AATCC 207-2017 Seam Twist in Garments Before and After Home Laundering.
4. Safety Precautions NOTE: These safety precautions are for information purposes only. The precautions are ancillary to the testing proce- dures and are not intended to be all inclu- sive. It is the user’s responsibility to use safe and proper techniques in handling materials in this test method. Manufacturers MUST be consulted for specific details such as material safety data sheets and other manufacturer’s recommendations. All OSHA standards and rules must also be consulted and followed.
4.1 Good laboratory practices should be followed. Wear safety glasses in all laboratory areas.
4.2 Detergent may cause irritation. Care should be taken to prevent exposure to skin and eyes.
4.3 Manufacturer’s safety recommendations should be followed when operat- ing laboratory testing equipment.
5. Uses and Limitations
5.1 This method is applicable to vertical seams aligned with the side folds of a garment when laid on a flat surface. The folds are used as a reference for seam displacement measurements. The side seams of most garments, and inseams of pants, are typically evaluated.
5.2 This test method is applicable to seams oriented with the vertical direction, regardless of location (e.g., side seams, center seams, inseams, etc.) It is not applicable to seams not oriented with the vertical direction, such as curved seams.
5.3 Seam length, fabric construction, and garment assembly, individually or in combination, influence seam twist. Results obtained from matching seams, with identical seam constructional details (i.e. stitch type, seam shape, stitches/inch, etc.) as, for example, from the left and right sides of an item, may be averaged. However, results obtained from seams with different seam constructional details, even within the same garment, should not be compared, or averaged.
5.4 Different laundering temperatures, machine specifications or load sizes may result in different seam twist results. Use caution in comparing results obtained using different testing parameters.
6. Apparatus and Materials (14.1)
6.1 Conditioning facilities to accom- modate hanging garments and/or drying racks with pullout, perforated shelves for laying garments flat (see 14.2).
6.2 Indelible ink marking pen (see 14.3).
6.3 Tape or rule marked in millimeters, eighths, or tenths of an inch.
6.4 Automatic washing machine (see 14.4), or facilities for hand laundering.
6.5 1993 AATCC Standard Reference Detergent (powder) or AATCC High Ef- ficiency (HE) Standard Reference Liquid Detergent (see 14.3). Detergent with or without optical brightener may be used for this test method.
6.6 Scale with at least 5.0 kg (10.0 lb) capacity.
6.7 Hemmed pieces of bleached cotton sheeting (wash load ballast type 1), or 50/ 50 polyester/cotton bleached plain weave (wash load ballast type 3), 920 × 920 mm (36 × 36 in.), to be used as ballast making 1.8 ± 0.1 kg (4.00 ± 0.25 lb) or 3.6 ± 0.1 kg (8.00 ± 0.25 lb) wash load weight. 6.8 Automatic tumble dryer (see 14.4), or facilities for drip, screen or line drying.AATCC 207 pdf download.