Specialized diagnostics · D-05
Radon Testing
48-hour continuous radon screening with a clear result against the EPA action level, and next steps if mitigation is needed.
Specialized diagnostics · D-05
48-hour continuous radon screening with a clear result against the EPA action level, and next steps if mitigation is needed.
Overview
Radon is a naturally occurring radioactive gas that enters homes through the foundation. It is the leading cause of lung cancer among non-smokers, and the only way to know your level is to test.
We place a continuous monitor in the lowest livable level for at least 48 hours and report the average result, hourly readings and a recommendation.
See what a Caliber report looks likeMethod
Continuous radon monitor, 48-hour minimum
Reference
EPA action level of 4.0 pCi/L
Best for
Every home purchase in Northern Illinois
Deliverable
Average result, hourly readings and recommendation
Pairs with
Pre-purchase home inspection
Why this evaluation matters
Radon is a colorless, odorless, tasteless radioactive gas produced by the natural breakdown of uranium in soil and rock—making it impossible to detect during a visual home inspection without specialized monitoring equipment.
The first step in mitigation is testing. Because no level of radiation exposure is considered completely safe, governments and health organizations worldwide have established action levels to guide when indoor radon concentrations must be reduced. The World Health Organization (WHO) International Radon Project recommends an action level of 2.7 pCi/L (100 Bq/m³) for radon in the air, while the US EPA and Illinois IEMA recommend mitigation at 4.0 pCi/L or higher.
Much of McHenry, Kane, and the surrounding Chicagoland counties sit in EPA Radon Zone 1 and Zone 2. Air-radon levels fluctuate naturally on a daily and seasonal basis due to barometric pressure swings, wind, closed windows, and exhaust fan operation. While a short-term test (under 90 days) captures a snapshot rather than a year-round average, a 48-hour continuous test is the industry standard during a real estate transaction to quickly identify unhealthy conditions before closing.
Installing a post-closing radon mitigation system typically costs $1,200 to $2,500+. Even if a home already has a mitigation system installed, the US EPA recommends retesting every 2 years to verify the fan and system are functioning properly, and testing all homes at least once every 5 years.
(Note: Per US EPA guidance, radon in air is the primary health threat; radon-in-water testing requires a separate laboratory water sample and is typically considered on private well properties or when air concentrations are elevated).
Scope
A controlled, documented test you can rely on in negotiation.
Hourly measurements over the full test period.
Movement and interference sensors on the monitor.
Clear instructions to keep results valid.
Average level compared to the 4.0 pCi/L action level.
Plain next steps if the result is elevated.
A follow-up test to check the system is reducing radon levels.
Clear results
Your result is easy to read and easy to share with the seller or a mitigation contractor.
Average radon level
Hourly reading chart
Test conditions documented
Recommendation based on the result
A minimum of 48 hours. The monitor is placed at the start of your inspection and collected afterwards.
Radon is fixable. Mitigation systems typically reduce levels significantly, and the result gives you grounds to negotiate the cost with the seller.
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