Defender™ Multi-Purpose Cartridge and P100 Particulate Filter: NIOSH approved for use against Organic Vapor, Ammonia, Methylamine, Formaldehyde and Acid Gas (Chlorine, Hydrogen Chloride, Sulfur Dioxide, Hydrogen Sulfide, Hydrogen Fluoride, Chlorine Dioxde) with a P100 particulate filter (99.97% minimum filter efficiency) for all particulates.