Preventing legionnaires' disease

Preventing legionnaires' disease

Mandatory notification of cooling towers and warm-water systems

To control legionnaires' disease we maintain a register of water-cooling systems in premises (including cooling towers and warm-water systems) across our local area, in line with the Public Health Act 2010.

It is a legal requirement for all owners and/or occupiers of buildings who install and operate a cooling tower or warm-water system (regulated system) to notify the City, using the approved notification form, and pay the $115 fee. Warm water systems other than in hospitals, which includes nursing homes, declared mental health facilities and private facilities, are exempt from notifying the City.

Please note: No fee is payable if changes are made in the particulars section (part 5) of the form.

This also includes any changes to the system when any of the following occurs:

  • a new system is installed on a premises
  • there is a change of owner or occupier for a building on which a system is located
  • the system is modified (for example, cooling towers added or removed)
  • the contact details for the building manager changes
  • the system is decommissioned.

Completed notification forms should be emailed to

Regulatory changes to the management of water-cooling systems

The requirements to install, operate and maintain cooling water systems in NSW are found in:

  • Public Health Act 2010
  • Public Health Regulation 2012 (as amended)
  • Australian Standard AS/NSZ 3666 – 2011 Air-handling and water systems of buildings – Microbial control.

The regulation was amended on 10 August 2018 to provide a performance-based, risk management approach to prevent Legionella bacteria in water cooling systems.

From 10 August 2018, building owners and occupiers must ensure the following requirements are complied with:

  1. A competent person (defined in Public Health Regulation 2012) must undertake a risk assessment of the cooling water system and document it in a risk management plan, at least every 5 years (more frequently if required, or for higher risk systems).
  2. A competent person prepares a certificate confirming the risk management plan has been completed, which must be submitted to the City within 7 days of completing the risk assessment.
  3. Compliance with the risk management plan and Public Health Regulation 2012 must be independently audited and documented in an audit certificate, which is to be submitted to the City every year.
  4. Monthly sampling and testing of the system for Legionella and heterotrophic colony count must be undertaken.
  5. High test results for Legionella (≥1000 cfu/mL) and heterotrophic colony count (≥5,000,000 cfu/mL) must be reported to the City within 24 hours of receiving the results.
  6. Unique identification numbers for cooling towers must be displayed on all cooling towers. Please note, while the City allocates the unique identification numbers, we do not specify which tower these are to be placed on. This is for the competent person to decide and advise on behalf of the owner/occupier and document it in the risk management plan.

To report a high test result for Legionella and/or heterotrophic colony count, you must contact the City as soon as possible:

02 9265 9333

You also need to complete the standard notification of reportable test results form from the NSW Health website and email it to


If the City identifies non-compliance of the requirements for regulated systems under the Public Health Act 2010, authorised City officers can order building occupiers/owners to comply with the requirements. Additionally, officers can conduct inspections of premises on which regulated systems are located and charge fees.

Failure to comply with the requirements under the act can result in legal notices, orders, penalty infringements (fines), and/or legal proceedings against a building occupier or owner.

For further information on the NSW Health requirements or to access standard forms, templates and fact sheets, please visit NSW Health: Legionella control.

What is legionnaires’ disease?

Legionnaires' disease is a potentially fatal type of pneumonia caused by Legionella bacteria that may also cause a flu-like condition called Pontiac fever. Legionnaires’ disease occurs when someone inhales the Legionella organism and it penetrates deep into their lungs, possibly through a contaminated aerosol from a cooling tower.

The disease has the potential to affect everyone, but vulnerable groups are more at risk. This includes older people with existing health problems such as respiratory disease, people with autoimmune diseases, people taking immune-suppressant drugs and people who are heavy smokers.

Legionella can be controlled by proper water treatment procedures, regular cleaning and maintenance, and applying risk management.


We hold free workshops for anyone who operates a water-cooling system in the local area. This is a simple way to get cooling tower safety messages across to owners, occupiers and building managers.

The course is an excellent resource on controlling Legionella in cooling towers and how to maintain cooling tower systems. It also covers complying with the regulation requirements and preventing the spread of Legionella.

Making sure that owner/occupiers and building managers have the right skills and knowledge will help you to meet your legal obligations.

Upcoming event dates will appear on this site, or you can contact the City at the phone number or email below.


Standards and Policy, Health and Building02 9265 9333NSW Public Health: Legionella control

The website link above provides NSW Public Health guidelines, fact sheets and publications on Legionella control. It also provides all information on the new requirements.

Last updated: Wednesday, 1 July 2020