Legionella Disinfection Methods, Treatments and Solutions

Why Should You Disinfect Legionella?

There are two main reasons why Legionella disinfection is important: safety and legal compliance.

Firstly, Legionella bacteria pose a health risk to building occupants. They grow in water that sits at temperatures between 20˚C and 45˚C, and can be dispersed in water vapour and inhaled. They can then lead to the development of Legionnaires’ disease, which is a potentially severe form of pneumonia. Research from Public Health England suggests that there are around 4,000 to 6,000 cases of Legionnaires’ disease in the UK every year, and it kills between 7% and 12% of those it infects.

Because of the health risks, there are strict water hygiene guidelines which govern the control of Legionella growth in water systems as well as the methods for disinfection. These include HSG274 and BS 8558:2015. It is vital that employers, property managers and those with health and safety responsibilities (duty holders) meet their obligations to protect building occupants.

What is the Best Method to Kill Legionella Bacteria?

As we have discussed, there is a range of methods for how to treat Legionella in water. The right one for you will depend on your system and building usage.

Employers, landlords and building managers are legally responsible for controlling Legionella in their water systems in accordance with ACOP L8. A Legionella risk assessment should form the basis of your control programme, and will help you identify risk areas, necessary remdial work and, if necessary, the correct Legionella treatment method.

The best way to determine the right solution for you is to speak with an expert water hygiene consultancy or your risk assessment provider. They can advise on the best Legionella compliance method for your premises.

Will the Legionella Disinfection Treatment Disrupt Day-to-Day Business?

Some methods of Legionella disinfection will be more disruptive than others. If your system simply requires simple long-term prevention methods such as heat disinfection, then you should experience minimal disruption if any at all.

However, if you are advised to install more complex systems, such as UV treatment or chlorine dosing, then a little more disruption might be caused while these are fitted. Although a dependable Legionella consultant should be able to advise on timelines as well as work with you to minimise any disruption.

The best way to determine the right solution for you is to speak with an expert water hygiene consultancy or your risk assessment provider. They can advise on the best Legionella compliance method for your premises.

Who Should Carry Out Legionella Disinfection?

Legionella disinfection is a scientific process that should be carried out by someone who is competent, trained and has the equipment and understanding necessary to ensure effective treatment as well as monitor the outcomes.

This most often takes the form of a water hygiene consultancy such as EMS, which has a wealth of expertise as well as a team of highly trained specialists on hand to provide everything from Legionella risk assessments to ongoing treatment and monitoring services.

What Records Need to Be Kept After the Water Disinfection?

The HSE requires that thorough records be kept of all actions taken to control Legionella, and that these are available for inspection if needed. So, to remain compliant, you should obtain and keep records of Legionella disinfection. Your treatment provider should give you documentation regarding the type of disinfection used, concentrations of any chemicals and the date on which the treatment took place.