Air exchangers and radon dilution is not suction under the slab
An air exchanger, or HRV, sends stale air out and brings outdoor air in. In a tight house, that helps with humidity and everyday pollutants. Radon arrives continuously from the soil. Diluting the air does not stop the source.
What you can expect
A well-set unit can lower the concentration a little, sometimes unevenly from room to room. It can also, if it unbalances the pressures, change the way the house draws on the soil. Ventilation alone is not a promise of a result under 200 Bq/m³.
The order of the steps
Measure first, with the house as it is, the HRV running as usual. If the report is above 200 Bq/m³, the reliable path is a system that pulls under the slab and exhausts the gas outside, above the roof. Where the pipe runs.
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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