Radon in a semi-detached house the party wall does not share the result
The neighbour’s 80 Bq/m³ does not cover your bedroom. The other half may have the sump, a cut slab, or a fireplace every night. Yours may be the opposite. Each unit is tested in its own occupied room.
One fan can sometimes depressurize a continuous slab. Sometimes it cannot. You only know after a test on each side and a look at the foundation. One fan, two units. Buying.
The 4-day test is a first reading. The 91-day test covers the three-month minimum Health Canada asks for. Both are $59 before tax. Shipping, the return and the lab are included. Tax is extra. The PDF report goes out within 2 business days after the lab receives the detector.
Above 200 Bq/m³, mitigation starts with a quote. Gaz Radon is C-NRPP certified and ships kits across Canada. See the Canada test page.
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