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Legionella Risk Assessment Builder

Answer nine quick questions about your building and its water system. You will get an indicative risk rating, whether self-assessment is reasonable or you need a competent assessor, and a monitoring schedule built for your system. Free and instant.

This tool structures your thinking around the same framework a legionella risk assessment uses: the Approved Code of Practice L8 and the technical guidance in HSG274. It is a starting point to help you build and record a proper assessment. It is not a risk assessment in itself, and it does not confirm that your system is safe or compliant.

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How the tool works

The Builder applies the control logic in HSG274 to the features you describe. Stored hot water and cold water tanks add inspection tasks; showers and spray taps add cleaning; little-used outlets add flushing; TMVs add servicing. Cooling towers and spa pools are treated as high risk in their own right, because both aerosolise water held in the growth range and both carry duties beyond a standard hot and cold water system. Vulnerable occupants raise the priority throughout, because the same exposure that causes mild illness in a healthy adult can be serious for someone who is elderly or unwell.

The result links each recommended check to the guide that explains how to do it and what to record. Work through them, write down what you find, and keep the record. Our free template gives you the structure, and the written scheme of control and log book guides show how the schedule becomes your ongoing record.

Important

This tool is general guidance, not advice on your specific premises. Legionella risk depends on the detail of the water system, how it is used, and who is exposed. For anything beyond a simple, low-risk system, and always where there is a cooling tower, a spa pool, or vulnerable people, use a competent assessor, usually one working for a Legionella Control Association registered company. This site does not provide medical advice.

Important This page is general guidance only. Legionella risk varies with the specific water system, its use, and the people exposed to it. You should consult a competent legionella risk assessor for advice on your premises. LegionellaCheck is an independent information service and is not affiliated with HSE, UKAS, the Legionella Control Association, or any water hygiene company. This site does not provide medical advice. If you suspect Legionnaires' disease, contact NHS 111 or your GP.