Radon Testing for New York and New Jersey Homes

Radon is the second leading cause of lung cancer in the United States — and it's invisible, odorless, and entirely undetectable without a test. If your home is in a county with elevated radon potential, the only way to know your actual exposure level is to measure it.

Why Radon Testing Matters in the NY Metro Region

Radon is a naturally occurring radioactive gas that forms from the decay of uranium in soil and rock. It enters buildings through foundation cracks, floor drains, and gaps around utility penetrations — accumulating to dangerous concentrations in basements and lower floors without any visible sign. The EPA estimates that radon causes approximately 21,000 lung cancer deaths in the United States each year, making it the leading environmental cause of lung cancer among non-smokers.

 

While New York City's dense urban geology tends to produce lower radon readings than more rural areas, the outlying counties tell a different story. Westchester, Rockland, Orange, and parts of the Hudson Valley sit on geological formations known to generate elevated radon levels. Homeowners in these areas — and anyone purchasing or selling a property there — should treat radon testing as a baseline, not an afterthought.

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How We Conduct Radon Gas Inspections

Radon testing follows a structured protocol designed to produce accurate, defensible results — not a snapshot reading that varies with weather or ventilation conditions. Oasis uses both short-term and long-term testing methods depending on the client's situation, the purpose of the test, and what the results will be used for.

What Radon Levels Are Considered Dangerous

The EPA action level for radon is 4 picocuries per liter (pCi/L) of air. At or above that threshold, the agency recommends mitigation. Levels between 2 and 4 pCi/L fall into a gray zone where mitigation is worth serious consideration, particularly in homes with children or in households where someone already has a respiratory condition. The average indoor radon level in U.S. homes is approximately 1.3 pCi/L — but in elevated-risk counties, readings well above 4 pCi/L are not unusual.

Short-Term Radon Testing

Short-term tests typically run 48 to 96 hours using charcoal canister or electret ion chamber devices placed in the lowest livable area of the home. This method is most appropriate for real estate transactions, initial screening, or situations where a result is needed quickly. Devices are placed under closed-house conditions to minimize variability, then sent to an accredited laboratory for analysis.

Long-Term Radon Testing

Long-term tests run for 90 days or more using alpha track detectors. Because radon levels fluctuate with seasons, soil moisture, and indoor pressure dynamics, a longer test produces a more accurate picture of average annual exposure. Long-term testing is particularly valuable for homeowners who want a reliable baseline rather than a point-in-time reading — and for those making decisions about renovation, occupancy, or mitigation investment.

Post-Mitigation Clearance Testing

After a radon mitigation system is installed, a follow-up test is the only way to confirm it's working. Oasis conducts post-mitigation radon testing as an independent third party — separate from the contractor who installed the system. This matters because the same firm that installs a mitigation system has a financial interest in reporting success. An independent clearance test gives you an unbiased result you can trust.

Real Estate Radon Testing

Radon testing is a standard component of real estate due diligence in elevated-risk counties. Whether you're a buyer who wants independent results before closing, a seller preparing to disclose accurately, or an agent coordinating inspections across multiple properties, Oasis provides testing that meets real estate transaction timelines and produces laboratory-backed reports suitable for disclosure documentation.

Independent Testing With No Remediation Conflict

Oasis Indoor Environmental is an inspection and testing firm. We do not perform radon mitigation. That means when we give you a radon result, there is no financial incentive attached to what that number says. If your levels are below the action threshold, we tell you that clearly. If they're elevated, we explain what the number means and what your options are — and you can pursue mitigation through any contractor you choose.

 

This independence is built into our model, and it's the reason clients come to us specifically when they want a result they can rely on. Nearly 20 years of serving the NY metro area has taught us that trust is earned through transparency, not upselling.

Radon Testing Questions, Answered

  • Do I need a radon test if I live in New York City?

    The five boroughs are generally classified as lower radon risk, but that doesn't mean individual units are safe to assume. Basement apartments, garden-level units, and older buildings with deteriorating foundations can still accumulate radon above the EPA action level. Testing is the only way to know for certain — and the cost of a test is negligible compared to the cost of long-term exposure.

  • How much does radon testing cost?

    Radon testing costs vary based on the method used, the size of the property, and whether the test is short-term or long-term. Contact us for a specific quote — we provide transparent pricing before any inspection is scheduled, with no hidden fees.

  • How long does a radon test take?

    Short-term tests run 48 to 96 hours under closed-house conditions. Long-term tests run 90 days or more for a more accurate annual average. For real estate transactions, short-term testing is typically used to meet closing timelines.

  • Can I use a DIY radon test kit instead?

    DIY kits from hardware stores can provide a general indication of radon levels, but they vary in accuracy depending on placement, closed-house conditions, and laboratory processing. A professionally conducted test follows EPA measurement protocols, uses accredited laboratory analysis, and produces a documented report suitable for real estate disclosure, insurance purposes, or legal proceedings — something a kit cannot provide.