Textile Testing, Quality Control and Care
What this domain tests
Testing and quality questions ask you to select the right test, interpret a result and apply a care label. They also test the 4-point inspection system and standard bodies.
Core rules
- Fibre identification: burn test (cotton smells of paper; polyester melts and beads), solubility and microscopic appearance.
- Performance tests: tensile and tear strength, bursting, abrasion, pilling, dimensional stability, colourfastness to washing, light, rubbing and perspiration; GSM; EPI/PPI; drape and stiffness; air permeability.
- Standards: ISO, ASTM, IS (Bureau of Indian Standards) and AATCC; fastness is rated against grey scales (1–5, with 4–5 often a minimum for apparel).
- Quality control: 4-point fabric inspection. Defects are scored by length: up to 3 in = 1 point, 3–6 in = 2, 6–9 in = 3, over 9 in = 4. Points per 100 square yards are calculated; many apparel programmes accept ≤40.
- Care: ISO 3758 symbols for wash, bleach, dry, iron and professional care.
Worked example
A roll is 120 yards long and 45 inches wide, with 60 penalty points. Area = 120 × 45 ÷ 36 = 150 square yards. Points per 100 square yards = (60 ÷ 150) × 100 = 40. Reasoning: the 4-point system normalises by area, not length, so wide rolls are not unfairly penalised. A result of 40 is at the common acceptance limit; the buyer's AQL and defect type may still reject it.
Traps
Using length instead of area for 4-point calculation; rating fastness without conditioning; confusing Ne and Tex; treating a 4–5 grey-scale result as a fail when the standard requires 4; ignoring shade variation under different light sources.