Overview
EN ISO 17696:2018 - titled Footwear - Test methods for uppers, linings and insocks - Tear strength (ISO 17696:2004) - specifies a laboratory test method for assessing the tear strength of footwear uppers, linings, insocks or complete upper assemblies, irrespective of material. The method quantifies the force required to initiate and propagate a tear so manufacturers and test laboratories can assess material suitability for end use.
Key topics and technical requirements
- Scope: Applies to sheet materials, leather, made-up uppers and finished footwear; assesses suitability for end use.
- Specimens and sampling: Six test specimens are cut-three with the slit parallel to the material’s along (backbone/warp) direction and three perpendicular. For shoe uppers the along direction follows the X‑axis defined in EN 13400.
- Conditioning: Specimens shall be conditioned in a standard atmosphere per EN 12222 (24 h) before testing.
- Apparatus: Requires a tensile testing machine with jaw separation rate of 100 mm/min ± 10 mm/min, an appropriate force range (0–500 N usually suitable), continuous force recording to better than 2% accuracy (class 2 per EN ISO 7500‑1), and cutting tools (press knife) for specimen preparation.
- Test procedure: A single‑slit specimen is clamped with each leg in opposing jaws and torn until the tear reaches an edge. Record:
- Initial peak force (if present) - force to initiate tear
- Maximum tear force - peak during tear propagation
- Median force - average force to continue the tear (derived from force/extension trace)
- Failure classification: Note tear types - normal (clean tear) or abnormal (e.g., coating separating from base, yarn pull‑out, lateral tearing). Abnormal failures may trigger repeat tests or result inclusion per the standard.
- Results and reporting: Calculate arithmetic mean values for each test direction and failure type. Test reports must include mean forces, failure types, material and style descriptions, number of specimens, test date, and any deviations.
Applications and users
- Footwear manufacturers and R&D teams assessing new uppers, linings or insock materials
- Third‑party test laboratories validating material performance and QA checks
- Material suppliers evaluating product specifications and comparisons
- Regulatory and procurement specialists specifying performance requirements for footwear
Related standards
- EN 12222 - Standard atmospheres for conditioning and testing footwear
- EN 13400 - Sampling location, preparation and conditioning of samples
- EN ISO 7500‑1 - Verification of static uniaxial testing machines
- Supersedes EN 13571:2001
Keywords: EN ISO 17696:2018, tear strength, footwear uppers, linings, insocks, test method, tensile testing machine, specimen conditioning, median force.
