1.1 This method determines the dimensional change in textile materials subjected to an appropriate combination of specified washing, drying and restoration procedures (Note 1). 1.1.1 Washing Procedures Procedure I Low temperature (40 degrees C), low mechanical action, neutral soap Procedure 11 Medium temperature (50 degrees C), low mechanical action, soap and alkali Procedure 111 Medium temperature (50 degrees C), moderate mechanical action, soap and alkali Procedure IV High temperature (70 degrees C), moderate mechanical action, soap and alkali. 1.1.2 Drying Procedures A - Drip-dry B - Flat-bed press C - Flat dry D - Line dry E - Tumble dry. 1.1.3 Restoration Procedures 1 - Tension Presser 2 - Knit Shrinkage Gauge 3 - Hand iron. 1.2 Before using this method, the combination of procedures suitable for the particular item to be tested must be selected to arrive at the appropriate test. A complete test consists of a washing, drying and, if necessary, a restoration procedure. For example, Test II.B.1 means that the textile material has been washed at 50 degrees C with low mechanical action, and soap and alkali, dried by flat-bed press and restored by tension pressing. The final result obtained will, of course, depend upon the choice of test conditions used. 1.3 The four washing tests specified vary in severity of operating conditions and correspond in their essentials to procedures commonly used in commercial laundries. The five drying procedures specified provide appropriate methods
for drying different textile materials. Three procedures are specified for determining the dimensional restorability of materials after washing and drying for those textiles that may be restored by ironing or wearing. 1.4 This method is suitable for use with woven or knitted fabrics and also with garments and other made-up textile articles. It may not be suitable for use with certain types of fabrics such as those of open construction or
delicate nature (Note 2). 1.5 This method is also applicable to certain nonwoven fabrics. For nonwovens, the principal directions of measurement shall be machine direction and cross direction (perpendicular to the machine direction). Nonwoven fabrics
are not usually subjected to restoration procedures. Note 1: Experience has shown that most relaxation shrinkage occurs in the first wash, two additional washes usually being sufficient to effect complete relaxation shrinkage. Note 2: Mechanical action is the factor most responsible for fabric distortion during washing and this must be considered when choosing the procedure to be used. Where the amount of mechanical action is required to be minimal (e.g., as in hand washing), CAN/CGSB-4.2 No. 25.1-M should be used.