A non-oxidizing biocide is a chemical used to control bacteria, algae, fungi, and slime-forming microorganisms without killing by oxidation. Common examples- Glutaraldehyde- Isothiazolinones (e.g., MIT, CMIT)- DBNPA (2,2-dibromo-3-nitrilopropionamide)- Quaternary ammonium compounds (“quats”)- THPS (tetrakis(hydroxymethyl)phosphonium sulfate) Typical uses- Cooling water systems- Industrial process water- Oil and gas systems- Pulp and paper- Metalworking fluids- Paints and coatings How they differ from oxidizing biocides- Oxidizing biocides: chlorine, bromine, chlorine dioxide, ozone, peroxide-based products- Non-oxidizing biocides: act by disrupting cell function, enzymes, membranes, or DNA rather than oxidizing cell components Advantages- Often more selective- Useful where oxidizers would damage equipment or products- Can be effective against biofilms when properly applied Considerations- Can still be hazardous and require proper handling- Microbes may develop resistance if overused- Selection depends on water chemistry, pH, temperature, and system typeIf you want, I can also give you:1. a list by industry, 2. a comparison table vs oxidizing biocides, or 3. recommended non-oxidizing biocides for cooling towers / oilfield / wastewater.