Overview
EN ISO 18403:2016 / ISO 18403:2016 specifies a laboratory test method to determine the maximum lateral force a footwear slide fastener (zipper) can withstand during closure without damage. Applicable to all types of slide fastener, the method simulates a slider closing while a sideways load is applied to the stringers to evaluate resistance to damage during closure.
Key topics and technical requirements
- Scope & principle
- Measures the maximum lateral (sideways) force under which a slide fastener will close without failure.
- The slider is moved while incrementally increasing lateral forces until failure, if any, occurs.
- Apparatus essentials
- Two end clamps with parallel clamping edges, separation D = 160–335 mm, and ability to apply (30 ± 5) N longitudinal tension.
- Five pairs of movable side clamps with square edges (25 ± 1 mm wide) arranged perpendicular to end clamps; lateral spacing between clamp pairs ≈ 35 ± 1 mm.
- Moveable clamp to grip the puller and means to move it at (100 ± 25) mm/min.
- Means to apply lateral tensile forces of 20 ± 2 N, 30 ± 3 N, 40 ± 4 N, 50 ± 5 N, 60 ± 5 N to side clamps.
- Specimens and conditioning
- Minimum of three tests at each lateral force level (or until failure).
- Conditioning: 24 h in standard atmosphere per ISO 18454 before testing.
- Number of fasteners required depends on fastener length (e.g., 125–219 mm → 15 fasteners; 400+ mm → 3 fasteners).
- Test procedure highlights
- Mark multiple test positions along the fastener at ~60 mm intervals.
- Apply lateral forces at each position, close the slider through the loaded zone (~60 mm travel), and record whether closure occurs without damage.
- Identify failure modes: separated locked teeth, teeth pulled off stringer, stringer material failure.
- Reporting
- Test report shall include reference to ISO 18403, sample description, date, maximum lateral force with no failure, force at failure and failure type, and any deviations.
Applications and users
- Intended for: footwear manufacturers, component suppliers, zipper (slide fastener) manufacturers, independent test laboratories, R&D teams, and quality assurance departments.
- Practical uses:
- Verify slide fastener durability and safety in shoes and boots.
- Compare materials, slider designs, and zipper constructions under lateral loads.
- Support product development, supplier qualification, and conformity documentation.
Related standards
- ISO 18454 - standard atmospheres for conditioning/testing footwear components (referenced for specimen conditioning).
- ISO 19952 - footwear vocabulary and terms used in this standard.
Keywords: EN ISO 18403:2016, ISO 18403:2016, footwear, slide fasteners, zippers, test methods, resistance to damage, lateral force, slide fastener testing, slide fastener durability.