Stitch classes are designated and identified by the first digit of a “3 digit numeral system”. Type of stitch within each class are designated and identified by 2nd and 3rd digit.
ISO# 101 (Chain stitch):
Stitch formed by a needle thread passing through the material and interlooping with itself on the underside of the seam with the assistance of a spreader. Single thread chain stitch’s are often used for temporary stitching (i.e. basting) or for blind stitching. Particular care is required to prevent runback from the last stitch.
Thread consumption ratio=1:5
ISO# 103 (Blind stitch):
Stitch is formed with one needle thread which interloops with itself on the top surface of the material. The thread passes through the top ply and horizontally through portions of the bottom ply without penetrating the full depth. One thread and a curved needle which passes from left to right, entering and exiting from the same side of the material carrying a needle thread which is intercepted by a blind looper.The thread interloops with itself on the top surface. Particular care is required to prevent runback from the last stitch.
Thread consumption ratio=1: 4.5
ISO# 209 (hand stitch/Machine):
This type of stitch is formed with one thread. It is a machine made version of traditional hand stitching sometimes referred to as Saddle Stitch.
Thread consumption ratio = 1 : 1.4