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What is Legionella?

Legionella is a form of bacteria that can lead to Legionellosis disease. Legionella bacteria grow in water and can cause two types of illness in humans- Pontiac fever and Legionnaires’ disease.

Legionnaires' disease is a serious illness. It’s characterized by a lung infection (pneumonia), which can be quite severe and result in hospitalization.

Pontiac fever is the milder form that is characterized by symptoms that resemble the flu.

  • Tips

    Reducing the temperature of your NB Power water heater below 60°C (140°F) can create a safety risk to you and your family. It's factory set to 60°C to keep your family safe.

    If you think your hot water is below this temperature, please call us at 1 800 663-6272.

saftey at 60safe zone

What temperature does legionella thrive in?

Optimal growth of legionella bacteria occurs at temperatures between 20°C (68°F) and 50°C (122°F). For more information on the cause and prevention of Legionnaires’ disease visit the World Health Organization at www.who.int

Who's at risk?

Although the risk of getting Legionnaires’ disease is generally quite low, anyone exposed to the bacteria can become infected. Individuals with weakened immune systems, certain chronic diseases, smokers, elderly and individuals working with certain water systems are at greater risk of developing the disease.

How can i reduce my risk?

Safety at 60°C - the required temperature for safe, reliable hot water.

Regular cleaning, disinfection and maintenance of mist producing devices like showerheads, humidifiers and hot tubs will also reduce your risk.

Use distilled water in respiratory therapy devices and clean regularly, especially when used with children, the elderly and people with medical conditions.

Why do i need to keep it at 60°c?

The National Plumbing Code, CSA and the World Health Organization have set a mandate that water heaters used in Canada come factory set at 60°C (140°F) to reduce the risk of bacterial growth and potentially legionella in electric water heaters. 60°C

Water heater safety tips

With your water heater’s thermostats pre-set at 60°C (140°F), burns can occur within seconds. Scalding is a serious concern when using hot water, especially for children, the elderly and people with medical conditions. If you need to reduce the water’s temperature at the point of use, please contact a licensed plumber to discuss options such as mixing valves or tempering devices.


Safety at 60°C - The required temperature for safe, reliable hot water.

The National Plumbing Code, CSA and the World Health Organization have set a mandate that water heaters used in Canada come factory set at 60°C (140°F) to reduce the risk of bacterial growth and potentially legionella in electric water heaters. Download our Legionella brochure to learn more.