BS EN ISO 13937-4:2000

Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Sampling
6 Apparatus
7 Atmosphere for conditioning and testing
8 Preparation of test specimens
9 Procedure
10 Calculation and expression of results
11 Test report
Annex A (informative) - Suggested procedure for sampling
Annex B (informative) - Example of pattern for cutting out
        test specimens from the laboratory sample
Annex C (informative) - Sample calculation of tear force
Bibliography

Describes a double-tear method known as the tongue test, using a test specimen with cuts shaped to form a tongue.

This Part of EN ISO 13937 describes a double-tear method known as the tongue test, using a test specimen with cuts shaped to form a tongue. The tear force measured is the force required to propagate the previously started double tears when the force is applied parallel to the cuts and the fabric tears in the direction of the applied force.

The test is mainly applicable to woven textile fabrics. It may be applicable to fabrics produced by other techniques, e.g. to some nonwovens (with the same under-mentioned restrictions as for the woven fabrics).

In general the method is not applicable to knitted fabrics and woven elastic fabrics.

The method only allows the use of constant-rate-of-extension (CRE) testing machines.

NOTE 1: For other tear test methods using tensile-testing machines part 2 of EN ISO 13937 describes a method known as trouser test and part 3 a wing test method. Part 1 of EN ISO 13937 describes the ballistic pendulum (Elmendorf) method.

NOTE 2: For the trapezoidal test methods see ISO 9073-4 for nonwovens or ISO 4674 for coated fabrics.