The standard unit has become a 24/7 operational unit whilst retaining all of the original features including: Adjustable output of O3 from 2mg / hr up to 80 mg/hr enables a single Prozone unit to treat rooms from 10m3 up to 150m3. Can reduce bacteria levels by up to 99.5%!. Flexible use of the unit as a portable unit or fixed installation. Modular fan & ceramic plate are easy and low cost to service. Programmable.