What should a Legionella risk assessment schedule include?

A suitable Legionella risk assessment schedule should translate the findings of the assessment into a controlled programme of reviews, inspections, monitoring, testing and follow-up. It should show what is to be done, why it is required, who is accountable, what evidence must be retained and how the programme changes when the level of risk changes.

Scope of the assessment

The schedule should identify the premises, water systems and areas covered. This may include hot and cold water services, storage tanks, calorifiers, showers, thermostatic mixing valves, spa or pool systems, cooling systems and other aerosol-generating equipment where present. Shared, rarely used or difficult-to-access outlets should be identified rather than treated as part of an undefined general system.

It is also useful to record any exclusions and explain them. For example, a system may be outside the assessment because it has been permanently isolated, removed or assessed under a separate control arrangement. Clear boundaries prevent gaps in responsibility between a building owner, occupier, facilities provider and specialist contractor.

Risk-based review logic

The schedule should explain the basis on which review dates and activities have been selected. Relevant factors can include the complexity and condition of the water system, temperature control, water storage, stagnation, aerosol generation, occupancy, vulnerable individuals and the quality of existing control measures. A fixed calendar date without this reasoning gives little indication of whether the programme remains appropriate.

Intervals should therefore be justified by the assessment and applicable guidance rather than copied from a generic template. The schedule can state the normal review interval, the circumstances that shorten it and the person authorised to approve a change. Where a higher-risk system needs more frequent oversight, that should be visible in the schedule instead of being buried in supporting documents.

Planned activities and control parameters

Each scheduled activity should describe the control being checked and the evidence expected. Depending on the system, this may include:

• temperature checks at relevant parts of hot and cold water systems;
• inspection of tanks, calorifiers, pipework, outlets and fittings;
• checks for dead legs, low-use outlets, leaks, corrosion, scale, contamination or poor insulation;
• flushing or other arrangements for outlets that are not regularly used;
• verification of cleaning, disinfection and maintenance work;
• monitoring of water treatment or chemical control measures where they form part of the system; and
• microbiological sampling where the risk assessment or investigation indicates that testing is appropriate.

Measured results should be assessed against the relevant control standard or operating limit. A schedule is more useful when it specifies what constitutes an acceptable result, what happens when a result is outside the expected range and who must be informed.

Responsibilities and competence

The document should distinguish between the person with overall responsibility for water safety and those carrying out individual tasks. It should name, or otherwise clearly identify, the responsible person, deputies, operational staff, maintenance providers, assessors and laboratories involved in the programme. Contact details may be held in a controlled register rather than repeated on every page.

Responsibilities should cover arranging access, completing checks, reviewing results, authorising remedial work, closing actions and escalating unresolved issues. The schedule should also indicate the competence required for each task. Routine observations by trained staff are different from a formal risk assessment, specialist sampling, interpretation of laboratory results or design of remedial works.

Action management

Every adverse finding should lead to a recorded action with a clear owner, target date, priority and completion status. The schedule should allow the organisation to distinguish between an observation, a corrective action and an urgent control failure. It should also record how completion is verified, such as a follow-up inspection, repeat measurement, laboratory result, maintenance record or revised assessment.

Open actions should be reviewed at an appropriate management level. If a control cannot be restored promptly, the record should explain the interim measures, any restrictions placed on the affected outlet or system and the basis for deciding when normal operation can resume.

Records and document control

The schedule should identify the records that support each activity, including completed check sheets, temperature logs, sampling results, cleaning certificates, maintenance reports, photographs, training records and correspondence about significant decisions. Records should be legible, dated and traceable to the relevant building, system, asset or outlet.

Version control is important where several people use the schedule. Include the document owner, issue date, revision history, approval status and the date of the next planned review. When a risk assessment, schematic, asset register or control procedure changes, the schedule should be checked for related amendments so that the documents do not contradict one another.

Links to wider water safety arrangements

A Legionella risk assessment schedule should sit within the organisation’s wider water safety management system. It should cross-reference the current risk assessment, written control scheme, system schematics, asset information, emergency arrangements and relevant maintenance procedures. It should also reflect the principles in applicable UK guidance, including the Health and Safety Executive’s guidance on the control of legionella bacteria in water systems.

Before approval, the schedule should be checked against the actual installation and the organisation’s resources. A concise, site-specific programme with clear evidence requirements is preferable to a long generic list that cannot be followed or audited.