Radon in Your Home: Why Continuous Monitoring Matters

Alex Navarro 13 November, 2026

When we think about maintaining a healthy home, we usually consider things like changing HVAC filters, controlling humidity, preventing mold, and keeping dust under control. But there's another important part of indoor air quality that often gets overlooked: radon.

Radon is an invisible, odorless gas that could be accumulating in your home without you ever knowing it. Learn why Massachusetts homeowners should take radon seriously, why testing once isn't necessarily enough, and how continuous monitoring can help you better understand your home's indoor air quality. Personally, I have 3 sensors that help me monitor my air quality, radon levels and just generally keep better track of my home's comfort and safety.

Radon is a naturally occurring radioactive gas produced by the breakdown of uranium in soil and rock. It can enter homes through cracks in foundations, floor drains, sump pits, construction joints, and openings around pipes. Once inside, it can accumulate, particularly in basements and lower levels of a home. Here is West Newbury and Amesbury we have relatively high levels of radon so residents like myself really need to be aware of the necesity of monitoring.

According to the Massachusetts Department of Public Health, approximately one in four Massachusetts homes may have radon levels exceeding the EPA's recommended action level of 4.0 picocuries per liter (pCi/L). That's a pretty significant number, especially considering that many homeowners have never tested their homes.

Radon is the second leading cause of lung cancer overall in the United States and the leading cause among people who have never smoked. The EPA estimates that approximately 21,000 lung cancer deaths annually are associated with radon exposure. This is something every homeowner should understand, whether you're buying a home, selling one, or simply maintaining the property you've lived in for years.

Radon Isn't Just a Problem in Certain Neighborhoods

One common misconception is that radon is only a concern in certain geographic areas or older homes. While local geology plays an important role, the actual radon levels inside a home depend on several factors. Soil composition, foundation construction, ventilation, air pressure, weather, and even small openings in a foundation can influence how much radon enters and accumulates indoors.

Two homes on the same street can have dramatically different radon readings. This is particularly important in Massachusetts, where radon has been identified throughout the Commonwealth. The age of your home, whether you have a basement, or whether your neighbor has tested low doesn't tell you what is happening inside your property.

The only way to know is to test your own home. The Massachusetts Department of Public Health recommends that homeowners test their properties regardless of location or foundation type.

You can learn more here: Massachusetts Department of Public Health: Radon Information.

Why a Single Radon Test Isn't Always Enough

Traditional radon testing often involves placing a short-term test kit in a home for a specified period and then sending it to a laboratory for analysis. These tests are useful and remain an important part of home inspections and real estate transactions. However, they provide a snapshot of conditions during the testing period. Radon levels naturally fluctuate, sometimes considerably.

Changes in outdoor temperatures, precipitation, ventilation, heating systems, air pressure, and how a home is being used can all influence indoor radon concentrations. For example, Massachusetts homeowners may see different readings between summer and winter. During colder months, windows and doors remain closed, heating systems operate more frequently, and pressure differences between the house and surrounding soil can influence how radon enters the building.

In fact, Massachusetts recommends testing between November 1 and March 31, when radon levels are typically higher. If you test during the summer and receive a low reading, the state recommends testing again during the winter. A short-term test might capture a period of unusually low readings and give a homeowner a false sense of security. The opposite can also happen, with a temporary spike producing an unusually high result.

This is why I really like the idea of continuous radon monitoring. Rather than relying on one test every few years, a continuously operating monitor gives you an ongoing picture of what's happening inside your home. You can review daily, weekly, monthly, and long-term averages, identify seasonal patterns, and recognize when something changes.

This is particularly useful if your home already has a radon mitigation system. You can keep an eye on whether the system continues to perform as expected rather than waiting until your next scheduled test to discover a potential problem.

The goal isn't to react to every temporary spike. It's to understand the longer-term trend and recognize when something deserves attention.

For more information about radon testing, This Old House has a helpful guide to testing and mitigation.

Airthings: A Better Way to Monitor Your Indoor Air Quality

One company that has made continuous indoor air quality monitoring accessible to homeowners is Airthings. Their monitors use alpha spectrometry to measure radon and continuously collect data that is presented as rolling averages. This is important because radon isn't measured like temperature, where you can get a meaningful instantaneous reading. It takes time to collect enough measurements to establish a representative average.

Airthings makes it easy to view your readings through a display or smartphone app, depending on the model. You can track changes over time, compare different averaging periods, and get a much better understanding of what's happening in your home. Here are three products worth considering.

Airthings View Plus: More Than Just a Radon Monitor

If you're interested in understanding your home's overall indoor air quality, the Airthings View Plus is worth a look. In addition to radon, it monitors several other important indoor environmental factors:

Radon: Tracks long-term exposure to this naturally occurring radioactive gas.
Carbon dioxide (CO2): Helps identify inadequate ventilation and potential indoor air quality issues.
Particulate matter (PM2.5): Measures fine airborne particles from sources like cooking, smoke, and outdoor pollution.
Volatile organic compounds (VOCs): Tracks airborne chemicals that can come from cleaning products, furnishings, paints, and other household materials.
Temperature: Helps monitor indoor comfort.
Relative humidity: Useful for identifying conditions that can contribute to moisture and mold problems.
Air pressure: Provides additional environmental information.

I particularly like this option for homeowners who want to get a better understanding of their entire indoor environment. Radon is an important concern, but CO2, particulate matter, humidity, and VOCs are also worth keeping an eye on. If you're already investing in smart home technology, this is an interesting addition that provides information you otherwise wouldn't have access to.

Checkout the AirThings View Plus Here.

Airthings View Radon: Dedicated Radon Monitoring

If radon is your primary concern, the Airthings View Radon is a more focused option. It continuously monitors radon, temperature, and humidity, with a built-in display and Wi-Fi connectivity. You can view readings remotely through the Airthings app, monitor changes over time, and follow longer-term averages.

The built-in display makes it easy to check readings without opening an app, while Wi-Fi connectivity allows you to keep tabs on your home's radon levels when you're away. This is a particularly good option for a basement or ground floor where radon is most likely to enter the home.

Checkout the Airthings Corentum Here.

Check Out This Crowdsourced Radon Map

Here's something I think every homeowner should take a look at. Airthings has created an interactive Indoor Air Quality Map that displays recent indoor radon readings collected from participating Airthings smart monitors around the world. You can zoom in on different geographic areas and explore actual readings submitted by homeowners.

EXPLORE RADON READINGS IN MASSACHUSETTS

I think this is one of the most interesting resources available to homeowners who want to learn more about radon. You can explore Massachusetts and zoom in on different communities throughout Essex County and the North Shore to see what participating homeowners are measuring inside their properties.

What makes the map particularly interesting is that it demonstrates something important: radon levels can vary significantly between homes, even within the same geographic area. You might see one property reporting relatively low levels while another nearby home has significantly elevated readings. That's a great illustration of why relying on generalized radon maps, geographic risk zones, or your neighbor's test results isn't enough.

Every home needs to be evaluated individually. It's important to understand that this is a crowdsourced map, not a scientific survey of every home in a particular area. The readings come from participating Airthings monitor owners, so the data isn't necessarily representative of the entire housing stock. Homes with existing mitigation systems may also be represented.

It should not be used to predict the radon level in your own home. But that's part of what makes it useful. It provides an interesting, real-world look at what homeowners are actually measuring inside their houses. I'd encourage anyone in Massachusetts, particularly homeowners in Essex County and the surrounding communities, to spend a few minutes exploring the map. You might be surprised by what you find.

What Should You Do If Your Home Has Elevated Radon?

First, don't panic. Elevated radon is a problem that can generally be addressed. The EPA recommends taking action to reduce radon when the average level reaches 4.0 pCi/L or higher. It also recommends considering mitigation when readings fall between 2.0 and 4.0 pCi/L. There is no known completely risk-free level of radon exposure.

If your monitoring device consistently shows elevated readings, consider confirming the results with an appropriate radon test or a qualified radon measurement professional. If mitigation is necessary, the most common solution involves installing an active soil depressurization system.

These systems typically consist of a vent pipe and fan that draw radon from beneath the foundation and safely discharge it outside, preventing it from accumulating inside the home. They can be very effective, but proper installation and follow-up testing are important.

Even after mitigation, continuous monitoring is useful. It gives you another way to keep tabs on the home's indoor environment and recognize if readings begin to rise again. Massachusetts also recommends checking an existing radon mitigation system every year or two to make sure it's operating properly.

A Few Things Every Homeowner Should Remember

Radon can be present in any home, regardless of age, location, or foundation type.
You cannot see, smell, or taste radon.
Approximately one in four Massachusetts homes may have elevated radon levels.
A neighbor's radon results don't tell you what's happening in your home.
Radon levels fluctuate throughout the day and across different seasons.
Long-term averages are generally more useful than isolated readings.
The EPA recommends mitigation at 4.0 pCi/L or higher and consideration of action between 2.0 and 4.0 pCi/L.
Continuous monitoring can help identify changing conditions and provide ongoing insight into your home's air quality.

Final Thoughts

We spend a lot of time maintaining our homes. We change HVAC filters, service heating systems, clean gutters, inspect roofs, and keep an eye out for water intrusion. But how often do we actually think about the air we're breathing? Radon is one of those issues that can go unnoticed for years because there are no obvious signs of a problem. Fortunately, testing is relatively simple, and affordable monitoring options make it easier than ever to stay informed.

Whether you're buying a home, selling one, or simply maintaining the property you've lived in for years, radon deserves some attention. My recommendation is simple: test your home, understand your results, and consider continuous monitoring rather than relying on a single test to tell you everything you need to know. It's a relatively small investment in understanding what's happening inside the place where you and your family spend so much of your time.

Additional resources:

Consumer radon monitors are intended for ongoing residential awareness and should not be assumed to replace professional testing required for real estate transactions. Follow applicable testing protocols and consult a qualified radon professional when appropriate.

Information is Power

Weekly Newsletter

Sign up for our newsletter, stay updated on the local real estate market and learn something new about home ownership, MA real estate regulations and healthier, more efficient homes.

Radon in Your Home: Why Continuous Monitoring Matters

Information is Power

Weekly Newsletter

Radon in Your Home: Why Continuous Monitoring Matters

Getting Your Home Ready for Winter: A Fall Home Maintenance Guide for West Newbury Homeowners

Navigating the Shift: What Late 2026 Real Estate Data Reveals About Essex County and North Shore Communities