How could I forget ash fall? I wasn't prepared for that when St. Helens blew. I'm ready now!
How about wildfires on the west coast, oh wait like another pandemic (a prior epidemic is part of why Asia was well prepared) that's in the never ever ever could happen, you made this up category. Wildfires and brush fires, increasing with climate change, I MUST be making things up.

I mean air filters might be slightly more practical, heaven knows that's why I have an air filter, though I use it for other things too.