Key messages

  • A 'water delivery system' includes, amongst other things, warm water systems, thermostatic mixing valve systems (TMV) and tepid loop systems.
  • Regulation 62 of the Regulations requires that the responsible person must take reasonable steps to manage the risks of Legionella in water delivery systems in certain premises.
  • Legionella has been detected in water delivery systems (including in systems with TMVs and Tepid loop systems) associated with showers and ice machines in hospitals and aged care facilities in Victoria.
  • Car wash facilities have also been linked to cases of legionellosis.
  • The department strongly recommends that a Legionella risk management plan be developed for your water delivery system.

Water delivery systems ­– legislation

The Public Health and Wellbeing Regulations 2009 require certain premises with water delivery systems to manage the risks associated with Legionella.

Regulation 62 of the Regulations requires that the responsible person must take reasonable steps to manage the risks of Legionella in water delivery systems in certain premises.

The 'certain premises' that the regulations apply to are:

  • aged care
  • health services
  • health service establishments
  • registered funded agencies
  • correctional services
  • commercial vehicle washes.

The responsible person is any person who owns, manages, or controls the water delivery system.

More information about the legislation is available by downloading the Water Delivery System fact sheet.

The Act and regulations are available at the Victorian legislation and parliamentary documents website.

Water delivery systems ­– Legionella risks

Legionella has been detected in water delivery systems associated with showers and ice machines in hospitals and aged care facilities in Victoria. In addition, in 2008, a car wash facility was linked to seven cases of Legionnaires’ disease.

Legionella is an organism that is ever-present in the environment and found in very low concentrations in the potable water supply. In the right environment, however, the Legionella bacteria are able to multiply and pose significant risks to the health of individuals exposed to the bacteria.

The risk of Legionella growth increases in water delivery systems that store water at temperatures between 20 °C and 60 °C. In addition, the risks of Legionella growth in commercial car washes are increased when rubber hosing is used and when there is an absence of a biocide.

People may contract Legionnaires’ disease if they are exposed to small droplets containing the bacteria, like those produced by high pressure hoses or showers.

Water delivery systems ­– requirements under the Regulations

Whilst the regulations no longer require testing warm water systems periodically for Legionella, it is recommended that all high-risk facilities undertake a water sampling program as part of a risk management approach. The Enhealth Guidelines for Legionella Control in Health and Aged Care Facilities provide assistance for developing a sampling strategy.

It is very important that you develop a disinfection procedure before you start sampling.

It is a requirement of the regulations that within 24 hours of receiving a report that Legionella has been detected in a water sample taken from a water delivery system that the responsible person must ensure that the water delivery system is disinfected. Satisfactory disinfection procedures are detailed in the Enhealth Guidelines for Legionella Control in Health and Aged Care Facilities.

Following the detection of legionella in a water delivery system (TMV and Tepid Loop systems):

  • Stop using all the showers in the system.  That means stop using all the showers connected to the tepid loop or hot loop (for TMV systems) where legionella was detected until the system has been disinfected.
  • Inform the relevant people to ensure that there is a heightened surveillance for case of Legionnaires Disease.
  • Take a re-sample from the system 2-7 days after the disinfection.

The department recommends using a chemical disinfection over a heat disinfection. However, if a heat disinfection is used it is very important to manage the risk of scolding.

Water delivery systems ­– managing the risks of Legionella

In order to comply with the Regulations and reduce the risk of Legionella in your warm water system, the department recommends that a Legionella risk management plan be developed for your water delivery system in line with Enhealth Guidelines for Legionella Control in Health and Aged Care Facilities. A risk management template has also been developed to assist with the process.

These Guidelines are designed to be used throughout Australia and New Zealand and do not incorporate the Victorian legislative requirements. A fact sheet that describes the requirements under Victorian law relating to water delivery systems should be downloaded and consulted.

Assessments of water delivery systems should not be restricted to showers systems and should include any system where the water in the system is at temperatures between 20°C and 60°C combined with the potential for a person to be exposed to respirable sized water droplets from the system.

Commercial car washes – suggestions to manage the risks associated with Legionella

To manage the risks associated with Legionella in commercial car washes, the department recommends that the following be considered:

  • not storing water at temperatures between 20 °C and 60 °C
  • replacing warm water storage with instantaneous units
  • replacing rubber hosing with poly tubing, metal tubing, or copper tubing
  • regularly disinfecting the system with a chlorine-based disinfectant.

You can also obtain further information from the Australian Car Wash Association.