Legionella

What is it and why do I need to know about it?

16 July 2020

Legionnaires’ diseases is a rare but serious disease caused by Legionella bacteria within the water system and is a form of pneumonia which can be fatal. People can catch legionella disease by inhaling small water droplets suspended in the air which contain the bacteria.

Anyone can get the infection although the risk increases with age and some other factors such as:

  • Being over 45 years old

  • Smoking

  • People with a vulnerable immune system

  • People with conditions such as chronic respiratory or kidney disease, diabetes, lung and heart disease


The bacteria are commonly found in natural sources such as rivers and ponds, although people don’t usually catch it from these sources as the conditions aren’t right for the disease to develop.

However, water systems for our homes can provide the right conditions for the bacteria to develop which is why it is important that you understand what Legionella is howe we can control it.

So, let’s start with our responsibilities as your landlord:

We employ specialist contractors to manage our water for communal water systems. We follow an Approved Code of Practice and monitor these properties on a monthly basis except those properties deemed to be a low risk, namely our domestic general needs properties.

During gas safety checks our qualified engineers will also make sure your boiler is set to the correct temperature 60°C.

So what is a high risk or low risk property?

Our sheltered schemes and those properties where water is provided from a communal system, are are viewed as a high risk because customers at these schemes are likely to fall into one of the above vulnerable categories.

Properties that have their water provided by a communal system are also deemed as a high risk due to the volume of stored water that is required to feed this type of system.

Low risk properties include our general needs properties where the systems are much smaller so the water usage will be higher, meaning the risk is lowered as fresh water is being constantly introduced into the system.

What should I be doing?

If you have a water storage tank in the loft, make sure it has a lid with no holes and is secured tightly to the tank

If you have a cylinder which provides your hot water, make sure the thermostat is set to 60°C. But be careful as this means water from your taps or shower will be very hot, so take care when running water.

If you have a boiler which provides your hot water, make sure your digital display on the boiler is set to 60°C. This will be checked annually during your gas service but is good practice for you to check regularly to make sure the system is working correctly.

Make sure your taps and any shower heads are clear of limescale. This is really important as the scale is a source of nutrients  for the bacteria which can help it grow and multiply. Supermarkets sell descaling products to help with this, especially for hard water areas. We would advise that descaling should take place as regularly as required but carried out at a minimum of every three months.

All taps and showers (not forgetting any outside taps) are likely to be used for several minutes each week. But any taps that arent used that often will need to be flushed through once a week to make sure fresh water is available.

If you are away from home for a week or longer then you will need to flush through all hot and cold taps and showers (not forgetting any outside taps) before use when you return. For any hot taps, turn the hot water back on and leave for two hours to get up to temperature before running it.

You’ve said to flush through taps or showers not used, do I just turn on my taps then?

Well simply put yes but for safety you should:

Turn on the tap slowly and increase the flow of water gradually allowing the water, both hot and cold to run for a minimum of two minutes.

With showers, where possible remove the shower head and let the water flow from the hose, running for a minimum of one minute on the coldest setting and two on the hottest setting.

If your shower head is fixed, cover them with a plastic bag, cutting a small hole in the bottom corner to allow the water to drain out.

What should I do if I have any concerns about Legionella?

We're not here to scare you but just let you know about potential risks and give you the help you need to lower the risk to you and your family.

If you have any questons or concerns then please get in touch with us.