Who is responsible for arranging a commercial legionella risk assessment?

Responsibility for arranging the assessment should be assigned through the organisation’s health and safety management structure, with a named person given sufficient authority, resources and access to make suitable arrangements. In a larger organisation, this may involve a property, estates, facilities or health and safety team rather than one individual acting alone.

The responsible organisation should first establish who controls each relevant part of the premises and water system. This is important where ownership, occupation, maintenance and facilities management are divided between different parties. A written agreement may allocate particular tasks to a landlord, tenant, managing agent, facilities contractor or specialist water hygiene provider, but contractual wording does not remove the need for clear oversight or cooperation.

Where more than one organisation has duties at the same premises, they should share relevant information and coordinate their arrangements. For example, a landlord may control the fixed water installation, while a tenant controls the way the building is occupied and operated. Both parties may need to contribute information to the assessment, including details of occupancy, outlets, vulnerable individuals, planned shutdowns and any changes to the system.

The person commissioning the work should check that the assessor is competent for the type and complexity of the premises. Competence involves more than holding a job title. The assessor should have appropriate knowledge of legionella risks, water systems, inspection methods, control measures and the relevant guidance. They should also be able to identify limitations in the information available and explain where further investigation is necessary.

Arranging an assessment involves more than requesting a report. The commissioning party should provide accurate background information, arrange access to plant rooms and outlets, identify areas that cannot be inspected, and explain any known incidents, system alterations or control problems. The brief should cover all relevant water systems, including those that may be overlooked during a routine inspection, such as little-used outlets, storage tanks, showers, decorative features or localised systems.

Once the assessment is complete, the duty holder or controlling organisation remains responsible for considering the findings. The report should be reviewed by someone who understands the premises and has authority to approve corrective action. Recommendations may include changes to monitoring, temperature control, flushing, cleaning, maintenance, isolation or system design. Each action should have an owner and a proportionate target date, with evidence retained when it has been completed.

A risk assessment is not a substitute for day-to-day control. The responsible organisation must ensure that the written scheme, monitoring records, maintenance arrangements and escalation process reflect the risks identified. Staff and contractors may need suitable instruction so that they understand their roles, know how to record results and recognise readings or conditions that require further action.

The assessment should also be revisited when circumstances change. Relevant triggers can include refurbishment, changes in water use, alterations to occupancy, extended periods of vacancy, installation or removal of equipment, changes to maintenance contractors, or evidence that existing control measures are ineffective. A review may show that a new assessment or additional technical investigation is needed.

Blue Fish Water Management Ltd can support businesses by carrying out legionella risk assessments, reviewing water safety arrangements and advising on practical remedial measures. Its wider services include UKAS-accredited water testing, compliance audits, system monitoring, training and remedial works, allowing identified issues to be considered alongside the organisation’s wider water management arrangements.