Radon testing is something a lot of homeowners have heard of but few fully understand, and in New Jersey, it deserves more attention than it typically gets. Radon is a colorless, odorless, tasteless radioactive gas produced naturally by the breakdown of uranium in soil and rock. It seeps into homes through cracks in foundations, gaps around pipes, and other openings in the building envelope, and because it has absolutely no sensory cues, the only way to know whether a home has elevated levels is to test for it. For New Jersey residents, that matters more than many people realize.
Why New Jersey Is a High-Risk State for Radon
New Jersey is not a state that homeowners typically associate with radon concerns, but the data tells a different story. The EPA has identified significant portions of New Jersey, including areas of Middlesex, Somerset, Morris, and Hunterdon counties, as having elevated radon potential based on geology, soil type, and existing test results. The Garden State’s underlying geology, which includes uranium-bearing rock formations across much of the northern and central parts of the state, creates conditions where radon can accumulate at levels that warrant attention.
This is not a small or unlikely risk. New Jersey has consistently reported elevated indoor radon levels in residential properties at rates that put it among the states where radon testing is not just recommended but genuinely important for protecting long-term health.
How Radon Testing Works
Radon testing is non-invasive and straightforward. Short-term tests run for a minimum of 48 hours and use a small passive detector placed in the lowest livable area of the home according to established protocol. Long-term tests run for 90 days or more and provide a more accurate picture of average annual radon exposure over time.
Professional radon testing conducted during a home inspection uses calibrated devices placed and collected according to state and EPA guidelines. This matters because proper placement, undisturbed test conditions, and certified laboratory analysis are all factors that affect the accuracy of results. Consumer-grade DIY kits exist, but professional radon testing is the standard for real estate transactions and the most reliable option for any homeowner who wants results they can act on with confidence.
Understanding Your Radon Test Results
Radon is measured in picocuries per liter of air, abbreviated as pCi/L. The EPA recommends taking corrective action when indoor radon levels reach 4 pCi/L or higher. Levels between 2 and 4 pCi/L fall into a range where mitigation is worth considering. The national average indoor radon level is approximately 1.3 pCi/L, providing a useful baseline for comparison.
Elevated results are not a reason to panic. Radon mitigation is a well-established practice, and a properly installed sub-slab depressurization system can typically reduce indoor radon levels to below 2 pCi/L in most homes. The cost of mitigation is manageable, and the protection it provides for the people living in the home is significant.
When to Schedule Radon Testing
The most common trigger for radon testing is a home purchase, and for good reason. Buyers want to know what they are moving into, and sellers benefit from having documented results available. But radon testing is equally relevant for current homeowners who have never tested, who have completed renovations that changed the home’s ventilation or foundation, or who have simply not tested in several years. The EPA recommends retesting every two years and following any significant changes to the home.
Frequently Asked Questions
Is radon testing required for home sales in New Jersey? New Jersey does not legally mandate radon testing for residential real estate transactions, but it is strongly encouraged by state health authorities and widely expected in the local real estate market. Many buyers include radon testing as a standard part of their due diligence.
How long does radon testing take? A short-term radon test runs for a minimum of 48 hours, with the home kept in closed-house conditions during that time. Laboratory analysis typically adds a few additional days before results are available.
If my home has a radon mitigation system already installed, do I still need radon testing? Yes. An existing mitigation system should be verified to be functioning correctly with follow-up radon testing. Systems can lose effectiveness over time if fans fail or if structural changes affect airflow patterns. Testing confirms the system is still doing its job.
Does radon only affect older homes? No. Radon levels are determined by geology and soil conditions beneath the home, not by the age of the structure. New construction and older homes alike can have elevated radon levels. Tighter construction in newer homes can sometimes result in higher indoor concentrations.
What should I do with my home during a short-term radon test? Closed-house conditions should be maintained for at least 12 hours before and throughout the testing period. This means keeping windows and exterior doors closed except for normal entry and exit. Fans that draw outside air in should not be used. Your inspector will provide specific guidance when the test is placed.
Protecting your family from an invisible but serious health risk starts with a simple test. McGowan Home Inspections provides professional radon testing across New Jersey so you have the accurate, reliable results you need to make informed decisions. Schedule your radon testing today.