Corentium Canary Radon Detector

I think that's as good as it gets. The safety siren has the same specs only it's a touch cheaper - https://www.safetysirenpro.com/

My understanding is that the Safety siren needs to be re-calibrated each year or it starts to show artificially high readings. (Amazon reviewers)

Whereas the Canary is good for at least ten years before recalibration (Canary website).

OK. The Amazon reviewers would know. I guess the Canary manufacturers use components that are somehow.... better. Either that or the manufacturers of the Siren are somehow.... more up-front? It's hard to know when marketing science comes in to play.

As much as I would love a radon detector, I'll leave buying one until there's a positive, independent review of the Canary, as it's just too much money to take a gamble that it's a good bit of kit.

Well, I saved up my euros and bought a Corentium Canary. A cigarette box sized, Norwegian made, detector of 222-Rn using alpha spectroscopy

The main reason I bought it is that my airfilter is consistently 2 to 3 times above background when I test it in my office, and a pretty hairy 30 times above background in the basement tool shed.

I really think the radon levels in my apartment building are a concern, but I need some kind of proof so that I and other people living in the building can go to the authorities and ask for action to be taken to reduce radon levels.

Obviously I'll post my readings here when I get them.

I know a one day average isn't very accurate at all, so bear that in mind when I say that the one day average for my well-ventilated office is 18 Bq/m3. Incidentally the weather here has been warm, low humidity and no winds in the last 24 hours.

I'm reliably informed that the Canary shows lower than actual readings if the test period is less than a month, but is pretty accurate after that period.

I've now reset and moved the Canary to the tool room in the basement and will let you know the one day average tomorrow. I suspect it will be much higher than 18 Bq/m3