What Is Radon?

Radon is a naturally occurring radioactive gas produced by the breakdown of uranium in soil and rock. It's present in the ground almost everywhere, in small amounts, but it becomes a health concern when it seeps into enclosed spaces like homes and buildings and accumulates to higher concentrations than it would ever reach outdoors.

Radon is colorless, odorless, and tasteless. There is no way to detect it with your senses. Testing with a proper device is the only reliable way to know your indoor radon level.

Radon gas moves up from the soil and enters buildings through any point of contact with the ground: cracks in foundation slabs and walls, gaps around pipes and wiring penetrations, sump pits, and even through some porous concrete itself. Once inside, radon can become trapped and build up to levels much higher than outdoors, especially in basements and lowest lived-in levels.

Prairie homes, including many in Brandon and the surrounding Westman region, face a particular combination of factors: soil conditions in this part of Manitoba that tend toward higher radon potential, and a long heating season that keeps homes sealed tightly for much of the year to conserve heat. That combination of tighter building envelopes and regional soil profile is part of why Manitoba shows up in Health Canada's national data as a higher-than-average radon region.

Health Canada's guideline for indoor radon, sometimes called the action level, is 200 becquerels per cubic metre (Bq/m³) averaged over a full year. Testing can be done with a short-term device (2 to 7 days) for a quick initial read, or a long-term/continuous monitor (90 days or more) for a result that better reflects year-round exposure across different seasons and heating conditions.

If your result comes back at or above 200 Bq/m³, Health Canada recommends mitigation. The higher above that guideline your result is, the sooner mitigation is recommended.