Legionnaires’ disease is a potentially fatal form of pneumonia caused by the inhalation of small droplets of contaminated water containing Legionella.

All man-made hot and cold water systems are likely to provide an environment where Legionella can grow. Where conditions are favourable (ie suitable growth temperature range; water droplets (aerosols) produced and dispersed; water stored and/or recirculated; some ‘food’ for the organism to grow such as rust, sludge, scale, biofilm etc) then the bacteria may multiply thus increasing the risk of exposure. It is a simple fact that the organism will colonise both large and small systems so both require risks to be managed effectively.

The Control of Substances Hazardous to Health Regulations 2002 (COSHH) provides a framework of actions to control the risk from a range of hazardous substances, including biological agents such as Legionella – to identify and assess the risk, and implement any necessary measures to control any risk.

Therefore a “suitable and sufficient” Risk Assessment should be undertaken to identify the hazards, assess the risk and to define suitable control measures to eliminate, reduce or control the risk.

In some small modern practices such as those with combination boilers similar to domestic premises and simple water systems it may be possible to do the risk assessment in-house. For older properties, for properties that have been combined or older properties that have been adapted, where older, more commercial boilers are used or where water system are complex it will be necessary to get external expert assistance.

The Health and Safety Executive have issued an Approved Code of Practice – Legionnaires’ disease. The control of legionella bacteria in water systems – L8 (Fourth edition) Published 2013 which will provide suitable guidance. HSE code of practice L8

This leaflet Legionnaire’s Disease – a guide for dutyholders, produced by the HSE (Health and Safety Executive) is informative and will enable most practices to feel confident that they know enough to make a reasonable judgement and risk assessment.

Back to Top


Risk Assessment: Hot and Cold Water Supply/Legionnaires’ Disease

Water systems can harbour legionella bacteria which is the cause of Legionnaires’ disease (which is a potentially fatal pneumonia) and other related diseases.

Infection is caused by breathing in small droplets of water contaminated by the bacteria. Everyone is potentially susceptible to infection but some people are at higher risk, e.g. those over 45 years of age, smokers and heavy drinkers, those suffering from chronic respiratory or kidney disease, and people whose immune system is impaired.

Legionella bacteria can contaminate and grow in hot and cold water systems. They survive low temperatures and thrive at temperatures between 20°C-45°C if the conditions are right, e.g. if a supply of nutrients is present such as rust, sludge, scale, algae and other bacteria.
They are killed by high temperatures.

It is important to balance the risk between likelihood of legionella bacteria building up in the water system, and the risk of scalding vulnerable people, such as the elderly, children or disabled people. Should the water be coming out of the hot water taps at too high a temperature, the risk of scalding is very high.

Risks exist in cases where water droplets could be inhaled, e.g. in a shower.

Preventing and controlling the risk:

  • Maintaining the hot water system at or above 60°C (at which the bacteria cannot survive) but beware of the risk of scalding.
  • Flush infrequently used pipes through regularly (e.g. turn showers on weekly)
  • Ensure water storage tanks are covered and are inspected/ flushed/ descaled/ disinfected periodically.
  • Ensure that monthly checks are carried out on taps to ensure that the cold water temperature is below 20°C after running for up to two minutes the hot water temperature is at least 50°C within a minute of running the water.
  • Note also that the HSE encourages the restriction of hot water outlets to 44°C maximum in non-domestic premises where “vulnerable” people may have access, (to reduce the risk of scalding) this would include the washing facilities available to the public at the Medical Centre.

Back to Top


CQC Essential Standards of Quality and Safety

Regulation 15 – Premises and Equipment

The Health and Social Care Act 2008 (Regulated Activities) Regulations 2014: which says:



All premises and equipment used by the service provider must be—

  • clean,
  • secure,
  • suitable for the purpose for which they are being used,
  • properly used
  • properly maintained, and
  • appropriately located for the purpose for which they are being used.
  • The registered person must, in relation to such premises and equipment, maintain standards of hygiene appropriate for the purposes for which they are being used.

For the purposes of paragraph (1)(b), (c), (e) and (f), “equipment” does not include equipment at the service user’s accommodation if—

such accommodation is not provided as part of the service user’s care or treatment, and

such equipment is not supplied by the service provider.

‘Premises’ and ‘equipment’ are defined in the regulations. The definitions make sure that the term ‘premises’ does not apply to the person’s own accommodation where accommodation is not provided as part of their care and treatment. In addition, ‘equipment’ does not include equipment at the person’s own accommodation, where it is not provided as part of their care or treatment.

Related guidance for Regulation 15 includes the  Control of substances hazardous to health The Control of Substances Hazardous to Health Regulations 2002 in which Legionnaires Disease is referenced.

The following documents are also listed that relate to legionnaires disease:

  • All currently valid Health Technical Memoranda (HTMs) published by the Department of Health
  • All currently valid Health Building Notes (HBNs) published by the Department of Health
  •  Legionnaires’ disease The control of legionella bacteria in water systems – Approved Code of Practice and guidance on regulations – L8 (Fourth edition) Published 2013

The key one is the HSE L8 4th Edition (2013) code of practice.

As employers, practices do have to carry out a risk assessment for legionnaires disease. The HSE code of practice states “A simple risk assessment may show that the risks are low and in such case no further action will be necessary. Examples include small, domestic-type water systems where temperatures and turnover are high, or where instantaneous water heaters are used.” Guidance from the HSE makes it clearer: “If you decide that the risks are insignificant, your assessment is complete. You need take no further action other than to review the assessment periodically in case anything changes in your system.” It has been suggested that there is no legal requirement for a third party specialist to carry out an assessment, but that the assessment should be carried out by a suitably qualified/competent person – this isn’t quite what the code of practice says, it’s that the “duty holder” (i.e. the employer) has to have access to competent help and advice.

CQC is not asking for anything new or different from what practices should already be doing as employers. It is for the practice to assess its risk and take appropriate action.

Back to Top


Legionnaires Disease and Water Safety in Primary Care Routine

Information from Matthew Richardson, Specialist Nurse – Infection Prevention and Control.

Primary Care practices have a duty to ensure that their water systems do not pose a risk to the health and safety of employees and visitors from legionella bacteria.

All water systems in Primary Care practices require a risk assessment. However, not all systems will require elaborate control measures and responses and actions should be proportionate to the identified risk. A simple risk assessment may show that the risks are low and being properly managed to comply with the law. It is likely to that most practices will not require anything more than a basic local risk assessment and simple in-house control measures.

This document is a summary designed to introduce Primary Care practices to the requirements around water safety and help practices to determine whether external consultation is proportionate and necessary.

With thanks to West Hampshire ICB for this information.

Back to Top


ClosePlease loginn

Last Reviewed Date