A new standard for design guidance on legionellosis is currently available from ASHRAE, formerly known as the American Society of Heating, Refrigerating and Air-Conditioning Engineers. ANSI/ASHRAE Standard 188-2015, Legionellosis: Risk Management for Building Water Systems, sets minimum legionellosis-risk-management requirements for water systems.
ASHRAE developed the standard in response to the 8,000 to 10,000 cases of Legionnaires’ disease reported each year in the U.S. More than 10% of those cases are fatal, says Tom Watson, chair of the ASHRAE committee that wrote the standard. Legionella can also cause a less-severe influenza-like illness known as Pontiac Fever.