Fabric guide · Updated
ISO textile tests: what the numbers on a spec sheet mean
Breaking force, Martindale abrasion, pilling grade, dimensional change and colour fastness: how each is measured by ISO methods and how to read the result.
Every quality figure on a Woolentex spec sheet is measured by an international ISO method. Because the method is the same everywhere, a buyer in Tashkent, Istanbul or Berlin can compare our results with any other mill's, or recheck them in any accredited laboratory.
The tests, one by one
| Property | ISO method | How the result reads |
|---|---|---|
| Mass per unit area | ISO 3801 | g/m². The weight class of the cloth: under 230 for summer, over 270 for winter. |
| Breaking force | ISO 13934-1 | Newtons, warp and weft separately. Higher means stronger seams. |
| Abrasion (Martindale) | ISO 12947-2 | Cycles to breakdown. Uniform cloth usually needs tens of thousands. |
| Pilling (Martindale) | ISO 12945-2 | Grade 1 to 5; 5 means no pills. |
| Dimensional change | ISO 5077 with ISO 6330 | % change in warp and weft after washing; negative means shrinkage. |
| Colour fastness | ISO 105 series | Grades 1 to 5 (light 1 to 8) per condition; higher is better. |
Why ISO
ISO methods are the shared language of the textile trade. A result stated as "ISO 12947-2: 40 000 cycles" means the same thing to every buyer and every laboratory.
For the most reliable results, testing is done in a laboratory accredited to ISO/IEC 17025. The mill's technologist should review this article before launch.