ASHRAE, a non-profit technical society headquartered in Atlanta, has developed resources to help reduce the risk of Legionella, including Standard 188, which provides a comprehensive approach to help prevent the growth and spread of Legionella within building water systems.

“With the recent outbreak of Legionnaires’ disease in Atlanta, we would like to increase awareness of the resources available to help minimize health risks associated with building water systems,” says Darryl K. Boyce, P. Eng, 2019-20 ASHRAE President.

The CDC estimates approximately 6,100 cases of Legionnaires’ disease in the United States each year. Most of those cases result from exposure to Legionella found in building water systems.

ASHRAE has also reached out to the Fulton County Board of Health and the Georgia Department of Public Health to make these government offices aware of ASHRAE resources.

In 2018, ASHRAE published a revised edition of Standard 188, which designers and building operators can use to help establish water management plans specific to the systems in particular buildings, campuses or health care facilities. Guideline 12, Minimizing the Risk of Legionellosis Associated with Building Water Systems, is currently in revision and provides more detailed descriptions of best practices.

“By creating a framework for proactively managing building water systems and reducing the potential for Legionella growth in these systems, following Standard 188 can help building and facility managers prevent many but not all cases of legionellosis,” says Boyce.

The 2018 edition of Standard 188 provides:

  • A description of environmental conditions that promote the growth of Legionella, such as water temperature fluctuations, water pressure changes and water stagnation.
  • Minimum Legionellosis risk management requirements for buildings and associated potable and non-potable water systems.
  • Requirements for Legionellosis control strategies and documentation.
  • Clarification of compliance requirements, as well as an update to enforceable, code-intended language to facilitate adoption of the standard for code and regulatory purposes.