Post-Mitigation Radon Retest in Berks County, PA

A mitigation install isn't finished until a post-mitigation retest confirms the home reads below 4.0 pCi/L. Without it, the install is unverified — neither homeowner nor installer has data showing the system is doing its job. Every install in Berks County includes a retest as standard.

When the retest runs

Post-mitigation tests run in two windows:

• 24-hour quick-check — a continuous radon monitor placed in the lowest livable level the day after the fan is energized. Confirms the system is moving in the right direction immediately.
• 30-day verification — a longer-window test, either a second CRM run or an alpha-track detector, confirming the system holds steady under varied conditions (heating-on, weather changes, normal house operation).

What the result has to be

The EPA action level is 4.0 pCi/L. A post-mitigation retest at or above 4.0 means the system needs adjustment — not a new install, just a tweak. Common adjustments in Berks County:

• Relocate or add a suction point if the original placement left a dead zone.
• Upsize the fan if soil permeability is lower than estimated.
• Seal additional slab penetrations (cold-air returns, plumbing chases) that are leaking.
• Tighten the sump pit cover if the seal isn't airtight.

Adjustments are included in the install cost. If the home doesn't read below 4.0 the first time, the system gets adjusted until it does — at no additional charge.

Retesting an existing system

Mitigation systems aren't fire-and-forget. Fans wear out (the typical fan service life is 8–15 years), manometer tubing can develop a leak, and slab seals can fail. EPA recommends retesting any mitigated home every two years and after any major work that disturbs the foundation envelope.

A retest on an older system that comes back high doesn't necessarily mean a new install — often a fan replacement plus a manometer check is enough to bring it back below 4.0. A short inspection determines which.