> “The general go-to clean room/industrial filter stack is Prefilter(F5 Bag)->HEPA->Activated Carbon.”
yup, i bought a blueair 211+ (https://www.blueair.com/us/blue/blue-pure-211/1695.html), that has exactly those filter elements in a nice (if bigger than expected) package. this model was recommended by both consumer reports and the wirecutter (until recently, cynically thinking they didn’t pay wirecutter’s “endorsement fees”). it’s effectively eliminated my constant coughing, sneezing and runny noses before i got it.