While surveying client properties in Europe, we had a month-long radon monitoring session (continuous measurement) at our client’s house. Our radon meters have convincingly reported radon build-up in the basement area of the house in the colossal range above 1,200 Bq/m3 (12 times above the considered safe zone of 100 Bq/m3).
We decided to try ventilation alone, but the values remained in the danger zone of over 150 Bq/m3. Thence we took the decision to build an improvised #radon mitigation system. The result was convincing just 24 hours later. From values of above 150 Bq/m3, we have reduced radon levels to 60 Bq/m3 after the radon mitigation system was put in place.