General Technical Documents The Turbidity Tube: Simple and Accurate Measurement of Turbidity in the Field
Published: 2006-01-20
Turbidity is an important water quality parameter in drinking water provision and treatment. The equipment typically used to measure turbidity can be quite expensive, and often provides results which are more precise and accurate than necessary. This high cost is a barrier to many projects in the developing world. In this paper, we will present the turbidity tube as an alternative device to measure turbidity. A turbidity tube can be purchased commercially, or can be constructed at an extremely low cost using a wide range of locally available materials. It is particularly well-suited to situations when decisions can be made based on approximate turbidity (rounded to the nearest 5 NTU). We give a brief discussion of what turbidity is, how a turbidity tube is constructed, and how to use it properly.