What does a sector-specific Legionella Risk Assessment include?

A sector-specific Legionella Risk Assessment is a structured record of how Legionella risk is identified, evaluated and managed within a particular type of organisation. It combines a site inspection with a review of the water system, management arrangements and relevant operational activities, then sets out evidence-based actions that are appropriate to the sector and the site.

Scope and site context

The assessment should define the premises and systems covered, including any exclusions or limitations. It normally records the nature of the organisation, how the building is occupied, how water is used and whether different areas operate under separate management arrangements. This context matters because a care setting, hotel, school, factory and office may have different patterns of occupancy, water demand and exposure.

The assessor should also identify areas that may require separate consideration, such as accommodation, clinical or treatment rooms, showers, staff facilities, plant rooms, vacant parts of a building, rarely used outlets and external or process-related water systems.

Information gathered before and during the assessment

A robust assessment is based on more than a visual check. Relevant information may include:

• available water system drawings, schematics and asset registers;
• records of maintenance, cleaning, disinfection and temperature checks;
• previous sampling results, inspection reports and incident records;
• details of contractors, responsible persons and escalation arrangements;
• records of changes to the building, water services or patterns of use; and
• information about areas that are closed, underused or subject to unusual demand.

Where records are incomplete, that absence is itself relevant. The report should distinguish between information confirmed from documentation, information observed during the visit and information that still needs to be verified.

Assessment of the water system and its condition

The report should explain how water enters, is stored, heated, distributed and discharged through the premises. It should consider the condition and arrangement of relevant equipment, including storage vessels, calorifiers, hot and cold water distribution, secondary return systems, outlets, showers, strainers, expansion arrangements and any specialist systems that can create aerosol or stagnation risks.

Potential contributing factors should be recorded clearly. These can include low or fluctuating temperatures, insufficient circulation, dead legs, infrequently used outlets, poor insulation, scale, corrosion, sludge, inadequate access for maintenance or changes that have left the system different from its original design. The significance of each observation should be explained rather than simply listed.

Sector-specific considerations

The assessment should show how the sector changes the risk profile and the controls required. For example, it may consider:

• the presence of residents, patients, pupils, guests, tenants, employees or members of the public;
• whether individuals may be more susceptible to Legionnaires’ disease;
• the duration and frequency of occupancy;
• personal care, bathing, therapeutic or recreational water use;
• seasonal occupancy, room turnover or periods of closure;
• production processes, welfare facilities and restricted-access areas; and
• how the organisation manages multiple buildings, departments or responsible parties.

This analysis should be specific enough to explain why a control is required and who is affected if it is not maintained. Generic wording copied from another type of premises does not demonstrate that the assessment reflects the actual operation of the site.

Management and procedural review

A sector-specific assessment should examine whether the organisation has a workable water safety management structure. This includes checking that duties are allocated to suitably competent people, that contractors are managed, that staff understand relevant procedures and that information passes between facilities, estates, operational and senior management teams where necessary.

It should also review arrangements for routine checks, dealing with abnormal results, managing temporary changes, bringing systems back into use after closure and recording completed actions. For larger or multi-occupancy premises, the report may need to clarify how responsibilities are divided between the building owner, landlord, managing agent, employer, tenant and specialist contractor.

Risk rating and prioritised recommendations

The findings should be assessed consistently, with the report explaining the factors that affect the level of concern. Recommendations should be practical and prioritised according to the nature of the deficiency, the people potentially exposed and the importance of the affected system.

Actions may involve correcting system defects, removing unnecessary sections of pipework, improving access, updating procedures, reviewing outlet use, strengthening record keeping or arranging further investigation. Each recommendation should identify the relevant location or asset and, where appropriate, indicate the type of person or organisation responsible for taking it forward. It should not recommend routine testing as a substitute for correcting a known underlying problem.

Supporting evidence and report quality

A useful report normally includes the assessment date, assessor details and competence information, premises covered, documents reviewed, inspection limitations and a clear description of the method used. Photographs, marked-up plans, asset references or other supporting records can help the dutyholder connect each finding with the correct part of the system.

The report should be understandable to both technical and non-technical readers. It should separate observations, risk judgements and recommended actions, avoid unexplained abbreviations and make clear where further information is needed. It should also identify circumstances that would require the assessment to be revisited, such as alterations to the water system, changes in occupancy, a significant incident, persistent control failures or a change in how the premises is used.

A Legionella Risk Assessment is not simply a water test result or a statement that a system has passed inspection. Testing can support an investigation or ongoing control programme, but the assessment must connect the physical system, the way the premises operates and the organisation’s management arrangements. That connection is what makes the document useful for ongoing compliance and informed decision-making.