Why Test for Radon During Your Inspection?
Radon is the #2 cause of lung cancer. It is a naturally occurring, radioactive gas that is odorless, tasteless, and invisible. Without professional testing, you cannot know if it is building up to dangerous levels inside your home.
The Benefits of Testing
Adding a radon test to your home inspection is a critical safety step. Here is what it does for you:
Detects Health Risks: The EPA has set specific safety limits for radon. Testing confirms if your home exceeds these levels so you can act immediately.
Identifies Problems Early: Catching high radon levels before you close the deal allows you to negotiate mitigation (repair) costs with the seller rather than paying for them yourself later.
Protects Your Investment: A safe home is a valuable home. Documenting that the home is radon-free (or properly mitigated) protects your property value and ensures a smoother sale in the future.
Provides Peace of Mind: Knowing the air quality in your new home allows you to move in with confidence, knowing your family is safe from long-term exposure.
When to Test
While some states require radon testing by law, others do not. Do not assume it is included. Always request a radon screening as part of your inspection package.
The EPA recommends testing:
During any real estate transaction (buying or selling).
Every two years for maintenance.
After any major renovation or structural change to your home.
Radon in Water — New Jersey Radon Testing & Safety
Radon isn’t just an air quality concern. In New Jersey, radon can also enter your home through groundwater — especially private wells — and contribute to health risks both through inhalation and ingestion. Understanding radon in water, how it’s measured, and why specialized testing matters can protect your family and help you navigate real estate transactions with confidence.
What Is Radon in Water?
Radon is a naturally occurring radioactive gas that results from the breakdown of uranium in soil and rock. It can dissolve into groundwater that supplies private wells, especially in regions with uranium-rich geology.
Unlike surface water from lakes or rivers — where radon naturally escapes into the air before reaching your tap — groundwater from wells can carry dissolved radon all the way into your home plumbing system. When that water is agitated — by showers, dishwashing, laundry, or other household activities — radon is released into indoor air. (CT.gov)
Health Risks of Radon in Water
Inhalation Risk
Timary health risk from radon comes from brehe prathing the gas after it is released into indoor air. Radon decays into radioactive particles that can get trapped in lung tissue and increase the risk of lung cancer over a lifetime. Radon in indoor air is the second leading cause of lung cancer in the U.S. (US EPA)
Ingestion Risk
Drinking water with elevated radon does slightly increase lifetime risk of internal cancers, particularly stomach cancer. However, this ingestion risk is much smaller than the inhalation risk associated with radon released into the air. (US EPA)
Radon in water typically contributes a small percentage of total radon exposure — roughly 1 pCi/L of radon in air per 10,000 pCi/L of radon in water — but agitation during routine household use can release significant amounts into indoor air. (CT.gov)
Radon in Water in New Jersey
New Jersey does not currently have an official Maximum Contaminant Level (MCL) for radon in water, but the New Jersey Drinking Water Quality Institute has recommended a guideline of 800 pCi/L. Past considerations have ranged from 300 to 4,000 pCi/L as potential action thresholds. (radata.com)
Radon levels can vary widely between wells even in neighboring properties — test results depend on local geology and well depth. Elevated radon in water may also contribute to elevated radon in indoor air in New Jersey homes. (radata.com)
Why Special Radon Water Testing Matters
Radon in water requires professional testing for accurate assessment. Unlike radon in indoor air — where short-term or long-term test kits can be used — radon in water testing involves:
Certified sample collection procedures (avoiding aeration during collection)
Lab-based analysis using EPA-recognized protocols
Careful interpretation of results with respect to health and air contribution
The ANSI/AARST MW-RN-2020 Standard of Practice outlines the protocols for collecting, transferring, and measuring radon in water samples. This standard is widely recognized by the NRSB and other radon certification bodies and adopted into modern state requirements. (standards.aarst.org)
Homeowners and professionals should ensure that any radon in water sample collection follows these standards to avoid inaccurate results.
New Jersey Certification & Professional Requirements
In 2022, the New Jersey Department of Environmental Protection (NJDEP) updated its radon regulations, adopting ANSI/AARST radon measurement and mitigation standards (including water testing practices) and establishing certification categories for radon professionals. This means:
Radon measurement specialists must be nationally certified
Testing and mitigation businesses must follow state-recognized practices
NJDEP maintains a list of qualified testers and mitigators that meet these standards (aarst.org)
Certified professionals use calibrated equipment and follow established protocols to ensure reliable water testing and mitigation solutions.
How Radon in Water Can Affect Your Home
Radon released from water during normal household use can contribute to elevated indoor air radon levels. Because radon is heavier than air and accumulates in lower parts of the home, the combined effect of soil gas infiltration and radon released from water can elevate health risk if not properly evaluated.
Homebuyers with private well water are strongly encouraged to test both indoor air radon and radon in water before closing, especially in higher-risk areas of New Jersey.
Common Questions About Radon in Water
Does public water mean no radon risk?
Public systems drawing water from surface sources usually have less radon risk. Well water or mixed systems may still contain radon and should be tested.
What level of radon in water is concerning?
There is no enforceable federal MCL, but the EPA has previously proposed 4,000 pCi/L as an action guideline. New Jersey’s recommendation of 800 pCi/L is more conservative. (radata.com)
Is radon in water worse than air?
No. Radon in air presents a greater health risk. Water becomes a concern because it can add to the total radon load inside your home. (US EPA)
Should I treat radon in water?
Treatment is typically recommended when radon in water levels are high or when they significantly contribute to indoor air radon. Aeration or specialized filtration systems are the most effective. Certifying a professional advisor is key to proper system design.
Radon Links
Official Reports on Radon
- EPA Radon Publications
A Citizen’s Guide to Radon (1992). Home Buyer’s and Seller’s Guide to Radon (1993). A Physician’s Guide to Radon (1993). Consumer’s Guide to Radon Reduction (1992). Radon Mitigation Standards (1994). Radon Resistant New Construction. The U.S. EPA
- Health Effects of Exposure to Indoor Radon: BEIR VI (1999)
Summary of the Biological Effects of Ionizing Radiation VI Report. The National Academy of Sciences (1998)
- Residential Radon and Lung Cancer Case-Control Study
The latest and largest-ever epidemiological study on the risks of residential radon. At the EPA “action level” (4 pCi/L), the lung cancer risk to women increases by 50%. U of Iowa (May, 2000)
Sites on Radon, Radiation, and Mitigation
- Radon Mitigation
More information for mitigation.
- How Radon Causes Lung Cancer
“It’s Perfectly Safe, But Don’t Breathe Too Deeply” report on lung cancer risks. Canadian Coalition for Nuclear Responsibility.
- Radon Measurement Methods
A technical comparison of atmospheric radon measurement methods for homeowners and experts. Integrated Environmental Management
- The Health Costs of Man-Made Low-Level Ionizing Radiation
Studies show that radiation from medical procedures has played a role in causing over 50% of cancer deaths and coronary heart disease in the US during the twentieth century. Dr. John Gofman