How to test your home for radon: Using an electronic radon monitor or a long-term detector

Step 1: Choose the right device

Electronic radon monitor (ERM): Choose one that has passed the C-NRPP performance testing.

or

Long-term detector: Purchase a long-term test kit.

Step 2: Find the best spot

Do place the device:

• on the lowest lived-in level (family room, bedroom, playroom, finished basement, etc.)
• at breathing height (0.5 to 2m from the floor)
• on a flat surface (table, shelf, desk) or hanging from the ceiling or wall

Don't place the device:

• in kitchens, bathrooms, laundry rooms, closets, or unfinished basements
• near windows, doors, vents, or exterior walls
• near heat sources (fireplaces, direct sunlight)
• near electronics or appliances (TV, fridge, microwave, etc.)

Step 3: Start your test

Electronic radon monitor:

• Follow the manufacturer's instructions to set up the monitor.
• Place it in the chosen spot and let it run continuously.
• Leave it in place for 3 months (longer is okay, up to 12 months).
• Set a reminder to check the long-term average reading after 3 months.

Long-term detector:

• Take the detector out of the package.
• Record the start date, time, and location as per the test kit instructions.
• Store the test kit materials (instructions, return envelope) in a safe place.
• Leave it in place for at least 3 months (up to 12 months is fine).
• Set a reminder to return the detector after 3 months.

Step 4: End your test

Electronic radon monitor:

• After 3 months, check the long-term average reading on your monitor.
• Follow the manufacturer's instructions to access your results.
• Keep using the ERM for continuous monitoring or share it with family and friends.

Long-term detector:

• After 3 months, record the end date and time.
• Follow the test kit instructions to return the detector to the lab.
• Mail it in as directed. If you lost the instructions, contact the test kit provider.

Step 5: Get your results and take action

• Results can be read directly from your ERM or smartphone application or will arrive in 3 to 6 weeks for long-term detectors.
• If your radon level is 200 Bq/m³ or higher, take action to reduce it within 1 year.
• Hire a C-NRPP certified radon mitigation professional to lower the radon level in your home.

For more information, visit Radon - Canada.ca or call 1-833-723-6600.