Radon comes up more and more often when I inspect homes in Canmore and Banff. Buyers have heard of it, but most aren't sure what a test involves or what to do with the number. Here is how I explain it to my clients.
What radon is
Radon is a radioactive gas released when uranium in soil and rock breaks down. It has no colour, smell or taste. Outdoors it disperses, but it can seep into a house through foundation cracks, floor drains, sump pits and gaps around pipes, and build up in the lower levels.
Health Canada calls radon the number one cause of lung cancer for non-smokers in Canada. That is the reason to test: you can't see or smell it, and the only way to know the level in a particular house is to measure it.
Why one house can differ from the next
Radon levels depend on the ground under the house, the foundation, how the house is sealed and how air moves through it. Two homes on the same street can give very different results. A neighbour's test, or a test from the house's previous owner years ago, doesn't tell you much about the home you are buying today.
What a radon screening is
A screening is a short-term measurement taken while the home is being inspected or shortly after. It gives an early reading of the radon level in the house. I offer radon screening in the Canmore and Banff area, either together with a home inspection or on its own.
A short-term result is useful as a first look. It is not the final word, and Health Canada is clear about that:
- Health Canada recommends testing for at least 91 days, ideally three to twelve months, with part of the test in the heating season, when houses are closed up.
- Its guideline is 200 becquerels per cubic metre (Bq/m³) as an average over the year in the normal living area.
- Short-term measurements are not appropriate for deciding on mitigation. That decision should come from a long-term test.
So if a screening shows an elevated level, the next step is a long-term test, not an immediate repair.
If the long-term result is high
If a long-term test is above 200 Bq/m³, Health Canada recommends reducing the level within a year, and sooner the higher the result. Radon reduction is a job for a contractor certified under the Canadian National Radon Proficiency Program (C-NRPP). Common fixes include sealing entry points and installing a system that draws radon from under the floor and vents it outside.
Fitting it into a purchase
Most purchase conditions in Alberta run for days, not months, so a long-term test usually can't finish before you remove conditions. That is where a screening helps. It gives you an early indication during your condition period, and you can plan a long-term test once you move in.
Booking
You can add radon screening when you book your inspection, or call me on 780-224-1151 if you have questions. For more background, Health Canada's guide to radon measurement and Take Action on Radon both have plain-language information for Alberta homeowners.
Kyle Dowdeswell, Certified Master Inspector®, Rocky Mountain Home Inspections, Canmore