Legionella risk assessment.

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What is a legionella risk assessment?

A legionella risk assessment is a structured review of your water systems that identifies where Legionella bacteria could grow and spread, then sets out practical controls to prevent it. In the UK, dutyholders must assess and manage this risk in line with the HSE’s Approved Code of Practice L8 and the supporting HSG274 guidance. A competent assessment helps you meet legal obligations under the Health and Safety at Work etc. Act, the Management of Health and Safety at Work Regulations, and COSHH.

Our specialists complete BS 8580-1:2019 compliant risk assessments for hot and cold water, cooling towers, and other risk systems. Findings are evidenced with clear documentation, and any sampling is processed through UKAS-accredited laboratories for reliable results. As an LCA-accredited provider, we deliver independent, system-specific advice you can act on with confidence.

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Why choose Complii?

How we can help.

What is a legionella risk assessment?

Proven compliance

Your assessment is aligned with ACoP L8, HSG274 and BS 8580-1, giving you defensible evidence of due diligence for insurers, auditors and regulators.

Reduced health risk

By pinpointing hazardous conditions such as stagnation, sub-optimal temperatures, poor materials or ineffective controls, you lower the chance of Legionnaires’ disease.

Actionable priorities

You receive a clear, prioritised action plan that separates urgent issues from recommended improvements, so you can allocate time and budget effectively.

Assured data quality

Where sampling is appropriate, analysis is carried out by UKAS-accredited laboratories. Results are interpreted by competent assessors for precise decision making.

Better management control

We review records, schematics and responsibilities, then advise on practical monitoring regimes, logbooks and written schemes of control that work day to day.

Scalable support

From single sites to complex portfolios, your reports follow a consistent format, making it easier to benchmark risk, track progress and verify closure of actions.

You questions answered.

Yes. Dutyholders must identify and control the risk from legionella in work activities. A suitable and sufficient assessment is the foundation for compliance with ACoP L8 and related legislation.
Review at least every two years, and sooner if there are system changes, building use changes, control failures, new information about risk, or a suspected or confirmed case of legionellosis.
A site survey, validation of schematics, temperature checks, review of management controls and records, identification of risk factors, and a written report with prioritised recommendations. Sampling is included where justified by risk.
A competent, independent assessor with the right technical knowledge and sector experience. LCA accreditation and BS 8580-1 competence criteria provide a robust benchmark.
Landlords must assess the risk in their properties and implement proportionate controls. The level of detail depends on the system and occupancy. Many choose a professional to ensure completeness.
You implement the written scheme of control and close actions to the agreed timescales. We can provide training for dutyholders and responsible persons, routine monitoring, and periodic review.

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