Bests & Worsts Reviews from Amazon

This is one of the most important $200 purchases I've made. Having this in my basement was extremely eye opening, showing me that: -The radon mitigation fan that was installed in my house, which is working in the green (according to its vacuum indicator), does essentially nothing to reduce radon levels. On or off, same averages. *See update below, I don't believe this to be completely accurate anymore. Just don't RELY on your radon fan as your only means of protection. -The radon levels can swing WILDLY when air-moving appliances are in use. My basement averaged around 1 pCi/L for months, then shot up to over 5 when we began running the heater. I believe the heater was lowering the relative pressure in the basement (exhausting air via flue), causing far more gas to be sucked in through the cracks in the concrete slab and foundation walls. I'm currently in the process of remedying that, and this tool gives me the info I need to know if my changes (patching cracks, ventilation, etc) are making a difference. We're seeing our radon drop to the lowest levels yet due to our improvements, thanks to the help of this tool letting us know what is working and what is not. You simply CANNOT rely on some "professional" coming into your house and testing your radon level, even if tested over a long period of time. The average radon level in your house over a week or month is meaningless when it can change so drastically month to month. If you live in a place where radon is known to be problematic (I'm in CO), then you need continual monitoring. *Update: After a lot more testing, I've come to appreciate my 80 watt radon mitigation fan that pulls air from beneath my basement slabs. With it on, a few windows cracked, and the central air intake in the basement sealed to increase relative pressure, I've managed to get radon averages from 5 pCi/L (dangerous) to 0.50 pCi/L (safe) regardless of the heater occasionally running.