Overview
EN ISO 18103:2015 (CEN adoption of ISO 18103:2015) specifies the requirements for the “Super S” labelling code used on finished woven fabrics made from pure virgin wool. It defines the maximum allowable mean fibre diameter for each Super S grade and prescribes the sampling and test method to determine compliance. The standard is intended to ensure consistent, verifiable claims about superfine wool fabrics and to protect manufacturers, retailers and consumers from misleading labelling.
Key topics and technical requirements
- Scope: Applies to finished woven fabric produced wholly from shorn sheep or lamb wool (pure virgin wool).
- “Super S” grades: Each Super S code has a maximum mean fibre diameter. Examples:
- Super 100s - max 18.50 µm (+0.25 µm tolerance)
- Super 120s - max 17.50 µm (+0.25 µm tolerance)
- Super 150s - max 16.00 µm (+0.25 µm tolerance)
- Super 200s - max 13.50 µm (+0.25 µm tolerance)
- Super 250s - max 11.00 µm (+0.25 µm tolerance)
(Full Table 1 in the standard lists all Super S values.)
- Tolerance: A positive tolerance of +0.25 µm is established as inherent in the test method; the method’s overall result tolerance is (+/–) 0.5 µm, with the negative half not applied to maximum-spec checks.
- Permitted non-wool content: Up to 5% by weight of non-wool yarn for decorative effects is allowed in fabrics bearing a Super S label.
- Test method: Determination of mean fibre diameter is carried out in accordance with ISO 137 (projection microscope method). Key sampling/preparation rules:
- Minimum of three separate squares taken, representative of the fabric or garment.
- Sample squares typically between 3 cm × 3 cm and 5 cm × 5 cm (±0.02 cm tolerance), trimmed to warp/weft.
- Unravel whole warp and weft threads, prepare snippets ≈ 0.4 mm and mount using a fibre microtome as per ISO 137.
- Final value = overall mean of mean values from each slide.
Applications and who uses it
- Textile manufacturers and weavers - for correct Super S labelling of woven wool cloth.
- Garment makers and retailers - to validate fabric claims and to label garments with Super S codes.
- Testing laboratories - for fibre diameter testing and certification using ISO 137 procedures.
- Quality assurance and compliance teams - to prevent misleading labelling and comply with trade practices.
- Purchasers and consumers - to make informed choices about superfine wool products.
Related standards
- ISO 137 - Wool - Determination of fibre diameter - Projection microscope method (normative for testing).
- CWA 16336:2011 - predecessor workshop agreement referenced in the standard.
- IWTO Fabric Labelling Code of Practice - historical basis referenced in the Introduction.
Keywords: EN ISO 18103:2015, Super S, superfine wool, labelling, mean fibre diameter, ISO 137, wool fabric testing, pure virgin wool, woven fabric sampling.