Skip to Main Content

What is Legionella, and How to Prevent Legionella Contamination



It’s a hot topic when Legionella contamination turns up in apartment buildings, seniors’ homes and other facilities. But what is legionella? And does it really present a risk?


What is Legionella?

Legionella is a form of bacteria that grows in water and can lead to Legionnaires’ disease (also known as legionellosis) – a severe form of pneumonia.


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.


How we can help

At LuminUltra, we specialize in helping to identify and manage microbes in water systems of all types. Contact us today to find out more about what solutions we can offer to you.


Stacey Pineau

Clearly explaining complex topics has been Stacey’s focus for close to 25 years now. She helps plan how best to reach the right people, then works to provide them with relevant information that’s easy to understand. Stacey is a team player with an entrepreneurial spirit. She has broad experience that spans the private and public sectors. A lover of words, Stacey has a slightly irrational love of the library and a personal collection of way too many books and magazines. She lives in Fredericton with her husband Ray, their two children and dog Scouty.

Related Posts

Water vs. Climate Change

  Recently, the United Nations held a conference in Morocco related to climate change issues. The location of the conference had significant meaning because Africa has become a bellwether for the rest of the world when it comes to climate change. Desertification and rising sea levels both impact countries all over that continent. Water scarcity… Read More

Most Wanted Microbes – Legionella

  From the editor: This is the fifth post in an ongoing series profiling microorganisms of particular significance in water and wastewater systems. In this series we will cover microorganisms of many types including some that are beneficial, inhibitory and pathogenic. Legionella is a mesophilic, pathogenic organism that can cause Legionnaire’s Disease, a potentially fatal… Read More

Interesting water tech innovations from around the world

  There have been some interesting happenings in the water technology industry in recent weeks. As companies around the world work to solve water problems of one sort or another, some truly inventive ideas come to light. Here’s a quick rundown of some particularly interesting developments we’ve come across: In Switzerland, robotics company EPFL Biorob… Read More

Your browser is out of date!

Update your browser to view this website correctly. Update my browser now