Overview - EN ISO 2078:2022 (Textile glass - Yarns - Designation)
EN ISO 2078:2022 specifies a harmonized system for the designation of textile glass yarns (single, multiple-wound, folded/plied, cabled, textured yarns, strands, slivers and rovings) based on their linear density expressed in the tex system. Adopted by CEN from ISO 2078:2022, this standard replaces earlier editions and defines the information and format manufacturers and users should include in a concise yarn designation.
Key topics and technical requirements
- Designation elements: The condensed technical description includes - where applicable - the glass type, yarn type, nominal fibre diameter (µm), linear density (tex), twist direction and amount (turns per metre), number of components (plying/cabling), and an optional manufacturer’s code.
- Glass type codes: Single-letter codes identify glass composition (from Table 1), e.g. E, D, A, C, S, R, AR, E‑CR, Q, QB, BF, each with specific general indications (electrical properties, alkali resistance, high silica, basalt, etc.).
- Yarn type codes: Letters denote yarn form - C (continuous filament), D (discontinuous/staple), B (binary/composite).
- Linear density unit: Tex is the preferred base unit; multiples or submultiples may be used but must be indicated.
- Formatting rules: The standard follows ISO 1139’s single-to-fold designation rules and provides examples (e.g., EC9 34 Z 40, ED7 190 Z 160, EC9 340 T352) to illustrate common cases like textured yarns, folded yarns, and assembled strands.
Applications and practical value
- Ensures consistent product labeling and clear technical communication across supply chains.
- Facilitates specification, procurement and quality control of glass yarns used as reinforcement in composites and technical textiles.
- Supports traceability and interchangeability between manufacturers, converters and end-users by standardizing the essential technical data in a compact format.
- Useful for technical documentation, batch records and product data sheets where a concise, internationally recognized yarn designation is required.
Who should use this standard
- Glass-fibre yarn and roving manufacturers
- Composite and reinforced plastics producers (design/specification teams)
- Technical textile converters, fabricators and engineers
- Procurement, quality assurance and testing laboratories
- Standards writers and regulatory bodies involved in materials specification
Related standards
- ISO 1139 - Designation of yarns (single-to-fold rules)
- ISO 2 - Direction of twist designation
- ISO 472 - Plastics - Vocabulary
Using EN ISO 2078:2022 helps organizations communicate yarn properties unambiguously, improving interoperability and reducing errors in material selection and specification.
