There was a time when my air quality sensor (a Temtop device) showed suspiciously high PM2.5 in the kitchen. It turned out the kitchen oven had too much oil bui

There was a time when my air quality sensor (a Temtop device) showed suspiciously high PM2.5 in the kitchen. It turned out the kitchen oven had too much oil build up inside and required cleaning. And no, I tried both cheap and expensive air purifiers; none of them could beat opening the kitchen window or turning on the range hood (a dedicated one, not the kind attached to a microwave). In this particular case, it was also a good reminder to clean the oven.