What is Legionella?
Where is Legionella found?
Building systems where Legionella bacteria can grow and spread include large plumbing systems, hot water tanks, and heaters and hot tubs. Factors that contribute to the bacteria’s proliferation include aging infrastructure, poor plumbing maintenance, and a warm, humid climate, with some researchers wondering if climate change is also part of the problem.
How do people get Legionnaires’ Disease?
Usually, people are exposed to Legionella when they breathe in small droplets of water containing the bacteria. Most healthy people who are exposed to Legionella bacteria don’t get sick. It’s more likely that Legionnaires’ Disease will affect elderly individuals or those with weakened immune systems or underlying illnesses.
How do I assess the risk?
Are you wondering if your building might be at risk for Legionella contamination? You can do a self-assessment quiz as a starting point. You’ll find more information in this guide from the Centers for Disease Control (CDC). The CDC also offers free online training to help you prevent Legionnaires’ Disease through the use of water safety practices.
How can I stay safe?
Canada‘s National Plumbing Code, Canadian Standards Association (CSA) and the World Health Organization have set a mandate that water heaters come factory set at 60°C (140°F). This reduces the risk of bacterial growth including Legionella in electric water heaters. Ensuring proper plumbing system maintenance and regularly cleaning, disinfecting and maintaining mist-producing devices like humidifiers and hot tubs also helps.
What else can I do?
Put a water management program in place for any water system you’re responsible for managing. Following a set program will ensure you have processes in place that prevent conditions that allow Legionella to grow and spread. You can consider routine environmental sampling for Legionella as part of your program. If your testing finds Legionella in a water sample from your system, you will need to decide how and when to respond. It might be enough to adjust temperature levels or flush the pipes, or additional action might be needed.