Cooling Towers and Warm Water Systems
Cooling towers are often found on the roof of buildings. They cool warm air from an air conditioner by passing the air through an aerated chamber. The warm air can create a favourable environment for the growth of Legionella and other bacteria.
Warm water systems are designed to heat and deliver water at a temperature of less than 60°C and are often found in places where they are used to minimise the risk of scalding, such as nursing homes, childcare centres and hospitals. As a result, the water temperature is suitable for Legionella and other bacteria to grow.
What is Legionella?
Legionella is a bacterium, and there are several species of Legionella that can cause a type of pneumonia called Legionnaires Disease. The bacteria Legionella pneumophila is known to exist in air cooling towers and warm water systems and exposure to airborne water droplets or mists containing the bacteria can result in Legionnaires Disease. It can take between two to ten days for the symptoms to appear and the symptoms include headache, chills, rapid onset of fever, cough and other flu-like symptoms. Legionnaires Disease can be a life-threatening disease. It is not transmitted from one person to another.
Legionella bacteria multiply rapidly at their preferred temperatures of 20°C - 45°C, which means that warm water systems, cooling towers and air conditioners are favourable for the growth of these pathogens. The growth of Legionella bacteria may be prevented by sufficient cleaning, disinfection and maintenance of such systems.
Requirements for Cooling Towers & Warm Water Systems
Council regulates cooling towers and warm water systems under the Public Health Act 2010 and the Public Health Regulation 2012. These systems must also comply with AS/NZS 3666.1:2002, AS/NZS 3666.2:2002 and AS/NZS 3666.3:2000. Owners/occupiers are required to ensure that all cooling towers and warm water systems meet the requirements of the Australian Standards and the NSW Code of Practice for the Control of Legionnaires Disease). Council does not regulate domestic air conditioners and hot water cylinders under this legislation.
Inspections of Cooling Towers and Warm Water Systems
Inspections are carried out by Council’s Environmental Health Officers on an annual basis during the warmer part of the year or on a more frequent basis if a system is found to be non-compliant. The fees are outlined in Council’s Revenue Policy. Please contact Council’s Environmental Health Officer on (02) 6962 8100 or visit NSW Health’s website for more information on cooling towers and warm water system testing.
Griffith City Council Legionella Management Plan
Griffith City Council has developed a Legionella Management Plan to guide Council to assess, regulate and manage the selection, design, installation, operation and maintenance of new and existing cooling towers and warm water systems. Click here to view the management plan.
Effective management of cooling towers and warm water systems is an important consideration for the public health of Griffith City Council residents and the environment in which they reside. It requires the active involvement of both the Council and landholders. Within the Griffith City Council area there is over 100 water cooling systems registered with Council.