Water Hygiene

Domestic hot and cold water systems can provide an environment where legionella bacteria can grow. Legionnaires’ disease can be caused by the inhalation of small droplets of contaminated water containing legionella bacteria. Residents of rented domestic accommodation should follow the below guidelines to minimise the risk of contracting legionnaires’ disease within their home.

What is Legionnaire’s disease?

Legionnaire’s disease is one of a number of illnesses caused by the legionella bacteria. Legionnaires disease is a potentially fatal form of pneumonia, which can affect anybody. It is caused by the inhalation of small droplets of water from contaminated sources containing legionella bacteria.

Who is at risk?

• People over 45 years of age
• Smokers and heavy drinkers
• People suffering from chronic respiratory or kidney disease; and,
• Anyone with an impaired immune system.

The symptoms of Legionnaire’s disease are similar to those of flu including high temperature, fever or chills, headache, tiredness, muscle pain or dry cough.

Where is Legionella found?

The legionella bacterium occurs naturally and can be found in lakes, rivers and soils etc. From the natural source, the organism passes into sites that constitute an artificial reservoir (piped water in towns and cities, water networks, water systems in individual buildings). Water temperatures in the range of 20°C to 45°C favour the growth of legionella bacteria. The organisms do not appear to multiply below 20°C and are killed within a few minutes at temperatures above 60°C.

Conditions ripe for colonisation where water of between 20°C and 45°C stagnates, and where there is sludge, rust and scale present.

What precautions can I take?

Most importantly, make sure that:

• Hot water in the system is kept hot
• Cold water is kept cold
• The water is kept circulated and moving.

Taking the following simple precautions will help keep you safe:

• Flush showers and taps for 10 minutes following a period of non-use (i.e. after you have been on holiday or if a room is not in regular use). Remove the shower from the holder before turning on the shower, and hold the shower head close to the plug hole to reduce the spray
• Keep all shower heads and taps clean and free from a build-up of limescale, and mould. Shower heads should be cleaned and disinfected every 3 months
• Do not adjust the settings on the boiler or hot water system. Keep hot water tanks and your boiler at a temperature of 60°C or greaterWARNING: Be aware of scalding!
• Report any deposits such as rust or any unusual matter flowing from your water outlets
• Report any changes in the colour of your water.

These are very simple steps to help protect you in your home and minimise any exposure risk. These precautions are even more important if you are over 50 years of age or suffer from ill health.

Tell us if:

The cold water is still running warm after you have initially run off any water which may have accumulated in the pipes. It should not be above 20°C.

There are any problems, debris or discolouration in the water.

The boiler or hot water tank is not working properly, particularly if the water is not coming out of the taps at a sufficiently high temperature. It should come out at a temperature of 50°C after it has run for at least one minute.