How Does Radon Testing Work?
Radon is an invisible, odorless radioactive gas that can accumulate inside homes. Because it cannot be detected by sight, smell, or taste, testing is the only way to determine your home’s radon levels.
Radon testing measures the concentration of radon in indoor air, typically reported in picocuries per liter (pCi/L). Common testing methods include electronic continuous radon monitors (CRMs) and passive test kits that are sent to a laboratory for analysis.
At Total Radon Solutions, we offer FREE radon testing throughout Utah. We help homeowners understand the testing process, explain their results, and make informed decisions without pressure or obligation.
For more information about radon testing, visit the U.S. Environmental Protection Agency’s radon information page.
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Continuous Radon Monitors vs. Charcoal Test Kits
Continuous Radon Monitors (CRMs)
Continuous radon monitors are electronic devices that measure radon concentrations at regular intervals throughout the testing period. They provide detailed information about how radon levels change over time and allow us to review the results when testing is complete. At Total Radon Solutions, we typically use professional CRMs for homes within approximately 75 miles of Ephraim, Utah.
Charcoal Radon Test Kits
Charcoal test kits are passive devices that absorb radon during the testing period. Once testing is complete, the kit is sealed and sent to a laboratory for analysis. These kits provide an average radon concentration over the exposure period rather than the detailed hourly readings available from a CRM. For homeowners farther from our Ephraim location, we can mail a free charcoal test kit with instructions for completing the test.
Both methods can provide reliable results when properly conducted. The most important factors are correct placement, following testing instructions, and maintaining the required testing conditions.
How Long Does a Radon Test Take?
Most radon testing performed by Total Radon Solutions involves short-term tests lasting approximately 48 hours. A significant portion of our testing is associated with real estate transactions, where buyers and sellers need timely results to meet their due diligence deadlines.
For nearby homes, we typically use professional continuous radon monitors (CRMs), which measure radon concentrations throughout the testing period. These instruments allow us to review the results promptly after testing is complete. For homeowners farther from our Ephraim location, we provide charcoal test kits that are mailed to the home. These kits generally require two to several days of exposure, depending on the manufacturer’s instructions, followed by laboratory analysis.
Long-term radon tests lasting more than 90 days can provide a better estimate of a home’s average radon exposure over changing conditions and seasons. However, properly conducted short-term tests are often the most practical choice when results are needed quickly, particularly during real estate transactions.
Follow-Up Testing After Radon Mitigation
At Total Radon Solutions, follow-up testing is part of our mitigation process. After installing a radon mitigation system, we provide testing to verify how effectively the system is reducing radon levels. We don’t consider an installation complete simply because the equipment is running. We want to know that the system is achieving the results we’re working toward.
We also encourage homeowners to obtain independent third-party post-mitigation testing, as recommended by industry standards. Independent verification provides additional confidence in the results and complements the follow-up testing we provide.
When Additional Testing Is Needed
If follow-up testing shows that radon levels have not reached our desired target, we investigate further rather than automatically recommending another mitigation system. We may conduct additional monitoring over longer periods and move testing equipment to different areas of the home to better understand where elevated radon concentrations persist.
This information helps us determine the most appropriate next step, which may involve increasing fan capacity, adjusting the existing system, or making other improvements. Our goal is to achieve effective radon reduction using the simplest practical solution, guided by actual testing results rather than unnecessary equipment.
How Should You Prepare Your Home for a Radon Test?
Proper preparation is essential for obtaining reliable radon test results, especially during the 48-hour tests commonly performed for real estate transactions. At Total Radon Solutions, we explain the testing requirements so homeowners, buyers, sellers, and occupants understand what to expect.
For a typical 48-hour radon test, closed-house conditions must be maintained for at least 12 hours before testing begins and throughout the entire testing period. Windows should remain closed, and exterior doors should be kept shut except for normal entry and exit. You can continue coming and going from the home, but doors should not be left standing open.
Heating and cooling systems that recirculate indoor air can generally operate normally. Equipment that brings substantial amounts of outside air into the home, such as evaporative coolers (swamp coolers), whole-house fans, and window fans, should not be operated during the test. Existing radon mitigation systems should remain operating normally.
Testing equipment must remain in its designated location and should not be moved, covered, unplugged, or disturbed. Radon testing is generally performed in the lowest level of the home suitable for occupancy, away from drafts, excessive humidity, and other conditions that could affect the results.
How Our Monitors Help Protect Test Accuracy
Our professional continuous radon monitors include features that help identify possible interference during testing. Both types of monitors we use can detect movement and record changes in temperature and humidity. We can review this information alongside the radon readings to identify unusual conditions that may require further investigation.
This added monitoring is particularly valuable during real estate transactions, where buyers and sellers depend on reliable test results. Unusual readings or environmental changes do not automatically mean someone has intentionally interfered with a test, but they can help us recognize conditions that may affect its validity.
Severe storms and unusually high winds can also influence short-term radon measurements, so testing may need to be postponed or repeated under certain conditions. Following the proper testing procedures helps everyone involved have greater confidence in the results.
What Do Your Radon Test Results Mean?
Radon test results are reported in picocuries per liter (pCi/L), a measurement of radon concentration in indoor air. The Environmental Protection Agency (EPA) recommends taking action to reduce radon when test results are 4.0 pCi/L or higher. Because no level of radon exposure is considered completely risk-free, the EPA also recommends considering mitigation when levels are between 2.0 and 4.0 pCi/L.
One important thing to understand is that radon levels are not constant. They can rise and fall considerably throughout the day and night. Our professional continuous radon monitors often reveal peaks and valleys, sometimes including substantial short-term spikes. These fluctuations are one reason radon test results must be interpreted carefully.
Why Do Radon Levels Rise and Fall?
Weather conditions, temperature differences, barometric pressure, wind, soil moisture, and ventilation can all influence radon concentrations. When warm indoor air rises and escapes from a home, lower pressure near the foundation may draw additional soil gases, including radon, into the building. This is commonly called the stack effect.
Changes in rainfall, soil conditions, and atmospheric pressure can also affect radon movement. As a result, a home may record noticeably different readings from one day to another, even when occupants have not changed anything inside the home.
Why Are Radon Levels Often Higher in Winter?
During Utah’s colder months, homes are typically kept closed, reducing the amount of fresh outdoor air entering the building. Greater differences between indoor and outdoor temperatures can also increase pressure differences that draw radon into the home. These conditions often contribute to higher winter radon concentrations, although individual homes may follow different seasonal patterns.
During spring and summer, open windows, doors, and increased ventilation may temporarily reduce indoor radon concentrations. However, a lower reading during warmer weather does not necessarily mean the home will have low radon levels throughout the year.
Can a Home Test Low for Radon and Still Have a Problem?
Yes. Radon levels can be temporarily reduced by ventilation, seasonal conditions, and changes in air pressure without addressing the underlying source of radon entering the home.
For example, opening windows and doors can introduce fresh air that dilutes indoor radon. Evaporative coolers, commonly called swamp coolers, may have a similar effect. They bring outside air into the home and, under certain operating conditions, create positive indoor pressure that can reduce the amount of radon entering from beneath the foundation.
When colder weather arrives, windows are closed, swamp coolers are turned off, and changing pressure conditions may increase radon entry. A home that recorded relatively low radon concentrations during summer could experience substantially higher concentrations in winter.
This is why a single low reading does not necessarily tell the whole story. Temporary reductions caused by ventilation are not the same as controlling radon entry with a properly designed mitigation system. Proper testing conditions and the potential for seasonal fluctuations should always be considered when interpreting results.
Why the Average Radon Level Matters
During a properly conducted 48-hour test, our continuous radon monitors collect readings throughout the testing period. These readings reveal fluctuations, but the overall test average is generally the most important number when comparing results with the EPA’s recommended action level.
A temporary spike does not automatically mean the overall test result is elevated, just as several low readings do not guarantee that the home has no radon problem. The average concentration, testing conditions, and applicable testing guidelines all matter when interpreting the findings.
Because a short-term test represents a limited period, additional testing may sometimes help provide a clearer picture of a home’s radon levels. Long-term testing can better estimate average exposure over changing seasons. During real estate transactions, however, properly conducted 48-hour tests are commonly used because decisions must be made within limited due diligence periods.
At Total Radon Solutions, we help homeowners understand their results, explain how changing conditions may affect radon levels, and discuss additional testing or mitigation options when appropriate. Our goal is to provide reliable information and practical solutions without unnecessary sales pressure.
Is Radon Testing Required When Buying or Selling a Home in Utah?
Utah does not generally require radon testing when an existing home is bought or sold. However, sellers should disclose known radon conditions through the applicable property disclosure process, and buyers can request testing as part of their home inspection and due diligence.
Because radon is invisible and odorless, testing is the only way to determine a home’s radon concentration. A properly conducted 48-hour test can provide valuable information within the limited time available during many real estate transactions.
Can Your Mortgage Lender Require Radon Testing?
Yes. Certain federally supported housing and financing programs have specific radon testing and mitigation requirements. Individual lenders may also require testing or establish additional conditions before approving a loan. These requirements depend on the financing program, property type, and lender; they do not apply automatically to every government-backed home loan.
At Total Radon Solutions, we are seeing more requests for testing associated with mortgage and financing requirements. Buyers, sellers, and homeowners refinancing a property should ask their lender early whether radon testing is required and whether specific documentation or testing procedures are needed.
Does a Radon Mitigation System Make a Home Harder to Sell?
Some homeowners hesitate to install a radon mitigation system because they worry it may create a stigma or discourage future buyers. However, an existing mitigation system with documented follow-up testing can provide reassurance that elevated radon levels have already been addressed.
A properly functioning radon mitigation system can sometimes reduce concentrations to levels lower than those found in homes that originally tested below the EPA’s 4.0 pCi/L action level. For example, a successfully mitigated home measuring 1.0 pCi/L has a lower radon concentration than an unmitigated home measuring 3.0 pCi/L. Results vary by home, and continued testing is important to confirm system performance.
Rather than automatically viewing a mitigation system as a negative feature, buyers can recognize that it represents a proactive effort to control radon exposure. Installation records, follow-up test results, and information about system operation can help buyers better understand the home’s condition.
At Total Radon Solutions, we provide follow-up testing after mitigation to verify our results and determine whether additional adjustments are needed. We also encourage independent third-party testing for additional confidence. Our goal is to help homeowners achieve effective radon reduction and have documented results they can share with prospective buyers.
Ready to Test Your Home for Radon?
Whether you’re buying or selling a home, checking your family’s radon exposure, or simply looking for peace of mind, Total Radon Solutions is here to help. We offer FREE professional radon testing using continuous radon monitors for homes within approximately 75 miles of Ephraim, Utah, and free mailed test kits for homeowners farther away. We’ll help you understand your results and discuss any recommended next steps, without pressure or obligation.