What Health Agencies Know About Radon, the Invisible Gas Found in Homes Across the US & Canada
Radon has no smell and no warning sign. Research links it to thousands of lung cancer deaths every year. Here's what the evidence shows — and the simple tool a growing number of households use to track it.
Radon is one of the most studied indoor air risks in North America. Health agencies in the United States and Canada have tracked it for decades, and their findings line up closely.
The short version is this. Radon is a natural gas that rises from the ground. It can build up inside homes. You cannot see it, smell it, or taste it. And over time, breathing it in is linked to lung cancer.
The research also includes a finding that surprises many homeowners. The same upgrades that make a home more energy efficient can raise the level of radon inside it. A sealed, well-insulated home holds heat better. It can also hold this gas in longer.
That one fact explains a lot. It is why a clean, modern, recently improved home can have a high radon level while the people inside feel completely fine.
What radon is
Radon is a radioactive gas. It forms in the ground as uranium in soil and rock slowly breaks down.4 Almost all soil has some.
Outdoors, radon spreads into the open air and stays very low. It is not a problem outside.
Indoors is different. Radon moves up from the soil and enters a home through cracks in the floor, gaps around pipes, openings in the foundation, and other small spaces. Once inside, a home can trap it, and the level can rise.
The lowest floors usually hold the most. Basements and ground floors sit closest to the source, so readings there tend to be higher.5
What the research says about the health risk
This is where the numbers matter most.
The U.S. Environmental Protection Agency reports that radon is the leading cause of lung cancer among people who never smoked, and the second leading cause overall.1 In Canada, the Canadian Cancer Society calls radon the top cause of lung cancer for people who never smoked.3
One detail shapes how to read this risk. Radon usually causes no symptoms along the way. Agencies note that most people feel nothing until lung cancer is already advanced. The harm builds slowly, over years of breathing high levels.
A high reading is not an emergency. It does not mean a home is unsafe to walk into. It points to a slow, long-term risk that a household would have no way to notice without testing.
The risk is also common. High radon has been found in homes across the United States and Canada — new homes and old, large and small. That is why agencies recommend testing every home.5
Why one home can differ from the next
A common belief is that a neighbor's low result means a nearby home is safe too. The evidence does not support that.
Radon levels depend on the exact ground under a foundation, the openings in a specific home, and how that home moves and holds air. Two houses on the same street can give very different readings.
Why a single test can be misleading
Radon is not a fixed number. Studies show it rises and falls during the day and shifts with the seasons.6
Winter is a clear example. When a home is closed up against the cold, radon often climbs. In colder regions, that can mean months of higher levels in the rooms where families spend the most time.
This affects testing directly. A short test, such as a kit left out for a few days, captures one window of time. It is a useful start. But it can land on a low moment and suggest a home is fine when its true average is higher.
To understand real exposure, the more reliable measure is a long-term average, not one brief reading.6 This is the gap that continuous monitoring is built to fill.
See What Your Home's Air Is Really DoingContinuous radon monitoring →What the evidence points toward: ongoing measurement
The research leads to a clear, practical step. Because radon is invisible, changes over time, and carries a long-term risk, the most useful approach for a household is steady, accurate measurement rather than a single check.
View Radon was built for this. It is a small smart monitor that measures a home's radon level all the time, day and night, in the rooms where people actually live.
Instead of one snapshot, it tracks the level over time and reports a long-term average — the figure most closely tied to real exposure. It does not remove radon, and it does not treat any condition. Its job is narrower and more honest: it turns an invisible, changing risk into a clear number a household can see and follow.
Why accuracy matters here
A reading is only as good as it is accurate, and not every device on the market meets the same standard. Health Canada has warned that some inaccurate radon detectors are sold online.7
View Radon is certified by a recognized radon program that tests devices for accuracy on its own. The result is a reading a household can trust.
When the goal is peace of mind, a reliable number is the whole point. False comfort is the one outcome you don't want.
How it works
Built for long-term monitoring
Radon is an ongoing condition, not a one-weekend event, and the device is built to match. It runs up to 3 years on batteries, with optional USB power, and uses a low-power screen that stays readable without much upkeep. Set it up once, then it works quietly in the background.
For homes that need coverage on more than one level, bundles are available for two floors — so a basement and a main living space can both be watched.
What owners report
"I love that I can glance at the screen and just know. No app, no fuss. The color status makes it simple for the whole family."
"The long-term average data gave us real confidence. Setup over WiFi was a five-minute job."
"Two years on the first batteries and still going. I get a notification if anything changes."
Continuous monitor vs. a one-time kit
A cheap kit's real cost isn't its price. It's the false confidence of one reading, on one day, that may not match the rest of the year.
Common questions
Do new homes really need testing? +
What about homes without a basement? +
Don't my smoke and CO alarms cover this? +
Is it okay to put testing off? +
A measured step toward a safer home
The evidence on radon is consistent across agencies. It is common, it is invisible, it changes over time, and long-term exposure carries a serious health risk. The recommended response is not alarm — it is measurement.
View Radon ships free and is backed by a 60-day money-back guarantee. A household can track its real levels for two months and return the device for a full refund if it isn't the right fit.
Turn an invisible risk into a number you can see
Stop wondering about your home's air. Start tracking it today.
Check My Home's Radon LevelReferences
- U.S. Environmental Protection Agency — "Health Risk of Radon." Radon is responsible for about 21,000 lung cancer deaths a year in the U.S.; it is the leading cause of lung cancer among people who have never smoked and the second leading cause overall. epa.gov/radon/health-risk-radon
- Health Canada — "Radon causes lung cancer." Radon is linked to roughly 3,200 lung cancer deaths a year in Canada, about 16% of all lung cancer deaths. canada.ca
- Canadian Cancer Society — "Radon." Radon is the leading cause of lung cancer in people who do not smoke. cancer.ca
- U.S. EPA — "Radionuclide Basics: Radon." Radon is a naturally occurring radioactive gas produced as uranium in soil and rock breaks down. epa.gov/radiation/radionuclide-basics-radon
- U.S. EPA — "A Citizen's Guide to Radon." Radon enters through cracks and openings in the foundation and accumulates on lower floors; levels vary from home to home; EPA recommends testing every home, including new construction. epa.gov (PDF)
- World Health Organization — "WHO Handbook on Indoor Radon: A Public Health Perspective" (2009). Indoor radon varies by time of day and season; a long-term measurement gives the most representative estimate of exposure. who.int
- Health Canada / Canadian National Radon Proficiency Program (C-NRPP). Consumers are advised to use certified radon measurement devices; some uncertified detectors sold online may give inaccurate results. canada.ca · c-nrpp.ca
Statistics are attributed to the agencies above and reflect their published estimates. Figures are rounded. This page is a paid advertisement and is not affiliated with, or endorsed by, any government health agency.