print header


Legionella bacteria are found naturally in the environment, usually in water, including hot water tanks, air conditioning cooling towers, humidifiers, whirlpools, spas, hot tubs and decorative fountains.

You may be exposed to Legionella bacteria if you breathe in small droplets of water in the air that have been contaminated with the bacteria. The bacteria are not spread from person-to-person and you cannot become infected by drinking water containing Legionella bacteria. For more information on the disease see our Legionellosis Fact Sheet and to learn more about Legionella click here.

Statistics have shown that legionella can spread through inadequately maintained cooling towers and evaporative condensers.There is an increased incidence in Legionnaire’s disease in Ontario. Cooling towers are the most common source for the illness. 


Toolkit - Developing a Water Management Program to Reduce Legionella Growth and Spread in Buildings - Centers for Disease Control and Prevention

Guideline 12-2000: Minimizing the Risk of Legionellosis Associated with Building Water Systems - American Society of Heating, Refrigeration and Air-Conditioning Engineers, INC.,

Guideline: Best Practices for Control of Legionella - Cooling Technology Institute, July 2008

Did you find what you were looking for?
What did you like about this page?
How can we improve this page?

If you have any questions or concerns that require a response, please contact Health Connection directly.

Thanks for your feedback.
Failed to submit comment. Please try submitting again or contact us at the Health Unit.
Comment already submitted ...