These include hypochlorite or hypochlorous acid and hypobromite or hypobromous acid. They are available in powder or liquid form. Automatic feeders are used to add the chemicals directly to water in the pipes. They can be either point of use or point of entry systems. Adequate contact time is essential to ensure disinfection.
Ozone is another chemical oxidant.
It can destroy bacteria in drinking water without creating the taste and odor problems common with chlorine. In addition, many organic compounds can be partially or completely oxidixed by ozone with no formation of chlorinated compounds. The effectiveness of an oxidant can be influenced by water temperature, acidity, concentration of oxidant, contact time with the oxidant prior to water use, and other factors. Pretreatment may be required for turbid water. Sufficient levels of UV radiation must be applied or it may merely retard growth or impede reproduction of bacteria and viruses, rather than destroy these organisms.