In the guidelines of the WHO ( World Health Organization ) it is emphasized how the cysts of Giardia and Cryptosporidium are resistant to chlorination, reason for which ozone is indicated as a disinfectant suitable for the inactivation of these colonies .
The German and British Regulations have accepted the recommendations of WHO indicating ozone as one of allowed disinfectants and banned the use of chlorine alone. Starting form the Atlanta Olympics in 1996 the use of ozone is made compulsory for competitions.
Ozone is a very unstable gas at normal ambient conditions, so it cannot be stored but must be produced where and when needed. The ozone production system is made with different components essential for the attainment of good results :
- Air preparation system - the feed gasses are prepared by this system;
- Ozone generation - it changes part of the feed gas (air or oxygen) into ozone;
- Ozone mixing system - it allows ozone to be dissolved in water without residual gasses.