Chlorine dioxide (ClO2) has quite different properties than chlorine (Cl2). Chlorine dioxide is used as an advanced disinfectant for water and waste water treatment, as well as for disinfection of swimming pools. Unlike chlorine, it does not produce carcinogenic chlorinated organic compounds as a by-product of the disinfection process. For drinking water applications, chlorine dioxide technology has operational advantages over UV disinfection and standard chlorination, while operating at a comparable cost level. Chlorine dioxide has a long lasting disinfection effect through the residual concentration – something that neither chlorine, ozone, nor UV can provide.