What Is a Radon Inspection Report?

A radon inspection report documents the results of radon gas testing in a building, including the test methodology, device placement, test duration, measured radon concentration, and comparison against the EPA action level of 4.0 pCi/L. It provides the property owner, buyer, or occupant with a clear record of the radon risk level and whether mitigation is recommended.

Radon is a naturally occurring radioactive gas that seeps into buildings from uranium decay in soil and rock. It's the second leading cause of lung cancer in the United States — responsible for an estimated 21,000 deaths annually. Because radon is colorless and odorless, testing is the only way to know if a building has elevated levels, making the inspection report a critical health and safety document.

Certified radon inspectors follow strict protocols for device placement, test duration, and closed-building conditions to ensure accurate results. The inspection report documents compliance with these protocols, which is essential for real estate transactions — a poorly documented test can be challenged, delayed, or invalidated, forcing retesting and potentially derailing a closing.

What's covered

• Test Device Details: Test method documentation, Device type and model, Serial number tracking, Calibration verification
• Placement & Location: Lowest livable level, Floor level documentation, Foundation type assessment, Placement protocol compliance
• Results & Analysis: Radon level (pCi/L), EPA action level comparison, Mitigation recommendation, Test duration verification
• Test Integrity: Closed building conditions, Weather documentation, Tamper indicator check, Protocol compliance record

Why this checklist

EPA protocol compliance built into the form. EPA and AARST standards require specific documentation for radon tests — device type, serial number, placement location, test duration, and closed-building conditions. This template captures every required data point so your reports meet the standard real estate agents, lenders, and state regulators expect.

Clear EPA action level comparison. The EPA action level of 4.0 pCi/L is the threshold that drives decisions. This template provides a clear above/below comparison with the measured result, eliminating ambiguity for buyers, sellers, and real estate agents who need to understand the bottom line quickly.

Test integrity documentation prevents challenges. Radon tests get challenged — especially in real estate transactions where the result affects the deal. Documenting closed-building conditions, tamper indicators, weather, and device placement creates a defensible record that holds up when someone questions the validity of your test.

Mitigation recommendation with context. A radon level above 4.0 pCi/L requires mitigation, but context matters. This template captures foundation type, floor level, and building condition so your mitigation recommendation includes the information a mitigation contractor needs to design an effective system.

How to Complete a Radon Inspection Report

• Record property and certification details — Document the property address, inspection date, your name, and radon certification number. State certification is required in most jurisdictions for radon testing — include your credential number to establish the report's validity for real estate and regulatory purposes.
• Document the test device and method — Record the test method (short-term, long-term, or continuous monitor), device type (charcoal canister, alpha track, continuous radon monitor, or electret ion chamber), and the device serial number. This traceability is required by AARST standards and allows verification of device calibration records.
• Record device placement details — Document exactly where the device was placed — the lowest livable level, the specific room, and the distance from walls, floors, and windows. EPA protocols require placement in the lowest livable area, at least 20 inches above the floor, away from exterior walls, and not in kitchens, bathrooms, or high-humidity areas.
• Log test start and end times — Record the exact date and time the test began and ended. Short-term tests must run a minimum of 48 hours; continuous monitors typically run 48-96 hours. The test duration must meet your device manufacturer's requirements and state regulations — tests that are too short are invalid and must be repeated.
• Record results and compare to EPA action level — Enter the measured radon concentration in pCi/L and indicate whether it falls below or at/above the EPA action level of 4.0 pCi/L. If the result is between 2.0 and 4.0 pCi/L, note that the EPA suggests homeowners consider mitigation in this range as well. Document whether mitigation is recommended.
• Verify test integrity and conditions — Document whether closed-building conditions were maintained throughout the test (windows and doors closed except for normal entry/exit). Note the weather during the test period and check tamper indicators. If conditions were compromised, the test may need to be repeated — document your assessment of test validity.

Common Mistakes in Radon Inspection Reports

Placing the device in the wrong location. The test device must be placed on the lowest livable level — not the lowest level, the lowest livable level. An unfinished basement that will never be occupied doesn't qualify unless the buyer plans to finish it. And placement matters within the room: at least 20 inches off the floor, 12 inches from walls, and away from drafts, humidity, and heat sources.

Not verifying closed-building conditions. Closed-building conditions must be maintained for 12 hours before the test starts and throughout the entire test duration. Windows and exterior doors must remain closed except for normal entry/exit. If the homeowner ran the whole-house fan or left windows open, the test is compromised. Document your verification — don't just assume conditions were maintained.

Running the test too short. Short-term tests require a minimum of 48 hours. Continuous monitors should run at least 48 hours and ideally 96 hours for more reliable results. Pulling a test at 44 hours because it's convenient invalidates the result. Set clear pickup times and stick to them.

Missing the serial number or calibration data. Every test device has a serial number that links to its calibration record. Without this traceability, the test result can't be verified and may not be accepted by state regulators or real estate parties. Record the serial number on every report, every time.

Not documenting weather conditions. Barometric pressure and weather patterns affect radon entry rates. Heavy rain or rapid pressure drops can temporarily elevate radon levels, while dry, stable weather may produce lower readings. Documenting weather provides context for the result and helps explain anomalous readings.

Common questions