What is a cooling tower?
A cooling tower is a device that lowers the temperature of the water or other liquids by the process of evaporative cooling or an evaporative condenser that has an incorporated device containing either a refrigerant or heat exchanger.
Legionaries Disease can be associated with contaminated water including cooling tower water systems and spas, with most of Australia's outbreaks being linked to cooling towers.
Due to this link, water cooling towers need to be equipped with a disinfection process that aims to control the microbial growth of Legionnaire's disease. The disinfection processes must:
Be in operation at all times
Be certified by a qualified person annually as being an effective disinfection process
Be running in a effective manner to ensure that no test sample is taken from the tower that produces a test result with a Legionella count of more than 10 colony-forming units per millilitre, or a heterotrophic plate count of more than 100,000 colony-forming units per millilitre.
Along with the disinfection process, each tower needs to have an up to date manual. Each manual needs to include:
Physical details of the tower, equipment and systems
Information on maintenance and water treatment management
Cleaning, disinfection and emergency decontamination procedures
Operation and start up / shut down procedures
Details and dates of cleaning, services and microbial test conducted on the tower, and
Date, item of plant, equipment or system and nature of service performed including details on defects found or procedures undertaken
Under the Public Health Act 2010 and the Public Health Regulation 2012,we maintain a register of water cooling systems within the Local Government Area.
The owner of a property where a new cooling tower device is installed, is required to notify and provide information to Council on the device and install the device according to the AS/NZS 3666.1 1995. You must complete the Cooling Tower registration form.
For more information contact Council's Environmental Health Team on (02) 9839 6055.