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Post-Mitigation Radon Testing in Toledo

Installing a mitigation system is only half of the job. The other half is verifying it actually brought the home below the EPA action level. Post-mitigation testing happens twice: once at 24 hours after system startup, and again at 30 days for a longer-window confirmation.

24-hour confirmation

A continuous monitor runs for 24 hours after the fan starts. This is the “does it work” check. A correctly designed sub-slab depressurization system in a Lucas County home will typically cut radon by 85 to 99 percent within hours of startup, so a result above 2.0 pCi/L on the first re-test is a flag to revisit fan sizing or sealing.

30-day confirmation

A second test runs at 30 days under closed-house conditions. The longer window catches any pressure cycling or weather-driven variation that a 24-hour test might miss. If the 30-day result is below 4.0 pCi/L, the system is considered verified and the install warranty is in force.

If the post-test is still high

An additional suction point, a higher-static-pressure fan, or extra sealing at the slab-wall joint are the typical fixes. Adjustments are covered under the install warranty — the system is designed to bring the home below 4.0 pCi/L, not to just be installed and left.

Long-term re-tests

A radon test every two years is recommended even after a successful mitigation. Fans wear out around year eight to twelve, and slab cracks can open up over time. Catching a slow rise before it gets back into the action range is cheaper than re-mitigating.