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Legionella Risk Assessment London: Everything you need to know.

If you own a business or property in London, you must ensure that you have a legionella risk assessment carried out regularly. Legionella is a type of bacteria that can cause Legionnaires’ disease, which is a potentially fatal form of pneumonia. In this blog post, we’ll look at why legionella risk assessments are so critical and how often you need to have them carried out.

What Is Legionnaires’ Disease?

Before we go any further, it’s essential to understand what Legionnaires’ disease is and how it’s caused. Legionnaires’ disease is a form of pneumonia that can sometimes be fatal. It’s caused by the legionella bacteria, which is found in water droplets, such as those produced by showers, taps, hot tubs, and heating systems.

When people inhale aerosolized droplets containing Legionellae, they become infected. The bacteria multiply inside the cells lining the lungs, causing pneumonia. Symptoms include fever, chills, muscle aches, headaches, cough, and shortness of breath. Sometimes, it can also lead to vomiting, diarrhoea, and confusion. Most people recover after two weeks, but some people develop severe complications such as kidney failure or even death. If you experience any of these symptoms, you should seek medical help immediately.

Why Are Legionella Risk Assessments Important?

Legionella risk assessments are critical because they identify any potential sources of legionella bacteria in your property or workplace. Once these sources have been identified, they can be removed or treated to minimise the risk of exposure to the bacteria.

How Often Should I Have A Legionella Risk Assessment?

The frequency of your legionella risk assessments will depend on several factors, such as the size of your property or workplace and the number of people who work or live there. However, as a general rule of thumb, you should have a risk assessment carried out at least once a year.


Legionella Risk Assessment London: FAQs

1. Where can Legionella bacteria grow?

Legionella bacteria can be found in freshwater bodies such as lakes, reservoirs, rivers, and streams. They can, however, be found in man-made water systems such as hot and cold water systems, cooling towers, and spas.

Any natural or man-made water system, given the right combination of environmental conditions, has the potential to become a breeding ground for Legionella growth.

Legionella bacteria pose significant health risks in areas where water is stored or recirculated and where breathable water droplets may be spread in the form of aerosols.

2. What factors encourage the growth of Legionella bacteria?

Temperatures of 20-45°C (77-113°F)

Locations ready to supply nutrients (sludge, organic matter, algae, scale, rust, etc.)

Surface biofilm on water

Poor water management and a lack of training and awareness programmes.

3. What external factors can promote the growth of Legionella bacteria?

Stagnation of water

The temperature of the water

Fluctuations in municipal water quality Fluctuations in water temperature

pH variations in scale and sediment

Inadequate disinfectant levels in construction

4. When should a Legionella Risk Assessment (LRA) be performed?

If you are a building manager, landlord, or employer, it is critical that you understand the Legionella health risks and conduct a Legionella risk assessment.

The old "industry standard" recommended a Legionella risk assessment at least every two years. On the other hand, the Approved Code of Practice L8 (ACoP L8) recommends that arrangements be made to review the LRA "when there is reason to suspect it is no longer valid" so that the assessment is always up to date.

This is especially important when building occupants are classified as high-risk (the elderly, for example), as an assessment may need to be performed more frequently.

It is critical to conduct an LRA whenever there is a change:

A change in the use of the building that houses the specific water system

A change in the water system itself A change in key personnel within the company A shift from unoccupied to occupied

A revision to relevant legislation

When a case of Legionnaires' disease has been reported

5. What is the Legionella risk assessment process?

A Legionella Risk Assessment will include a review of your current records and previous assessments to ensure that all remedial work or maintenance recommendations have been followed.

A Legionella risk assessment should consist of two steps. A physical inspection and consultation with everyone involved in bacterial control, including verifying management procedures and paperwork, should occur.

The first part of the Legionella risk assessment will include a review of your current records and previous assessments to ensure that all remedial work or maintenance recommendations have been followed.

The second part of the assessment will include a tour of the site, with a particular emphasis on areas where water is stored or where aerosol