How is radon measured?
Short-term and long-term tests, what the numbers mean, and why a single reading isn't the whole story.
Radon is measured in becquerels per cubic metre (Bq/m³) in Canada. Testing is done with either a short-term device (a few days to a week) or a long-term device (three months or more), usually placed in the lowest lived-in level of the home.
Short-term tests give a quick snapshot, but radon levels fluctuate with season, weather, and ventilation. A long-term test gives a much better picture of the actual exposure in a home.
Health Canada's guideline is 200 Bq/m³. Above that, mitigation is recommended. The number is a guideline for action, not an alarm — and the right response is a proper measurement followed by a clear conversation about options.
This article is general education, not a diagnosis of your home. For a proper assessment of your specific situation, talk to us.