Legionella is the bacterium that causes Legionnaire’s disease. It is naturally found in water but can multiply and become dangerous in water systems. It grows best in warm water, making hot water systems the most vulnerable to infection.
Legionnaire’s disease is a potentially fatal form of pneumonia that can be developed following exposure to dangerous levels of the legionella bacterium.
Legionnaire’s disease can be contracted through exposure to dangerous levels of the legionella bacterium in water. It is contracted by breathing in vapour or small droplets rather than through drinking it or other forms of ingestion. Therefore any system that heats water or creates spray is particularly at risk.
Those over 50 or very young, smokers or former smokers, those with lung conditions and those with a compromised immune system are most at risk of contracting Legionnaire’s disease.
Legionella control is the process of managing the risk of legionella and maintaining safe water systems.
All businesses and organisations need to take steps to control the risk of legionella in their buildings and environments. It applies to any organisation that has some kind of water system including toilets, washing facilities and dish washing/laundry facilities. Because of the way Legionnaire’s disease is contracted via breathing in water vapour, premises with showers, spas/saunas, sprays and swimming pools are particularly at risk and need to monitor their systems carefully.
A legionella risk assessment must be carried out by someone competent to do so. They don’t necessarily have to be qualified, and it will depend on the nature of your organisation and its facilities, but you do need to understand exactly what you are looking for, have an understanding of water systems, be able to identify whether the component parts of your system are likely to create a risk and a number of other technical details.

If you don’t have such a person within your organisation, you will need to outsource the task to someone who does have the skills and knowledge. Our risk assessors are qualified and very experienced and because this is all they do, they are also very efficient and able to put very effective systems in place which makes the monitoring process that goes with it, much simpler for you to administer.

Legionnaire’s disease is contracted by breathing in water vapour, therefore any water systems that creates small water droplets, steam or vapour are particularly at risk. This would include showers, hot water systems, spas/saunas, spray irrigation systems, dish washing, laundry or swimming facilities. Hotels, leisure centres, hotels and buildings of multiple occupancy are therefore considered high risk.
This can depend on a number of factors, such as the nature and scale of your organisation, the number of people within it, the types of water systems that you have etc. A risk assessment should be conducted regularly, with consistent monitoring undertaken in between. A change in the system, such as a new installation or repair, would certainly trigger the need for a new risk assessment. We can advise you on how often would be appropriate for your organisation.
Thermostatic Mixer Vales, or TMVs, offer scald protection by allowing hot and cold water to be blended rather than running the hot water system at a reduced temperature. While providing water at a safer temperature, the mixed water downstream of a TMV does provide an environment in which the Legionella bacteria can potentially thrive therefore this needs to be managed.
TMVs can be useful on any hot water system but they are particularly important in environments where there are vulnerable people such as children, the sick and the elderly. Therefore schools, care homes and hospitals need to make use of TMVs in their premises.
An RPZ (Reduced Pressure Zone) valve is a cost effective type of backflow protection device that prevents water flowing back into the system from where it came. Backflow can happen when there is a reduction of pressure and it can suck contaminated water back into the drinking water supply.

Backflow poses one of the biggest risks of contamination to the mains water supply.

Back flow represents a significant danger to water safety because contaminated water can re-enter the mains water supply.
An RPZ (Reduced Pressure Zone) valve is the best way to prevent backflow. It allows water to flow through one way but not to re-enter in the event of a reduction in pressure.
You need to comply with the standards detailed in Approved Code of Practice (ACoP) L8 and Water Supply (Water Quality) Regulations 2010. The best way to do this is by conducting risk assessments, establishing a proper compliance maintenance system and undertaking necessary remedial work as and when required. An electronic compliance system such as Zeta Safe makes management much more efficient and easy to stay on top of.
You have a duty to comply with the Approved Code of Practice (ACoP) L8 as imposed by the Health & Safety at Work Act 1974. This sets out your responsibilities in terms of the standards you must meet and how you go about managing this through risk assessment, monitoring, remedial works and management of your compliance systems.
The potential consequences of not conducting proper legionella risk assessments range from HSE conducting checks and fining you, to being responsible for the death of someone contracting Legionnaire’s disease. There are a range of outcomes that fall between the two extremes, such as having your business closed down, suffering a loss of reputation should you failure to adhere to health and safety standards become public or expensive remedial works because you’ve allowed the issues to go unchecked and become worse. None of these scenarios are worth risking when risk assessments and water compliance systems don’t have to be difficult if you choose the right provider to work with.
A legionella risk assessment is very important because it gives you reassurance on the areas where there’s no cause for concern and flags potential issues where there is with plenty of time to take remedial action. It’s also a legal requirement to comply with the Approved Code of Practice (ACoP) L8 as imposed by the Health & Safety at Work Act 1974
It’s a legal requirement to comply with the Approved Code of Practice (ACoP) L8 as imposed by the Health & Safety at Work Act 1974 and Water Supply (Water Quality) Regulations 2010.