This part of GB/T 3903 specifies the test method for determining the shear strength of hook and loop fasteners before and after repeated opening and closing. This section applies to all kinds of footwear Velcro.
GB/T 3903.21-2008 Referenced Document
EN 12240 Touch and close fasteners - Determination of the overall and effective widths of tapes and the effective width of a closure
GB/T 16825.1-2002 Verification of static uniaxial testing machines--Part 1: Tension/compression testing machines--Verification and calibration of the force-measuring system
GB/T 22049 Footwear—Standard atmospheres for conditioning and testing of footwear and components for footwear*, 2019-08-30 Update
GB/T 3903.21-2008 history
2008GB/T 3903.21-2008 Footwear.Test methods for accessories: Touch and close fasteners.Shear strength before and after repeated closing