Legionella Risk Assessment

A Legionella Risk Assessment is a legal requirement for anyone responsible for managing water systems in buildings. Its purpose is to identify conditions where Legionella bacteria may grow and spread, which can cause Legionnaires’ disease — a serious and potentially fatal lung infection.

What the Assessment Involves

• Inspecting water systems: Hot and cold water systems, tanks, showers, taps, and cooling towers are examined.
• Identifying risks: Conditions such as warm water temperatures (20°C–45°C), stagnant water, limescale, and biofilm are identified.
• Evaluating exposure: Consideration of who may be at risk and how bacteria could be transmitted.
• Implementing control measures: Recommendations may include flushing unused outlets, temperature control, cleaning tanks, and routine maintenance.
• Recording and reviewing: All findings are documented and reviewed regularly or whenever the water system changes.

A Legionella risk assessment must be carried out by a trained and competent professional . It is not just about legal compliance — it is about protecting people, preventing outbreaks, and ensuring safe water management.

Why a Legionella Risk Assessment Is Important

• Meets legal obligations under health and safety legislation
• Protects occupants, staff, and visitors from Legionnaires’ disease
• Helps identify and control risks before they become serious problems
• Demonstrates duty of care by property owners and managers

Regular Legionella risk assessments help maintain safe water systems, ensure compliance, and reduce the risk of serious health incidents.