Author here. I'm planning to do some more comparison testing of PM modules and planning to benchmark modules from Sensirion, Plantower, Cubic and AlphaSense. Let me know if you know some other sensor modules that could be interesting. I think this could be a pretty interesting follow up post.
no one should worry about CO₂ at all in their homes or offices. only workers in certain industries/factories, where CO₂ can get several orders of magnitude higher, need to be concerned at all about it. you (here and in your marketing materials) are stoking needless anxiety over a gas that life on earth literally requires.
pollutants, on the other hand, and particularly particulate matter (especially chemicals that we've manufactured recently in human history), do have proven negative health consequences and should be monitored and mitigated in the home and office. it's estimated that over a million people a year die prematurely of respiratory and cardiovascular complications due to pollution.
in short, a lack of CO₂ monitoring in favor of PM and VOCs by ikea should be seen as a plus, not a minus here.
I thought cheap instruments usually estimated CO2 from a MOS TVOC sensor.
In any case, for automation purposes, CO2 sensing is extremely useful. Regardless of whether you think indoor CO2 directly causes cognitive performance issues or is a proxy for other things that cause those issues (the issues themselves are well documented), indoor CO2 is an excellent measure for the fraction of indoor air consisting of exhaled air, which is a good thing to use for automated demand controlled ventilation.
Not at all. The majority of studies have found a notable decline in cognitive ability starting somewhere around the 800-1,200 ppm range. Due to increasing insulation/energy standards/etc, modern homes have poor air exchange and levels will often get that high or higher unless a window is opened. I have seen quite a few reports of people seeing levels exceeding 2,000 at night, and multiple studies showing that many multifamily/efficiency homes would easily get over that 1,000 ppm mark.