I am a retired chemist so I’m concerned about radon emissions. I had absolutely no knowledge of this product or company until I found out that have a lot of radon in my new home. So, I purchased a model 223 a couple weeks ago and am using it to help me understand the situation while I wait for remediation. It’s doing a wonderful job of informing me of ‘hot spots’ and the average level throughout the house while I hold my breath. Now to its accuracy. The Corentium 223 specification is perhaps the most honest approach to accuracy I have ever seen in a consumer product. It’s based on: ‘sigma = less than [a percentage and the length of test]. It is statistical probability specification of accuracy and it is rich in accuracy information. However, you need to do the math, understand what ‘sigma’ means in variance statistics, understand probability distribution curves, and then the use the spec to calculate the worst case accuracy of the device associated with your own radon situation). So, please do that before you criticize the device. If you studied the specification and did the math, as I have, you would see that it is quite accurate for an inexpensive radon continuous monitoring device.... and way more than suitable for home use. Let me repeat that again. If you use the device as instructed by the manufacturer and are willing to trust the specification as determined by some very smart people who spent a lot of time, money and brainpower to prepare it, then you will be measuring Radon and its variability in your home in a way that is vastly superior to doing periodic mail away tests. The radon in your home varies from day to day, month to month, hour to hour. The anecdotal ‘evidence of accuracy’ presented in virtually all of these reviews is absolutely without merit. Why, because determining the accuracy of the device against a standard source is extremely complicated. As a chemist I know that for a fact. We, as customers, do not have the time, money, equipment, or knowledge to do it - period. If you are somehow guessing that you need better accuracy in a shorter period of testing then please consider buying the Corentium pro for $1200 or perhaps some other professional device. You may not get better accuracy but you will likely get equivalent accuracy in a shorter period of time.... that’s how the statistics work. Please read the last two sentences again. Consider this too. The manufacturer, Air Things, is based in Europe and it appears to be a spin off of CERN in Geneva, Switzerland. Look up CERN in Wiki. You will be impressed. They are the world’s leading experts on making and measuring radiation. I am impressed because their ‘no calibration necessary’ technology for this device (and their more expensive professional models) seems to be the result of a micro miniaturized, more precise spectroscopic technology for measuring radioactive decay of radon daughters alpha particle emissions. Finally, I’ve read literally hundreds of these Amazon reviews where accuracy is mentioned... and actually is somehow mysteriously determined in the basement of their home. However, I’ve not seen one review that references the manufacturer’s specification. Everyone here that’s comparing ‘this to that’ or ‘that to this’ and making claims about ‘accuracy’ doesn’t have a clue what they are talking about. However, a number of thoughtful reviewers seem to have run side by side tests with other devices or mail away canisters. Assuming those tests were done properly, then they can be considered slightly helpful but otherwise of no use in determining the device’s accuracy. I’m going by the specification. I’m confident in my device and am very relieved that I own one. —- UPDATE: April 28, 2021 I bought a second unit a couple months after purchasing the first, so both are now over two years old. I am very happy with both units. No problems - I lent one out to my daughter for a few months. Now I keep one in the basement and the other on the first floor. I recently replaced the batteries in the first unit (a two year battery life - just like the manufacturer said) and have had no problems at all with either unit. Regarding Accuracy - I am reiterating that the Airthings accuracy specifications (which result from the highly advanced ‘spectroscopic’ technology behind it) are extraordinary for a low priced unit. Don’t believe the misinformation from reviewers here who claim to have determined the ‘accuracy’ of their Airthings unit as bad or good by running some kind of ‘test’. You/ Me / Other Reviewers / cannot in any way determine the accuracy of any type of radon device or test kit on the market - not for any device - not for any manufacturer). Period. The only choice you have for determining the accuracy of any device you buy is to trust the manufacturer, the manufacturer’s statistical process control, and that the manufacturer truly, deeply understands the extremely complex issues in radon measurement. The Airthings company was founded by CERN scientists. CERN is where many of the smartest on this planet create and measure radiation with the Large Hadron Collider (LHC). So... I trust the Airthings accuracy specification. So - If you really want to know the accuracy of any type of any radon monitoring detector you purchase (regardless of the manufacturer), here is what I would recommend so as to get decent accuracy results. - identify an analytical laboratory highly specialized and experienced in the many complexities of radon measurement - ensure that it is a laboratory using standards and equipment based on measuring radon in the atomic form(s) in which it is most carcinogenic, - send them your device and have it tested under tightly controlled laboratory conditions for a period of time (that is dependent on the rate at which that particular device model approaches the true radon value). For me, buying two of the Airthings devices was an easy decision once I researched and understood the issues in Radon measurement, and the various devices available. As I said previously, I have no affiliation of any kind with this company, but I do get frustrated when reviewers who have no clue what they are talking about provide horrible misinformation for the rest of us.
