Radon Knowledge Base

Additional Radon Monitor Questions

Consumer radon monitors can be helpful, but they often create follow-up questions about averages, alerts, device differences, and what a reading should mean for the home. This page collects additional monitor questions from the knowledge base and keeps the focus on practical interpretation rather than device sales. A monitor can show trends and help a homeowner notice a pattern, but it does not replace understanding the house, the test conditions, or the mitigation system. If readings stay elevated or change after mitigation, Bill can review the mitigation side: fan operation, suction path, crawlspace or sump details, and whether the system needs attention.

What is the difference between Airthings and RadonEye?

The main difference is sensor technology. Airthings Wave-series devices use an alpha spectrometry chip, while RadonEye uses a pulsed ionization chamber. The ionization chamber approach in RadonEye tends to give faster readings - useful if you want early data. Airthings' sensor is well-validated and builds a reliable long-term picture. Both are reasonable choices for homeowner monitoring. For real estate or documentation needs, follow the testing process required for that situation.

Question link

Is RadonEye more accurate than Airthings? (Monitor Comparisons - Expanded)

Both can be accurate for homeowner monitoring when used correctly. RadonEye's pulsed ionization chamber technology is known for fast response and is used in some professional contexts. Airthings' alpha spectrometry approach is well-validated and has been compared to professional monitors in third-party studies. The difference matters less than placement, averaging period, and how you interpret the reading. If you're making a mitigation decision, follow the testing process required for your situation, and call or text Bill if the reading is elevated or confusing.

Question link

What is the difference between a display monitor and an app-only monitor?

A display monitor (like the Airthings View Radon or a SafetySiren) shows current readings on its own screen - no phone needed. An app-only monitor (like the Airthings Wave Radon) stores data internally and syncs to your phone when nearby. Display monitors are easier for users who don't want to manage an app. App-connected monitors give you trend graphs, history, and sometimes remote alerts. The sensor accuracy between these two categories isn't necessarily different - it's about how you prefer to read the data.

Question link

What is the difference between Wi-Fi and Bluetooth radon monitors?

A Bluetooth radon monitor syncs to your phone when the phone is in range - usually within 30-60 feet. A Wi-Fi monitor connects to your home network and can be checked remotely from anywhere. If you want to check radon levels while you're at work or traveling, Wi-Fi is more useful. If you only need to check occasionally when you're home, Bluetooth is usually fine. Some Airthings models use Bluetooth only; others (View series) add Wi-Fi or connect through a hub.

Question link

Airthings vs RadonEye - which should I buy for after mitigation monitoring?

Either works well for post-mitigation monitoring. If you want to check levels remotely from outside the home, consider an Airthings View Radon or a Wi-Fi-connected option. If you want a display in the basement you can glance at, RadonEye's built-in screen is convenient. RadonEye's faster response can help you see changes more quickly after the system starts. For the official post-mitigation test, you'll still need a professional measurement - consumer monitors don't satisfy that requirement in Illinois.

Question link

Is Ecosense more accurate than Airthings?

Ecosense uses an ionization chamber sensor, as does RadonEye. Airthings uses a different sensor approach (alpha spectrometry). Both have been evaluated against professional monitors. No consumer brand is officially rated "more accurate" than another in a universally recognized standard for home use. What matters most is proper placement, sufficient averaging time (at least 7 days for reliable data), and confirmation with a professional test when making decisions.

Question link

Which radon monitor is best for someone without a smartphone?

The SafetySiren is specifically designed for people who don't use smartphones. It plugs into the wall, displays radon levels on its own screen, and sounds an audible alarm if levels rise. Some Airthings View models also have a built-in display but are designed to pair with Wi-Fi. RadonEye has its own built-in display. Any monitor with a built-in display can be used without a phone, though the app models give you historical data you'd miss without syncing.

Question link

Are US-made radon monitors more accurate than Norwegian or Korean ones?

Monitor accuracy depends on the sensor technology, calibration, and testing methodology - not the country of origin. Airthings (Norwegian), RadonEye (South Korean), and Ecosense (US) all have reputable devices. Professional radon monitors used by licensed testers are also made in the US, but that's about their compliance with professional testing standards, not simply where they were manufactured.

Question link

Which radon monitor has the best alarm functionality?

SafetySiren is known for its audible alarm. Several Airthings models can send push notifications to your phone when radon crosses a threshold you set. RadonEye also has alarm settings. If an audible in-home alarm matters - especially for someone who won't have a phone nearby - SafetySiren or similar standalone plug-in monitors are worth considering. App-based notification is only useful if you have the app and notifications enabled.

Question link

Is it worth buying two consumer monitors and comparing them?

It can be useful if you're trying to monitor two areas (basement and first floor, for example) or want a sanity check on a reading. Two monitors in the same spot will sometimes give readings that differ by 20-30% - that's normal and within typical consumer monitor variability. If two monitors in the same room consistently give very different numbers, one may have a failing sensor. For most homeowners, one well-placed monitor is enough.

Question link

Can a consumer radon monitor replace a professional radon test? (Monitor Comparisons - Expanded)

No - not for formal decisions. A professional test conducted by a licensed radon measurement professional under defined protocol is what's required for real estate transactions in Illinois, and it's the appropriate standard for a pre-mitigation baseline. A consumer monitor is ideal for ongoing post-mitigation tracking and year-round trend monitoring. Use professional testing when the decision matters; use a consumer monitor to stay informed between tests.

Question link

What makes RadonEye faster at detecting radon?

RadonEye uses a pulsed ionization chamber, which detects radon decay products with shorter counting intervals than some competing technologies. This allows it to update its displayed reading more frequently. It's genuinely useful for watching how radon responds to changing conditions. Keep in mind that even with faster response, the long-term average is what determines real exposure - a single fast reading doesn't give you the full picture of your home's radon level.

Question link

Which radon monitor works best without any internet connection at all?

SafetySiren operates entirely standalone - no app, no internet, no phone required. RadonEye stores data on the device and displays a reading without internet. Airthings Wave models store readings locally and can sync when a phone is in range later, even without internet at the time of recording. If you have no smartphone and no internet, SafetySiren is the simplest option.

Question link

What does NRPP or C-NRPP certification mean for a radon device?

NRPP (National Radon Proficiency Program) and C-NRPP (Canadian equivalent) certify the people and companies performing radon measurements - not the devices themselves in the consumer market. Professional measurement devices used by licensed radon testers must meet specific requirements, but this certification program applies to the professional, not the Airthings or RadonEye you buy at retail. Consumer monitors aren't licensed under NRPP for use in formal real estate tests.

Question link

Is one monitor enough for a whole house?

For general monitoring, yes - place it in the lowest regularly occupied area (usually the basement) to track the highest-risk zone. If you also spend significant time on the main floor or in a first-floor room that's at or near grade, a second monitor there can give you a fuller picture. After mitigation, one monitor in the basement where the system is installed is typically sufficient for long-term tracking.

Question link

Which radon monitor is best for a crawlspace home?

For a home with a crawlspace instead of a basement, test on the first floor in the lowest regularly occupied space. Place the monitor on the first floor, away from exterior walls and vents. You can also place a monitor near the crawlspace access opening to see levels in that area, though that reading won't represent the breathing zone upstairs. The key is understanding that radon from the crawlspace can still enter the living space above.

Question link

Which monitor has the longest warranty?

Warranty terms vary by manufacturer and change over time - check the current manufacturer page for the specific model you're buying. Most consumer radon monitors carry a 1-2 year limited warranty. Warranty length should be a secondary factor; sensor quality, placement guidance, and app usability matter more for practical use.

Question link

Does temperature affect radon monitor accuracy?

Temperature can affect electronic sensors, and most consumer monitors have an operating temperature range specified in their documentation. Extreme cold (below freezing) in an unheated garage or crawlspace can affect accuracy. Very high humidity can also affect some sensors. For normal basement conditions - even cold basements in winter - most consumer monitors operate within acceptable ranges. Check the manufacturer's spec sheet for your specific model.

Question link

Do professionals use Airthings or RadonEye to verify mitigation results?

Some professionals do use consumer monitors like RadonEye as a quick field check, but this is not the same as a formal post-mitigation test. In Illinois, the post-mitigation test must be conducted by an independent licensed radon measurement professional using calibrated equipment. A RadonEye or Airthings reading after installation can give the installer a quick indication of whether the system is working - but it doesn't satisfy the state testing requirement.

Question link

If I have both a RadonEye and an Airthings and they disagree, which one should I trust?

Neither monitor is necessarily wrong when they disagree. Consumer monitors naturally vary due to differences in sensor technology, placement height differences (even a few inches matter), and sample timing. If both are in the same room and the disagreement is more than 30-40%, check placement and make sure both have been running long enough to have a meaningful average. If one monitor is new and one is older, the older one may have drifted. For a definitive answer, get a professional test.

Question link

Can I share my radon monitor data with my insurance company?

Some insurance companies have started asking about radon or offering discounts for mitigated homes. What they accept varies by insurer. A consumer monitor reading is informal - a professional post-mitigation test report from a licensed tester carries more weight for any formal purpose. Check directly with your insurer what documentation they want.

Question link

Does any consumer monitor meet AARST or NRPP testing standards for real estate?

No consumer monitor currently meets the standards for conducting a formal real estate radon test that would satisfy licensing requirements. AARST and NRPP standards for real estate testing require professional-grade devices, calibration documentation, chain of custody, and a licensed professional conducting and interpreting the test. Consumer monitors serve a different, valuable purpose - ongoing monitoring - but they're not a substitute for a licensed test at the point of sale.

Question link

What is the difference between the Airthings Wave Radon and the Wave Plus?

The Wave Radon measures only radon. The Wave Plus adds CO2, VOC (volatile organic compounds), temperature, humidity, and atmospheric pressure. Both use the same Bluetooth connection and sync to the same Airthings app. If you primarily want radon monitoring, the Wave Radon is the focused option. The Wave Plus is useful if you want a broader indoor air quality picture from the same device.

Question link

Does the Airthings Wave Radon require Wi-Fi?

No. The Wave Radon uses Bluetooth only. It stores readings internally and syncs to your phone when the phone comes within Bluetooth range. You don't need home Wi-Fi for it to work - just the Airthings app on your phone. If you want to check radon levels remotely (without being home), you'd need an Airthings Hub or a Wi-Fi-connected Airthings device.

Question link

What is the Airthings Hub and do I need one? (Monitor App, Wi-Fi, Battery, and Setup - Expanded)

The Airthings Hub connects to your home Wi-Fi and allows Bluetooth Airthings Wave devices to report data to the cloud without you needing to bring your phone near the device. This means you can check readings remotely from anywhere. You don't need a Hub for the device to work locally - but you do need it for remote access with Wave-series devices. View-series Airthings devices connect directly to Wi-Fi without needing a Hub.

Question link

How do I set up the Airthings Corentium Home 2?

The Corentium Home 2 doesn't require Wi-Fi or a smartphone to function. Install the batteries, let it run for 24 hours to begin calibrating, and it will display readings directly on its USB-connected interface. You can plug it into a computer to download data using Airthings' desktop software. For detailed setup steps, follow the current Airthings documentation at their support page or the quick start guide that comes in the box.

Question link

Can I use Airthings without creating an account?

The Wave-series Airthings devices require the app to view historical data, and the app requires an account. The Corentium Home can display readings standalone without an account if you read it directly via USB and desktop software. Check Airthings' current account requirements on their website - these details can change with app updates.

Question link

My Airthings app says the device is offline. What does that mean?

If you have a Bluetooth-only device (Wave Radon, Wave Plus), it appears "online" in the app only when your phone is in Bluetooth range. If the phone hasn't been near the device recently, the app shows the last synced data and may show the device as offline. This is normal - the device is still recording internally. Bring your phone near the device to sync. If you have a Wi-Fi-connected device or Hub, an "offline" message may mean the Hub lost its internet connection.

Question link

Can I use Airthings without a smartphone?

The Corentium Home models can be used without a smartphone - they display readings on a built-in display or via USB/desktop software. The Wave-series devices technically work without a phone (they record internally), but you can't view the data without the app. For smartphone-free use, the View Radon (which has its own display) or a non-app monitor like SafetySiren are better fits.

Question link

How long do Airthings Wave Radon batteries last?

Battery life varies depending on how often the device syncs with your phone. Airthings generally estimates the Wave Radon battery lasts around 12-16 months under typical use, but this is approximate and depends on sync frequency and battery brand. When the battery is low, the app will notify you. Use quality AA batteries - cheap batteries can shorten life significantly.

Question link

Can I plug in the Airthings Wave instead of using batteries?

The Airthings Wave Radon and Wave Plus are designed to run on batteries only. There is no official power adapter port for these models. The Airthings View Radon plugs into a USB-C power supply. Check the specific model you own - the product line has expanded and power options differ by model.

Question link

Does Airthings store data when the batteries die?

The device stops recording when power is lost. When you replace the batteries, most models resume from a fresh start rather than recovering prior data. Historical data synced to the app before the batteries died is preserved in the cloud. Check Airthings' current documentation for the specific behavior of your model, as this has varied between firmware versions.

Question link

How do I set up radon alerts in the Airthings app?

Open the Airthings app, select your device, and look for notification or alert settings. You can typically set a threshold (such as 4.0 pCi/L) and the app will send a push notification if your reading crosses it. Make sure notifications are enabled both in the Airthings app and in your phone's notification settings. Alert delivery also requires the device to sync data to the app, which for Bluetooth devices means your phone needs to be in range periodically.

Question link

Can Airthings notify family members about my radon level?

Airthings allows you to share device access with other accounts. Family members can add your device to their Airthings app and view the same readings. Whether they receive alerts depends on their notification settings. This is useful for adult children checking on an elderly parent's home, for example.

Question link

Does Airthings work with Google Home or Alexa?

Airthings has offered integrations with Google Home and Amazon Alexa in some versions of their platform. Integration availability can change with app updates. Check the current Airthings integrations page or the Google Home/Alexa skill store for current status. Voice assistant integrations typically let you ask for the current radon level verbally.

Question link

Can Alexa or Google tell me my radon level?

If your Airthings device is connected to your account and you have the Airthings skill or integration active in Alexa or Google Home, you can ask for the current reading. This requires a Wi-Fi-connected Airthings device or Hub so data is available in the cloud. The availability and accuracy of these integrations can change - check Airthings' current documentation.

Question link

What is the Airthings View Radon? (Monitor App, Wi-Fi, Battery, and Setup - Expanded)

The Airthings View Radon is a radon monitor with a built-in color display that shows current readings without needing a phone. It connects to your home Wi-Fi directly (no Hub required) and allows remote access through the app. It's a good choice if you want a display in the basement and the ability to check from anywhere.

Question link

What is the Airthings View Plus?

The View Plus is similar to the View Radon but adds additional sensors (CO2, VOC, temperature, humidity, light, noise in some versions). It's Airthings' most comprehensive home air quality monitor. If you want radon plus a broader air quality picture on one screen, the View Plus covers both.

Question link

My Airthings device keeps disconnecting from the app. What's wrong?

For Bluetooth devices, disconnection is normal when your phone moves out of range - the device is just not syncing, but still recording. If your phone is nearby and still not syncing, try: restarting the app, toggling Bluetooth off and on, ensuring the device has enough battery, and checking for app updates. For Wi-Fi devices, check your router connection and that the device is within Wi-Fi range.

Question link

How long does Airthings keep historical data? (Monitor App, Wi-Fi, Battery, and Setup - Expanded)

Airthings stores historical data in the cloud for accounts with an active subscription or within the free tier's limits. The specific retention period for the free tier is something to verify on Airthings' current pricing page - these terms can change. Data synced to the device internally before a battery failure is typically not recoverable. For long-term tracking, sync frequently and check whether your account tier retains full history.

Question link

Can I export my Airthings radon data?

Yes - Airthings allows data export from the app or dashboard. The format is typically a CSV file with time-stamped readings. This is useful if you want to create your own graphs, share data with a professional, or keep your own records. Check the Airthings app or dashboard for the current export option location.

Question link

Does the Airthings Wave work if I don't have a smartphone?

The Wave Radon and Wave Plus work without a smartphone in the sense that they record data internally. But you can't view that data without the app. If you don't use a smartphone, consider the Airthings View Radon (built-in display) or a monitor like SafetySiren that doesn't require any connected device.

Question link

My Airthings shows 0.0 pCi/L. Is that possible?

A reading at or near zero is possible in some homes, especially with good ventilation or an active mitigation system. It can also indicate a sensor issue, particularly if the device is brand new and still calibrating (the first 24-48 hours are often not representative). If the device has been running for several days and consistently shows 0.0, check placement and consider whether it may need support from Airthings.

Question link

How do I set up the Ecosense EcoQube?

Setup instructions vary by model - consult the current Ecosense documentation that comes with the device or is available on their website. Generally, you install batteries or plug in the device, download the Ecosense app, pair via Bluetooth, and allow 24 hours for initial calibration. Specific steps for the EcoQube Flex vs the standard EcoQube differ - use the guide specific to your model.

Question link

What is the Ecosense EcoBlu?

The EcoBlu is an Ecosense product designed for professional and real estate testing contexts, offering faster and more precise readings than typical consumer models. It's positioned between consumer monitors and full professional continuous radon monitors (CRMs). If you've seen this referenced by an inspector or professional, it may be what they're using rather than the consumer EcoQube.

Question link

Does the RadonEye Plus have an app?

RadonEye Plus models (such as RD200+ variants) support a companion app that displays readings on your phone and may allow data logging and export. The original RD200 also connects via Bluetooth to a phone for data viewing. App features and availability can change - check the current RadonEye app page for your model. Some users find RadonEye's app simpler than Airthings'; others prefer the Airthings ecosystem.

Question link

Can I use the RadonEye without its app?

Yes - the RadonEye has a built-in display that shows the current reading without needing a phone or app. The display is one of RadonEye's advantages for users who want a glanceable reading in the basement without pulling out a phone. The app adds historical graphs and data export functionality.

Question link

What batteries does the RadonEye use?

RadonEye models use different battery types depending on the version. Most common is 3 AA batteries. Check the documentation for your specific model. Battery life varies by model and usage - consult the manufacturer's current spec sheet for expected duration.

Question link

Can the RadonEye be plugged into wall power?

Some RadonEye models support AC power through a USB connection or adapter. Check the specific model documentation. Not all RadonEye versions support continuous wall power, and using the wrong power method can void warranty. For permanent basement monitoring, some users leave the RadonEye on a USB power bank to avoid battery swaps.

Question link

How do I interpret the RadonEye display?

The RadonEye display typically shows the current (short-term) reading and may also show a longer-term average. The reading is in pCi/L. The current reading updates frequently - the pulsed ionization chamber allows faster updates than many competing monitors. A single high reading on the display doesn't necessarily mean your home has a permanent problem - look at the trend over days and weeks for meaningful data.

Question link

Does the RadonEye alarm if radon is high?

Yes - RadonEye has an alarm function that activates when radon exceeds a threshold. The exact threshold and alarm behavior vary by model. Some models allow you to set the threshold in the app; others use a fixed default. Consult the current RadonEye documentation for your specific model for alarm configuration.

Question link

What is SafetySiren and who makes it?

SafetySiren is a brand of standalone plug-in radon detector made by Family Safety Products. It's designed to be simple - plug it in, let it warm up and calibrate, and it will display readings and alarm audibly if radon is elevated. There is no app. This makes it well-suited for people who want a simple, dedicated radon detector without technology complexity.

Question link

Does SafetySiren have a battery backup?

Some SafetySiren models include a battery backup for continued operation during a power outage. This is noted as a feature of higher-end Pro models. Verify the current model's features on the manufacturer's page - not all SafetySiren versions include battery backup.

Question link

My SafetySiren is alarming. What do I do?

If your SafetySiren is alarming, first note what it's displaying - the reading will tell you how elevated the radon is. Open some windows temporarily to see if the reading drops (this confirms the sensor is responding to actual radon, not a false trigger). If the alarm continues at elevated levels after a day of normal conditions, call or text Bill or fill out the form on our website so we can help you understand what the reading means and whether mitigation makes sense.

Question link

My Ecosense EcoQube reading dropped sharply overnight. Is that accurate?

Sharp overnight drops can happen - particularly if ventilation changed, a door was left open, or outdoor conditions shifted barometric pressure significantly. One night's drop in isolation is less meaningful than the multi-day trend. If your Ecosense has been running for a week or more and shows a consistent average well below 4.0 pCi/L, a single overnight low doesn't change that picture. If you see unpredictable swings that don't seem tied to anything, let the device run another 7-14 days and look at the overall trend.

Question link

My Ecosense app shows a "Good" air quality status at 3.9 pCi/L. Does that mean I don't need to do anything?

"Good" in the app's color-coded system reflects their internal threshold display - it doesn't mean the EPA would say no action is warranted. The EPA says to consider mitigation between 2.0 and 4.0 pCi/L, particularly with consistent readings in that range and factors like young children, frequent basement use, or smokers in the home. If you're consistently at 3.9 and you spend meaningful time in that space, it's worth a conversation. Call or text Bill and we can help you think through whether mitigation makes sense for your situation.

Question link

My Airthings short-term average is 5.5 pCi/L but the long-term average is 2.8 pCi/L. Which matters more?

The long-term average is more meaningful for understanding your real radon exposure. Short-term averages (24 hours or 7 days) can fluctuate significantly based on weather, pressure, and ventilation. A long-term average built over 30-90 days represents what you're actually breathing over time. If your long-term average is 2.8 and your recent short-term spiked, that spike is worth watching - but it doesn't override 30+ days of data showing 2.8.

Question link

My Airthings reading was fine for 6 months and then jumped last week. What changed?

Sudden changes after months of stability are worth paying attention to. Common causes: a window or door being left open differently, HVAC changes (fan speed, filters, new ducts), foundation changes (new cracks, settling after dry or wet seasons), or a change in how much time the space is occupied. If it jumped and stayed high for more than a week without an obvious explanation, that's worth investigating. Give us a call if you'd like help thinking through what might have changed.

Question link

My Airthings reading went up when I installed a new sump pump. Is that connected?

Possibly. Sump pits are a common radon entry point. If your new sump pump disturbed soil or left an unsealed pit opening, it could allow more radon to enter. Make sure the sump pit lid is sealed - gaskets and sealed covers are a common first step before full mitigation. If the reading stays elevated, that may confirm the sump pit is a significant entry point and a mitigation system would address it directly.

Question link

My Ecosense EcoQube shows different readings at different times of day. Is that normal?

Yes - radon levels naturally vary throughout the day and night. Common patterns include lower readings during the day when doors and windows may be open more, and higher readings at night or early morning when the house is closed and barometric pressure is lowest. This is expected behavior, not a device fault. The long-term average from your Ecosense is more useful than any single time-of-day reading.

Question link

My Airthings reading has been exactly the same for 3 days. Is it frozen?

If the reading has been literally identical down to the decimal for multiple days, the device may have lost connectivity or experienced a glitch. Try syncing your phone with the device, check for app updates, and verify the device has power. In some cases, very stable conditions can produce very stable readings - but three days of exactly identical numbers is worth investigating. Restart the device if it allows it, or contact Airthings support.

Question link

My Airthings data disappeared. Where did it go?

If you've logged out of your Airthings account or the device was reset, local and cloud history may appear missing. Try logging back in on a different device to see if cloud data is still there. If the device's batteries died, readings stored only on the device (not yet synced) may be lost. Contact Airthings support if you believe data should be in your account but isn't showing up.

Question link

I ran my whole-house fan for a day and my Airthings dropped significantly. Does that mean the fan fixes the problem?

A whole-house fan creates significant negative pressure and draws air through the house - that can temporarily dilute radon by pulling in outside air. But this doesn't address the source. When the fan isn't running, radon levels typically return. A mitigation system works differently: it creates sub-slab depressurization that redirects soil gases away before they enter the house. Ventilation is a temporary measure; mitigation is a lasting solution. If you want to test this further, let the reading return to baseline after stopping the fan and compare.

Question link

My Airthings is in the basement at 3.5 pCi/L and my neighbor's house shows 1.0. We live next door. How can there be that much difference?

Radon variability between neighboring homes is completely normal - in fact, it's expected. Radon levels depend on the specific geology under each home, the foundation type, the number and size of cracks or openings in the foundation, sump pit conditions, and how air moves through each house. Two identical houses on the same block can have very different radon levels. Your 3.5 pCi/L is specific to your home and your situation.

Question link

My Ecosense reading is different from a charcoal test I mailed to a lab. Which is right?

Both can be accurate but measure slightly differently. A charcoal canister test captures an average over its test period (typically 48-96 hours) under closed-building conditions with specific protocol requirements. Your Ecosense continuously monitors under real-world conditions. Differences are expected - particularly if the charcoal test was done with closed windows that you don't normally maintain, or if conditions were different on those days. If both are in the same general range (within 30-40%), they're telling a consistent story. If they differ dramatically, a professional test with full protocol documentation will give you the most defensible number.

Question link

After my radon mitigation system was installed, my Airthings jumped briefly before dropping. What happened?

This is actually fairly common. When installers cut into the slab to create the sub-slab suction point, they may temporarily stir up soil gases. Radon can briefly increase before the fan establishes suction and begins depressurizing below the slab. Within 24-48 hours, the system should begin pulling radon down and your monitor should start dropping. If levels remain elevated after 48-72 hours, contact your installer.

Question link

My Airthings long-term average just hit 4.0 pCi/L for the first time. What should I do now?

At 4.0 pCi/L, the EPA recommends fixing the home. This isn't a panic situation, but it's time to act. The good news is mitigation is straightforward. Give us a call or fill out the form on the website and we can walk you through what's involved - it's typically a one-day installation and the system runs continuously after that.

Question link

My Airthings shows a different reading from morning to night. Should I use the morning or evening reading?

Neither single reading is more correct than the other. Radon naturally varies throughout the day - often lower in the afternoon (more activity, more air exchange) and higher in the early morning (house closed overnight, low pressure). This is why the long-term average, not a point-in-time reading, is what you should use when deciding whether to mitigate. Let the device run for at least 30 days and watch the long-term trend.

Question link

I have a crawlspace under my first floor. Where do I put the radon monitor?

For a home with a crawlspace and no basement, test on the first floor - the lowest occupied level of the home. Place the monitor in the most-used room on the first floor, at breathing-zone height (around 3-5 feet off the floor), away from exterior walls and vents. The crawlspace itself is not where you'd normally place a monitor for living-space measurement. If you want to understand whether the crawlspace is a radon source, a professional can assess that as part of a mitigation evaluation.

Question link

Can I put a radon monitor inside a sealed crawlspace?

Technically yes, but for understanding your living-area radon exposure, that reading won't directly represent what you're breathing. Crawlspace radon concentrations can be very high but vary depending on ventilation - measuring there tells you about the source, not your personal exposure. For personal exposure, measure in the occupied first-floor rooms. For a mitigation assessment, a professional will evaluate the crawlspace directly.

Question link

My house is on a slab. Does radon still get in?

Yes. Radon can enter through cracks in the slab, expansion joints, pipe penetrations, and any opening between the soil and the interior. Slab homes often have different radon dynamics than basement homes but they're not inherently lower risk. The way to know is to test. Place a monitor on the first floor (the lowest occupied level) in a regularly used room.

Question link

Where do I put a radon monitor in a ranch house with no basement?

On the first and only floor, in the lowest regularly used room - often a main living area or bedroom. Avoid kitchens, bathrooms, and rooms near exterior doors that are frequently opened. The breathing zone (3-5 feet off the floor) is the target placement height.

Question link

Where do I test in a split-level home?

Test on the lowest occupied level - typically the lowest split-level floor that contains a bedroom or living area. In many split-level homes this is a lower family room or bedroom level that's partially below grade. If the lowest level is only storage or utility space that nobody occupies, test the next lowest occupied level.

Question link

Can I put a radon monitor in a finished basement with carpet?

Yes. Carpet doesn't affect monitor accuracy in any meaningful way. Place the monitor on a shelf, table, or furniture surface at breathing-zone height (roughly 3-5 feet off the floor). Don't place it on the floor itself regardless of the surface type - floor-level readings don't represent the breathing zone.

Question link

My basement has a drop ceiling. Should the monitor be above or below the tiles?

Below the tiles, in the living space. The drop ceiling creates a different air volume above it - measurements there don't represent the air in the occupied room below. Place the monitor at breathing-zone height in the occupied basement space.

Question link

Can I put a radon monitor in a laundry room?

A laundry room in the basement is generally not the best placement unless it's the only accessible basement area. Dryers exhaust air and washers can increase humidity - both can temporarily affect readings. If the laundry room is the main basement space, it's usable; just keep the monitor away from the dryer vent. A general living area or spare room in the basement is a more representative placement if available.

Question link

My basement has a sump pit with a cracked plastic lid. Could that affect my monitor reading?

Yes - an unsealed or cracked sump pit lid is a common radon entry point. The sump pit connects to soil below the slab, and if it's not sealed, soil gases (including radon) can enter directly through it. It's worth sealing the lid properly regardless of your radon level. If your reading is elevated, the sump pit is one of the first things worth addressing.

Question link

Where should I put the monitor in an unfinished basement with exposed pipes and ductwork?

Choose a spot away from the HVAC equipment, sump pit, and floor drains. A clear wall at breathing-zone height in an area where air circulates freely is the goal. Don't place it directly next to a large air handler or next to where the furnace exhausts. The center of the basement space, at about 3-5 feet off the floor, is generally a good starting point.

Question link

I have two basements - a finished part and a mechanical room. Do I need to test both?

One monitor in the finished, occupied area is the priority - that's where people spend time. If you're curious about the mechanical room, you can place the monitor there briefly, but the finished living area is what matters for exposure purposes. If you're doing a formal test for real estate or mitigation planning, test in the finished area.

Question link

My basement has a walkout door on one side. Does that side have lower radon?

Possibly - a walkout side with more above-grade exposure may have somewhat better natural ventilation. But radon entry is primarily through the floor and foundation walls, and it can enter equally on all sides. Don't assume the walkout side is lower without testing. Radon distributes through the basement air and averages out across the space.

Question link

Can I move my radon monitor to different rooms to get different readings?

You can, but wait at least 7 days after moving it before trusting the new location's reading - it takes time to establish a meaningful average in a new location. Moving it frequently will give you short-term snapshots that aren't as reliable as letting it run in one spot. If you want to understand multiple rooms, consider a second monitor rather than constantly relocating one.

Question link

I have a finished basement with a home office. Where should the monitor be relative to my desk?

Somewhere in the room at breathing-zone height - near your desk is fine. You want it in the area where you spend the most time. Don't put it directly on the desk under your monitor if there's airflow from equipment; a nearby shelf or side table is better. The goal is to measure what you're breathing during the hours you're working there.

Question link

My teenager's bedroom is in the basement. Should the monitor be in their room or in the common basement area?

If your teenager spends significant hours in that bedroom, that room is the most important spot to measure. They're breathing that air while sleeping - often 8+ hours a night. Place the monitor in their bedroom at breathing-zone height away from windows and exterior walls.

Question link

I run a home daycare in my basement. Where should the radon monitor go?

Place it in the main area where children spend their time - at breathing-zone height for an adult (3-5 feet), which will still be representative of the children's breathing zone, though children breathe closer to the floor. If the reading is at or above 2.0 pCi/L in a space where young children spend many hours weekly, that's worth taking seriously. Children breathe more air relative to their body size than adults, so their exposure per pCi/L is proportionally higher.

Question link

My basement floods occasionally. Does that affect where I put the monitor?

Keep the monitor elevated enough that it won't be submerged if the basement floods. After a flooding event, radon readings may change - water saturating the soil changes how gases move through it. Let things dry out and stabilize before relying on post-flood readings as your baseline. If you're dealing with recurring water intrusion along with elevated radon, a mitigation system addresses both issues in different ways - it's worth a call to discuss your situation.

Question link

I have a finished basement with multiple rooms - a family room, a guest room, and a storage room. Is one monitor enough?

One monitor in the most-used area (usually the family room or the bedroom if someone sleeps there) is typically enough to understand your exposure. If you want a complete picture, a second monitor in the guest bedroom adds useful data. The storage room doesn't need monitoring unless someone spends meaningful time there.

Question link

Can I put a radon monitor in my detached garage?

A detached garage is not a typical testing location because it's not an occupied living space. If your garage is attached to the house and has interior access, you might want to test whether radon from the garage area affects living spaces - but the better measurement is still inside the house, in the lowest occupied room. A garage with no habitable connection to the house doesn't need a consumer radon monitor.

Question link

My basement has a wood stove. Does that affect where I put the monitor?

Yes - keep the monitor away from the wood stove. Combustion affects air chemistry and can pull outside air into the basement when the stove is running. Place the monitor at the opposite side of the basement from the stove, away from the chimney or stovepipe, and at breathing-zone height.

Question link

How long should my consumer monitor run before I trust the post-mitigation reading?

At least 7 days after the fan has been continuously running, and ideally 30 days for a stable long-term average. The first 24-48 hours after installation can be misleading as the system establishes sub-slab pressure equilibrium. By day 7, you should see a clear downward trend if the system is working. Your official Illinois post-mitigation test (by a licensed professional) should be conducted according to state timing requirements - not just when your consumer monitor looks good.

Question link

My monitor went UP the first day after the mitigation system was installed. Is that normal?

Yes, this happens. The installation process involves cutting into the slab and possibly disturbing subslab soil, which can temporarily release concentrated soil gas. Once the fan establishes suction and pulls the pressure below the slab negative, radon entry should be reduced and the consumer monitor should begin showing a decline within 24-72 hours. Contact your installer if the reading doesn't begin declining after 72 hours.

Question link

My post-mitigation reading is 2.5 pCi/L on my consumer monitor. Is the system underperforming?

Not necessarily. Post-mitigation results vary significantly by home. Some homes drop to 0.5 or below; others settle around 1.5-2.5. A result at 2.5 pCi/L is below the EPA action level of 4.0 pCi/L - that's a meaningful improvement if you started higher. If you started at 4.0 and ended at 2.5, the system worked. If you started at 10 pCi/L and are at 2.5, that's an excellent result. The professional post-mitigation test will give you the documented number.

Question link

Do seasonal swings affect post-mitigation readings?

Yes - even homes with mitigation systems see some seasonal variation. Winter typically brings slightly higher readings because homes are sealed tightly. The system actively counteracts this, but some variation is normal. Your annual professional re-test will capture a snapshot; a continuous consumer monitor lets you see the seasonal pattern over time.

Question link

My mitigation fan is getting louder. Does that mean it's working harder or failing?

A change in fan noise can be a sign of fan wear. Radon fans have a service life, typically 10-20 years depending on the model and conditions. A louder fan isn't necessarily failing immediately, but it's worth having checked - particularly if the noise change is accompanied by a rise in your consumer monitor reading. Call us if you notice both a noise change and a reading increase.

Question link

I have two consumer monitors in my basement post-mitigation and they give different readings. Which one is correct?

Two monitors in the same room can legitimately differ by 20-30% - this is within normal consumer monitor variability. If the difference is larger (one says 0.5 pCi/L, the other says 2.5 pCi/L), check whether they're in the same location, at the same height, and whether one may have a failing sensor. Average the two readings as a rough guide, and get a professional test for the definitive number.

Question link

My mitigation system has been running 5 years. Do I need a professional retest?

The EPA recommends retesting every 2 years after mitigation. Five years is overdue for a professional retest. Your consumer monitor may show a good reading, but professional documentation is valuable - particularly if you ever sell the home. Give us a call if you'd like help arranging a post-mitigation retest.

Question link

Does my radon system warranty cover a new professional test if radon comes back?

Warranty terms vary by contractor. Most mitigation warranties cover the installed system itself (fan, piping, workmanship) but don't necessarily include re-testing costs. Ask your original installer what their warranty covers. If you're working with us, we can clarify what our warranty terms include. Give us a call.

Question link

My consumer monitor says 0.4 pCi/L post-mitigation. Do I still need the professional test?

Yes - in Illinois, the post-mitigation test must be conducted by an independent licensed radon measurement professional. Your consumer monitor reading at 0.4 pCi/L is a good sign that the system is working well, but it doesn't satisfy the state's documentation requirement. The professional test provides a written report you can keep on file and reference if you sell the home.

Question link

My mitigation system was installed 3 years ago. I never did the post-mitigation professional test. Is it too late?

It's never too late to get a post-mitigation test, and I'd encourage you to get one. A current professional test gives you documented confirmation of what your system is doing today. After 3 years, conditions may have changed slightly (fan wear, seasonal settling, foundation changes). A current professional test is worth having. Give us a call and we can help you arrange one.

Question link

My Airthings dropped from 6.0 to 0.9 pCi/L after mitigation. Is that real?

That's a very plausible result for a successful mitigation installation. Radon can drop quickly once sub-slab depressurization is established - sometimes within 24-48 hours. 0.9 pCi/L is well below the EPA action level and represents a strong outcome. Confirm this with the professional post-mitigation test, which gives you the documented result for your records.

Question link

My manometer gauge shows almost no difference. Is my fan working?

A manometer (also called a U-tube gauge) shows the pressure difference the fan is creating between the suction pipe and indoor air. If both sides are nearly equal, the fan may not be pulling adequate suction - or the gauge may not be reading correctly. Check that both ends of the gauge are properly connected. If the gauge is flat and your consumer monitor reading has risen, contact your installer - the fan may have failed or the suction point may be obstructed.

Question link

Can I test in my house while the mitigation system is still new?

You can - your consumer monitor provides ongoing information. But for the official Illinois post-mitigation test, follow your installer's guidance on timing. Testing too early (before the system has had time to establish consistent suction) may not represent steady-state performance. Most guidelines suggest waiting 24-30 days minimum before the professional post-mitigation test.

Question link

I bought a house with a mitigation system already installed. There's no post-mitigation test report. What do I need?

Get a current professional test conducted by a licensed measurement professional. This gives you a documented baseline and confirms whether the existing system is currently working. Contact the original installer if possible to get any documentation they have. If you don't know who installed it, a professional tester can assess the system's current condition as part of a full evaluation. Give us a call if you'd like help with this.

Question link

I've been using a consumer monitor for 6 months post-mitigation and it consistently shows 1.1 pCi/L. Do I need a professional retest?

If it's been within 2 years of installation and you're within the state's timing requirements, you should get the official professional test to document your result. Your consistent 1.1 pCi/L is a strong sign the system is working well, which should be confirmed with professional documentation. After that, the EPA recommends re-testing every 2 years.

Question link

What is SafetySiren and who is it best for?

SafetySiren is a standalone plug-in radon detector that doesn't require a smartphone, app, or Wi-Fi connection. It has a built-in display and sounds an audible alarm if radon rises above an elevated threshold. It's particularly well-suited for people who want a simple, dedicated device they can plug in and monitor without managing an app - elderly homeowners, vacation homes, or anyone who wants a no-tech radon indicator in their basement.

Question link

Does SafetySiren have a smartphone app?

No. SafetySiren is specifically designed without an app or internet connection. It operates as a standalone device. This is its primary advantage for users who don't want app complexity, and its primary limitation for users who want remote access or historical graphs.

Question link

My SafetySiren is beeping. What does that mean?

A SafetySiren alarm indicates that radon has risen above the device's alert threshold. The reading on the display will tell you the current level. Open windows temporarily to see if the reading drops - this can confirm the sensor is responding to actual radon. If the reading is elevated and returns when the windows are closed, that's a sign your home may need a professional mitigation evaluation. Give us a call and we can help you understand the numbers.

Question link

Can I use SafetySiren in a basement with no Wi-Fi?

Yes - this is actually one of SafetySiren's design advantages. It requires only a standard 120V wall outlet. No internet connection, no router, no smartphone needed.

Question link

Is SafetySiren accurate compared to other consumer monitors?

SafetySiren uses continuous electronic sensing and has been around as a product category for many years. Like any consumer monitor, accuracy depends on proper placement and allowing adequate time for reliable readings. It's a reasonable consumer indicator, not a professional measurement device, but it serves well for ongoing home monitoring.

Question link

How long does it take for SafetySiren to give a reliable reading?

Like most consumer monitors, SafetySiren should be allowed to run for at least 24-48 hours before the reading stabilizes. The manufacturer's guidance is to allow a longer settling period (sometimes several days) before trusting the displayed reading as representative. Radon levels also naturally fluctuate, so a 7-day-plus average is more informative than a reading from the first day.

Question link

Is SafetySiren recommended for post-mitigation monitoring?

It can be used for post-mitigation monitoring, though it doesn't provide the historical graphs and trend data that app-based monitors offer. If you want to simply glance at a display and see whether your post-mitigation level looks good, SafetySiren is fine. If you want to see the trend over time and compare seasonal variation, an app-connected monitor gives you more useful data.

Question link

SafetySiren vs Airthings - which should I buy?

SafetySiren is better for: no smartphone users, simple installations, audible alarm priority. Airthings is better for: historical data, app-based monitoring, remote access, trend graphs, multi-sensor options. Both measure radon continuously. The right choice depends on how you want to interact with the data.

Question link

My SafetySiren is several years old. Is it still accurate?

Consumer monitors can drift over time, and SafetySiren is no exception. If your device is 5+ years old and you're making a decision based on a reading, consider confirming with a professional test or comparing against a newer device. If the reading seems implausibly low or hasn't changed in months, the sensor may have degraded.

Question link

What is the RadonEye RD200?

The RadonEye RD200 is a consumer radon monitor made by FTLab (South Korea) that uses a pulsed ionization chamber sensor. It has a built-in display and connects to a companion phone app via Bluetooth. It's known for faster reading updates than many competing consumer monitors, making it popular with homeowners who want more responsive data. It's a reasonable consumer device for ongoing monitoring.

Question link

How does RadonEye differ from the Airthings Wave?

The key difference is sensor technology. RadonEye uses a pulsed ionization chamber; Airthings Wave uses alpha spectrometry. The ionization chamber approach can update readings more frequently. Airthings Wave is Bluetooth-only with no display; RadonEye has a built-in display and Bluetooth app. Both are reasonable consumer monitors. RadonEye tends to be preferred by users who want fast feedback; Airthings tends to be preferred for its ecosystem, long-term history, and app quality.

Question link

Is RadonEye used by professional radon testers?

Some professionals keep a RadonEye for quick field assessments, but it's not a professional-grade continuous radon monitor (CRM) in the AARST/NRPP sense. Professional radon tests for real estate use devices that meet specific calibration, chain-of-custody, and documentation requirements that consumer monitors including RadonEye don't fulfill. A RadonEye reading at inspection is informative but not a substitute for a formal licensed measurement.

Question link

My inspector brought a RadonEye and said the house is fine at 3.9 pCi/L. Should I trust that result?

Be cautious. For a formal real estate test in Illinois, the test must be conducted by a licensed radon measurement professional using calibrated equipment under closed-building protocol. If your inspector used a RadonEye without being licensed for radon measurement, the test may not satisfy Illinois requirements. Ask for the inspector's Illinois radon measurement license number. 3.9 pCi/L is close enough to the 4.0 action level that a proper licensed test is worth doing to confirm.

Question link

How do I pair a RadonEye with my phone?

Download the RadonEye app for iOS or Android. Open the app, select "Add device," and follow the Bluetooth pairing instructions. The device must be powered on and within Bluetooth range (typically 30 feet). Check the current app instructions from FTLab for the most up-to-date pairing steps, as these can vary between app versions and device models.

Question link

Does RadonEye have historical data?

Yes - the RadonEye app stores historical readings and shows trend graphs. The amount of history stored and how far back you can view depends on the app version and whether data is stored locally on the device vs synced to a cloud service. Check the current RadonEye app documentation for your model.

Question link

The RadonEye reads in 10 minutes - what does that mean?

RadonEye's pulsed ionization chamber technology allows it to show a preliminary reading much faster than monitors that need to accumulate data over many hours. This doesn't mean the reading after 10 minutes is as accurate as one after 7 days - it means you get early feedback faster. Use the displayed reading as an early indicator, but rely on the multi-day or multi-week average for making decisions.

Question link

Can I export data from my RadonEye?

Some RadonEye models and app versions support data export. Check the current RadonEye app for an export or download option. If you need data for a specific purpose (professional comparison, personal records), verify that your app version supports this feature.

Question link

My RadonEye alarm went off. What do I do?

Check the displayed reading to understand the level. If it's above 4.0 pCi/L, the EPA recommends action. If it's a spike that came and went (open a window, watch what happens), note whether it's a consistent elevated reading or a transient event. If your average over several days is at or above 4.0, give us a call so we can talk through what mitigation would involve for your home.

Question link

My RadonEye fell off the shelf. Is it still accurate?

A single drop may or may not affect the sensor. After a fall, run it for 24-48 hours and compare readings to what you were seeing before. If the reading has shifted dramatically or is now giving unusual values (very low or very high without explanation), the sensor may have been damaged. Contact FTLab support or compare against a second source to assess accuracy.

Question link

Can I plug the RadonEye into the wall instead of using batteries?

Some RadonEye models support USB power input. Check the documentation for your specific model - not all support continuous AC power without a specific accessory. Using a USB power bank to avoid frequent battery changes is a common workaround for permanent basement installations.

Question link

Is RadonEye good for post-mitigation monitoring?

Yes - RadonEye's built-in display makes it easy to glance at current levels in the basement. The app provides trend history. It's a solid choice for ongoing post-mitigation monitoring. Keep in mind that the official post-mitigation test in Illinois must be done by a licensed professional - the RadonEye is your day-to-day check, not the required documentation.

Question link

My neighbor says RadonEye is more professional than Airthings because inspectors use it. Is that accurate?

RadonEye is a consumer monitor, not a professional CRM. Some inspectors carry them as quick-check tools, but this doesn't make them equivalent to professional measurement devices. Both Airthings and RadonEye are consumer monitors with similar limitations for formal testing purposes. "My inspector uses it" doesn't make a consumer device meet professional measurement standards.

Question link

My RadonEye and a professional charcoal test gave different numbers. Which is right?

Differences between consumer monitors and professional tests are expected. A charcoal test under closed-building conditions with specific protocol gives a result that represents defined testing conditions. Your RadonEye reads under real-world conditions - which include open windows, people coming and going, and all the normal variation of a lived-in home. Both readings are information. For a decision (whether to mitigate), the professional test under defined conditions is more defensible.

Question link

Can I use RadonEye to verify mitigation before the professional test?

Yes - as an informal check. If your RadonEye shows 0.8 pCi/L three days after installation, that's a strong early indicator the system is working. But the official Illinois post-mitigation test requires a licensed professional regardless of what your consumer monitor shows.

Question link

Why does radon tend to be higher in winter?

In winter, homes are closed up tight - windows shut, less ventilation, negative pressure from heating systems. The temperature difference between indoors and outdoors creates a "stack effect" that draws soil gases (including radon) up through foundation openings. This is normal and expected. If you're using a consumer monitor, you'll likely notice higher readings in January than July. This is one reason professional testers often recommend testing under closed-house conditions - to capture a more representative (and typically higher) result.

Question link

My radon is much higher in winter than summer. Should I use the winter or summer reading for my decision?

The higher reading - winter - is more representative of your actual exposure, because you spend more time in a closed house in winter. If your winter reading is above 4.0 pCi/L and your summer reading is 2.0 pCi/L, your integrated annual exposure is closer to the higher end. Professional tests are typically run under closed-house conditions to better represent this.

Question link

Why does radon spike when it rains?

Barometric pressure drops during storms, and soil gases (including radon) can expand more easily into lower-pressure indoor air. Heavy rain also saturates the soil around the foundation, which can push soil gases - including radon - through cracks and openings more actively. Storm-related spikes are normal and usually temporary. If your long-term average is elevated, that matters more than a single storm spike.

Question link

Does snow cover affect radon levels?

It can. Snow on the ground acts as a seal over the soil, reducing radon escape to the outdoors. This can push more soil gas toward the foundation and into the house. Snow cover combined with a closed house and cold weather is often when homeowners see their highest readings. This is expected behavior.

Question link

Does running the furnace fan continuously reduce radon?

Running the furnace fan circulates air through the house but doesn't specifically dilute or exhaust radon. Some homeowners see modest reductions when the fan mixes basement and upper-floor air, but this isn't a radon solution - it's air circulation. A mitigation system specifically addresses the source of radon entry and is the appropriate solution for consistently elevated levels.

Question link

Can an ERV or HRV help with radon?

An Energy Recovery Ventilator (ERV) or Heat Recovery Ventilator (HRV) brings in fresh outside air while recovering heat energy. This can help dilute indoor radon by introducing outdoor air. However, ERVs and HRVs are primarily designed for general indoor air quality, not radon mitigation. If radon is consistently above 4.0 pCi/L, an ERV alone is not the standard solution - sub-slab depressurization (radon mitigation) is. An ERV may help somewhat, but it's not a substitute.

Question link

Does opening windows every day in summer keep radon low?

It can lower readings significantly during the open-window period. Many homeowners see much lower summer readings when windows are regularly open. This doesn't mean the radon problem is solved - when windows close in winter, levels will return. If your summer reading is low but your winter reading is elevated, the underlying radon source is still there. Testing under closed-house conditions gives a more accurate picture of your actual risk.

Question link

Does my basement dehumidifier affect radon levels?

A dehumidifier circulates basement air and removes moisture, but it doesn't introduce outside air or exhaust basement air. Some homeowners notice small reading changes near a running dehumidifier due to air movement. The dehumidifier alone doesn't resolve radon issues and doesn't substitute for mitigation.

Question link

Does a fireplace affect radon levels?

A fireplace can create negative pressure in the house as it draws air for combustion. This negative pressure can pull soil gases - including radon - in through foundation cracks and openings. Heavy fireplace use, especially in a tight house, can correlate with elevated radon readings. If you use a fireplace frequently and have elevated radon, the fireplace combustion dynamic may be a contributing factor.

Question link

My radon monitor reading rises overnight. Is the house getting more radon while we sleep?

Yes - this is a common and expected pattern. At night, the house is closed up, people are less active, there's less air exchange, and barometric pressure often drops slightly in the early morning hours. These factors combine to produce higher radon readings in the early morning than in the afternoon. The overnight period is when radon tends to accumulate in a closed home. This is one reason good radon monitoring matters - you're sleeping in the highest-radon period of the day.

Question link

I opened all the basement windows for a week and my radon reading dropped to 0.6 pCi/L. Does that mean the problem is solved?

No - it means radon dilutes significantly with ventilation, which is expected. The source is still there. When you close the windows in fall and winter, levels will return. Ventilation is a temporary management approach, not a permanent fix. Mitigation addresses the source by preventing radon from entering the home in the first place.

Question link

My radon reading went up after I had my HVAC ducts cleaned. Why?

Duct cleaning can temporarily increase air movement and pressure in the home. If there are cracks or openings in the foundation and the pressure dynamics changed (more positive or negative pressure in certain areas), it could temporarily affect radon entry. If the elevated reading persists for more than a week after the work, it may not be related to the cleaning at all. Watch the trend over the next 7-14 days.

Question link

My radon spiked during a cold snap. Is that real or is my monitor having an issue?

Cold snaps can cause real radon spikes. Cold weather means closed windows, more stack effect (cold air sinking draws soil gases up), and potentially drier soil conditions. A cold-snap spike is real data. If your monitor has been accurate before and the spike correlates with a weather change, trust the reading. Watch to see whether it returns to your prior baseline once conditions moderate.

Question link

Does barometric pressure affect my consumer monitor reading or just the actual radon level?

It affects the actual radon level in your home - the monitor is accurately reporting what's there. Lower barometric pressure (ahead of storms) allows soil gas to migrate more easily into lower-pressure indoor air. The monitor isn't "confused" by pressure changes; it's picking up genuine changes in radon concentration. This is exactly the kind of information a continuous monitor provides.

Question link

My radon is lowest in August and highest in January. Is that a seasonal pattern I should show my mitigation contractor?

Yes - that seasonal pattern is useful context. It confirms that your home has a baseline radon source that gets worse under closed-house winter conditions. This is typical for many Midwest homes. If your January average is at or above 4.0 pCi/L, that's the relevant decision point. A mitigation system will reduce levels year-round, and you'll still see some seasonal variation afterward but at much lower levels overall.

Question link

Can my cat knock over my radon monitor?

Yes - and if the monitor falls, check whether the reading changes unexpectedly in the following days. A single fall usually doesn't damage the sensor, but it's worth watching. If you have curious pets, consider placing the monitor on a shelf that's out of reach or securing it with a small velcro strip.

Question link

Does a radon monitor detect smoke, CO, or natural gas?

No. Consumer radon monitors measure only radon - they don't detect smoke, carbon monoxide, or natural gas. You need separate dedicated detectors for those. Smoke detectors, CO alarms, and natural gas detectors are separate devices. Don't use a radon monitor as a substitute for any of those.

Question link

Why does my radon reading go up when I shower?

Your shower doesn't directly produce radon, but hot showers increase humidity and can slightly pressurize the bathroom, pushing air around the house in ways that temporarily affect readings. More commonly, if your water supply is from a well with elevated radon in the water, showering can release dissolved radon into the bathroom air - but this is a different issue from soil-source radon. For most homes on municipal water, the shower effect on a radon monitor is minor.

Question link

My toddler unplugged the radon monitor. Does the data reset?

Depends on the model. Most consumer monitors retain internally stored data when power is interrupted - the device resumes recording when plugged back in. But if your Airthings Wave had batteries removed, some models start fresh from the next power-on. Check the behavior of your specific model. If data was synced to the app or cloud before the interruption, that history is preserved.

Question link

My monitor is covered in dust from a renovation. Does that affect the reading?

Significant dust buildup on or inside the sensing chamber can affect accuracy. After a dusty renovation, gently clean the exterior of the device (follow the manufacturer's guidance on cleaning). Let it run for a few days after the renovation is complete and conditions return to normal before relying on the reading. If the sensor appears clogged, contact the manufacturer for guidance.

Question link

My radon monitor got wet in a basement flood. Is it still accurate?

A monitor that has been submerged or heavily exposed to water should be assessed carefully. Dry it out completely before powering it on again if it uses batteries. Even if it powers on, internal moisture may affect sensor accuracy. Compare readings against a known source or professional test before trusting it again. For a significant flood event, contacting the manufacturer is the safest approach.

Question link

Can radon monitors freeze in an unheated basement?

Most consumer monitors have operating temperature ranges specified in their documentation. Extended exposure to freezing temperatures can damage electronic components. If your basement regularly drops below 32°F in winter, a monitor stored there may not give reliable readings and could be damaged. Check the manufacturer's operating temperature range for your specific device.

Question link

My radon monitor fell off the shelf. Is it still accurate?

Give it 24-48 hours and see if the reading seems consistent with what you were seeing before the drop. A fall may or may not damage the sensor - it depends on the impact. If readings appear dramatically different after a fall, the sensor may have been affected. Compare against a fresh professional test or contact the manufacturer.

Question link

My toddler moved my radon monitor to a different room. Does that reading count?

The location matters. If the monitor was moved to a bathroom, kitchen, or room near an outside door, the reading from there won't represent your lowest-level occupied space. Move it back to its original location and give it at least a week to re-establish a reliable reading for that spot.

Question link

I went on vacation for 2 weeks. Is the data from an unoccupied house meaningful?

It's informative - it tells you what radon does in your house when it's unoccupied and naturally sealed. This reading may actually be higher than typical occupied-house readings because the house was closed continuously. It's real data, not meaningless, though it may not represent your typical occupied conditions exactly.

Question link

Does my radon monitor measure anything other than radon?

No - consumer radon monitors measure only radon. Some multi-sensor devices like the Airthings Wave Plus add CO2, VOC, temperature, and humidity - but the radon reading is a separate sensor channel. A radon monitor will not detect natural gas leaks, smoke, or carbon monoxide.

Question link

Can I put my radon monitor next to my TV or electronics?

Electronics themselves don't affect radon sensors directly. Keep the monitor in the breathing zone and away from vents, windows, and heat sources. Placing it directly on top of a hot appliance or in a spot where electronics create significant airflow could affect readings - but in most living spaces, a nearby TV or receiver won't cause a meaningful problem.

Question link

My radon monitor is in a closet. Is that a valid location?

Closets have reduced air circulation, which can make readings artificially high - air stagnates rather than representing what you're breathing in the room. Move the monitor to an open area of the room at breathing-zone height where air circulates freely.

Question link

I put my radon monitor in the garage. Is that meaningful?

If it's an attached garage with an interior door to the house and you spend time in it, a garage reading is interesting - but the priority is to measure the living space. If the garage is detached and unoccupied, it's not a useful measurement for your personal exposure. Move the monitor to the lowest occupied living space inside the home.

Question link

My radon monitor is right next to a sump pit. Should I move it?

Yes - moving it away from the sump pit is a good idea. Sump pits are a common radon entry point, and a monitor directly next to an unsealed pit will show locally elevated readings that may not represent the general basement air. Move the monitor to the middle of the basement at breathing-zone height, away from the sump pit, exterior walls, and HVAC vents.

Question link

Does carpet hold radon?

No. Radon is a gas and moves through air - it doesn't accumulate in carpets or furniture. The radon level in the air of your basement is what matters, and the carpet under your monitor doesn't change that reading. Carpet is not a radon-mitigation tool and is not a radon risk factor on its own.

Question link

Can I test radon during a renovation?

Renovation work that opens walls, cuts floors, or disturbs the slab can temporarily create elevated radon readings because you're essentially creating new pathways for soil gas. If you're in the middle of a renovation, the reading may not be representative of normal conditions. Test after the renovation is complete and the home has been sealed back up for at least a week.

Question link

I painted my basement and my radon reading dropped. Does paint lower radon?

Temporarily closing off cracks or sealing concrete can reduce radon entry points slightly, but paint alone is not a radon mitigation strategy. The drop may be real but short-lived as the paint settles and any microscopic openings return. Don't rely on painting as a radon solution.

Question link

My basement flooded. Should I move the radon monitor before cleanup?

Yes - move it to higher ground before the flood restoration begins. Restoration work (fans, dehumidifiers, water extraction) will create unusual air movement that won't represent normal radon conditions. Give it at least a week after the work is complete and the space has returned to normal before trusting readings again.

Question link

I have a wood stove in the basement and my radon goes up when I use it. Is that connected?

It can be. A wood stove draws combustion air from the surrounding space and creates negative pressure in the basement. That negative pressure can pull soil gases - including radon - in through foundation cracks and openings. If you notice your radon consistently rises on wood stove days, the negative pressure from combustion is a likely factor.

Question link

Can I use my radon monitor on the second floor to test radon up there?

You can, but second-floor radon levels are typically lower than basement levels. If you're concerned about a specific room (a first-floor room that's at or near grade, or a room above a crawlspace), testing there makes sense. But for most homes, the basement is where you want to monitor - it's where radon concentrations are highest and where the exposure risk is greatest.

Question link

I have an old radon monitor from the 1990s. Is it still accurate?

Monitors from that era are almost certainly too old to be reliable. Sensor technology has advanced significantly, and older devices have had decades of operation that could degrade the sensor. If you're making any decision based on radon levels, use a current device or get a professional test. Don't rely on a 30-year-old consumer monitor for anything meaningful.

Question link

I left my Airthings Wave in a hot car for a day. Could that damage it?

Extreme heat can damage electronic components and may affect sensor accuracy. After heat exposure, allow the device to cool to room temperature before powering it on. Run it for a few days and compare readings to what you were seeing before. If readings look unusual, contact Airthings support.

Question link

My monitor reading barely changes day to day. Is that good or bad?

Very stable readings over many days usually mean either consistently stable radon conditions (possible in some homes) or that the device may have an issue. If the number is exactly the same to the decimal for more than 3-4 days, that's unusual - most consumer monitors show some variation. Try syncing/refreshing data and check that the device is powered and connected properly.

Question link

Can I put my radon monitor inside a large piece of furniture, like inside a bookshelf cubby?

Enclosed furniture spaces restrict air circulation and can artificially trap radon, giving elevated readings that don't represent the open room. Place the monitor on a surface where air can circulate freely around it - not inside a cabinet or cubby.

Question link

Related Help

System diagnosticsRadon testing guidanceContact Bill

Questions are fine too. Call or text Bill, or send your address and contact info, and he will take it from there.

Reviewed by Bill Dahlstrom, Illinois radon mitigation license RNM2018212.