IKEA VINSTYRKA air quality monitors

I have two of these. One upstairs and one in the basement.

Note the VOC jumping from around 60 to right at 500 in the period of a few minutes. Both the upstairs and downstairs monitors detected a large increase in VOC around the same time.

I wouldn’t say it was a glitch because both do taper off over time rather than going back to around 60 in a few minutes.

Vapors from a poltergeist?

Cooking with gas? Can produce large amounts VOCs.

Or flatulent poltergeist?

Copied from elsewhere:
You need to read the sensor PDF where it explains how the voc sensor works. The numbers it reports are not absolute in any way. They explain it's like a human nose where you can get used to a smell, but if it's worse or better, you notice. It has a baseline that it calculates from the previous 24hrs and that is 100. If it get's better, the number is lower, if it gets worse, the number goes higher (up to 500). But 100 in my house isn't the same as 100 in your house. If you had a perfectly sealed box and put one of these in it, according to their docs, it should report 100 constantly. You could put it in super clean air and after a day it would 100, you could put it in with swamp gas and all sorts of awful ■■■■ and after a day it would report 100 (again, according to how their docs describe how it functions). So it's really only useful for determining if things are better or worse than usual, with usual being the previous day.