At present, ozone is commonly used in purified water, spring water, mineral water and underground water processing. And CT=1.6 is often applied to tap water treatment (C means dissolved ozone concentration 0.4mg/L, T means ozone retention time 4 minutes).

Drinking water treated with ozone kills or inactivates pathogenic microorganisms including viruses, bacteria, and parasites and removes inorganic trace contaminants found in water systems due to pollution. Ozone treatment also reduces naturally occurring organic compounds such as humic acid and algal metabolites. Surface waters, including lakes and rivers, generally contain higher levels of microorganisms. Therefore, they are more prone to contamination than groundwater and require different treatment regimes.