Dye Dilution Testing has been utilized on thousands of flow measurement tests worldwide, for many years and done correctly is known as one of the most accurate methods of flow measurement.
A known concentration of dye is injected into water, wastewater or industrial effluent stream at a precise flow rate. The diluted concentration of fluorescence is measured downstream by a highly accurate analytical instrument. The dilution factor is utilized to accurately calculate a flow rate for that specific test section.
It is recommended by many regulatory agencies that permanent open channel flow monitoring systems be calibrated in-situ utilizing the dye dilution method.