Legionella Risk Assessment Template

This template is designed to help a responsible person carry out a Legionella Risk Assessment for all short-term let premises.

• Legionella is classified as a ‘hazardous substance’ and you are required to undertake a risk assessment, and any subsequent remedial actions, in order to protect both your staff and customers.
• If you have five or more employees, you need to record both what assessment and actions you undertook. While it is not a legal requirement to record the assessment and actions if you have fewer than five employees, it is always recommended that you do so in case you are challenged at a later date.

Legionnaires’ disease is a potentially fatal form of pneumonia caused by Legionella bacteria. While these bacteria are common in natural water systems, they usually occur in numbers too small to cause health problems. However, in the right conditions these bacteria can multiply quickly and cause a significant health risk.

These conditions are where water is maintained between 20–45C, is stored or recirculated, where there is a source of nutrients in the water (including rust or scale) and where there are aerial water droplets. This means that water tanks, spas or hot tubs, air conditioning units and showers are the most common places for the bacteria to breed.

If you have self-catering property or a B&B with a normal residential water system, this risk assessment will be straight forward as the risk of Legionnaires’ Disease should not be high. A full specialist assessment is generally only needed if you have a large commercial property or you are uncertain of the property’s water system.

If you have machinery that contains water, such as air conditioning units or a spa/hot tub, then special attention needs to be made to ensure that this is regularly serviced and cleaned.

If you operate a property where the water system is not in regular use (e.g. a self-catering property that has long void periods or closes over winter) then additional precautions need to be undertaken to make sure that the water in the system does not stagnate. If your property is going to be vacant for a significant period, you should either drain or flush the system before the guests arrive.

• Further information on Legionella and how to control it in water systems is available on theHealth and Safety Executive website.
• For hot tubs and spa pools, download ‘Control of legionella and other infectious agents in spa-pool systems’.

Who can carry out an assessment?

You can carry out a Legionnaire’s risk assessment yourself if the property is a single dwelling with its own water supply (hot and cold) and you are competent to do so. You should:

• understand different types of water systems
• understand Legionella bacteria and the factors which increase the risk of an outbreak in a domestic setting
• understand the control measures which if present will reduce the risk of an outbreak within a domestic setting

If you do not consider that you are competent then you should seek advice.

The risk assessment process

The practical risk assessment should include a site survey of the water system. A template is attached which is suitable for a basic system and can be adapted as required.

The assessor should understand the water systems and any associated equipment in the property, in order to conclude whether the system is likely to create a risk from exposure to Legionella.

It is important to identify whether:

• water is stored or re-circulated as part of the system (areas of risk include water tanks, dead legs, shower heads and/or long runs of pipe work containing warm water)
• the water temperature in some or all parts of the system is between 20 – 45°C (hot water should be stored in any tanks at 60°C)
• there are sources of nutrients such as rust, sludge, scale and organic matters
• conditions are present to encourage bacteria to multiply
• it is possible for water droplets to be produced and, if so, whether they could be dispersed, e.g. showers
• there are parts of the system that are used infrequently e.g. guest bathrooms
• it is likely that any of the guests are more susceptible to infection due to age, health or lifestyle and whether they could be exposed to any contaminated water droplets

Reviewing the risk assessment

If the risk assessment concludes there is no reasonably foreseeable risk or the risks are insignificant and are managed properly to comply with the law, the assessment is complete. Although no further action may be required at this stage, existing controls must be maintained. The assessment of risk is an ongoing process and not merely a paper exercise. The assessment should be reviewed regularly and specifically when there is reason to suspect it is no longer valid.

Click here for the Legionella Risk Assessment Template document

Author of guidance: ASSC

Date of guidance: January 2024

Version Number: V1

 Disclaimer – Guidance Sheets are written by experienced Members of the ASSC and other experts. The information in the ‘Guidance Sheet’ is provided by the ASSC for use by Members in support of their own independent business decisions. It does not constitute advice or instruction for which the ASSC can be held liable in any way whatsoever. All Members and other readers remain responsible for the consequences of any decisions taken whether in the light of information gained from this Guidance Sheet or not.