This part of ISO 5264 specifies a method, using a PFI mill, for the laboratory beating of pulp. The description is limited to the sampling and beating of the pulp, the withdrawal and distribution of samples, and the beating equipment. NOTE Beating is a preliminary step in testing the physical properties of pulp. In principle, this method is applicable to all kinds of chemical and semi-chemical pulps. In practice, the method may not give satisfactory results with certain pulps having extremely long fibres.