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Legionella.io

Free tool · Risk rating

Legionella risk-rating calculator

Answer a few questions for an indicative risk rating for your building. It helps you prioritise; it is not a competent risk assessment.

1. Who uses the building?
2. Which water systems are present? (tick all that apply)
3. Water temperatures?
4. Any dead legs or little-used outlets where water can sit?
5. Is there a current risk assessment and monitoring in place?
How to read the rating

This is an indicative score to help you prioritise, not a verdict. Lower means basic controls are usually enough; medium means an assessment and routine monitoring are expected; higher means a competent, site-specific assessment and active control should come first. Only a competent risk assessment can decide your real controls.

Indicative prioritisation aid based on HSE duties, not a risk assessment or legal advice. Source:HSE — what you must do.