​The duly qualified person (DQP) manages cooling water systems on a routine basis, on behalf of the occupier.
The occupier can engage a DQP to perform part of their role under the amended Regulation.

Last updated: 01 February 2023

Who is the duly qualified person?

The Public Health Act 2010 (the Act) defines the DQP as a person who installs, operates or maintains a cooling water system.

DQPs are typically employed by a water treatment company, mechanical services company or other organisation involved in the management of cooling water systems.

What is the role of the duly qualified person?

The Act and Public Health Regulation 2022 (the Regulation) require certain actions to be performed by a DQP. These include:

  • installing, operating and maintaining the system.
  • performing monthly inspection, chemical analysis and microbial testing, and preparing a monthly report.
  • performing system cleaning at a frequency specified in the Risk Management Plan (RMP) (Approved Form 1).
  • implementing control strategies set out RMP.

The occupier may choose to contract a DQP to fulfil other responsibilities on their behalf, including:

  • notifying a new installation to the local government authority.
  • arranging for unique identification numbers to be displayed on each cooling tower.
  • receiving microbial test results from the laboratory and notifying reportable test results to the local government authority.
  • providing certificates of RMP completion and audit completion to the local government authority.
  • ensuring that required documents are readily available.

Occupiers may employ more than one DQP to manage different aspects of a system.

Can the occupier be a duly qualified person?

Yes. The occupier may carry out the role of the DQP if they meet the definition in the Act.

What licencing requirements does the duly qualified person need to fulfil?

Persons involved in the installation, operation and maintenance of cooling water systems should ensure they comply with the requirements set out by NSW Fair Trading.

A licence from NSW Fair Trading may be required before any air-conditioning or refrigeration work can be undertaken in NSW, regardless of the cost of the work and regardless of whether the work is residential, commercial or industrial.

Further information can be obtained from NSW Fair Trading.

How should maintenance activities be documented?

DQPs must complete the monthly report (Approved Form 3) each month to document:

  • site and contact details.
  • results of monthly inspection, maintenance (including servicing), chemical analysis and microbial testing.
  • any remedial actions taken or recommended.

DQPs must provide the monthly report to the occupier.

How should the duly qualified person carry out microbial sampling?

The DQP must sample the system every month to test for the presence of Legionella and other bacteria (heterotrophic colony count). Samples must be taken in accordance with AS/NZS 3666.3:2011 Air-handling and water systems of buildings - Microbial control - Performance-based maintenance of cooling water systems.

Samples must be tested by a laboratory accredited by the National Association of Testing Authorities.

How should the duly qualified person respond to reportable test results?

The DQP must urgently implement control strategies set out in the RMP and AS/NZS 3666 Part 3 if a test result shows:

  • Legionella count ≥10 cfu/mL
  • Heterotrophic colony count ≥100,000 cfu/mL.

The occupier must notify a test result to the local government authority as a reportable test result if it shows:

  • Legionella count ≥1,000 cfu/mL
  • Heterotrophic colony count ≥5,000,000 cfu/mL.

A reportable test result indicates that the management of the system needs to be urgently reviewed in order to prevent an outbreak of Legionnaires’ disease.

How should reportable test results be notified to the local government authority?

Reportable test results must be notified by the occupier to the local government authority, within 24 hours of receiving the result. The notification must be made in writing by completing the notification of reportable test results (Approved Form 4).

The occupier may engage another person, such as the DQP or laboratory, to make the notification to the local government authority on their behalf.

What documents and information must be readily available?

Required documents and information must be either kept in hard copy on the premises, or kept electronically and made available for inspection within 4 hours of request by an authorised officer.

Required documents include:

  • the current RMP
  • audit reports for the past 5 years
  • monthly reports (documenting inspection, maintenance (including servicing), chemical analysis and microbial testing) for the past 5 years
  • operating and maintenance manuals (including safety data sheets)
  • all records of the maintenance and service of the system.

Required information is the name and contact details of each DQP and competent person who provided services in the last 5 years.

What guidance and training is available?

The NSW Guidelines for Legionella Control in Cooling Water Systems explain the new requirements in detail, including the roles of the DQP.

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. DQPs 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