To be fair, California has cool nights and in LA you're likely opening all your windows in the summer/spring/fall evenings to cool off your house. Rainy weeks

To be fair, California has cool nights and in LA you're likely opening all your windows in the summer/spring/fall evenings to cool off your house. Rainy weeks are the worst for radon in our house because we keep everything closed 24/7. It reaches around 6. But our yearly average is more like 1.9. It's probably still high enough that I'll do something about it eventually, but it's not high on my priority list.