Radon testing is an important step in understanding the indoor air quality of a home. Radon is a naturally occurring radioactive gas produced by the breakdown of uranium in soil and rock. Because it is invisible, odourless, and tasteless, homeowners cannot identify its presence without testing.

Radon can enter buildings through cracks in foundations, gaps around pipes, construction joints, and other openings in contact with the ground. Once inside, it can accumulate, particularly in lower levels of buildings. Health Canada recommends corrective action when the average annual radon concentration in a normal occupancy area exceeds 200 Bq/m³.

Understanding how radon testing works can help homeowners make informed decisions about their property and determine whether additional steps, such as radon mitigation, may be necessary.

Why Is Radon Testing Important?

Many homeowners assume that a newer or well-maintained property will not have high radon levels. However, radon concentrations can vary considerably between homes, including properties located close to one another. Building age alone cannot determine whether a home has elevated radon.

The only reliable way to know the radon concentration inside a property is to conduct a radon test. Health Canada notes that every home has some level of radon, but the amount can vary significantly.

Testing is particularly important for homes with basements or other occupied areas in contact with the ground. It can also be useful after major renovations, energy-efficiency upgrades, structural changes, or installation of a radon mitigation system.

How Does Radon Testing Work?

Radon testing involves placing a measurement device in an appropriate area of the home for a specified period. The device measures the concentration of radon in the indoor air.

For residential properties, Health Canada recommends long-term testing lasting at least 91 days when estimating the average annual radon level. A longer measurement period helps account for natural fluctuations in radon concentrations.

The testing device should generally be placed on the lowest level of the home that has a normal occupancy area, such as a bedroom, living room, office, or playroom. It should be positioned in an area where it will not be moved and where normal airflow is maintained.

Short Term and Long Term Radon Testing

There are different approaches to radon measurement, but homeowners should understand the difference between short-term readings and long-term averages.

Short-term measurements can provide useful information about current conditions. However, radon levels naturally rise and fall because of factors such as weather, ventilation, building conditions, and seasonal changes.

Long-term radon testing provides a more representative measurement of a home's average exposure. Health Canada states that decisions about corrective action should be based on measurements lasting at least 91 days.

For example, a detector might record occasional readings above 200 Bq/m³ while the long-term average remains below the Canadian guideline. This is why relying on a single short-term reading can sometimes provide an incomplete picture.

Where Should You Place a Radon Detector?

Proper placement is essential for obtaining useful results. Health Canada recommends placing the device in the lowest lived-in level of the home, in a room where people normally spend time.

The detector should be kept away from windows, doors, vents, and locations where unusual airflow could affect the measurement. It should also remain undisturbed throughout the testing period.

Following the manufacturer's instructions is equally important when using a radon testing device. Incorrect placement or improper handling can affect the reliability of the measurement.

What Does a Radon Test Result Mean?

Radon concentrations in Canada are measured in becquerels per cubic metre, abbreviated as Bq/m³. Health Canada's current guideline is 200 Bq/m³ for the average annual radon concentration in a normally occupied area.

If a long-term test produces an average above 200 Bq/m³, Health Canada recommends taking corrective action to reduce exposure. The higher the concentration, the sooner corrective measures should be taken.

It is also important to understand that there is no completely risk-free level of radon exposure. A result below the Canadian guideline does not mean that radon is completely absent; rather, it indicates that the measured average is below the level at which Health Canada recommends corrective action.

When Should You Test Your Home for Radon?

Radon testing can be performed at any time, but long-term testing that includes the heating season can provide useful information about annual exposure. Health Canada recommends retesting in certain circumstances, including after renovations that affect the home's structure or ventilation.

Retesting may also be appropriate after energy-efficiency improvements, significant excavation near the property, structural damage affecting areas in contact with the ground, or installation of a radon mitigation system.

For homes with an active soil depressurization system, Health Canada recommends testing every five years to confirm that the system continues to function as intended.

What Happens If Radon Levels Are High?

A high radon test result does not mean that the situation cannot be addressed. Radon mitigation systems are designed to reduce the amount of radon entering and accumulating inside a building.

One commonly used approach is active sub-slab depressurization. This system draws soil gas from beneath the building and vents it safely outside. Other solutions may be appropriate depending on the property's construction, foundation, crawlspace, and soil conditions.

After mitigation, follow-up radon testing is important to verify that the system has effectively reduced indoor radon levels. Health Canada recommends post-mitigation testing and ongoing monitoring in appropriate circumstances.

Why Choose Professional Radon Testing?

Professional radon testing can be useful for homeowners who want assistance with test placement, measurement, interpretation, and next steps. A qualified professional can also help identify testing conditions that may affect results.

For properties with unusual layouts, crawlspaces, multiple occupied levels, or previous mitigation work, professional guidance may make the testing process easier to manage.

The goal is not simply to obtain a number. Effective radon testing should provide information that helps homeowners understand their property's radon exposure and determine whether further action is appropriate.

Learn More About Ottawa Radon Pros

For homeowners looking for radon testing and mitigation services in Ottawa, Ottawa Radon Pros provides radon testing, radon removal, and radon mitigation services. The company states that it serves Ottawa, Kanata, Cornwall, Vanier, and surrounding areas, and offers professional testing and post-mitigation testing. Its website also describes services including active sub-slab depressurization, active soil depressurization, and radon mitigation system repair or upgrades.

To learn more about available services, testing options, and radon mitigation solutions, visit https://ottawaradon.pro/ .

Conclusion

Radon testing is a practical way to determine whether a home contains elevated concentrations of this naturally occurring radioactive gas. Because radon cannot be detected through sight, smell, or taste, testing is the only way to understand indoor levels.

A long-term test of at least 91 days provides a more representative estimate of average annual radon exposure. If the average concentration exceeds Canada's 200 Bq/m³ guideline, corrective action should be considered.

By testing your home, understanding the results, and taking appropriate action when necessary, you can make informed decisions about indoor air quality and long-term radon exposure.