The Cusick Test, an essential ISO standard in the textile industry, measures fabric drape through the Drape Coefficient (DC). This method evaluates a fabric’s hanging behavior and aesthetic appeal. It involves suspending a circular fabric sample above a disk, where it naturally forms a shadow. The shadow, measured with specialized lighting and a parabolic mirror, helps calculate the DC as a percentage of the shadow versus the fabric’s flat area. Lower DC values indicate better drape quality. Factors like stiffness, weight, thickness, and composition of the fabric influence the DC, which typically has a ±2% error margin. Renowned for its precision and adaptability to various fabrics, this test is integral for assessing textile quality and appearance.