... ozonation, etc….UV light does not add anything to the water ,such as ,undesirable color ,odor , taste , ... the water is exposed. Exposure time is related to the flow rate, the higher the flow rate, the lower the exposure time or the lower the flow rate, the higher the ... the following are some typical UV transmission rates (UVT) City water supplies850-980‰De-ionized or Reverse Osmosis water950-980‰Surface ...