North Organic Vapor & Acid Gas cartridges are available for 5400, 5500, 7600 and 7700 respirators. When properly fitted these cartridges protect against Organic Vapors, Chlorine, Hydrogen Chloride, Sulfur Dioxide, Hydrogen Sulfide (Escape Only), Hydrogen Fluoride and Chlorine Dioxide. The addition of a P100 prefilter adds protection against all particulates.