Legionella control in cooling water systems - Competent person

​The competent person plays a key role in carrying out a risk assessment of cooling water systems, and documenting it in a Risk Management Plan (RMP), on behalf of the occupier.

The occupier can engage a competent person to perform part of their role.

Last updated: 01 February 2023

​Who is the competent person?

The Public Health Regulation 2022 (the Regulation) defines the competent person as having appropriate training or practical experience (or both) in the installation, operation or maintenance of cooling water systems, sufficient to provide safe and satisfactory performance of these systems.

A person acting under the supervision of a competent person may prepare an RMP (Approved Form 1), provided that the competent person reviews and approves the RMP.

What is the role of the competent person?

The Regulation requires a competent person to undertake an effective risk assessment, in order to identify and document measures to limit the growth and transmission of Legionella bacteria.

The competent person should:

  1. assess the five risk categories and underlying risk factors for Legionella growth and transmission.
  2. assign an overall risk rating of low, medium, or high risk to the system.
  3. set requirements for system management based on the identified risks.

To do so, the competent person should:

  • inspect the system.
  • interview people who operate or maintain the system.
  • review monthly reports of inspection, maintenance (including servicing), chemical analysis and microbial testing, and operating and maintenance manuals.

Can the occupier be the competent person?

Yes. The occupier may carry out the role of the competent person if they meet the definition in the Regulation.

Can the duly qualified person be the competent person?

Yes. The duly qualified person who operates or maintains the cooling water system should have a sound understanding of the day-to-day management of the system. It is appropriate for this person (typically employed by a water treatment or mechanical services company) to carry out a risk assessment – if they meet the definition of competent person in the Regulation.

How should the risk assessment be documented?

The competent person must document the risk assessment in the RMP. This covers:

  • site and technical details of the system.
  • risk analysis and risk evaluation for the five risk categories.
  • maintenance plan, action plan, control strategies, and monitoring for the identified risks.

How should the risk assessment be notified to the local government authority?

The RMP includes a Certificate of RMP completion.

The occupier must provide the certificate to the local government authority within 7 days of completion of the risk assessment.

The occupier may engage another person, such as the competent person or duly qualified person, to make this notification on their behalf.

How often should risk assessments be carried out?

A competent person should carry out a risk assessment at least every 5 years.

More frequent risk assessments are required if:

  • the system was found to be high risk in the previous risk assessment. If so, risk assessments must be carried out every year until a low or medium risk level has been achieved.
  • the risk level of the system has changed, and the previous risk assessment is no longer valid. If so, a new risk assessment must be completed within 30 days of finding that the previous risk assessment was invalid.
  • an authorised officer directs the occupier to complete a new risk assessment.

A competent person must complete a risk assessment before a newly installed system commences operation.

What guidance and training is available?

The NSW Guidelines for Legionella Control in Cooling Water Systems explain the new requirements in detail, including the risk assessment process.

This series of factsheets summarises the key information for each stakeholder. The full set of factsheets can be found on Legionella control.

NSW Health has developed the Legionella Control in Cooling Water Systems training program together with TAFE NSW. Competent persons are encouraged to complete this training.

NSW Fair Trading licensing requirements

A licence from NSW Fair Trading may be required before any design, installation and maintenance of cooling water systems can be carried out. Further information can be obtained from NSW Fair Trading.

For more information

Current as at: Wednesday 1 February 2023
Contact page owner: Environmental Health