Health & Safety Consultants

Lincolnshire East Yorkshire North Norfolk, UK& other areas by arrangement.

Health & Safety Consultants

Legionella and the Workplace

Legionella and the Workplace

Managing and monitoring a water system to inhibit Legionella is a legal requirement for every business occupying a commercial premise. Any water system can be susceptible to outbreaks of Legionella bacteria. 

In this blog we will look at the risks and actions that employers, or those in control of premises such as the landlord, can take to manage legionella risks.

The risks of Legionella bacteria

Legionella bacteria can be found in man-made water systems such as hot and cold-water systems, cooling towers and spas as well as natural water sources e.g., lakes, reservoirs, rivers, and streams.

Legionella bacteria can thrive in the following conditions:

  • when water temperatures are between 20-45°C.
  • where nutrients such as rust, sludge, scale, sediment, and algae are present.
  • where water is stagnant in the water system (for example, if a shower or tap is not regularly used)

When Legionella bacteria builds up in a water system, it can lead to the potentially fatal Legionnaires disease. This disease is a serious form of pneumonia that causes inflammation of the small air sacs in the lungs (alveoli) and their associated tissues. The disease is spread via small water droplets. 

The first outbreak of the disease is where its name originates. It was a convention of the American Legion in Philadelphia. At this convention tragically 29 people died. Today, Legionnaires disease still presents a serious risk to people.

Legionella control regulations

Legionella although serious, it is preventable and governments across the world have introduced legislation to govern the management of water systems. In the UK it is the legal duty of anyone responsible for a water system to undertake a legionella risk assessment and put in place measures to deal with any issues identified.

The UK health and safety legislation is:-

The last document in the list above has been developed to help business owners and landlords conform to the legislation and carry out its requirements. 

Legionella control in area with at risk groups

Hospitals and healthcare facilities are a good example of workplaces that have more vulnerable members of the public. At-risk groups include people who are suffering from things such as chronic respiratory disease, diabetes, heart disease, or anyone with an impaired immune system.

For this reason, the regulations regarding Legionella control in hospitals and healthcare facilities are more stringent. The healthcare sector also follow the Department of Health’s guidance: “Safe water in healthcare premises (HTM 04-01)” on Legionella control.

These legal obligations cannot and should not be avoided. Tasks relating to the obligations can be outsourced. In fact, this is a common route for businesses as Legionella risk assessments need to be undertaken by competent, fully-trained assessors. 

Often those working within the business such as facilities managers are not qualified in this specialist area, this could be due to the time investment or cost of the training. Ultimately clear and professional compliance needs to be demonstrated.

Legionella risk assessments and outcomes

Any system that might pose a risk should be subjected to a Legionella risk assessment. According to the HSE this should include critical systems to assess evaporative cooling systems and hot and cold-water systems, along with any other water system that might produce airborne water droplets.

The first area to look at is the system’s infrastructure, with an inspection of obsolete pipework (dead ends) or dead legs. These are areas where water could stagnate and lead to the growth of Legionella bacteria. Where identified, action should be taken to flush (let the water run from outlets) or remove these water traps.

Where pipework or equipment joins is another area of risk - natural rubber, hemp, linseed oil-based jointing compounds and fibre washers have all been identified as potential breeding grounds for bacteria. If any of these are present, they should be replaced with suitable alternatives.

All elements of the system should be inspected for corrosion, scale, sediment and biofouling (accumulation of microorganisms, plants, algae, or small animals on wetted surfaces that have a mechanical function, causing structural or other functional deficiencies). Key places to inspect would typically include cold storage tanks, calorifiers (hot water heaters) and evaporative cooling systems. 

If signs of any of these are found, remedial action should be taken including cleaning and disinfection.

Water services should be operated at temperatures that prevent Legionella growth: -

  1. Hot water storage cylinders (calorifiers) should store water at 60°C or higher.
  2. Hot water should be distributed at 50°C or higher (thermostatic mixer valves need to be fitted as close as possible to outlets, where a scald risk is identified).
  3. Cold water should be stored and distributed below 20°C

If you have five or more employees you have to record any significant findings from the risk assessment, including those identified as being particularly at risk and the steps taken to prevent or control risks.  If you have less than five employees, you do not need to write anything down, although it is useful to keep a written record of what you have done.

On completing the risk assessment if you conclude that there is no reasonably foreseeable risk or the risks are low and are being properly managed to comply with the law, your assessment is complete. You may not need to take any further action at this stage, but any existing controls must be maintained, and the assessment reviewed regularly in case anything changes in your system.

Legionella prevention

The legislation dictates that whoever is carrying out the Legionella risk assessment should be a competent individual with a full understanding of the relevant Codes of Practice. In practice, this means that risk assessments are carried out by an experienced assessor to ensure full compliance with the relevant legislation and a safe water system.

Legionella prevention should be a key priority for anyone responsible for the water systems of any building or facility. Effective Legionella control that complies with the UK regulations can be achieved by working with an experienced and qualified risk assessor, giving you peace of mind and safeguarding your business, your people and your customers.

It’s important to find a provider who can offer a bespoke risk assessment and risk management solution to suit your specific business and its individual requirements. ST Services can help with this, contact us for more information.