On yesterday's walk I've noticed a column of smoke, apparently from a waste-treatment plant that caught on fire: https://news.err.ee/1608986420/waste-treatment-center-catches-fire-on-tallinn-s-suur-sojamae-tanav
> »Hazardous materials are burning, there have been quite a few explosions at the scene and the fire is spreading fast…«
I got a Blue indoor air purifier (mostly as a COVID-precaution) a couple months ago, and did not expect to have to use it against dangerous fumes of fire this fast
(I'm exaggerating of course, we are safe, and the apartment ventillation has its own filters as well)