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NSF 444 Standard Will Help Prevent Legionella Outbreaks


Legionellosis is a respiratory disease caused by Legionella bacteria. Sometimes the bacteria cause a serious type of pneumonia (lung infection) called Legionnaires’ disease. The bacteria can also cause a less serious infection called Pontiac fever that has symptoms similar to a mild case of the flu. Unfortunately, Legionella bacteria make frequent appearances in hotels. Legionella was discovered after an outbreak in 1976 among people who went to a Philadelphia convention of the American Legion. The convention took place at the Bellevue-Stratford Hotel and 34 people died. Last year there was an outbreak of Legionnaires’ Disease in New York City that left 12 dead and more than 100 infected. Part of the outbreak traced back to a hotel and there was a cooling tower connection. The CDC estimates that between 8,000 and 18,000 people are hospitalized with Legionnaires’ disease in the United States each year, with more than 4,500 cases reported in 2014.

To address concerns about legionellosis, global public health organization NSF International and ASHRAE have signed a memorandum of understanding (MOU) to jointly develop NSF 444: Prevention of Injury and Disease Associated with Building Water Systems. Water quality often degrades once water enters buildings, and it could expose occupants to hazards such as microbial pathogens, toxic chemicals and physical hazards. NSF 444 seeks to provide a methodology for the systematic analysis of building water systems and the application of control measures necessary to prevent harm and to maintain public health.

“The development of NSF 444 and this MOU with ASHRAE represent NSF International’s commitment to helping assure water quality in areas that impact human health,” said Jessica Evans, Director of Standards at NSF International. “NSF 444 is the first NSF standard to address building water quality and our working relationship with ASHRAE will help us contribute expertise to this important area of the water quality industry.”

U.S. public health and environmental organizations at the state and federal levels, members of ASHRAE, private healthcare systems, academia and those in the water industry are participating on the joint committee to develop the standard. The standard is expected to be released in 2017.

Continue to watch Green Lodging News for updates on NSF 444.