7
Figure 2 shows a suitable ozone injection point for pools or spas using a venturi. It is normally
fitted before the water outlet(s). A venturi inlet is often used to aerate spa water and may be
obtained from pool and spa suppliers in a range of sizes to accommodate different flow rates and
pipe diameters. When correctly installed, the flow of water through the venturi creates a partial
vacuum causing air to be drawn into the water flow. This vacuum may provide enough suction
to pull sufficient air through the ozone generator and eliminate the need for a separate air pump.
Ensure that a suitable check valve is fitted between the ozone generator and the injection point.
GUIDANCE FOR APPLYING OZONE TREATMENT
The concentration of ozone required for an antimicrobial treatment is dependent on the total
quantity of oxidisable material present and must be allowed for. Oxidisable materials, such as
organic matter or mineral salts consume ozone; therefore, more ozone is required for effective
antimicrobial treatment. When fumigating spaces, the more oxidisable material present as dirt or
dust, the greater the concentration of ozone required for effective treatment. Concentrations
suitable for fumigation typically vary between 0.01 and 0.5 parts per million according to
application. Heavily contaminated areas associated with food storage may require higher
concentrations.
Filter
Pool
Pump
Venturi
Ozone inlet
Water flow
Figure 2: Injection point (pool or spa).
