Legionella Risk Assessments for Commercial Premises

Legionella is a form of bacteria which grows within hot and cold water systems. Legionella can be caused due to periods of inactivity in water systems when the water is left to stagnate and bacteria is more likely to grow. If a person inhales any water droplets which are contaminated by Legionella, it can cause Legionnaire’s disease, a fatal form of pneumonia.


The approved Code of Practice L8 – The Control of Legionella Bacteria in Water Systems requires an employer, a self-employed person or the person who is in control of a premises to assess the risks from hazardous micro-organisms, including legionella and chemicals such as biocides and chlorine, and adapt appropriate control measures in the follow plant and systems:

  • Water systems incorporating a cooling tower
  • Water systems incorporating an evaporative condenser
  • Hot and cold water systems
  • Other plant and systems containing water which is likely to exceed 20 degrees Celsius and which can release a spray or aerosol during operation or when being maintained or tested, ie. sprinkler systems, humidifiers, air washers, spa baths and pools

Minimising the risk of Legionella

There are a number of ways in which the Person in Control can minimise the risk of exposing persons to Legionella:

  • Monitoring the temperature of water systems (keeping hot water hot, and cold water cold)
  • Regularly keeping water moving throughout the systems
  • Flushing out systems prior to letting the property
  • Ensure fittings are tight to avoid debris getting into the systems
  • Setting control parameters to ensure water is stored and used at correct temperatures
  • Removing any redundant pipework
  • Implementing instantaneous water heaters, such as combi boilers and electric showers, as there is no water storage

The Person in Control should advise persons of any control measures which have been put in place to minimise the risk of Legionella. This can include not adjusting the temperature settings of water systems, cleaning shower heads regularly and informing the Person in Control of any problems with the water or heating systems to enable appropriate actions to be taken.

Stroma Tech Legionella Risk Assessments

Stroma Tech has a team of chartered health and safety consultants, with a vast range of experience in identifying health and safety issues.

We have a detailed and meticulous process for Legionella Risk Assessments and our specialists ensure that your building complies with health and safety guidelines. We undertake physical examinations of the water-systems on the premises before we issue a detailed report with plans and schematics for eliminating risks.

Stroma Tech – nationwide coverage for Legionella Risk Assessments For more information on our services, including how we can improve the health and safety of your building, fill out our quick contact form or contact our team directly on 0845 621 2222.

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