Radon in the basement test it when people use the room
The gas forms in the soil, and the house draws it in because the house is warmer than the ground. The first volume of air affected is the lower one: basement, crawl space, slab on grade. Going up a floor often dilutes the level. It does not make it zero.
Finished basement or not
If there is a bedroom, an apartment, an office or a room where people spend hours, the detector goes in that room. If it is only storage, measure the lowest lived-in floor. Height and distance from supply vents.
Sump and cracks
An open sump, a drain and the holes around plumbing are possible entries. Sealing them can help a little. The fix that holds, when the level is above 200 Bq/m³, is still suction under the slab. How the system works.
The 4-day test gives a first reading. The 91-day test covers the three-month minimum Health Canada asks for. Both are $59 before tax: shipping, return and the laboratory are included, taxes extra. The PDF report is sent within 2 business days after the laboratory receives the detector.
Above 200 Bq/m³, mitigation is confirmed with a quote. Gaz Radon is C-NRPP certified for measurement and mitigation.
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