Special Pathogens Laboratory sets the industry standard for Legionella control through our introduction and evaluation of disinfection technologies. Since the early 1990s, we have tested all major Legionella disinfection technologies used in the field and continue to explore new technologies. Our findings are published in peer-reviewed scientific and medical journals. We use a step-wise evaluation criteria for determining the efficacy of disinfection methods. 

Following are disinfection technologies shown to effectively reduce the presence of Legionella in water systems:


Monochloramine has been used successfully for municipal water treatment. Now a commercial system for treatment of single buildings has been developed by Sanipur (Brescia, Italy). Dr. Stout presented findings of the first U.S. study of this monochloramine generating system for Legionella disinfection at the annual Association of Water Technologies conference in September 2012. The results showed a significant decrease in Legionella percent positivity of the hospital's hot water system soon after installation.

 Evaluation of a New Monochloramine Generation System for Controlling Legionella in Building Hot Water Systems    

Copper-Silver Ionization

Copper and silver ions are bactericidal against Legionella and other waterborne pathogens. A study by Dr. Janet E. Stout and Dr. Victor L. Yu, published in Infection Control and Hospital Epidemiology, documents that copper-silver ionization significantly reduced Legionella in hot water distribution systems of 16 hospitals, and reduced or eliminated cases of hospital-acquired Legionnaires' disease.

Experiences of the First 16 Hospitals Using Copper-Silver Ionization for Legionella Control: Implications for the Evaluation of Other Disinfection Modalities  

Chlorine Dioxide

Research conducted by Special Pathogens Laboratory showed that Legionella can be successfully controlled by chlorine dioxide. The time needed to achieve requisite reduction in percent positivity is site specific and dependent on whether the application point is on the cold water, hot water or a combination.

 Legionella Control by Chlorine Dioxide in Hospitals   

Point-of-Use Filters

Special Pathogens Laboratory and others have shown in independent studies that Point-of-Use (POU) filters prevent exposure to waterborne pathogens from faucets, showers and ice machines. These pathogens include Legionella, Pseudomonas and Mycobacteria.

Efficacy of new point-of-use water filter for preventing exposure to Legionella and waterborne bacteria    

Ultraviolet Light

Research by Special Pathogens Laboratory showed that focal disinfection with UV light could reduce Legionella in a hospital when combined with a systemic disinfection method.

Legionella in Water Distribution Systems