Ozone can be measured online using UV spectroscopy – a distinct advantage over traditional ozone measurement methods as it is specific and low maintenance.

In applications such as pre-treatment of raw water, or disinfection of water intended to be consumed by the general population, online ozone measurement is used to ensure sufficient amounts of ozone are being added. The traditional method for measuring ozone online is an amperometric sensor with a membrane. This membrane will need replacing regularly. An ozone sensor which has no replacement parts reduces maintenance and by using multiple UV wavelengths, any interference associated with organic carbon that absorbs UV light in the same region can be eliminated.

In this paper, the use of multiple wavelengths to measure ozone and organic carbon are discussed within the context of different types of drinking water. Such a technique is used in the s::can ozo::lyser.