Airthings Corentium Home Radon Detector 223 Portable

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.

It took a little over 12 hrs before it started reading so tahe your time. It says it can take 24 hrs. The scary part is that mine was very high 8.24 It should be no more than 4 Yes I have 2 crawl spaces. I got a air purifier and have it on 1rst floor and am happy with it it has a charcoal filter. I ordered another today for basement. I did some study on Radon gas. It comes from the ground from decomposing metals and minerals that came down in the glaciers and deposited here in Iowa. I has the 2nd highest death and cancer rate in the US. There are 21,000 Radon cancer related deaths a yr in US. 400 alone in Ia. a yr. I have a inline charcoal water filter for whole house. I also got a water test kit from amazon and mine was perfect but I still got another charcoal filter for kitchen sink for pets plants and drinking. It is same system as the air filter. Called reverse something. I also looked up all it was testing. Over 5 caused cancer and my neighbors unfiltered tested just below stopping point of drinking. U can't boil chemicals out of water. Only bacteria. Charcoal is the only way for air and water. The water test is much more than this tester. It took out everything in my water. LOL in looking this stuff up many times the said the worst water U can drink is bottled water. LOL YA Really. Joke is they say it's spring water but U can't drink that anymore. The water comes out of a filtered tap just like mine. The bad part is the bottle, It puts 1,000's of tiny plastic partials in the water. we also put these bottles in our land fills that brake down and get in our water systems. Back to the air. If I can clean the Radon out of my home with the charcoal it will take everything else also. This meter is a must to know what U are dealing with, and if U are gaining. They have Co. that say they can rid your house and ground around U from Radon but U can't stop it in the ground. I looked at a diagram of there systems which all they are is a very expensive exzost system. I did same thing with my bathroom exost fan. Yes I cracked a window in front of house and back also. There system pulls air out of basement to outside. All but radon we are putting in the ground. There is so much more to this U could write a book on how we are killing ourselves. Since I got the water sink filter my cat has gained some weight. Yes I give her and my plants it. Will let U know more if I get the Radon under control. All U can do is get it out faster than it comes in. Remember mine was 8.24 and Max for same drinking is 4, They say best is 1.4 have a long way ta go and its winter here. Also all I spoke of I got here from amazon.

As of right now I am rating this little gadget a 5/5!! (Until I get my lab results back) I never write reviews but when looking for something to read the radon levels in my home and immediately turning to the reviews I decided I should pass along my opinion as well. Our house was built in 2021, we moved in that same year, we got the house tested before closing and we were told by a mitigation tech that it wasn’t any concern due to the level not being too high. Fast forward to 2025 I decided it would be a good idea to take a peak at the levels. It came back at 16.02 (long term) & 17.27(1 day) which is very high, we placed it in the lowest level in ours house. I let it sit for about a week so it could get a good reading. The levels stayed about the same so I decided it was best to have a mitigation system put in. After an entire day of have the mitigation system running the numbers went down to 14.16, there is no way that this gadget knew that the mitigation system was installed. After 10 days of having the installation It currently reads 9.02 (long-term) & 1.59 (1 day). I’m extremely happy with those numbers I’m looking forward to the lab results to compare the accuracy.

Purchased my 1st one in 2016 when my last home failed a home inspection, requiring a radon remediation system to be installed to sell the home. It now lives in my basement utility room and it's been flawless. Now that my office is in the basement, the wife wanted to monitor radon levels in that room as well. I was interested in comparing measurements between old and new units side-by-side to validate if the old unit is any good 9 years later. My first radon detector from another company is only good for a year before needing re-calibration, which requires shipping back to the manufacturer. These Corentium detectors auto-recalibrate with a reset button, which I do after replacing the batteries. So how did the old detector do when compared side-by-side with a new one? Great! There's only a 2% difference between units, which is less than the published accuracy threshold. So these are worth the added cost.

[Update 2: August 2016] In Feb 2016 I ran another side by side comparison of the Corentium 223 vs the SS (Safety Siren), and this time using two charcoal tests as "controls." All four were placed around the same spot (pictures do not show the charcoal tests but they were right next to the Corentium and SS). The Corentium and the SS were turned on at the same time and allowed to run until the SS started to show a result (due to the SS not showing an initial reading until a couple days after turning it on or resetting it, whereas the Corentium starts showing a reading almost immediately). Once the Corentium and SS were on for a few days I opened both charcoal tests and left them open for 4 days (the longest time allowed by the lab to get legitimate/accurate results). Then I sealed up the charcoal tests and mailed them in and checked the readings of the Corentium and the SS which had now been on for 7-days (the reason for 7 days is that the devices both provide readings at 7 days but other readings are at different time parameters and so not comparable). The results are shown in my pics (3rd-6th pics). Charcoal Test #1: <0.5 pCi/L Charcoal Test #2: <0.6 pCi/L Corentium 223: 0.97 pCi/L ("7 days" reading) Safety Siren: 1.2 pCi/L ("S"=7 days reading) Please note that I bought both the Corentium and the SS in March 2014 and so both were almost 2 years old at this point. I'm not sure the charcoal test results and those of the Corentium and the SS can be compared directly since their readings are over different times (approximate 4 days for the charcoal test vs 7 days for the two devices; I had to do this since the charcoal tests cannot be tested for more then 4 days and the two devices do not show readings at shorter times (e.g. 3 days, etc.). Interpreting the results is not exactly easy or maybe even valid, but it does at least seem to show that the devices are not wildly different than the charcoal readings and more importantly, they seem to read higher rather than lower than the charcoal readings (i.e. they do not give falsely low readings). It also shows that the charcoal tests are very close to each other and therefore probably a reliable test (i.e. repeated testing yields values close in value to each other) and are assumed to be the most accurate way to test radon levels. Another finding is that the SS, which needs re-calibration annually, had higher values compared with the Corentium (which is not supposed to need retitration over the life of the device which is stated as about 10 years). However, when I left the two devices on for a few more days (see the 6th pic) I found that the values became much closer to each other: 0.9 for the SS and 0.94 for the Corentium. Conclusions? I would say that based on my amateur and non-expert tests and interpretation of the results, that both devices are probably reliable and accurate enough to get a decent approximation of the radon levels in your home. The SS, though cheaper than the Corentium, is uglier and needs a wall power adapter whereas the Corentium is smaller, better looking, lasts a long time on batteries, and can be hung on the wall. It also reportedly does not need re-calibration for the 10 year lifespan and so I consider the Corentium to be a superior device and would recommend it over the Safety Siren. [Update 1: March 2015] Sorry to the folks who were waiting to see the results of my side by side comparisons between this device, the Safety Siren, and the charcoal mail in tests. I've attached a photo of both detectors (along with the charcoal test, only did one of those) side by side after both had been sitting there for over a week. As you can see, the Safety Siren is set to short term reading, which I believe is the past 7 days reading, and shows at 1.6 while the Corentium shows 1.64 and is for the past 7 days also. So, based on this test (and I've done this several other times with the same, comparable results) both detectors seem to give similar readings. Of course, the gold standard seems to still be the charcoal, mail in kits and so I've attached a photo of that reading too. Basically, the kit shown in the pick was set out for the required time (48 hours) and mailed in promptly. The reading I got back from the company was 1.7 pCi/L, so pretty close to both detectors. The Safety Siren only goes to one decimal place and so is a bit more limited than the Corentium which goes out to 2 decimal places, but in reality 2 decimal places is probably not very valuable or helpful. So, to summarize, my test did show that the device is pretty accurate compared to a charcoal test and also that the Safety Siren was comparable -- although that device does not run on batteries and apparently needs to be recalibrated on an annual basis or so. The Corentium supposedly does not ever need to be recalibrated which just seems really odd to me. I will repeat these tests periodically and update this review on an annual basis (or until a better detector comes out than either of these!) to see how well the Corentium stands up over the years with regards to calibration need. I have also upgraded my rating to 4-stars. --- [Original Review: April 2014] Just want to point out that this radon detector does not wait for a couple days to give an initial radon reading, like some detectors do (like the Safety Siren Pro Series3 Radon Gas Detector - HS71512 by Family Safety Products, Inc. does), so basically within a minute or so of turning this device on for the first time (or after resetting), you will start to get initial readings that are predictably around 0.00 pCi/L. Obviously, getting a reading after 10 seconds isn't helpful, and I don't understand why it would give a worthless reading instead of making you wait for the necessary time (typically 2 days with the Safety Siren Pro detector) before giving you a reading. Over the next days/weeks, the reading will often steadily increase for the same reason, making you really question how useful this device is unless you wait at least a week or so. Even then, you're not sure if the 7-day reading is a weighted average -- meaning that those early really low readings would bring the average rating lower than it actually is. When I placed the Safety Siren Pro and the Corentium side by side for about 2 days in my basement near my sump pit, the readings were dramatically different: the Safety Siren gave a 1.7 and the Corentium around 0.56. Over the next couple days (again, the initial readings were after 2 days already), the Corentium reading starting to creep upwards, going from mid-0.5s to around 1.0 and then above, while the Safety Siren Pro stayed fairly steady around 1.7 Another couple days may bring the Corentium to around the reading of the Safety Siren Pro, which would make me feel better that they're both reliable if given enough time. I have ordered some charcoal testing kits (which get sent and read by a lab) to use as a kind of reference testing (supposed to be the best way to test apparently) to see which, if either or both, is accurate in detecting radon levels. I will update this review when it does come back, but preliminary testing with the Corentium leaves me unimpressed, especially for the hefty price tag.

This radon monitor seems to be accurate. I have used it in several homes. Over 4 pci/liter is the recommended threshold to mitigate, in my area it’s not terribly unusual to see over 100. With a fan to pull a slight vacuum under the basement slab and vent to outside, the number drops to under 4. Not sure how harmful radon is, the famous Stanley Watras family discovered they lived in a home that was over 2500, was discovered when he set off radiation monitors on his way into work at a new nuclear plant which had no nuclear materials on site yet. Last I heard the family was doing ok decades later, so maybe radon isn’t quite as bad as they claim. Anyway I keep my little fan running just in case. And I like to have this around for when I want to test again.

The Airthings Corentium Home Radon Detector is exactly what I needed to monitor radon levels in my house. It’s portable, lightweight, and very easy to set up—just insert the AAA batteries and it’s ready to go. The readings are clear and consistent, giving me peace of mind about my home’s air quality. The USA version works perfectly, and I appreciate the accuracy and convenience of this device. Highly recommend for anyone wanting a reliable radon detector!

This device works great and is giving the correct reading which matched the charcoal canister reading. Ok people so until we get the Radon fan in do we keep the windows open or not? I read open windows is a bad thing because it sucks up more gas from the ground but it’s the only way to air out the house so it doesn't build up. I tested without windows and doors open and with open doors and windows, the readings go to normal when everything is open but what about all the build up from decay gas that settles... do we vacuum to get rid of the so called sticky Radon Daughters on the dust? according to the internet the break down of the gas called Radon Daughters is what causes the cancer in the lungs. How do we get rid of the Radon Daughters on the dust without making things worse in the air? Should we get air filters? So many questions and no answers how to clean up ... the Radon mitigation industry or investigations can't give us these answers on how to clean up radon daughters ourselves, we asked and they say “we don’t know we are just the installers” or "we don’t know we just test for it". I feel so helpless at this point. Some people say the whole Radon thing is a racket and BS and that the studies are inconclusive and some take it very seriously. Well it’s better to play it safe but how do we clean it up? My story...I’m freaked out!! We are selling our home and have been here 18 years. During inspection we were told our Radon in our basement is 37.4 pCi/L high. I am reading on the internet 50% of that is on the 1st floor and 50% of that is on the 2nd floor which is way too high on all floors. Sure enough this Corentium meter confirms it. According to all the blah, blah, blah on the internet this reading will most likely give people lung cancer if exposed for 15 years+ or a life time :( The internet states open windows only make things worse by sucking up more gas from the floor because open windows cause a suction. So here we are in a panic to get a fan installed in our Radon pipe which by the way we thought was working all these years and it turns out the builder never installed the fan which is necessary to get rid of Radon gas. All these years we were thinking the Radon pipe was working meanwhile the pipe was just sitting there inactive. I am soooo PO’ed!!! No one warned us about the high levels in our area also. Our town never sent out flyers to check levels or anything. Who do we blame? The builder? The Town? Ourselves? When we talk to others about this problem they say “what is Radon” If it’s so dangerous to ones health over time why doest everyone know about it? bad, bad, bad. Our Electrician can’t make it for a week to install the fan. Our house has been degrading my families health. we all have not been feeling well for years and have been sick (my husband had caner and is a survivor) including all my animals have one thing or another wrong with them including cancer with 2 of them. Now it all makes sense as to why my families and ALL my animals health has been going down hill. My cat lives in the basement and has cancer also. She only goes outside for a short time during the day then she comes back in to rest on her pillow. There are no studies on effects of Radon Gas with general day to day health. My nervous system is messed up in my house, I have vertigo, dizzy spells, tinnitus (ear ringing) and body numbness, my kids are always tired in the house and always complaining about not feeling well (winter is worse then summer) but when we leave the house for long periods of time our symptoms get better. The only help and answers we get is “ just install the fan and everything will be fixed” WHAT ABOUT THE LAST 18 YEARS!!! HOW DO YOU FIX THAT!!!! I am so UPSET!!! :( Update: The Corentium reader has been very helpful. We had the fan installed into the Radon pipe and the numbers are below 4 pCi/L now and settle in around 1 or 2. The fan was installed for $500. which I think was way to much for the time the man spent to install it. It only took him 10 min to install the fan. This was something we could of installed very easily since the pipe was already there. I suggest anyone that has a pipe already installed and is handy person... watch youtube videos on how to install the fan yourself and save some money. Also if there is no electric box then use a lightbulb screw in plug outlet because the Radon Mitigation installers will try to get another $250. out of you just to install an electric box which is unnecessary if you have a close by lightbulb socket. Hope this helps, meanwhile I am on a mission to get every piece of old dust out of our house because it is the dust that carries the break down of Radon and sticks in our lungs. The break down from Radon Gas is what causes Radon lung cancer. Also here’s a helpful hint... the reader will flash 4 bars when you first put those batteries in, the closer it gets to the finally reading it will flash 3 bars, 2 bars, 1 bar until ready to give you the results so you know it’s working if the flashing bars are going down. If you have high radon levels the Corentium reader will give a reading within only a few hours and if you have a low radon reading it will take 24 hours of flashing bars before it will give you a reading, that’s a very good sign your Radon level is low and safe. The longer it takes to give you a reading the better the reading will be and you can assume it will be a safe reading.

Easily the best purchase since we moved into our new house. We had 6.1 levels of radon on inspection, and installed a mitigation system. Upon moving in, we retested with that charcoal test--which involved leaving it for 36 hours, and then shipping it to Texas--and found levels were still at 3.9. We finally ordered this device, and were able to move it around the house over several weeks to identify the point of concern, a room on the opposite side of our mitigation system. We have the company coming back to install a second system, and feel confident that will do the trick! But we'd never have known the basement was such an issue on that side of the house without this device!! If you're unsure about the cost, compare it to a lifetime of comfort knowing the radon levels in your house are safe. Worth it!

Very accurate radon detection, for about the price of a single test kit. This will keep short and long-term track of your radon levels. I bought this to see if my basement required radon mitigation, and after getting the fan installed this now keep accurate track of the radon levels every day. It's easy to mount to the wall, so you can quickly glance at it at any point. Reads clear and easy, very nice product to give you peace of mind.