When Veronica was diagnosed with lung cancer...I read that radon gas is by far the single greatest cause of lung cancer in non-smokers. I bought a radon gas detector from Best Buy and have been monitoring it ever since.
During the summer levels were low : 40 - 50 Bq/M3 (Metre cubed)
Now with the house closed up for winter weather, the range has extended to higher than 250Bq/M3 on some days and is typically in the 150-200 range.
100 is considered an alert level, over 200 for any extended period is considered dangerous.
I am now looking into radon gas mitigation.
Graeme Shelford