Jonathan 3 The TVOC value is always the same for a given CO2 value (I got the exact same value as the ones in the pictures sent by other people)The CO2 value seems random (it is at the lowest - 400, and suddenly when there is air blowing it will skyrocket and be stuck there for a while displaying random variations and will go back to 400 after rebooting the device)The CO2 value raise when I blow on the device (which is expected) but it will also raise when I put it in the blow of my air purifier at home. Seems like it just reads the wind intensityThe humidity level is much lower than the one recorded on my other devicesOnly the temperature seems ok