[jchw]

I have a brick house and a basement, and I have no radon mitigation system, and I live in an area where radon is generally a concern (southeast Michigan.)

Over the last couple years I've had some AirThings sensors collecting data. Last month:

- The one-day average radon concentration detected by the basement sensor crossed over 3 pCi/L once... for a very brief period. Around 80% of the time, the one-day average radon concentration detected by the basement sensor was below 2 pCi/L.

- The one-day average radon concentration detected by the main floor sensor never reached 3 pCi/L and was rarely above 2 pCi/L.

In fact, since January, the main floor sensor has still never reached 3 pCi/L even once, or really gotten all that close. The basement sensor, on the other hand, has reached 4 pCi/L three times this year, with a peak at 5.1 pCi/L for a brief period in May.

I hardly ever check this data, but it is nice to have it. I guess it would probably be wise to double check some other way to make sure that the AirThings sensors are outputting good information, but I have little reason to doubt it.

As long as I'm interpreting the data right, though, it suggests that despite having some of the worst case scenarios for my house, actually it's fine. So I guess it really does depend mostly on the land you're built on. (That, and, you should probably just check instead of guessing.)

[ragingroosevelt]

My understanding is that a radon reading of 2 is the upper bound for reasonable regular exposure. If you're seeing above that, I'd be inclined to look into mitigation.

[jchw]

I'm not an expert but I've read enough to know this is not a serious concern. If you were to see a reading above 2.6 pCi/L from a one-time test, that would be more concerning, but what I'm actually seeing is occasional jumps above 2.6 pCi/L that last less than a day from continuous monitoring. We're talking events that last on the order of hours for a few days a year... I can open a damn window. The vendor for my sensor recommends taking action if the level is above 4 pCi/L for an entire month, but for me it's barely above 2.6 pCi/L at all. In some months neither sensor ever gets above that.

I think on the contrary if you have a tendency to worry too much things like continuous monitoring systems might not be the best thing for your mental health. I actually was pretty worried since I'm a mild hypochondriac and a friend told me that they got obsessed with CO2 monitoring after getting one. Thankfully for me it has mostly been an occasional curiosity since there's nothing too concerning.