• Legionella, legionnaire's disease, legionellosis, infectious diseases, healthcare in hospitals, waterborne pathogens

About Legionella

Legionella bacteria grows in warm water and can commonly be found in cooling tower reservoirs and in domestic water systems, especially where heated water is present. When Legionella grows, and Legionella-containing water aerosols are inhaled, susceptible individuals (such as older adults and/or the immunocompromised) can develop Legionnaires’ disease.

Legionella bacteria control includes water temperature control and continuous or intermittent chemical treatment of aerosol-producing sources, such as cooling towers, whirlpool spas, misters, fountains, and showers. Techniques that can help prevent the proliferation of the bacteria include designing out points of stagnation in water systems, preventing plumbing contamination during construction, and flushing new or modified plumbing systems with chemicals prior to occupancy.

FACS has assisted managers and owners of hospitals, hotels, and high-rise buildings in the identification and prevention of Legionella growth. We can also document levels of Legionella in water sources and respond rapidly and effectively to actual or alleged Legionella outbreaks.

The Centers for Disease Control and Prevention have provided a free practical guide to implementing industry standards. It includes a yes/no worksheet to help you determine whether or not your building needs a water management program.

New Changes in the Standard of Care

During the past two years, there has been movement toward a fundamental change in the standard of care for prevention of Legionella-related illness lead by private, public and government entities.  This stems from the need to proactively manage Legionella outbreaks as opposed to taking a reactionary stance. The change has increased pressure upon commercial entities ­– particularly those in healthcare and hospitality enterprises – to either become active in preventative efforts, or face increased risk of occupant illness and potential litigation.

Supporting this changed stance is a new framework affecting the certification of professionals engaged in identifying, and remediating, sources of waterborne bacterial outbreaks.

Resources Include:

Authored with the assistance of multiple FACS experts including David Krause, PHD, CIH.

Guidelines for Recognition, Evaluation and Control of Legionella

American Industrial Hygiene Association (AIHA) | Paid, May 2015


ASHRAE-188 Guidelines – Minimizing the Risk of Legionella Associated with Building Water Systems

American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) | Paid, June 2015


Developing a Water Management Program to Reduce Legionella Growth and Spread in Buildings: A Practical Guide to Implementing Industry Standards)

CDC | Free, November 2015