Purafil, the leader in molecular filtration since 1969. Purafil technologies are trusted worldwide, protecting even the most sensitive environments. — NASA cleanrooms, the Sistine Chapel, the Smithsonian Institute and more. PuraWard technology goes beyond the trapping of particles and aerosols carrying viruses and bacteria. Using a microtechnology containing an EPA-registered antimicrobial additive, the PuraWard filter is protected from many viruses, bacteria, and mold using copper and silver.