ISO 4916:1991

Overview

ISO 4916:1991 - Textiles - Seam types - Classification and terminology provides a standardized system for classifying, illustrating (cross-sections) and designating stitched seams used mainly in the clothing industry. The standard describes a visual and numeric method to identify seam construction, shows conventions for cross‑section illustrations, and establishes a five‑digit seam designation format. Annex A maps ISO designations to previous national designations. ISO 4916 is intended to be read in conjunction with ISO 4915 (stitch types).

Key topics

• Scope and purpose: Classifies common stitched seams used in garment and textile manufacturing; not exhaustive but covers frequently used seam types.
• Classification system: Seams are divided into eight classes based on the number and configuration of material components (limited or unlimited edges) and their spatial arrangement.
• Designation format: A five‑digit numerical code:
  • 1st digit = seam class (1–8)
  • 2nd–3rd digits = material configuration identifier (01–99)
  • 4th–5th digits = needle penetration/location and mirror image variants (01–99)
• Illustration conventions: Standardized symbols and drawing rules for cross‑sections:
  • heavy line for material layers
  • wavy line for unlimited edges, straight line for limited edges
  • straight lines to show needle penetrations or tangent stops
  • dot to denote piping cross‑section
• Relationship to stitch types: Seam designations must be followed by the stitch type(s) as defined in ISO 4915; where multiple stitch types are used they are listed left to right.

Practical applications

ISO 4916 is useful for anyone involved in textile product specification, production and quality assurance. Typical uses include:

• Garment manufacturers and pattern technologists: specify seam construction consistently across suppliers and factories.
• Purchasing/procurement officers: write clear seam requirements into purchase orders and technical packs.
• Sewing machine and equipment manufacturers: design machines and programming to accommodate specific seam constructions.
• Quality control and inspection: verify that seams meet the documented configuration and needle penetration patterns.
• Training and documentation: teach seam identification and create standardized technical documentation for development and archival purposes.
• Standards bodies and compliance teams: harmonize national designations using Annex A.

Related standards

• ISO 4915:1991 - Textiles - Stitch types - Classification and terminology (normative reference)
• Developed by ISO/TC 38 (Textiles)

ISO 4916 improves clarity in technical communication about stitched seams, reduces ambiguity in specifications, and supports consistent manufacturing and quality control across the textile and apparel supply chain.