Legionella Info

Effective Legionella control is a total management system that includes, but is not limited to, management of biocide, water temperatures, environmental

conditions and regular maintenance and cleaning. Components and equipment that require maintenance and cleaning include basins, fill pack, drift

eliminators and side stream filters. Twenty risk factors associated with cooling towers are listed in Australian Standard AS 3666.3:2000 Air Handling and

Water Systems of Buildings – Microbial Control – Performance based maintenance of cooling water systems. The conductivity level (or increasing cycles

of concentration) is only one factor that can influence Legionella control.   All 20 factors must be considered in a cooling water management program. The

recommendations about cycles of concentration in this guide do not compromise effective Legionella control but will improve the efficient use of water and


Refer to these downloadable documents for further information.