DBNPA-20 is a class of non-oxidizing biocides used to control microbial special biocides in reverse osmosis membrane systems. DBNPA-20 reverse osmosis special fungicide is a fast-acting broad-spectrum fungicide. For reverse osmosis membrane desalination systems that utilize industrial wastewater, seawater, and other surface waters containing microbial sources as a source of water, biocontamination of membrane fouling is a ubiquitous problem. The incompatibility of chlorine gas and other oxidizing biocides commonly used in water treatment with polyamide reverse osmosis limits the use of such bactericides.