If you manage facilities that have hot and cold water systems, then you need to undertake regular legionella risk assessments reviews. Under most circumstances, these should be carried out at intervals considered appropriate for the characteristics of your water systems.

That said, there are a number of situations that require you to undertake more frequent reviews, and failing to do so can land you in breach of the law. To help you understand this requirement, we’ll talk you through the most common situations.

1. When you make changes to your water systems

If you make any changes to your water system, whether it’s adding or removing pipework or other components, you must ensure your legionella risk assessement reflects these changes.

2. If users fall within a high-risk category

This is normally the case if your facility is used for health or social care, such as a home for the elderly or a hospital that cares for people with an impaired immune system. Vulnerable people like these are more susceptible to infection from legionella and developing Legionnaire’s disease.

3. When your water system has a change of use

This essentially covers when your premises undergo a change of use. For example, if a warden’s residential annexe in your care home were to be converted to become part of the care home itself, you would need to undertake a new risk assessment for the whole property.

4. When monitoring and management are not effective

If you find that your legionella monitoring and management processes are insufficient or ineffective in keeping the bacteria under control, then you need to undertake a new risk assessment as a starting point for making these processes fit for purpose.

5. If the HSE issues new guidance

Occasionally the HSE will issue new guidance regarding the control and prevention of legionella. If this happens, you may need to review your risk assessment to ensure that it complies with the new rules.

6. If your water testing reveals positive legionella

If regular water testing reveals the presence of legionella in your water systems – or even if there are new grounds to suspect that legionella is present – you must review your legionella risk assessment without delay to highlight areas of concern and where remedial action may be required.

To summarise, there is no hard and fast rule to say how often you should undertake a legionella risk assessment review. At the very minimum you need to complete one at least every two years, but in many cases it is wiser – and may be a legal duty – to undertake them more frequently. Given than legionella is a major risk to life, and an outbreak can ruin your business’ reputation and result in prosecution if rules have not been adhered to, it’s wise to err on the side of caution.

If you’d like to learn more about managing legionella, as well as the key factors you should consider when implementing a legionella risk assessment and control regime, download our new free guide: The facilities’ manager’s guide to legionella risk assessments.