Turbidity Measurement
The Science Behind Your Turbidity Measurements
The Lovibond® PTV Series of Process Turbidimeters offers four different incident light sources. These different light sources were needed to meet regulatory requirements, which differ across the world. The PTV 1000 WL, PTV 2000 and PTV 6000 variations are approved by the USEPA under the Safe Drinking Water Act and are applicable for use in reporting filter effluent and combined filter effluent turbidities from drinking water plants. The PTV 1000 IR version complies with the ISO 7027 design criteria for turbidity measurement below 40 FNU3. With respect to these three versions of turbidimeters, it is only the light source that differs. Although these four light sources are regulatory approved, they are expected to deliver slightly different results. These differences and their causes will be discussed.
Applications of continuous turbidity measurement in drinking water processing
The monitoring of the indicator parameter turbidity with a limit value of 1 NTU / FNU is one of the legal obligations of the operator of a waterworks and is considered to be complied with if this value is maintained at the waterworks exit. In-house laboratories usually take on these tasks and report the results to the responsible supervisory authority according to a defined sampling plan.
Turbidity Measurement
In pool water, turbidity is an indication for the effectiveness of the filter system and cleaning agents. In drinking water it indicates the possible bacterial growth. In sewage treatment plants the turbidity is an indicator of quality in the cleaning procedures. In industries, turbidity is a quality criterion for products. The cause of turbidity is usually tiny small particles or droplets that do not dissolve in the surrounding liquids.