Controlling Legionella: A Checklist for Businesses

Ensuring a safe water environment in commercial settings is crucial to preventing the spread of Legionella bacteria, a common and potentially dangerous pathogen found in water systems. Legionella thrives in warm, stagnant water, making plumbing systems, cooling towers, hot tubs, and decorative fountains prime breeding grounds. Inhalation of contaminated water droplets through aerosolisation is the primary transmission mode to humans, posing serious health risks.

With professional guidance, your hotel, office, or gym can become Legionella-safe. This guide provides essential information on understanding Legionella, maintaining water systems, and implementing effective control measures to keep your premises protected. Read on for expert tips, regulatory compliance strategies, and practical advice to ensure your water systems are secure and your environment is safe from Legionella contamination.

Understanding Legionella:

Legionella thrives in warm water environments, typically found in plumbing systems, cooling towers, hot tubs, and decorative fountains. Stagnant or poorly maintained water systems provide fertile breeding grounds for Legionella bacteria. Inhalation of contaminated water droplets, particularly through aerosolisation, is the primary mode of transmission to humans. It is never good to discover Legionella in water, but with our help, your hotel, office or gym can be Legionella safe!

Another common breeding ground for Legionella bacteria is shower heads. In a commercial setting and as part of routine Legionella control maintenance, to comply with HSE ACOP L8 and HSG274 Part 2, shower heads and hoses should be dismantled, cleaned, descaled and disinfected on a quarterly basis. Cleaning shower heads for Legionella is simple and well worth it to keep your shower running efficiently overall. Read more about cleaning shower heads on our blog.

For more information, we highly recommend reading up on the .Gov article here.

Top Tips:

1. Conduct a Legionella Risk Assessment (to be carried out by qualified assessor):
   • Identify potential sources of Legionella contamination within your premises.
   • Assess the vulnerability of water systems to Legionella proliferation.
   • Evaluate factors such as water temperature, stagnation, and the presence of biofilms.
   • Use a risk assessment system to help track staff training and knowledge.
2. Implement Water Management Plan:
   • Develop and implement a comprehensive water management plan tailored to your business.
   • Regularly inspect and maintain water systems to prevent stagnation and biofilm formation.
   • Set appropriate temperature parameters for hot water systems (above 50°C) to inhibit Legionella growth.
   • Ensure adequate disinfection measures, such as chlorination or ultraviolet (UV) irradiation, in water systems.
3. Monitor Water Quality:
   • Regularly test water samples for the presence of Legionella bacteria.
   • Establish a monitoring schedule in accordance with regulatory guidelines.
   • Maintain accurate records of water quality testing and remedial actions taken.
4. Educate and Train Staff:
   • Educate employees about the risks associated with Legionella and the importance of preventive measures.
   • Train staff in the proper maintenance and operation of water systems.
   • Foster a culture of awareness and responsibility regarding Legionella control among employees.
5. Control Cooling Towers:
   • Implement stringent maintenance protocols for cooling towers, including regular cleaning and disinfection.
   • Monitor water quality parameters such as pH, biocidal levels, and conductivity.
   • Install drift eliminators and regularise drift eliminator cleaning to minimise aerosolisation of contaminated water.
6. Ensure Proper Ventilation:
   • Maintain adequate ventilation in enclosed spaces to minimise the accumulation of aerosolised water droplets.
   • Inspect and clean ventilation systems regularly to prevent the spread of airborne contaminants.
7. Develop Response Protocols:
   • Establish clear protocols for responding to suspected cases of Legionnaires' disease or Pontiac fever.
   • Promptly investigate any instances of water system contamination and take appropriate remedial actions.
   • Communicate effectively with relevant stakeholders, including employees, customers, and public health authorities.
8. Stay Informed and Updated:
   • Stay abreast of emerging research, regulatory changes, and best practices in Legionella control.
   • Regularly review and update your Legionella control measures in response to new information or guidelines.