In this test method, a cut is made in a rectangular specimen, which starts a tear. By cutting the material, two “tongues” are formed. A reference line is drawn to indicate the point to tear. One tongue is placed in the upper jaw and one tongue is placed in the lower jaw. As the test is run, the jaws move apart and the fabric tears along the pre-cut segment.

B. Trapezoid Test

The trapezoid tear method is a test that produces tension along a reasonably defined course such that the tear propagates across the width of the specimen. The trapezoid tearing strength for woven fabrics is determined primarily by the properties of the yarns that are gripped in the clamps. In nonwoven fabrics, because the individual fibers are more or less randomly oriented and capable of some reorientation in the direction of the applied load, the maximum trapezoid tearing strength is reached when the resistance to further reorientation is greater than the force required to rupture one or more fibers simultaneously.

Elmendorf Tear Strength
The Elmendorf tear tester determines the tearing strength by measuring the work done in tearing through a fixed length of the test specimen. It consists of a sector pendulum pivoted on anti-friction ball bearings on a vertical bracket fixed on a rigid metallic base. The test principle is fairly simple; the pendulum is lifted up to certain height. When released, the pendulum will have a certain potential energy, at the bottom of the swing the pendulum tears the specimen and the pendulum loses the energy used to tear the sample.