BS ISO 2648:2020

What is ISO 2648 about? 

ISO 2648  discusses wool. ISO 2648 specifies a method for the determination of fibre length distribution parameters (principally mean length, expressed as Hauteur or Barbe, and the coefficient of variation of the measurement) on slivers and rovings made from combed wool or combed synthetic fibres. 

Note: As the fibres of the different chemical structures have different di-electric values, ISO 2648 is not directly applicable to slivers made up of a blend of wool/synthetic fibres. 

Who is ISO 2648 for? 

ISO 2648 on the determination of fibre length distribution parameters of wool is useful for: 

• Wool manufacturers  
• Quality control personnel  

Why should you use ISO 2648?  

Length is the most important property of fibre. Longer fibres are used to manufacture fine yarns.  Longer fibres are generally more uniform, finer, and stronger than shorter ones. Yarn quality parameters such as strength, elongation, hairiness, and evenness are strongly correlated to the length of fibres. ISO 2648 determines the test methods to determine the fibre length distribution parameters by capacitance method that measures the electrical resistance of the material that passes through two electrodes spaced slightly apart.  

Determination of fibre length distribution parameters by capacitance method is undertaken to improve the quality of the fibre and to protect the fibre from the harmful chemicals that will affect the appearance of the fibre which can impact the marketability of the fibre. 

What’s changed since the last update? 

BS ISO 2648:2020 supersedes ISO 2648:1974. BS ISO 2648:2020 includes some editorial changes with respect to ISO 2648:1974. These include: 

• The title has been modified as "Wool — Determination of fibre length distribution parameters — Capacitance method" 
• The content structure has been updated 
• In the scope, the text for “wool/synthetic blends, principle, conditioning and testing atmosphere, preparation of samples for testing all of these are modified 
• Normative references and terms and definitions respectively have been added, and the subsequent clauses have been renumbered 
• Test specimen clause , definition of the test on top sliver-notes on sampling clause, the former annexes A (Literature reference), annex C (The Almeter), annex D (Control of the machine), annex E (Calibration check of the machine) and annex F (Accuracy of the method), the former Figures 1 to 4, has been deleted 
• Sampling and preparation of laboratory sample”, the procedure for apparatus measuring, digital system, test report, and precision respectively, preparation of top and sliver, the introduction of the precision of the method, Figures A.1 to A.3, a bibliography have been added