That's why fresh air is key. Crack a window or two open. Buy an air monitor that monitors CO2 (good proxy for overall freshness), VOCs (sometimes these build up much faster than CO2), and PM2.5.
If CO2 or VOCs are high, open windows more. If PM2.5 is high and coming from outdoors, turn on an air filter.
Yes, this means your heating and cooling bill will be a bit higher. But for your health and concentration, it's worth it.
I mostly solve any issues with VOC by "Stosslueften", but if that's not enough because the air quality outside is too bad, a CR box is an effective, easy to build and almost perfectly silent design, especially if you do it with decent quality pc fans.
My problem with this advice is not that it's difficult to measure pollution levels (it really isn't), but that there's no "fresh air" outside for many of us. In many parts of the world, the air is significantly worse outside than inside even without running an air purifier (and with a purifier the difference in particulate levels can run into 100× or more during winter).
Some years ago I looked at the few papers that measured the difference in gaseous pollutants (like NO2 and SO2) inside and outside with windows open and windows closed, and for some reason closed windows do provide limited protection against them. Nobody really understands why AFAIK, it shouldn't work that way since they're mixed with air in a gaseous mixture from which they can't be filtered out without a specialized chemical filter, but it does help.
The bigger challenge is with my windows open, my heating just can't even keep up! It'll be maxed out and only 18c.
I do the German-style luften twice a day, but if our interiors are just absorbing the compounds and releasing it when the windows are shut, then that's not even going to help much.
2rsf•1h ago
One unclear point for example is what happens with the deposited toxins, how hard is it to clean them? are they transferred by touch?