Water hygiene (Legionnaires')

Protect your home

Legionnaire's disease is a form of pneumonia caused by the Legionella bacteria.

There is a small risk that Legionella may arise in your home, but there are a number of steps you can take to protect yourself.

When you move into your home, or where it is left unoccupied for more than one week, be sure to:

  • run all showers, baths, wash basins and sinks continuously for five minutes to flush through any form of bacteria
  • switch your water heater on (if possible) and leave for one hour before use
  • dismantle, clean and descale shower heads and hoses regularly

Please note: raising the temperature of warm water is one way to control Legionella growth, but could also increase the risk of burns and scalding, especially if you have children.


About the Legionella bacteria

Legionella are bacteria common in natural rivers and lakes. Legionella is also found in artificial water systems such as:

  • hot and cold water systems
  • storage tanks
  • pipe work
  • taps
  • showers

Other potential sources of Legionella include:

  • spa and whirlpool baths
  • humidifiers
  • drinking water systems
  • water features
  • garden hoses
  • sprinklers
  • fire fighting systems – sprinklers and hose reels

Those most at risk include elderly people, smokers, and those suffering from long-term illness.

Legionella bacteria can survive in low temperatures, but thrive at temperatures between 20ºC and 45ºC. Temperatures above 50ºC will kill the bacteria.

The infection is caused by the inhalation of water droplets or spray mists, which have been contaminated by the bacteria,

It is not contracted through drinking contaminated water and cannot be passed from person to person.