So what exactly is ozone ? It’s stable oxygen O2 that has picked up an extra atom of oxygen and becomes O3. Scientists call it activated oxygen. At 20-plus miles above Earth, the ozone layer plays a crucial geophysical role in protecting people from excessive solar UV radiation.
Discovered in the 1840s, it wasn’t until 1906 that the first ozone water purification facility was built in France. Today there are over 2,000 similar plants worldwide. Recently Los Angeles built the largest ozone purification plant in the world. The city chose ozone over chlorine because the latter has had a bad health record.
Chlorine has been found to cause various illnesses, from nose and eye irritation to possibly even cancer. A few years ago more than 100 people living in Milwaukee died, and over 400,000 became ill in one cryptosporidium outbreak than chlorine failed to control.