In Europe, using ozone for swimming pool and spa disinfection has been quite common. More and more people in the world have realized the advantages of using ozone in pool and spa water treatment.
Because of its strong oxidation and disinfection mechanism, ozone is very suitable for pool water treatment. Experimental result shows, ozone is 3000 times faster to treat water than chlorine.
Ozone is also recognized as “green disinfectant”, since it does not cause undesired by-product.
However, chlorine reacts with organic waste and forms a large number of highly toxic chloro-organic compounds, also referred to as "combined chlorine".