The TAPPIUM 203 standard specifies a method for measuring the dissociation of pulp using the Williams tester. Pulp dissociation refers to the water filtration performance of the pulp water suspension, reflecting the condition of the fibers after pulping or fine grinding. The Williams tester is used to evaluate the water filtration rate of pulp, expressed in the value of dissociation (CSF). This standard is widely used in the inspection of pulping processes in the paper industry, the formulation of papermaking processes, and various pulp and paper experiments in scientific research institutes. It is an indispensable Measuring method for studying pulp and papermaking.