Comment by nerdsniper

Actually, just a normal <$10 N95 [0][1] (without an exhalation valve). But they won't stop chemicals, just particles. My family have found they prevent COVID transmission from masked sick members to unmasked family members, as well as from unmasked sick members to masked family members.

0: https://www.3m.com/3M/en_US/p/d/b00038112/

1: https://www.3m.com/3M/en_US/p/d/b00037933/