The use of ozone to disinfect swimming pools and spas has been a common practice in Europe for over 50 years. In the past five years, the United States pool and spa industry has become increasingly interested in ozone as a supplemental disinfectant to traditional chlorine and bromine-based water treatment. The reasons behind this include a need to provide exceptional water clarity with minimum chlorine odor and bather discomfort, and the recent media coverage regarding chlorine resistant pathogenic parasites (Cryptosporidium parvum) and bacteria (Legionella pneumophila) that exist within many municipal water systems. Ozone is now used as a disinfectant in the Margaret Bell Pool at the University of Michigan (U-M).

The addition of ozone to the swimming pool treatment system will provide better water quality for the swimmers, including a reduction of the chlorine odor and eye irritation, and improvement of the water clarity as a result of the reduction of the total dissolved solids.

Additionally, a reduction in chlorine usage is expected as a result of the ozonation of the swimming pool water.