Rocky Mountain Bee Supply's Respiratory Safety Kit is heavily recommended when treating with oxalic acid.
3M P100 / OV / AG Multi-Purpose Reusable Respirator 62023, Medium Size, NIOSH-APPROVED P100 / Organic Vapor / Acid Gas Rated Filters, Adjustable Head Straps, Comfortable & Lightweight. Recommended for use with oxalic acidsublimators or vaporizers to protect the beekeeper from inhaling oxalic acid vapors while treating bee hives for the varroa destructor mites.