Radon Action Month in Edmonton: Your 91-Day Radon Test Should Start Now (2026)

Meta description: November is Radon Action Month. Start your Edmonton radon test now so it covers 91 heating-season days, with placement, devices and next steps explained.

Direct answer: November is Radon Action Month in Canada. For Edmonton homes, start your long-term radon test now: Health Canada requires at least 91 days of testing during the heating season, and a test started in mid-November fits that window comfortably.

Why does Radon Action Month matter in Edmonton?

Could your home have elevated radon even if your neighbour’s test was low? Yes. November is Radon Action Month in Canada, and the Take Action on Radon Knowvember campaign runs from September 25 to November 30. It’s a timely reminder to check your own home rather than rely on someone else’s result.

Radon is the number one cause of lung cancer for non-smokers in Canada and is classified as a Group 1 carcinogen by the International Agency for Research on Cancer (IARC). There is no level considered risk free. Because radon levels can vary widely between homes, even on the same street, testing is the only way to know the level in your home.

I’m Banti K Shaw. After more than 10 years in inspection and construction, I’ve learned that a home’s appearance cannot tell you its radon level. Measurement gives you the information to decide what to do next.

Read Take Action on Radon’s Radon Action Month information and our earlier radon testing Edmonton guide for more background.

What is the 91-day heating season rule?

Will a test started now give you enough heating-season days? If you begin in the first half of November and leave the device in place, it can comfortably cover the minimum.

Health Canada’s Guide for Radon Measurements in Homes requires at least 91 days of a test to fall during the heating season. It recommends a total test period of 3 to 12 months. A test with fewer than 91 heating-season days risks underestimating the annual average and may mean you need to retest. Keep your household routine normal during a long-term test.

A simple timeline: Start around November 12. The 91-day mark lands around mid-February, still within Edmonton’s heating season. For a more representative result, leave the test in place longer if your device instructions allow it, within Health Canada’s recommended 3-to-12-month period.

Where should the radon device go in your home?

Which room reflects the air you and your family actually breathe? Choose a normal-occupancy area on the lowest lived-in level. Health Canada defines normal occupancy as a space where someone spends more than 4 hours per day.

Suitable locations may include a finished basement family room, guest room, office, workshop or basement apartment. Crawl spaces, unfinished basements, cold rooms, furnace rooms and laundry rooms are not normal-occupancy areas for this purpose.

Set the device in the breathing zone, at least 30 cm (1 ft) above the floor and at least 30 cm from walls or ceilings. Keep it:

• At least 1 m from vents, windows, doors and HVAC airflow.
• Away from direct sunlight, heat sources, electronics and Wi-Fi routers.
• At least 10 cm from other objects to allow airflow.
• Out of reach of children and pets.

Never place it in the kitchen, laundry room or bathroom, or near sump holes, crawl spaces or exposed foundation cracks. Bedrooms on the main floor or basement are priorities because people generally spend more time there than in any other room. If you have children, consider a basement playroom where they spend substantial time.

“The most common mistakes I see are a device on the basement floor, a kit left beside a sump pit, and a two-week reading treated as the final answer. Placement and patience decide whether a radon test tells you anything useful.”

Banti K Shaw

Which radon device should you choose?

Do you want a lab-tested average or readings you can watch over time? Both passive and active devices can be options, but choose a device on C-NRPP’s approved lists, as Health Canada recommends.

• Passive devices: Alpha track detectors and electret ion chambers are sent to a lab for analysis. They report the average over the test period. Check an alpha track detector’s expiry date before starting.
• Active devices: Electronic radon monitors (ERMs) display near real-time readings. Use the long-term average when interpreting the result, not brief fluctuations.

The C-NRPP consumer monitor report regularly performance-tests consumer-grade electronic monitors and publishes an approved versus not-approved comparison. Many inexpensive online monitors have failed performance testing or have been recalled by Health Canada for inaccurate readings, so check the current list before buying.

Health Canada advises considering replacement of an ERM five years after purchase unless it is recalibrated. Many consumer models cannot be recalibrated. You can use Take Action on Radon’s test kit finder to explore long-term kit options.

How do the numbers work out if you start now?

What should you make of a result close to 200 Bq/m³? Treat it as an estimate, not a perfectly exact number. Health Canada’s guide notes that repeated tests can vary by up to plus or minus 25% under CSA and ANSI standards. A result slightly below 200 Bq/m³ may be above the guideline in reality, and a result slightly above may be below it.

Health Canada’s guideline is an annual average of 200 Bq/m³ in a normal-occupancy area. The guide recommends:

• Below 200 Bq/m³: Retest within the next 5 years.
• At or above 200 Bq/m³: Take action to reduce levels within one year, and sooner the higher the level.

Base decisions on the long-term average, not short-term spikes. Short-term readings can be misleading, showing levels much lower or much higher than the actual average.

When should you retest after this one?

Could a change to your home make an old result less useful? Yes. Health Canada recommends retesting during the next heating season after certain changes, including:

• Renovations affecting structure or ventilation, such as a basement renovation, new furnace or added bathroom.
• Energy retrofits, including new windows, insulation or air sealing.
• Excavation or earthwork next to the home.
• New structural damage to the slab or basement walls.
• A change that makes the basement the lowest lived-in level.
• Installation of a radon mitigation system.

Newly built homes should be tested during the first heating season and again 2 years after construction. If your home has an active soil depressurization system, retest every 5 years. A mitigation system does not guarantee the level is below the guideline, so testing still matters.

For related indoor-environment considerations, see InspecUs’ air quality testing Edmonton information.

What is my recommended next step?

What can you do today to get a useful answer? Choose a long-term device from an approved list, put it in the right room, and start your test. Then leave it undisturbed and follow the device instructions.

As an inspector, I encourage you to use a result as information for a decision, not a reason to panic. If you’re buying a home, you can also consider a pre-purchase home inspection in Edmonton as part of your property due diligence. If you have questions about your next step, contact InspecUs. I’m here to help you understand the process and make an informed choice.

Frequently asked questions

Still unsure about your test plan? Here are four quick answers to common questions.

Can I stop testing as soon as the monitor shows a high reading?

No. Use the long-term average to compare with the guideline. Short-term readings can be misleading, so keep testing for the recommended period and follow the device instructions.

Is a two-week test enough?

A test needs at least 91 days during the heating season to meet Health Canada’s minimum. A shorter test may underestimate the annual average and may require a retest.

Should I change how I use my home during testing?

No. Health Canada advises residents not to alter their lifestyle during a long-term test. Keep your normal household routine.

Does a home with a mitigation system still need testing?

Yes. Homes with mitigation systems can still exceed the guideline. Health Canada recommends retesting active soil depressurization systems every 5 years and testing after a mitigation system is installed.