Post-Mitigation Radon Verification Testing

Who this is for

• Homeowners who recently had a mitigation system installed
• Buyers verifying a seller-installed system
• Sellers documenting a working system as part of a listing

When it may be appropriate

• After a mitigation system has been running for the recommended startup period
• Periodically after installation to confirm continued performance
• Before a real-estate transaction that references the mitigation system

How the process works

1. 1
   Confirm system status

   We confirm the system has been operating and gather any relevant background details.
2. 2
   Deploy the test

   The device is placed under closed-house conditions in an appropriate location.
3. 3
   Deliver the reading

   You receive a written result along with a plain-language interpretation.

What to expect

• An independent reading — we do not install mitigation systems ourselves
• Clear guidance on what to do if the reading is not what was expected
• Documentation suitable for your records or a transaction file
• A plain-language interpretation of the reading relative to the EPA action level

What to expect: post-mitigation verification

Before the test

• Confirm the mitigation system is running and has been operating for at least the startup period (usually 24+ hours).
• Verify the system manometer is reading in its normal range.

During the test

• The device is placed at the lowest livable level under closed-house conditions.
• The mitigation fan remains on for the entire test period.

After the test

• You receive a written report documenting the reading.
• If the reading is at or below acceptable levels, the system is verified. If not, you contact the installer for adjustment.
• Plan for periodic retesting — the EPA recommends every two years for homes with mitigation systems.

Frequently asked questions