HSE Legionella Risk Assessment: Your Essential Guide from Zeta

As duty holders responsible for managing water systems in various premises, from commercial buildings and healthcare facilities to residential blocks and industrial sites, the threat of Legionnaires’ disease is a serious concern. At Zeta, we understand the complexities involved in maintaining water hygiene and ensuring compliance with vital health and safety regulations. A cornerstone of this compliance in the UK is the HSE Legionella Risk Assessment.

You might have heard the term, but what exactly does it entail, and why is it so crucial?

The Legal Imperative: Your Duty of Care

Firstly, let’s establish the “why.” The Health and Safety at Work etc Act 1974 places a general duty of care on employers and those in control of premises to ensure, so far as is reasonably practicable, the health, safety, and welfare of their employees and others who may be affected by their work activities.

More specifically, the Control of Substances Hazardous to Health (COSHH) Regulations 2002 include biological agents, for example, Legionella bacteria. This means that if you operate a water system where there’s a reasonably foreseeable risk of exposure to Legionella, you are legally required to identify and assess that risk.

The Health and Safety Executive (HSE) provides clear guidance through their Approved Code of Practice (ACOP) and guidance document L8, “Legionnaires’ disease: The control of Legionella bacteria in water systems.” This document provides detailed advice on how to comply with the law regarding Legionella.

HSE Legionella Risk Assessment Explained

A sample Legionella Risk Assessment is not just a tick-box exercise; it’s a systematic and thorough examination of your water systems to identify and evaluate the risk of Legionella bacteria growth and dissemination. Carried out by a competent person (which Zeta prides itself on providing), it forms the foundation of your Legionella control strategy.

The assessment typically involves:

• Identifying Potential Sources of Risk: This is the initial step, where the assessor meticulously surveys all water systems on your premises. This can include:
• Hot and cold water systems (tanks, pipework, outlets, calorifiers)
• Cooling towers
• Evaporative condensers
• Spa pools, jacuzzis, and hot tubs
• Decorative water features
• Mains water-fed systems (e.g., showers, toilets, kitchens)
• Process water systems

Assessing the Likelihood of Legionella Growth: For each identified water system, the assessor evaluates factors that encourage Legionella proliferation. These include:

Temperature: Water temperatures between 20°C and 45°C are ideal for Legionella growth. Stagnant cold water or hot water that isn’t hot enough is a prime risk.

Stagnation: Areas of low or no flow within a system can allow water to sit and bacteria to multiply.

Nutrient Availability: The presence of scale, rust, sludge, sediment, and biofilm (a slimy layer of microorganisms) provides food and shelter for Legionella.

Aerosol Generation: Any system that creates fine water droplets (aerosols), such as showers, cooling towers, or even hosepipes, can potentially disperse Legionella bacteria into the air, which can then be inhaled.

Susceptible Individuals: Identifying who might be exposed (e.g., employees, residents, patients, visitors) and if any are particularly vulnerable (e.g., elderly, those with respiratory conditions, or compromised immune systems).

Evaluating Existing Control Measures: The assessment will examine any current measures you have in place to control Legionella, such as temperature regimes, cleaning schedules, or chemical treatments, to determine their effectiveness.

Recommending Control Measures and Management Plan: Based on the identified risks, the assessment will provide clear, actionable recommendations to eliminate or control them. This forms the basis of your Legionella Written Scheme of Control, outlining:

• System modifications (e.g., removing dead legs, ensuring proper insulation)
• Temperature control regimes (e.g., maintaining hot water above 50°C/60°C in healthcare, cold water below 20°C)
• Cleaning and disinfection schedules
• Monitoring and testing frequencies (e.g., temperature checks, water sampling)
• Roles and responsibilities for managing the water system
• Record-keeping requirements

Why Choose Zeta Compared To Other Legionella Risk Assessment Companies?

At Zeta, we provide comprehensive sample Legionella risk assessments conducted by highly trained and experienced assessors. We understand the nuances of ACOP L8 and BS 8580-1:2019, ensuring your assessment is:

Competent: Our assessors possess the necessary qualifications, knowledge, and practical experience.

Thorough: We leave no stone unturned, meticulously inspecting every aspect of your water system.

Practical: Our recommendations are realistic, cost-effective, and tailored to your specific site and operations.

Compliant: We help you meet your legal obligations, safeguarding both your occupants and your business.

Remember, an HSE Legionella Risk Assessment is not a one-off event. It’s the critical starting point for an ongoing journey of monitoring, maintenance, and review. By partnering with Zeta, you gain a trusted expert to guide you through this process, ensuring your water systems are safe and compliant, protecting everyone under your roof. 

Call us today at 01869 326000 for your Legionella Risk Assessment.