Ozone pool systems – the facts

You’re probably wondering, what is ozone? Ozone is a very reactive gas that can be both a man-made and naturally occurring molecule. It’s used for oxidising, deodorising, bleaching and disinfecting.

Ozone is an effective and powerful oxidiser that has a very short life. The ozonator produces ozone gas that is injected into the pool circulation system to aid the residual sanitiser. Ozone is becoming a popular backup for chlorine systems and saltwater chlorinators.

There are two ways to produce ozone in an ozone pool system:

– UV (ultraviolet) Method – air is passed over a UV bulb; the radiation creates nascent oxygen, which becomes ozone. (Light energy)
– Corona Discharge Method – a pool Ozonator creates a small lighting storm in an air-filled chamber. (Electrical energy)

Both methods produce the powerful oxidiser, ozone, to be inserted into the pool water to aid the residual sanitiser (usually chlorine). Ozone only oxidises the water for a very short period of time.

The addition of ozone treatment in chlorinated pools has been shown to reduce harmful chloramines and reduce chlorine consumption. This is certainly a benefit when used in public pools where high bather loads create increased chlorine demand which can result in high chloramine levels if the chlorine level struggles to maintain a recommended level, commonly around 2 ppm – 4 ppm chlorine residual. When you detect the smell of chlorine in an indoor public pool, it is a sign that there is not enough chlorine in the water. The smell is chloramines, not chlorine. Chloramines are less of an issue in residential pools.

The claim that there can be a safe reduction in chlorine residual levels and still safely sanitise the water needs some scientific backup. Given that the water only gets treated one to two times a day with ozone as it passes through the Ozonator, which is a point of contact sanitiser only, it offers no residual protection for bathers if bacteria or parasites are in the main body of pool water.