What is Legionella?
Legionella is a type of bacteria that can cause Legionnaires' Disease, a serious form of pneumonia. It commonly thrives in water systems like cooling towers, ornamental fountains, and plumbing systems.
How do people contract Legionnaires' Disease?
People contract Legionnaires' Disease when they inhale small droplets of water contaminated with Legionella bacteria. Those most at risk include individuals over 65, smokers, former smokers, and people with weakened immune systems.
Which water systems pose the highest risk for Legionella?
Cooling towers, evaporative condensers, and ornamental fountains pose the highest risk for Legionella growth and exposure.
What is a Water Management Program, and do we need one?
A Water Management Program identifies and manages potential Legionella risks. According to ASHRAE and NSF guidelines, any facility with cooling towers or centralized potable hot water systems should have a water management program in place.
How often should we test cooling towers for Legionella?
Cooling towers should be tested quarterly if operated year-round, or at least three to four times during the May to November operating season, with tests conducted shortly after system startup.
How frequently should cooling towers be cleaned?
OSHA recommends cleaning cooling towers twice a year. Practically, performing one professional cleaning annually, preferably just before seasonal startup, is sufficient.
Why should we use professional cleaning services for cooling towers?
Professional cleaning ensures thorough and effective removal of contaminants, following best practices outlined by the Association of Water Technologies (AWT). Using certified contractors helps maintain compliance and reduces health risks.
What chemicals are required for proper cooling tower maintenance?
Cooling towers require a dual-biocide program, including one oxidizing and one non-oxidizing biocide. These biocides can be fed continuously at low concentrations or periodically in higher doses, based on your facility's needs.
What should we do if we notice unusual water events?
Report any unusual water conditions, such as brown water due to hydrant maintenance or construction, immediately to facility management. These events may indicate bacterial contamination requiring further assessment.
How can we minimize Legionella risk during plumbing shutdowns?
Plumbing systems unused for extended periods pose increased Legionella risks. Any plumbing system that has been dormant should undergo proper flushing and disinfection before reuse, especially showers and other aerosol-generating fixtures.
Should our facility have a water usage map?
Yes, having a detailed water usage diagram identifying where water travels and its applications within your facility is crucial for effective Legionella risk management and compliance.