Chris Nancrede Presented on Chemical-Free Approaches to Controlling Legionella Growth at Legionella 2026

Chris Nancrede, EIT, ASSE 12080, presented at Legionella 2026, the 11th International Conference on Legionella, held September 7–11 at the University of Zurich in Switzerland. The audience included representatives from the CDC, noted Legionella researcher Janet Stout, and other Legionella experts from around the world.

Chris presented “Two Chemical-Free Approaches to Controlling Legionella Growth in Building Water Systems: Dissolved Oxygen Reduction and Charged-Membrane Filtration.” The presentation focused on emerging approaches to waterborne pathogen control that do not depend on adding oxidizing chemicals to the building water system.

One approach uses membrane technology to reduce dissolved oxygen in circulating hot water systems, making conditions less favorable for Legionella growth. The second uses charged-membrane filtration at the building water entrance to capture Legionella and other microorganisms before they enter the plumbing system.

Chris also discussed how these technologies can fit alongside more established Legionella control and secondary disinfection approaches, including UV, filtration, and chemical treatment. Different technologies address different parts of the problem, making a layered approach to Legionella control important for many facilities.

Presenting at Legionella 2026 gave Chris the opportunity to share these engineering approaches directly with many of the researchers and professionals helping shape Legionella prevention and control around the world.