The legionella bacteria can cause a pneumonia-like illness called Legionnaires’ disease.

Although we take precautions on legionella being present in hot or cold water systems in
homes, you have an important part to play in preventing this nasty disease.

Who’s at risk?

Everyone’s susceptible to infection however some people are at higher risk including:
People over 45 years of age
Smokers and heaving drinkers
People suffering from chronic respiratory or kidney disease
Anyone with an impaired immune system.

Where is it found?

Legionella bacteria is in the natural environment and may contaminate and grow in water systems including hot and cold water systems in our homes. The bacteria survive low temperatures and thrive at temperatures between 20-45°C if conditions are right. They are killed by high temperatures at 60°C or above. Domestic hot and cold water systems can provide an environment where legionella bacteria can grow. Legionnaires’ disease can be caused by inhaling small droplets of contaminated water containing legionella bacteria.

What should I do?

Follow these guidelines to minimise the risk of Legionnaires’ disease in your home. Most importantly, make sure that:

  • Hot water is kept hot
  • Cold water is kept cold
  • The water you use is circulated.


Contact us if the boiler or hot water tank in your home isn’t working properly – especially if water is not coming out of the taps at a high enough temperature. It should come out at a temperature of 50°C after it has run for a minute at the latest.

  • Do not interfere with the settings on your boiler or hot water system. The hot water system should be set so that water is heated up to 60°C.
  • Tell us if cold water is still running warm after you have run off any water which may have gathered in pipes.
  • Cold water should not be above 20°C.
  • Tell us if there’s debris or discolouration in the water or any other problems that you’re concerned about.

If your shower is used only occasionally then flush it through by running the water for at least 2 minutes once a week. As far as possible, keep out of the way whilst this is being done.

Also clean the shower head periodically and descale and disinfect it. This should be done at least every three months. box run taps for 2 minutes when you come back from a break when you take a holiday or are away from home for any time, make sure that you run all hot and cold water taps
for 2 minutes when you return.