ISO 4915:1991

Overview

ISO 4915:1991 - Textiles - Stitch types - Classification and terminology is an ISO International Standard that classifies, designates, describes and illustrates stitch types used in hand- and machine‑sewn seams. This second edition (1991) replaces the 1981 edition and provides a standardized nomenclature and symbol system intended as a descriptive reference (not a performance specification). The Standard supports clear communication about stitch construction across garment manufacturing, procurement and textile machinery sectors.

Key Topics

• Scope and purpose: Descriptive guide to identify and reference stitch types used in sewn articles.
• Definitions: Clear terms such as stitch, stitch type, intralooping, interlooping and interlacing.
• Classification system: Six major stitch classes identified by the first digit of a three‑digit code:
  • Class 100 - Chain stitches (intralooping)
  • Class 200 - Stitches originated as hand stitches (single thread)
  • Class 300 - Lockstitches (interlacing of two or more thread groups)
  • Class 400 - Multi‑thread chain stitches (interlooping of groups)
  • Class 500 - Overedge chain stitches (loops pass around material edge)
  • Class 600 - Covering chain stitches (cover both surfaces)
• Designation rules: Three‑digit numbering for individual stitch types; combinations represented by dot‑separated codes (e.g., 401.502) and parenthesis when formed in one operation (e.g., (401.502)).
• Illustration conventions: Perspective drawings, thread numbering (needle threads 1,2,3…; under‑threads a,b,c…; cover threads A,B,C…), and graphical conventions to clarify thread functions.

Applications

• Standardizes terminology for product specifications, technical documentation and purchase orders involving stitch types.
• Supports quality control and inspection by providing unambiguous stitch identification.
• Helps garment manufacturers and pattern engineers select appropriate stitch constructions for strength, elasticity and edge‑finishing requirements.
• Useful to sewing machine manufacturers and maintenance teams for machine setup and thread path documentation.
• Educational resource for textile students and researchers studying stitch mechanics and seam construction.

Who uses ISO 4915:1991

• Purchasing officers and spec writers
• Garment and textile manufacturers
• Sewing machine designers and OEMs
• Quality assurance and inspection teams
• Textile educators and students

Related Standards

• ISO 4916:1991 - Textiles - Seam classification and terminology (referenced for seam classification and complementary to ISO 4915)

Keywords: ISO 4915:1991, stitch types, stitch classification, stitch terminology, textiles, chain stitches, lockstitches, overedge, covering stitches, seam classification.