Water systems are essential to many workplaces and commercial properties, but they also need careful management. Where water is stored, circulated, or allowed to remain stagnant, there may be conditions that allow Legionella bacteria to grow.
A Legionella risk assessment helps dutyholders understand these risks and put suitable control measures in place. It is an important part of protecting employees, residents, visitors, and other people who may be exposed to a property’s water system.
What Is Legionella?
Legionella is a type of bacteria that can grow in certain water systems. People can become exposed by breathing in small droplets of contaminated water, often called aerosols. These droplets may be produced by systems and outlets such as showers, taps, spa pools, cooling systems, and some other water equipment.
Legionella can cause Legionnaires’ disease, a serious form of pneumonia. The level of risk depends on the type of water system, how it is used, whether water can stagnate, and who may be exposed.
The aim is not simply to identify whether Legionella is present. It is to assess the system and manage the conditions that could allow bacteria to multiply or spread.
Who Is Responsible for Managing the Risk?
In the UK, the dutyholder is generally the person who has control of the premises or responsibility for health and safety. This may be an employer, landlord, facilities manager, building owner, or managing agent, depending on the property and arrangements in place.
The Health and Safety Executive states that dutyholders need to identify and assess sources of risk, prepare and implement a control scheme, appoint a responsible person, and keep appropriate records. Its Legionella control guidance provides further information on these duties.
The responsible person should have suitable knowledge, authority, and support to ensure that control measures are carried out properly. They do not need to complete every task personally, but they should understand the system and oversee the arrangements.
What Does a Risk Assessment Involve?
A Legionella risk assessment reviews a property’s water system and identifies factors that may increase the chance of bacterial growth or exposure. The level of detail should reflect the complexity of the system.
A professional Legionella Risk Assessment can help property managers understand their water system, identify areas of concern, and establish practical control measures.
An assessment may consider:
- Sources of hot and cold water
- Water storage tanks and pipework
- Showers, taps, and other outlets
- Dead legs or rarely used pipework
- Areas where water may stagnate
- Temperature control arrangements
- The condition and cleanliness of the system
- Whether occupants may be more vulnerable to infection
- Existing monitoring, inspection, and maintenance records
The findings should be recorded clearly and used to create or update a control scheme.
Common Control Measures
Control measures will vary according to the property and its water system. A small office with basic hot and cold water services will not have the same requirements as a hotel, care home, leisure facility, or large apartment block.
Common measures may include keeping water at appropriate temperatures, flushing infrequently used outlets, removing redundant pipework, cleaning and maintaining tanks, and monitoring the system according to the control scheme.
It is important not to treat a risk assessment as a one-off document. The assessment should be reviewed regularly and whenever there is a significant change, such as alterations to the water system, changes in building use, prolonged periods of low occupancy, or evidence that existing controls are not effective.
Why Record-Keeping Is Important
Accurate records show that control measures have been planned, completed, and checked. They can also help the responsible person identify patterns, missed tasks, or areas that need further attention.
Useful records may include the risk assessment, details of the appointed responsible person, temperature monitoring, flushing schedules, inspection reports, cleaning and disinfection activities, and any remedial work completed.
Good record-keeping supports a more organised approach to water safety and makes it easier to demonstrate that the system is being actively managed.
FAQ
Is a Legionella risk assessment required for every business?
Dutyholders must assess and control the risk of exposure to Legionella in their premises. The assessment should be proportionate to the type and complexity of the water system.
How often should a Legionella risk assessment be reviewed?
There is no single review period that applies to every property. It should be reviewed regularly and when there are significant changes to the water system, occupancy, building use, or control measures.
Can a small property have a Legionella risk?
Yes. The risk depends on the water system and how it is managed, not only on the size of the property. Simple systems may have lower risks, but they still need appropriate assessment and control.
Who should complete a Legionella risk assessment?
The assessment should be completed by someone who is competent to identify risks and recommend suitable controls. This may be an appropriately trained in-house person or an external specialist.
Conclusion
A Legionella risk assessment is an essential part of responsible property management. By understanding the water system, appointing a responsible person, maintaining clear records, and reviewing control measures when circumstances change, dutyholders can take practical steps to reduce risk and protect the people who use their premises.
