This invention is in the field of systems and methods for controlling contamination in high purity environments. This invention relates generally to particulate filtering and treatment of molecular contamination and process gases in enclosures, such as cleanrooms, contamination controlled manufacturing environments, mini-environments, isolators, glove boxes and restricted air barrier systems (RABS). The invention is capable of chemically transforming molecular contamination and process gases into less reactive or inert reaction products while at the same time decreasing the level of biological and nonbiological particulates.