CAN/CGSB-4.2 No. 58-2004

1. PURPOSE AND SCOPE 1.1 This method determines the dimensional change of textile fabrics or garments, likely to occur in domestic laundering procedures. The fabric specimen or garment is subjected to an appropriate combination of specified washing, drying and restoration procedures.(1) 1.2 Seven washing, six drying and three restoration procedures are included as follows: 1.2.1 Washing Procedures(2) I - Low temperature (40°C), low mechanical action, synthetic detergent II - Medium temperature (50°C), low mechanical action, synthetic detergent III - Medium temperature (50°C), moderate mechanical action, synthetic detergent IV - High temperature (70°C), moderate mechanical action, synthetic detergent V - Cold temperature (20°C), low mechanical action, detergent3 VI - Cool temperature (30°C), low mechanical action, detergent(3) VII - Medium-high temperature (60°C), moderate mechanical action, synthetic detergent. 1.2.2 Drying Procedures A - Drip dry B - Flat-bed press C - Flat dry D - Line dry E - Tumble dry F - Tumble dry without heat. 1.2.3 Restoration Procedures 1 - Tension presser 2 - Knit shrinkage gauge 3 - Hand iron. (1) Experience has shown that most relaxation shrinkage occurs in the first wash, two additional washes usually being sufficient to effect complete relaxation shrinkage. (2) Any other combination of temperature, mechanical action, bleach and detergent may be used, but must be reported. (3) It is recommended that a cold water or liquid detergent be used. 1.3 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 IIB1 means that the textile material has been washed at 50°C with low mechanical action, and synthetic detergent, 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. 1.4 The seven washing tests specified vary in severity of operating conditions and correspond in their essentials to procedures commonly used in home laundering. The six 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. 1.5 This method is suitable for use with woven or knitted fabrics and also with garments and other made-up textile articles. 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. This method may not be suitable for use with certain types of fabrics such as those of open construction or delicate nature. 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 should be used for dimensional change. 1.6 The testing and evaluation of a product against this method may require the use of materials and/or equipment that could be hazardous. This document does not purport to address all the safety aspects associated with its use. Anyone using this method has the responsibility to consult the appropriate authorities and to establish appropriate health and safety practices in conjunction with any applicable regulatory requirements prior to its use.