Senseair is a Swedish company and definitely not "cheap Chinese crap". Do you know about any research that confirms your statements about the accuracy?

I believe that some of the more expensive sensors are more accurate, but this cheap one may be a good enough solution in some cases (e.g. indoor air monitoring for DIY projects).

The research has been done by the weed growing community. I don't know any professional growers using sensors outside of the American Scientific as the cheap ones are inaccurate and failure prone.

Thanks for sharing. I wanted to get Winsen MH-Z19B, but Senseair S8 (residential) looks like a better, more reliable option, for a DIY project. One comparison: https://www.letscontrolit.com/forum/viewtopic.php?t=3736&sta...

If you'd asked me a few days ago I'd have said that the MH-Z19B is okay on a budget but now that I know you can get an S8-0053 for $20, I don't think I can recommend it.

If it's difficult for you to get the cheap S8s for some reason though, per that thread it looks like an MH-Z19B with calibration off is a decent choice.

Yes, Prism is great. Most of the blogs cramp the code in width, I let it spread it's wings full width.

The fan inside the PMS7003 sensor is very quiet.

Netatmo only measures CO2 and depending on your location it would be more useful to know about particulate matter in the air.

I have the same experience - Xiaomi makes good and cheap hardware, but the software and reliability are bad. And if you want to keep your data private, skip them.

Is it linux or freebsd based? Can the firmware be reflashed?

I can just confirm what others are saying here - Java is great for the development of robust and reliable software. If you need even lower memory usage, you can compile the Java app with a GraalVM to a native image.

RuuviTag is a sensor capable of measuring the temperature, relative air humidity, and atmospheric pressure and sending the data over Bluetooth. I wrote about it in a linked article - https://joshefin.xyz/temperature-humidity-pressure-with-ruuv...

If your air purifier has a screen and shows the air quality, it's most probably using a PM sensor like the one I write about here.

How accurate is PMS7003? If for example, you need to know the precise and exact concentration of particulate matter in the air - then currently available low-cost PM sensors are not to be considered accurate. But, if you need to know if the air quality in your home is good, fair, moderate, poor or very poor, then it's good enough.

These sensors also need calibration every week or so, which basically involves opening the windows to feed fresh air.

You can use the PM measurement that the sensor outputs to calculate the Air Quality Index (for Europe: http://airindex.eea.europa.eu/) and for example, make it send you a notification when the pollution level goes up, so you can turn on the air purifier or vacuum or open the windows.