Overview
EN ISO 3376:2020 - Leather - Physical and mechanical tests - Determination of tensile strength and percentage elongation is a CEN-endorsed ISO method for measuring the mechanical performance of leather. Published May 2020 and prepared with IULTCS input, it specifies how to determine tensile strength, elongation at a specified load, and elongation at maximum force. The method is applicable to all types of leather and is widely used for quality control, specification and comparative testing.
Key topics and technical requirements
- Scope: Method for tensile strength and percentage elongation measurements for all leather types.
- Apparatus requirements
- Tensile testing machine with force-measuring accuracy of at least ±2% (as per ISO 7500-1, Class 2).
- Uniform jaw separation speed 100 mm/min ± 20 mm/min.
- Jaws with a minimum length of 45 mm and clamping that limits slippage to ≤1% of jaw separation at maximum load.
- Means to measure elongation (jaw separation or sensors) and a thickness gauge per ISO 2589.
- Test pieces
- Standard and large test-piece geometries are defined; the standard size is preferred, but the large size is used when slippage cannot be prevented.
- Jaw separations: 50 ± 1 mm for standard pieces, 100 ± 1 mm for large pieces.
- Sampling and preparation
- Sampling according to ISO 2418 and conditioning per ISO 2419.
- Cut six test pieces: three with the long side parallel to the backbone and three perpendicular.
- Measure width at six points and thickness at three points (averaged) before testing.
- Procedure and results
- Test piece extended until a specified force or break; record maximum force (Fmax).
- Results reported as tensile strength, percentage elongation at specified load, and percentage elongation at maximum force.
- The 2020 edition allows a pre-load to apply slight tension before measuring elongation.
Applications and users
- Practical uses: quality control, incoming material inspection, product specification, supplier acceptance testing, R&D, failure analysis and comparative assessments of leather for footwear, upholstery, garments, automotive interiors and accessories.
- Typical users: tanneries, leather goods manufacturers, testing laboratories, procurement/specification engineers, product designers and regulatory/standards bodies.
Related standards
- ISO 2418 - Sampling location for leather
- ISO 2419 - Sample preparation and conditioning
- ISO 2589 - Thickness measurement of leather
- ISO 7500-1 - Calibration/verification of tension testing machines
EN ISO 3376:2020 provides a reproducible, internationally recognized procedure for assessing leather tensile properties - essential for consistent product performance and supplier communication.
