Chlorine dioxide has the ability to penetrate and remove biofilm formed and kill bacteria, spores and viruses,Chlorine dioxide is usually generated by one of three methods, each of which are both efficient and cost effective viz. by Chlorine Gas method, Sodium Hypochlorite method and by acid activation of Sodium Chlorite. The three methods are explained below in option I, Option II and Option III. In each method Chlorine Dioxide is generated at site through a specialized ClO2 generator.