Last month's message about changes to the ASTM F1506 standard explained that the laundry shrinkage requirements had been revised in this year's edition. Now, the garment manufacturer specifies the shrinkage requirement and test method.
There is another new option within the latest edition of the standard. Section 7.5.1 describes a default value and procedure for laundry shrinkage of 5% maximum after 5 launderings by AATCC 135 (3, IV, Aiii). This default is included in the standard for occasions when a garment manufacturer has not established a specification, allowing a new fabric to be tested for conformance to F1506.
It is important to note that the 5% should not be considered a maximum value for shrinkage or an across-the-board value for all products. It is only included to allow a fabric to be tested for compliance to the standard in the absence of a specification from the garment manufacturer. The garment manufacturer's specification will always supersede the default value and test method.