Monitoring reverse osmosis performance: Conductivity versus fluorescence excitation-emission matrix (EEM)

► Consistent dissolved organic matter (DOM) rejection in RO measured by fluorescence. ► Novel leak detection more sensitively compared to conductivity profiling. ► Verified molecular weight dependent rejection up to high molecular weight. ► DOM rejection >99.9% measured by size exclusion chromatography. ► DOM proposed as pathogen surrogate for operational monitoring of membrane integrity.