LOW-LEVEL TURBIDITY MEASUREMENTS : A COMPARISON OF INSTRUMENTS

Measurement of the effect of turbidimeter design and calibration method on inter-instrument variability at low turbidity values. The evaluation of the inter-instrument variability of an assortment of six bench-top and four portable turbidimeters is evaluated using four calibration materials. The results suggest that the low level turbidity readings made with different instruments might agree more closely if improvements are made to instrument design standards, possibly through the voluntary standards system.