1.1 This test method covers the measurement of stiffness properties of fabrics. Bending length is measured and flexural rigidity is calculated. Two procedures are provided. 1.1.1 Option A—Cantilever Test, employing the principle of cantilever bending of the fabric under its own mass. 1.1.2 Option B—Heart Loop Test, employing the principle of a loop formed in a fabric strip and hung vertically. 1.2 This test method applies to most fabrics including woven fabrics, air bag fabrics, blankets, napped fabrics, knitted fabrics, layered fabrics, pile fabrics. The fabrics may be untreated, heavily sized, coated, resin-treated, or otherwise treated. 1.3 The values stated in SI units are to be regarded as the standard. The U.S. customary units may be approximate. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.5 This international standard was developed in accordance with internationally recognized principles on standardi