How to Reduce Radon Levels

A Guide for Homeowners

Radon is a radioactive gas produced by the natural breakdown of uranium in soil, rock, and groundwater. It’s invisible, odorless, and tasteless – yet it poses one of the most significant hidden threats to indoor air quality.

As radon gas escapes from the earth, it can infiltrate homes through cracks in foundations, construction joints, or gaps around service pipes. Over time, this gas can accumulate to dangerous levels indoors, creating serious health concerns for occupants.

The primary concern surrounding radon exposure is its link to lung cancer. According to the EPA, radon is the second leading cause of lung cancer in the United States, contributing to thousands of deaths each year. What makes radon particularly dangerous is that its presence produces no immediate symptoms – people can live in a home with high radon concentration for years without realizing their risk.

Geography, building structure, and environmental conditions all play a part in indoor radon levels. Homes in high-risk zones, especially those with basements or built on permeable soils, tend to be more vulnerable. Seasonal changes also affect indoor radon levels. During winter, homes are sealed tightly to conserve heat, which can lead to higher radon level buildup.

Unfortunately, there's no way to detect this silent gas without testing. No amount of visual inspection can uncover it, which is why radon testing is the only reliable method to identify a problem.

If you're wondering why you should test for radon, it’s simple: it's the first step toward protecting your health and making informed decisions about mitigation.

The Importance of Radon Testing

The only way to determine if your home has a high radon level is through accurate radon testing. Because radon can fluctuate based on pressure, ventilation, and weather, even neighboring homes can have drastically different readings. You can’t assume you're safe just because your neighbor is.

There are many reasons to test for radon – from protecting your family's health to complying with real estate requirements – and early detection allows you to take meaningful steps before radon exposure becomes a long-term concern.

There are two main categories of radon testing:

Short-term radon testing provides a snapshot of radon levels over a period ranging from 2 to to 4 days. This type is helpful for quick assessments, such as during real estate transactions.
Long-term radon testing offers a more accurate understanding of year-round exposure, accounting for seasonal and daily fluctuations.

Understanding how to test for radon and using the best radon test kit for your home can make all the difference. The placement of the kit is key – experts recommend researching where to place a radon test kit based on your home’s layout. Other tips include placing it in the lowest livable level of the home, away from drafts, high humidity, or direct sunlight.

Some homes – particularly those with basements or crawlspaces – are more prone to radon buildup. In these cases, repeated testing or a radon testing kit that allows long-term measurement is even more important. Certain structural features and HVAC systems can also influence radon concentration, making targeted placement and follow-up testing essential.

When interpreting results, the measurement is expressed in picocuries per liter (pCi/L). The EPA recommends mitigation if radon levels are at or above 4.0 pCi/L. However, even levels between 2.0 and 3.9 pCi/L may still pose radon exposure risks, especially with long-term exposure. In Canada, the measurement is expressed in bequerels per meter cubed (Bq/m3). Health Canada recommends mitigation if levels at at or above 200 Bq/m3 .

For ongoing peace of mind, homeowners in high-risk areas or homes with fluctuating readings may want to explore continuous monitoring solutions. These professional devices track changes in radon concentration in real time and are a great complement to traditional tests. Continuous monitors can also provide insight into daily patterns that might help with identifying radon mitigation strategies if needed.

At Radonova, we offer high-quality radon test kits for homeowners. Our products are trusted for their reliability, ease of use, and laboratory precision.

How to Reduce Radon Levels After Testing

If your radon test reveals elevated levels, don’t panic – but do act. Reducing high radon levels is entirely possible with a combination of short-term and long-term strategies.

Immediate Steps After Testing

Begin by ventilating the space. Open windows and use fans to improve airflow in lower levels of your home. This increases circulation and can help reduce indoor radon temporarily. Avoid using exhaust fans in kitchens or bathrooms during this process, as they can pull more radon into the house from the ground.

Sealing and Airflow Improvements

Cracks in floors, foundations, and walls are common entry points for radon gas. Sealing these with polyurethane caulk or other appropriate materials can help block pathways, though it should be part of a broader strategy – not the sole approach.

Improving subfloor ventilation in crawl spaces with vapor barriers and fans can also decrease radon concentration. Additional techniques like installing vent pipes or using a heat recovery ventilator (HRV) can support radon mitigation by enhancing overall airflow and reducing buildup.

If you're looking for a detailed overview of DIY options, this DIY radon mitigation guide is a place to start. It provides practical tips for homeowners who want to take proactive steps before calling in professionals.

Why Retesting Matters

After any mitigation effort, retesting is crucial. This confirms whether your radon reduction efforts were successful or if further steps are needed. Consider a follow-up test 2–4 weeks after implementing changes to get an accurate picture of new radon levels.

Even if your initial mitigation strategy seemed effective, subtle changes in your home’s airflow such as a home renovation, , weather conditions, or foundation repair can alter indoor radon concentrations over time. That’s why retesting should be viewed not as a one-time event, but as part of a long-term radon safety plan. If you're using a radon mitigation system, follow-up testing also validates the installation’s effectiveness and helps identify any maintenance needs.

In homes where radon has fluctuated seasonally or reached levels close to the EPA action threshold, regular retesting – every one to two years – is strongly recommended. This proactive approach helps homeowners stay ahead of radon exposure risks and make timely adjustments if radon concentration begins to rise again.

By incorporating ongoing testing into your home health routine, you gain better control over air quality and long-term well-being. Whether you’re testing with a continuous monitor or a reliable kit, each retest plays a vital part in keeping your home safe.

Understanding When Professional Mitigation is Needed

If your radon test reveals elevated levels, don’t panic – but do act. Reducing high radon levels is entirely possible with a combination of short-term and long-term strategies.

For results that are both effective and lasting, it’s important to work with a certified contractor – ideally someone listed by the National Radon Proficiency Program (NRPP) or C-NRPP in Canada. A professional can help you understand the specific dynamics of your home and choose the right system for it. After installation, follow-up testing is again necessary to confirm the system is performing correctly and has successfully reduced the radon concentration in your home.

Why Regular Radon Testing is Essential

Even if your last test showed low radon levels, conditions could change. Foundation shifts, renovations, weather patterns, and HVAC upgrades can alter airflow and radon entry points. This is why experts recommend testing every two years – or more frequently in high-risk regions or after structural changes.

Environmental Influence

Rain, snow, barometric pressure, and temperature changes all influence radon concentration. Winter months often yield higher readings due to sealed windows and increased indoor heating, which creates a vacuum that draws more radon into the home.

Ongoing Monitoring

For families living in known radon-prone areas, long-term monitoring or digital radon detectors can offer continuous insight. They help identify trends and alert you to spikes in radon gas levels before they become hazardous. Routine testing is an easy, affordable way to stay on top of potential problems and maintain safe indoor air.

Taking Control of Your Indoor Air

Radon is a dangerous, invisible threat that can exist in any home – regardless of age, design, or location. Because it’s impossible to detect through sight or smell, testing is the first – and most important – step in protecting your family’s health.

Let’s recap:

Radon gas exposure is a major health risk and a leading cause of lung cancer.
The only way to detect a problem is through reliable radon testing.
There are effective steps homeowners can take to reduce radon levels after testing, including sealing entry points, improving airflow, and installing a radon mitigation system if needed.
Professional help may be necessary when DIY efforts fall short.
Retesting is critical, as radon levels can shift with time and environmental changes.

You don’t have to live with uncertainty about the air you breathe. Start today by ordering a radon test kit from Radonova. Our products are trusted globally for their precision and ease of use – helping you make informed decisions quickly and confidently. Explore our full range of testing solutions, gain access to expert radon information, and take the next step toward a safer home.

Don’t wait for symptoms. Don’t guess. Test today with Radonova.