In 1906, in the city of France the first municipal water purification plant was built which utilized ozone. Today there are over 2,000 plants worldwide using ozone to purify drinking water. Recently, Los Angeles built the largest ozone plant in the world for purification of the city's drinking water supply. This system was chosen over chlorine system because of ozone extraordinary ability to effectively purify water without side effects. Ozone is produced naturally by the sun's ultraviolet light.
Ozone is the most powerful oxidizer that can be used safely to purify water.
Its alternate, chlorine, has been documented to cause illness, irritation of the eyes and nose, swimmers ear, etc. Chlorine is also dangerous to transport and store. Ozone is clearly superior to traditional chemical treatment. Just as nature uses ozone to protect life on earth, we can use ozone to protect ourselves from microorganisms in water and air. It is far more cost effective than traditional chemicals.