A Legionella risk assessment is a vital health and safety procedure that both protects you, your business, and everyone who uses your facilities. Businesses and building owners in the UK are legally required to have them done regularly, as the risks of neglecting them can be severe.

The assessment takes the form of a survey and report provided by the assessor that details the areas of your site that pose a threat of legionella. During the process, your risk assessor will pay close attention to any areas where water is stored, accessed, and where aerosols can form.

In order to pinpoint the conditions that cause Legionella to grow in water systems, the entire building must be evaluated. Spray systems, warm or stagnant water, or unsanitary conditions are all areas of high concern for this. To be safe and thorough, it’s necessary to investigate all possible sources of water.

Usually, it will be possible to complete the survey within a few hours, and the process should not interfere with normal business operations. After the survey results are analysed, a report is produced which provides recommendations for remedial actions to prevent, minimise, and control Legionella. This ensures the building is safe for occupants to use. 

It’s important that this report is periodically reviewed. This should be done whenever circumstances change, such as when changes have been made to the water system, the use of the building, or legislation.

This risk assessment is the process that keeps us and our water safe.

What is Legionella?

 Legionella is a harmful bacterium which can grow in water and moist soil. It has the risk of appearing in water systems that are not properly maintained and checked.

If debris or germs accumulate in water systems are  left unchecked, or when water is not stored at safe temperatures, legionella bacteria can rapidly multiply. Since legionella will thrive in water around 20-50°c, systems such as heating tanks, hot tubs, and showers are all particularly at risk.

This bacteria carries a lot of danger; Legionella can cause Legionnaires disease, and may lead to severe health implications if someone is afflicted.

A person contracts Legionnaire’s disease by inhaling small droplets of water in the air that contain the bacteria. When people inhale water droplets or aerosols containing these bacteria, they may become very ill, so it’s important to be cautious.

How It Spreads

Legionella in water systems can cause contamination when it grows and multiplies, which can result in small droplets that people can breathe in. These airborne droplets of water containing Legionella bacteria cause Legionnaires’ disease when they enter the lungs.

In rare cases, Legionnaires’ disease can be contracted by drinking water containing Legionella. Some of the water people drink gets breathed into their lungs and causes them to become ill.

Keeping cold water below 20°C, and hot water above 60°C helps mitigate the risk of bacteria growth. It is also important to be aware of infrequently used areas of the water system, since they may be places where water may collect and stagnate, which is a breeding ground for bacteria.

The risk of Legionnaires Disease

This infection of the lungs is usually more severe than normal pneumonia. Many people infected with Legionella may believe they just have the flu when they are in fact suffering from a potentially dangerous illness.

Legionnaires’ disease usually manifests itself after two to fourteen days after exposure to Legionella bacteria. This time period is referred to as the incubation period.  

There are several symptoms to look out for, including:

  • A fever above 40°c
  • A chill
  • Coughing, occasionally coughing up blood or mucus

Healthy people rarely contract severe Legionnaires’ disease, but those with weakened immune systems may suffer life-threatening consequences. People over 50 years of age, those undergoing medical treatment such as chemotherapy, and those with chronic diseases like diabetes are at most risk.

Unfortunately, Legionnaires’ can be very dangerous, and around 1 in 10 who contract it will die as a result. 

What happens in a legionella risk assessment?

During a legionella risk assessment, a nonintrusive survey of the water system is performed to locate areas where legionella is at risk of growing. These areas may include water tanks, sprinklers, showers, spas, and infrequently used taps.

As part of the process, the assessor can also review previous assessments and management procedures to determine whether the recommendations made in them have been implemented. Any risks evaluated will be compared to a standard list of criteria to ensure consistency and high standards. 

You’ll receive a report after the assessment, usually digital, which is designed to help you implement a safer water strategy. It’s commonly advised to replace sections of your water system that are no longer suitable for their purpose, or to flush water through inactive parts of the system to prevent stagnant water collecting.

Why you need them

Preventing the disease from occurring and spreading is always preferable to treating it when it appears. This means monitoring and maintaining all water systems in buildings and other areas.

Legionella Risk Assessments are the first step toward implementing a water treatment and hygiene programme. It is the building operator’s legal responsibility to conduct or engage qualified personnel to do so.

In order to comply with the Health and Safety Executives ACoP L8 guidance and the Health and Safety at Work Act 1974, you must regularly be assessing your legionella risk and carrying out any recommendations given.  

The responsibility to maintain safe water systems falls to landlords, building owners, and managers. A system of control should be developed to manage this process. If appropriate steps aren’t taken to ensure the water system is safe, the responsible parties may face prosecution if an outbreak occurs.

Who can Do a Legionella Risk Assessment?

Only if you have the necessary expertise as a building owner, manager, or landlord can you conduct a legionella risk assessment. This is an area of risk assessment where, for the sake of health and safety, you must be knowledgeable.

If the site is large or has complex water systems, legionella testing is more complicated. If you lack the appropriate skills, expertise, or knowledge to execute a complete job, you should hire a professional. However, to conduct a legionella risk assessment in most household situations, no specific expertise is required.

The person undertaking the evaluation simply has to be ‘competent’ to do it.

Competency indicates that a person is knowledgeable about health and safety standards enough to carry out the survey safely, and in depth. 

They should also have the necessary experience to give recommendations for healthy water system maintenance. 

If the building owner or operator is not knowledgeable enough to do the risk assessment themselves, it’s good practice to employ an expert who can guarantee that all of these areas are covered.

What Glacier can do to help 

Water treatment and hygiene expert Glacier Environmental Ltd specialises in preventing, identifying, and mitigating Legionnaires’ disease. We provide water system control and maintenance services across the UK.

Our company employs a specialised workforce for the management of Legionnaires’ disease. All of our personnel are trained in accordance with the Legionella Control Association training matrix. This ensures we have the right skills and qualifications for the job.

You can be sure that your tests are carried out to the highest quality. Our work is in line with the latest ISO 9001 standards. We’re members of The Legionella Control Association, and we’re also involved in CHAS, Safe Contractor, and The Water Management Society. 

At Glacier Environmental ltd. We are committed to technology, innovation, and improvements to working practices.
Contact us today to find out how we can help you protect against legionella.