Legionella Risk Assessment London

Legionella risk assessments LondonLegionella is a type of bacteria that is associated with water systems. If the bacteria becomes airborne (in water spray, mist or vapour) it can be inhaled by people and have the potential to cause a range of pneumonia-like illnesses. The infection is caused by breathing in the small droplets of water contaminated with the bacteria. However, the disease cannot be passed from one person to another.

In London, outbreaks of Legionella disease are rare. However, you can dispel them entirely in your home or work environment when you put detailed risk assessments in place to ensure that every potential risk is identified and being managed in the best possible way.

Where does it come from?

Outbreaks of legionella are common in natural water systems where the water is maintained at a temperature high enough to encourage growth of the disease. This bacterium is water-borne and causes three predominantly fatal diseases which are collectively known as Legionellosis. Legionnaires’ Disease is a potentially fatal form of pneumonia and typically affects men more than women.

Risk Assessments

In London, Risk Assessments are performed within certain situations where Health and Safety Laws advise it is sensible to do so. They are done to help reduce the risks associated with a wide variety of situations, particularly in the workplace. They can also be used to identify risks associated with Legionella bacteria and the likelihood of this bacteria affecting one or more people.

It is sensible with all water systems that they are reviewed regularly to make sure nothing has been missed or changed. In regard to Legionella, sometimes changes to the building, its use, or even the water systems could affect changes to the results– requiring a new assessment to be made to ensure the safety of everyone. If you do not keep your risk assessment up to date, you put others at risk and allow the bacteria to multiply and spread as a result.

Below, we will inform you how best to complete a thorough check. Read on to find out more.

Identify the Hazards

A risk assessment is designed to identify any building that has water sources or uses water systems and the potential risks associated with the legionella bacteria to ensure no one is at risk of harm. The first step of a Legionella assessment is to identify any hazards. Hazards are potential sources of risk. When identifying hazards linked to legionella, you need to identify whether:

  • Water is stored or recirculated regularly.
  • The water temperature is between 20–45 °C.
  • Conditions would encourage bacteria to multiply.
  • There are sources of nutrients such as rust, sludge, scale and organic matters.

Decide Who Might Be Harmed

For each hazard you discover, you need to be clear about who might be harmed as it will help you to identify the most effective course of action. In any location, there will be people who are more vulnerable than others, such as people with disabilities, children, pregnant women and the elderly.

Keep Records

Whenever you partake in completing a risk assessment, you must write everything down. Not only is this helpful for monitoring but it is essential when the review time comes around. A record should always be kept of identifiable hazards and their control measures, plus a description of the water system present.

These records should be retained for at least two years and, if you are a landlord, you must retain records of any monitoring, inspections, tests or checks carried out, and their dates, for at least five years.

Managing the Risk

It is important that the risk of legionella is managed through the appropriate checks and regular health and safety duties. You must take full responsibility for controlling any identified risk from exposure to legionella bacteria and be responsible for the overall risk management of the system.


It is recommended that they are reviewed annually, plus each time changes are made or additional information comes to light. It is important to review the assessment periodically in case anything changes. Appropriate checks can be made by carrying out inspections of the water system when undertaking mandatory visits such as gas safety checks or routine maintenance visits.


There are many places in London where Legionella can be a risk and where risk assessments must be in place to avoid this problem causing sickness to anyone. Any buildings or companies that host groups of people are prone to risk. Below is a list of some of the most common places assessments must be carried out.

For Dentists

dental surgery legionella risk assessmentsAll dental surgeries must uphold an exemplary standard of hygiene at all times. Quite simply, there is no room for complacency in dentistry. The aim of any Legionella assessment in a dental surgery is to identify and assess any sources of known risk of Legionella growth such as low water usage, temperature problems and use of inappropriate materials. All dental practices are required to undertake a written assessment of their hot and cold water plumbing to ensure that hygiene standards are being met and there are no evident risks to anyone.

For Education

Due to the nature of educational settings, it is common that a natural risk will be present simply due to the substantial volume of stored water. The Department of Education are combating this problem and have written a guide aimed at local authorities giving advice on standards for school premises, this includes guidance on water systems and problems with Legionella . Read more about it here.

For Care Homes

As you would expect, the risk of legionella infection in residential nursing and care homes is by nature increased because it is common for the elderly to have a lower immune system than most and, therefore, be more susceptible to illness. The combination of old age and lowered immune systems substantially increases the risk of contracting disease. Therefore, the risk of contracting Legionella in a nursing or care home environment is increased and the importance for care homes to implement suitable control measures cannot be emphasised enough.

For Doctors

In the UK, all doctors’ surgeries and healthcare premises are required by law to have a written scheme together with a Legionella risk assessment to help control any risks. Health and Safety as well as hygiene standards are of ultimate importance when discussing Doctors surgeries. Risk assessments of all kinds should be especially thorough in doctors’ surgeries to help keep patients safe and healthy.

For Swimming Pools

swimming pool leisure facilities legionellaSwimming pools have always had a reputation for carrying germs and posing hygiene risks to their users. Swimming pools are a recognised source of diseases caused by infectious agents that include the organism that causes Legionella disease. There have been a number of Legionella outbreaks linked to spa-pool systems in leisure centres, hotels, on-board cruise ships and in holiday homes.

However, if risk assessments are carried out regularly in said areas, the risk of infection will be greatly reduced. HSE’s guide The Control of Legionella and other infectious agents in spa-pool systems, produced in consultation with Public Health England, and local authority and industry representatives, will help managers and operators assess and control the risk of exposure in swimming pools.

For Estate Agents

Domestic properties are considered ‘low risk’ in terms of Legionella . However, Health and Safety legislation requires that landlords carry out risk assessments for the Legionella bacteria and thereafter maintain control measures to minimise the risk to their potential tenants. Most domestic properties will be low risk but it is essential landlords carry out assessments to ensure that nothing is wrong. Provided the assessment shows that the risks are insignificant and the control measures are being properly managed, no further action will be required. However, it is important that assessments are reviewed periodically, particularly if anything changes in or around the building.


We serve customers all over London who suspect they may have a problem with Legionella and want to get rid of it completely. Our Legionella control service is designed to keep Legionella problems under control and prevent any spreading of this disease.