What to see how much Radon Gas there is in you house?
I did, so I got the "Corentium Home by AirThings, Radon Gas Detector, USA version in pCi/L".
The operation is very simple. It takes for it few days to display the levels. Then you have to place mount it to the wall an from time to time take a look at the levels.
This meter is so easy to operate and it make it so easy to monitor your radon gas levels.
Please see more info at amazon USA
Please see more info for UK