Information on the most widely used ASTM standards within the materials testing industry
ASTM D1424 Standard Test Method for Tear Strength of Fabrics by Falling-Pendulum (Elmendorf) Apparatus
ASTM D1424 specifies the procedure for determining the force required to propagate a single tear through a fabric using the Elmendorf (falling-pendulum) tester. The test method is a single-tear (tongue) test. A rectangular specimen is slit partway along its length to create two tongues. The tear propagates from the slit across the width of the specimen.

Test Principle of ASTM D1424:
A pendulum is raised to a fixed height, storing gravitational potential energy.
1. The pendulum is released and swings, impacting a pre-notched fabric specimen.
2. The pendulum’s kinetic energy loss equals the work done to tear the fabric.
3. A pointer or digital sensor measures the residual swing angle, converting it to tear force (N/gf).
4. The result reflects resistance to sudden, impact-driven tearing (not slow tensile tearing).
Test Equipment required:
| Elmendorf tear tester (ballistic pendulum machine) | Include: Pendulum Assembly: Weighted pendulum (interchangeable masses for different force ranges: 0–16 N, 0–32 N, 0–64 N, etc.) Clamping System: Stationary lower clamp + pendulum-mounted upper clamp; ensures straight tear path; Reading System: Mechanical pointer + scale or digital encoder with display; records peak tear force;
|
| Sample preparation tools | Precision sharp cutter make make a 12.7 mm (0.5 in) pre-slit; leaves 43 ± 0.15 mm tear length. Template for specimen cutting. Conditioning cabinet (per ISO 139) |
ASTM D1424 Test Specimen Information:
| Item | Description |
|---|---|
| Shape & Dimensions | Rectangular: 100 mm long x 63 mm wide (Optionally, 76 mm wide for some fabrics). A 43 mm slit is cut from the center of one 63 mm (or 76 mm) edge.
|
| Quantity | A minimum of 5 specimens for the warp (lengthwise) direction and 5 for the filling (crosswise) direction. |
| Preparation | Specimens must be cut with their long dimension parallel to either the warp or filling yarns. Edges must be clean-cut and parallel. Avoid selvedges or areas with distortions. |
| Conditioning | Specimens must be conditioned and tested in a standard atmosphere (e.g., 21 ± 1°C, 65 ± 2% RH) as per ASTM D1776. |
Test procedure:
1. Select the pendulum mass so that the measurement value falls within 15% to 85% of the scale range. Check the zero position of the instrument and raise the pendulum to the starting position.
2. Secure the fabric sample by placing it in the clamp, ensuring that the long side of the fabric is parallel to the upper edge of the clamp. Clamp the fabric in the center of the clamp with the bottom edge against the bottom of the fixture. Use a cutter to make a 20±0.5mm notch so that the length to be torn is 43±0.5mm.
3. Press down the pendulum stopper to release the pendulum. When the pendulum swings back, stop it without interfering with the pointer position. Read the measurement in N from the scale or digital display. Depending on the type of instrument used, multiply the scale reading by the appropriate factor to convert it to a result in newtons. Check that the result is between 15% and 85% of the full scale, and repeat the test for at least five fabric samples in each direction.
4. Observe that the tearing process occurs along the direction of the force. The following conditions are considered correct: a) No yarns slip out from the fabric; b) No slippage occurs in the clamp; c) After complete tearing, the notched area remains within a width of 15mm. Otherwise, the result should be discarded.
5. If three or more test results are rejected, this method is not applicable.
6. Test Results
a) The average tearing strength in the warp and weft directions, expressed in N. If only 3 or 4 fabric samples are properly torn, record the tearing strength results of the properly torn samples separately.
b) If required, record the coefficient of variation of the tearing strength, expressed as a percentage.
c) If required, record the 95% confidence interval of the tearing strength, expressed in N.
d) If required, record the minimum and maximum tearing strength in each direction, expressed in N.
Related test standard of ASTM D1424:
| ISO 13937-1 | Textiles - Tear properties of fabrics - Part 1: Determination of tear force using ballistic pendulum method (Elmendorf) |
| GB/T 3917.1 | Textiles.Tear properties of fabrics.Part 1:Determination of tear force using ballistic pendulum method(Elmendorf) |
| ISO 13937-2 | Determination of tear force of trouser-shaped test specimens (Single tear method). |
| ISO 13937-3 | Determination of tear force of wing-shaped test specimens. |
| ISO 13937-4 | Determination of tear force of tongue-shaped test specimens (Double tear test). |
| JIS L 1096 8.17.4 | Method D (Pendulum Method) is mainly applied to textiles as Elmendorf tear methods. |
| ISO 1974 | Paper - Determination of tearing resistance (Elmendorf method) |
| ASTM D5734 | Standard Test Method for Tearing Strength of Nonwoven Fabrics by Falling-Pendulum (Elmendorf) Apparatus |
Importance for the Textile Industry
Durability & Performance: Tear strength is a critical mechanical property; directly impacts fabric lifespan and resistance to snags/pulls during use.
Quality Assurance: Ensures consistency in raw materials and finished goods; identifies production defects (e.g., weak yarns, poor weaving).
Safety Compliance: Mandatory for protective clothing, industrial fabrics, and airbags—prevents catastrophic failure under impact.
Trade Uniformity: Standardized method reduces disputes in North American and global textile trade.
Material Selection: Guides R&D for high-performance fabrics (e.g., outdoor, military, medical) by comparing tear resistance across materials/processes.
Regulatory & Customer Requirements: Meets specs for brands, retailers, and government procurement.
Related products and device
Related Standard
ISO 13937-1 Textiles - Tear properties of fabrics - Part 1: Determination of tear force using ballistic pendulum method (Elmendorf)
ISO 13937‑1 is the ballistic pendulum (Elmendorf) method for measuring fabric tear force under sudden impact. It is the most widely used impact‑style tear test for woven fabrics, giving a single‑rip tear propagation force value.It is known as the single tear method.
ASTM D4533 test used to measure the force required to continue or propagate tearing in woven or non-woven geotextiles, using the trapezoidal method for testing. The trapezoidal tearing method is a test that generates tension along a reasonably defined path, allowing the tear to propagate across the width of the specimen. The trapezoidal tear strength of woven fabrics is mainly determined by the characteristics of the yarns clamped in the fixture.
ISO 13934-2 Tensile properties of fabrics (grab method)
ISO 13934-2 specifies a procedure for the determination of the maximum force of textile fabrics known as the grab test. The method is mainly applicable to woven textile fabrics including fabrics which exhibit stretch characteristics imparted by the presence of an elastomeric fibre and mechanical or chemical treatment. It can be applicable to fabrics produced by other techniques.
It is not normally applicable to geotextiles, nonwovens, coated fabrics, textile-glass woven fabrics, and fabrics made from carbon fibres or polyolefin tape yarns. The method specifies the determination of the maximum force of test specimens in equilibrium with the standard atmosphere for testing and of test specimens in the wet state. The method is restricted to the use of constant-rate-of-extension (CRE) testing machines.
FAQs about ASTM D1424 (Elmendorf tear test)
Q1: What is ASTM D1424 mainly used for?
A: It is the international standard test method for measuring the tear force of fabrics using the ballistic pendulum (Elmendorf) method. It determines how much impact force is needed to propagate a pre-cut slit in a fabric.
Q2: Why test both warp and weft directions?
A: Woven fabrics are anisotropic—tear resistance is usually different in machine (warp) and cross‑machine (weft) directions. Both must be reported for complete performance.
Q3: What factors affect the test results?
A: Fabric structure (yarn, weave, density), pre‑conditioning (temperature & humidity), pre‑cut length, pendulum range, clamping tightness, and test direction.
Q4: Why is tear strength important for fabrics?
A: Tear strength is a critical indicator of durability and serviceability. A fabric with high tear resistance will last longer, resist damage from snagging or puncturing, and is essential for safety in applications like protective workwear, tents, parachutes, and upholstery.
Q5: What is the main difference between ISO 13937-1 and ASTM D1424? Aren't they both Elmendorf tests?
A: Yes, both use an Elmendorf pendulum, but they are not directly comparable due to key differences:
Specimen Size: ISO uses a 100mm x 75mm specimen with a 20mm slit. ASTM uses a 100mm x 63mm (or 76mm) specimen with a 43mm slit.
Results: The different geometry affects how the tear propagates. Therefore, a fabric will yield different numerical values for each standard. You must test and report according to the specific standard required by your buyer or specification.
Q6: How many specimens do I need to test?
A: The standard requires a minimum of 5 specimens in the warp direction and 5 in the weft direction. Testing both directions is crucial because fabric strength often differs significantly between them.
Q7: What are common reasons for high variation in test results?
A: High variation (coefficient of variation) can be caused by:
Improper Specimen Cutting: Specimens not cut precisely parallel to the yarns.
Fabric Irregularities: Slubs, thick/thin places, or uneven weave.
Clamping Errors: Misalignment of the slit with the clamp edges, or inconsistent clamping pressure.
Conditioning: Testing fabric that has not been properly conditioned to the standard temperature and humidity.
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