Modulus Specification Targets for Buyers
Setting Modulus correctly on a tech pack prevents most later disputes. Targets belong on the page before the first fabric sample.
Where to write it
Place Modulus next to composition and weight so all three are quoted as one package. Working figures for Modulus normally sit around 4-8 kPa at 30% extension in mainstream production. Note ISO 13934-1 modulus on the tech pack so nobody tests against an older revision.
Reference level
Typical activewear expectation: 4-8 kPa at 30% extension. Record elastane content alongside Modulus, because blends shift the measured value. A result outside 4-8 kPa at 30% extension usually points to process drift rather than to the fibre itself.
Tolerances that work
Allow a small tolerance rather than a fixed number, since normal process variation exists in every lot. Keeping reference values for Modulus lets suppliers quote without extra sampling rounds. Ask for conditioning details together with ISO 13934-1 modulus, since both affect the reading.
Verification method
Confirm with ISO 13934-1 modulus and keep the report against the bulk record. Working figures for Modulus normally sit around 4-8 kPa at 30% extension in mainstream production. Note ISO 13934-1 modulus on the tech pack so nobody tests against an older revision.
Commercial note
Tightening beyond practical need raises cost without improving garment life, so set the tightest target only where it protects the customer. Record elastane content alongside Modulus, because blends shift the measured value. A result outside 4-8 kPa at 30% extension usually points to process drift rather than to the fibre itself.
