Legionella FAQ

Legionnaires' Disease is caused by a bacteria called Legionella

Legionnaires’ Disease is a form of pneumonia caused by breathing in droplets of water contaminated by a specific type of bacteria (Legionella). Most people know the name but are not clear about the facts.

Q: How do I catch it?

A: You cannot catch it by drinking water. You can catch it by breathing it into your lungs.

Q: Does all water contain it?

A: No, it occurs in natural water sources like rivers. Your mains water supply is treated to control bacteria, so your water tap is very likely to be safe. STORED hot and cold water between “certain temperatures” can contain it.

Q: Between what “certain temperatures”?

A: The bacteria grow between 20°C and 45°C. Your hot water thermostat should be set to 60°C so that the water reaches your taps above 50°C. Please be careful – this is very hot, and you could scald yourself. Your cold water should feel really cold - much colder than room temperature.

Q: Who is most at risk of catching it?

A: Older adults, the very young, smokers and those with chest or lung problems or weak immune systems. If you are undergoing treatment that weakens your immune system (like chemotherapy) or suffer an autoimmune disorder (like Ulcerative Colitis) you must take extra care. If in doubt ALWAYS consult your GP.

Q: How can I reduce the risk of catching it?

A: Through good hygiene and by taking care. Make sure to run any little-used or unused water taps and showers on a weekly basis (turn on for three minutes). Keep taps and water outlets free from limescale – especially inside the spout of taps. Be sure to descale showerheads at least once every three months. When returning from holiday, run all of your taps and showers gently for three minutes and flush your toilets a few times with the lid down. Here’s some information about how to manage limescale in your home.

Please remember not to adjust the temperature of your calorifier (hot water cylinders) and if you have problems with your hot water system please call Smith & Byford on 0800 917 8335.

Q: What are the symptoms?

A: It’s like Flu – with symptoms including high temperature, headache, muscle pains, fever, chill, coughing, shortness of breath and chest pains.

Q: What should I do if I think I have it?

A: Don’t panic – make an appointment to see your doctor. You are highly unlikely to catch it, especially in the winter months when the water in your tank is usually a lot colder than 20°C. We will look after and treat all communal cold water tanks, but your personal hot and cold water in your property is your responsibility. If your doctor diagnoses that you have Legionnaires' Disease please inform us immediately 

Further advice is available on the Health and Safety Executive (HSE) website: www.hse.gov.uk/legionnaires