According to Dubai Municipality guidelines for control Legionella in water systems dated, 25/06/2010.
@ Water Systems have to be kept clean to reduce the nutrients available for bacteria growth. Regular visual inspections should be made at least every month to avoid the build-up of dirt, organic matter or other debris.
@ All Water systems which create a water spray or aerosol and Spa pools must be treated and maintained to minimize the risk of Legionella bacteria contamination.