A radon test at or above 4 pCi/L, the EPA action level, means it is time to plan a mitigation system. Results between 2 and 4 are also worth discussing. We connect York homeowners with a local contractor who reviews the result, looks at the house, and designs a system to bring the level down.
Understanding Your Test Result
Radon is measured in picocuries per liter of air, written pCi/L. The EPA recommends fixing a home at 4 pCi/L or higher and suggests considering a fix between 2 and 4. There is no level that is considered completely safe, so lower is better.
Before planning a system, it helps to know how the test was done. A short-term test placed in the basement with windows closed gives a different picture than a long-term test in a first floor bedroom. If the result is close to the line, a second test can help confirm it. If it is clearly high, most homeowners move straight to an estimate.
Bring the lab report or kit result to the estimate. The number and the placement help the contractor size the fan and decide how many suction points the house may need.
How the System Is Designed
Most homes are mitigated with active soil depressurization. A hole is made through the slab, or a membrane is laid in a crawl space, and a pipe connects that space to a fan. The fan pulls soil gas from under the house and vents it above the roofline, away from windows.
The design depends on the foundation. Poured slabs with a good gravel layer often need only one suction point. Homes with block walls, stone foundations, crawl spaces, or a sump pit may need extra suction points or sealing work. The contractor also checks how the pipe can be routed, either through the house to the attic or up the outside wall.
Higher starting levels do not always mean a bigger system. What matters most is how easily air moves under the slab, which the contractor can test during the estimate.
Retesting After the Install
Once the system is running, a retest confirms it is working. Many guides suggest waiting at least a full day after the fan starts, then running a short-term test within the first month. Place the kit in the lowest lived in area, keep windows and doors closed, and follow the kit directions closely.
The result should be well below the action level. If it is not, the contractor can check suction, look for leaks, and adjust the system. That might mean sealing an opening that was missed or adding a second suction point.
After that, plan to test every couple of years and after any major renovation. Check the gauge on the pipe from time to time so you notice a problem before the next test.
Turn a High Number Into a Plan
A high radon result is a problem with a well known fix. A careful look at the house is always the best starting point. Knowing the steps ahead of time takes much of the stress out of the process. With the right information, the next step is usually simpler than it first seems. Call us and we will connect you with a local contractor who will look at your York home, explain the system in writing, and walk you through the retest. The written quote comes with no obligation, and the decision is yours.
Frequently Asked Questions
How soon can elevated radon be mitigated in a York home?
Once you approve a written quote, many installs can be scheduled within a week or two, depending on the provider's calendar. Most residential systems are installed in a single day. If you are under contract on a home, tell us when you call so the provider can plan around your timeline.
What system is used when levels are well above the action level?
Most homes still use active soil depressurization, even at high levels. The contractor may add suction points, seal a sump or large cracks, or choose a stronger fan, depending on how air moves under the slab. A diagnostic check during the estimate helps decide what the house actually needs.
When should we retest after mitigation?
Many guides suggest waiting at least a full day after the fan starts, then testing within about a month. Use a short-term kit in the lowest lived in level with windows and doors closed. After that, test every couple of years and after major renovations to make sure the system keeps working.