Overview
EN ISO 3377-2:2025 - Leather - Physical and mechanical tests - Part 2: Determination of double edge tear load specifies a laboratory method to measure the tear strength of leather using a double-edged (Baumann) tear. Published by CEN/ISO and prepared with IULTCS input, this standard is applicable to all types of leather and is used to produce reproducible tear-load data for quality control, specification and comparison.
Key topics and technical requirements
- Test principle: A rectangular specimen with a shaped hole is torn over turned-up steel holders fitted to a tensile testing machine; the maximum force during tearing is recorded.
- Specimen preparation & sampling: Follow ISO 2418 for specimen position and cutting; cut six test pieces - three with the long edge parallel to the backbone and three perpendicular.
- Conditioning & thickness: Condition specimens per ISO 2419. Measure thickness per ISO 2589 at a specified point and calculate mean thickness.
- Apparatus:
- Tensile testing machine with a suitable force range and force-measuring accuracy of at least ±2 % (Class 2 of ISO 7500-1).
- Uniform jaw separation speed of 100 mm/min ± 20 mm/min.
- Test-piece holders (steel strips 10 mm ± 0.1 mm wide, 2 mm ± 0.1 mm thick, bent at right angle).
- Press knife for cutting specimens in one operation.
- Procedure: Mount specimen on holders, run the tensile test until tear, record maximum force. Compute the mean tear load (N) for three specimens in each orientation.
- Results: Optionally calculate mean tear strength (N/mm) by dividing mean tear load by mean thickness.
- Test report must include: reference to ISO 3377-2:2025, mean thickness, mean tear loads (parallel and perpendicular to backbone), overall mean, mean tear strength (if required), conditioning atmosphere, deviations from method, test date and sample identification.
Applications and users
- Who uses it: Leather manufacturers, quality control and testing laboratories, R&D departments, footwear and garment producers, upholstery and automotive suppliers, procurement/spec writers and compliance bodies.
- Practical uses: Verifying material suitability for end-use (resistance to tearing in stressed areas), incoming quality inspection, product development, supplier comparisons, contractual specifications and certification testing.
Related standards
- ISO 2418 - Specimen position and preparation
- ISO 2419 - Specimen conditioning and atmosphere
- ISO 2589 - Thickness measurement
- ISO 7500-1 - Calibration/verification of tensile machines (force accuracy)
- Other parts of the ISO 3377 series for complementary tear test methods
Keywords: EN ISO 3377-2:2025, leather testing, double edge tear, Baumann tear, tear strength, tensile testing, leather quality control.