Radon Explorer · New Jersey
Radon Explorer is an NJDEP-certified New Jersey radon testing and measurement company serving homes, multifamily properties, schools, childcare facilities, and offices statewide.
1 in 8 New Jersey homes has an elevated radon level. Testing is the only way to know yours.1
Stage 01 · Origin
Uranium occurs naturally in rock and soil beneath buildings around the world. Over time, uranium decays through a natural radioactive process.
The green glow is a storytelling device. Uranium in soil does not look like this.
Stage 02 · Decay
As uranium decays, it forms radium. Radium can then decay into radon — a radioactive gas that has no color, smell, or taste.
Each step in the chain happens on its own timescale, from billions of years down to days.
Stage 03 · Movement
Radon gas can travel through openings in soil and enter buildings through differences in air pressure.
The gas shown here is a visual representation. Radon itself is invisible.
Stage 04 · Entry
Radon can enter through cracks, joints, gaps around pipes, sump openings, and other pathways in contact with the ground.
Entry routes vary building to building. No single opening is always the main source.
Stage 05 · Exposure
A building can look completely normal while having an elevated radon concentration. Measurement is the only reliable way to know the level.
People live, sleep, study, and work in a building without any sign that the concentration is high or low.
Stage 06 · Variation
Radon concentrations may vary with weather, ventilation, pressure differences, building conditions, and time. A properly performed measurement helps provide meaningful information about the building.
The day and night cycle above is illustrative. It does not predict hourly radon concentrations in any building.
Uranium occurs naturally in rock and soil. It decays into radium, and radium decays into radon, a colorless, odorless, tasteless radioactive gas. Radon moves through spaces in soil and can be drawn into buildings through pressure differences. It enters through cracks in foundations, floor-to-wall joints, gaps around pipes and utility penetrations, sump openings, construction joints, and crawl spaces. Indoors it mixes with the air people breathe in basements and living spaces. Concentrations change with weather, ventilation, and building conditions. Because radon cannot be sensed, measurement is the only way to know a building's concentration. All animation on this page is illustrative; radon is invisible.
Explore at your own paceTap to learn more about radon
Prefer to click rather than scroll? Choose any point in the building or the ground beneath it.Tap any marker on the house or ground to reveal that part of the radon story.
Select a point
Radon starts in the ground, moves through soil, and can be drawn into the lowest levels of a building before mixing with indoor air. Choose a marker on the cross-section to read about that part of the path.2
Why this matters
Long-term exposure to elevated indoor radon increases the risk of lung cancer. Measurement is how a property owner replaces guesswork with a number.3
The U.S. EPA and the World Health Organization identify radon as a leading cause of lung cancer, and EPA estimates about 21,000 radon-related lung cancer deaths each year in the United States. Risk rises with both concentration and years of exposure.
EPA gives the average indoor radon concentration in U.S. homes as about 1.3 pCi/L, compared with roughly 0.4 pCi/L outdoors. Individual buildings vary widely from these averages.
Exposure is cumulative, so the concentration and the number of hours spent in the building both matter. EPA also notes that radon exposure combined with smoking carries a greater risk than either alone.
Reading a result
Radon in air is reported in picocuries per liter (pCi/L). Move the control to see how published guidance describes a given concentration.4
Drag the marker along the scale, use the slider, or type a measured result — the explanation below updates as you go.
3.2pCi/L
2.7 – 3.9 pCi/L
Below the EPA action level and above the WHO reference level. EPA suggests considering ways to reduce radon between 2.0 and 4.0 pCi/L. A qualified professional can discuss options.
A lower measured concentration. EPA notes there is no known level of radon exposure that carries no risk, so continue following appropriate retesting guidance.
EPA recommends that property owners consider taking action to reduce radon in this range. This band also spans the WHO reference level of 100 Bq/m³, about 2.7 pCi/L.
EPA recommends taking action to reduce radon at or above 4.0 pCi/L (150 Bq/m³). EPA guidance also describes confirming an initial result before mitigating.
Your number determines the next step
Choose the answer that fits. The recommendation changes with your result, so reduction information appears only when it becomes relevant.
01 · Measure
A home’s age, appearance, ZIP code, and the result next door cannot tell you its radon level. A measurement can.
02 · Understand
A result below 4.0 pCi/L is useful information, not the end of the conversation. Because radon changes with seasons and building conditions, a measurement lasting more than 90 days can provide a better estimate of the home’s year-round average.
03 · Confirm, then decide
EPA recommends taking action at or above 4.0 pCi/L and describes confirming an initial result before mitigation. After confirmation, Radon Removal NJ can explain how a system may be tailored to the property and what the reduction process involves.
What we do
Professional radon testing for the places where people live, learn, and work.6
Radon testing and measurement for single-family houses, townhouses, condominiums, and residential transactions where applicable.
Measurement planning for apartment buildings and other multifamily properties, including which units and locations to include.
Professional measurement appropriate for occupied educational and childcare environments, coordinated around the daily schedule.
Radon measurement for offices and other workplace environments where staff spend regular hours.
Eight homes. One unanswered question.
From the sidewalk, all eight homes can look equally ordinary. The one with an elevated level cannot be identified by its age, appearance, ZIP code, or the result next door.
The only home you need to identify is yours.
Could you identify the home by looking?
1 home with an elevated level
among every 8 New Jersey homes in the statewide estimate
They look the same. The measurement is what separates them.
New Jersey service area
Measurement first. Clear information. Informed decisions.
Radon Explorer provides independent radon testing, measurement, and clear reporting throughout New Jersey. We do not sell mitigation systems.
NJDEP certification MET15986
Bergen, Essex, Hudson, Morris, Passaic, Sussex, Union, and Warren
Hunterdon, Mercer, Middlesex, Monmouth, and Somerset
Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester, Ocean, and Salem
How measurement works
You submit the property information, preferred timing, and how you would like us to reply. Nothing is confirmed until you receive a response.
Radon Explorer reviews the building type and measurement requirements, then confirms the scope, timing, and appointment details with you.
The measurement is carried out according to the confirmed plan and the requirements for the property.
You receive the measurement results with an explanation of what the reported concentration means and what published guidance says about it.
Questions
Radon Explorer is an NJDEP-certified company that performs radon testing and measurement for individual properties throughout New Jersey. It is a professional measurement service, not a regional radon map, database, or do-it-yourself detector.
Radon is a naturally occurring radioactive gas produced by the decay of uranium and radium in rock and soil. It has no color, smell, or taste, and it can accumulate indoors.
Because the concentration cannot be sensed or estimated from the outside. Testing is the only way to know whether indoor levels are low or elevated, and long-term exposure to elevated radon increases lung-cancer risk.
No. Age, appearance, construction style, neighborhood, and even a neighbor’s result do not reliably predict a building’s concentration.
Yes. Newer construction can have elevated radon just as older construction can. Some newer buildings include radon-resistant features, but those features still need measurement to confirm the result.
Yes. Soil conditions, foundation type, openings in contact with the ground, and how a building is ventilated all differ between neighboring properties.
Picocuries per liter — a measure of radioactive decay of radon per liter of air. EPA expresses its action level as 4.0 pCi/L; the WHO reference level of 100 Bq/m³ corresponds to roughly 2.7 pCi/L.
The measurement is set up in the agreed locations and completed according to the confirmed plan. We explain what to expect before the appointment.
Preparation depends on the reason for the measurement and the property. We confirm the instructions you need before the appointment.
We confirm any access or occupancy requirements for your property before the measurement begins.
The expected timing depends on the property and the reason for the measurement. We confirm it with the appointment details.
Retesting guidance depends on the previous result, changes to the building, and the reason for the original test. We explain the applicable guidance along with your results.
We explain what the number means and what published guidance recommends. If you decide to pursue mitigation, you choose a qualified mitigation professional; we can point you to reduction resources, and we do not perform that work ourselves.
No. Radon Explorer specializes in radon measurement. It does not install mitigation systems.
Yes. We measure apartment buildings and other multifamily properties and will discuss which units and locations should be included.
Yes. We provide measurement for schools, kindergartens, and childcare facilities, scheduled around occupancy.
Yes. We measure offices and other workplace environments.
Radon Explorer serves all 21 New Jersey counties. Nearby out-of-state requests, including Staten Island and Long Island, may be submitted for individual consideration. Availability is not guaranteed until we confirm applicable requirements, travel logistics, scope, and scheduling.
The one thing to do next
Submit a professional radon measurement request for a U.S. property and choose text, email, or a phone call for our response. New Jersey is our regular service area; every out-of-state request is reviewed individually.
Prefer to email directly? Write to book@radonexplorer.com.
Questions before you book?
For scheduling or questions about a measurement, use the booking request and tell us what you need help with.
New Jersey Radon Hotline: (800) 648-0394. Guidance is periodically updated; verify recommendations against the current source.
Tell us about the property. We’ll confirm the details, availability, and next steps.
