Review on Portable Airthings Corentium Home Radon Detector 223: Lightweight, Easy-to-Use, USA Version, pCi/L by James Kelley

This is one of the most important $200 purchases I've made. Having this in my basement was very open and showed me the following: - The radon abatement fan installed in my home, running in the green (according to its vacuum gauge), is essentially not doing anything to reduce radon levels. On or off, same averages. *See update below, I no longer believe this is absolutely correct. Just DO NOT rely on a radon ventilator as your only protection. Radon levels can vary LARGE when fans are used. My basement averaged around 1 pCi/L for a few months and then jumped to over 5 when we turned on the heat. I believe the heater lowered the relative pressure in the basement (by venting air through the chimney), causing much more gas to be drawn in through cracks in the concrete slab and foundations. I'm in the process of fixing this and this tool gives me the information I need to know if my changes (crack repair, venting, etc.) are making a difference. We see that our radon levels have dropped to their lowest levels due to our improvements thanks to the help of this tool that tells us what works and what doesn't. You simply CANNOT rely on a "pro" to come to your home and check your radon level, even if it has been tested over a long period of time. The average radon level in your home over a week or month doesn't make sense when it can change so drastically from month to month. If you live in a place where radon is known to be a problem (I'm in CO), you need constant monitoring. Air under my basement tiles. With the unit on, multiple cracked windows, and the central basement air intake closed to increase relative pressure, I was able to obtain average radon readings from 5 pCi/L (dangerous) to 0.50 pCi/L (safe) regardless of the air temperature. the stove runs sporadically.