Other risk systems

In addition to cooling towers, hot and cold water systems and spa pools, there are a number of other risk systems, e.g. humidifiers, air washers, emergency showers, eye wash sprays, indoor ornamental fountains, aqueous tunnel washers etc that could potentially be a source for legionella bacteria growth.

There is a reasonably foreseeable legionella risk if your water system has any of these factors:

• has a water temperature between 20–45 °C,
• creates and/or spreads breathable droplets, e.g. aerosol
• stores and/or re-circulates water
• likely to contain a source of food for the organism, e.g. presence of sludge, scale or fouling

The actions you need to take with regard to other risk systems are detailed in L8: Appendix 1 - Checklist 3 of Legionnaires’ disease: The control of Legionella bacteria in water systems.

You will need to carry out a risk assessment as described in What you must do to decide whether further actions are needed.

These systems and any others found to present a risk should be maintained in a clean state and monitored on a regular basis, where appropriate. There is also a duty to maintain records of all maintenance carried out together with monitoring results.

"Legionella in aqueous tunnel washers" highlights the risk of exposure to Legionella from aqueous tunnel washers. It details the type of equipment involved in the first known outbreak and outlines key issues that are likely to be applicable in similar plant.