCi/L | Below the consider-fixing range | Keep the report, retest in a few years |
| 2–4 pCi/L | Consider fixing the home | A confirming test, then decide |
| 4 pCi/L and above | Fix the home | Plan mitigation and a verification retest |
The scale comes from EPA consumer guidance. It describes ranges, not any one household's risk.
Reading your number against the published scale
The EPA’s action level is 4 picocuries per liter. At or above it, the guidance says fix the home. Between 2 and 4, the guidance says consider fixing. Below 2, retest periodically and move on with your life. That’s the whole scale. And note what it is: population-level guidance about ranges. It doesn’t quantify what your particular number means for your particular family, and neither should any contractor. The unit itself, and why the guidance is built this way, is unpacked in what the numbers mean.
Now, should you trust one reading? It depends on where it sits. Radon levels move with seasons, with weather, with how sealed the house was. A short-term screen that reads 4.6 in January could plausibly read 3.5 in May. So when a number lands near the line, a follow-up test is a reasonable move before anyone spends money. A long-term test gives the truest average; a second short-term test at least confirms the first wasn’t a fluke.
A clearly high result is a different story. When a screen comes back at 12 or 20, retesting rarely changes the conclusion, and most owners move straight to reducing the level.
And a deadline changes the calculus entirely. In a home sale, there’s usually no room for a 90-day confirmation test. The short-term protocol result is the number the deal runs on, and the sequencing compresses. More on that below.
Have the number in hand? An estimate turns it into a plan.
What fixing it actually involves
The fix is a machine, and a modest one. A radon mitigation system collects soil gas from beneath your home, through a suction point drilled in the slab, a sealed sump, or a membrane over a crawlspace floor. A continuously running fan vents it through a pipe above the roofline. The gas exits over the roof and dilutes into the outdoor air instead of seeping into your basement.
Getting there runs in three beats. An assessment reads your foundation: slab, basement, crawlspace, sump, or some combination, because the foundation decides the design. The design places the suction points and routes the pipe for your house specifically. Then installation, which for a typical single-family home is measured in hours, not days.
Then comes the part that separates honest radon work from a sales pitch: verification. Systems are designed to bring levels below the action level, but no one can promise your exact outcome number in advance, because every foundation behaves a little differently. What can be promised is a post-installation test that measures the result in writing. That retest is the honest version of the guarantee — a documented number instead of a handshake claim.
Afterward, the system mostly minds itself. A small gauge on the pipe shows the fan is pulling, and periodic retesting every couple of years confirms the number is holding.
If you want to see the whole machine before talking to anyone, how radon mitigation works walks through every component with pictures. When you’re ready to put your own house in front of someone, mitigation is where the money conversation starts.
High result in the middle of a home sale?
Take an extra breath, because the deadline is doing most of the shouting here.
An elevated radon test is one of the most routinely resolved inspection findings in real-estate deals across this region. Agents have a playbook for it: the finding goes into the repair negotiation, someone takes responsibility for the fix, mitigation gets scheduled around the closing, and a verification retest gets documented for the file. Deals close over radon constantly. They rarely die over it.
What the deadline actually changes is sequencing: less time for confirmation testing, more need to get scheduling started promptly. The playbook, the who-pays norms, and the documentation are all covered in radon in a home sale, written for exactly the spot you’re standing in.