Preshrinking Test Methods and Acceptable Limits
Preshrinking is verified through AATCC 135 verification. Knowing how the method works avoids rejecting fabric that actually meets the requirement.
Method overview
AATCC 135 verification defines sample size, conditioning and calculation, so values are comparable only within the same revision. Working figures for Preshrinking normally sit around below 3% residual shrink in mainstream production. Note AATCC 135 verification on the tech pack so nobody tests against an older revision.
Result interpretation
Read the value together with construction notes; below 3% residual shrink is only meaningful for similar fabrics. Record elastane content alongside Preshrinking, because blends shift the measured value. A result outside below 3% residual shrink usually points to process drift rather than to the fibre itself.
Typical limits
Buyers commonly write below 3% residual shrink with a stated tolerance, then verify against AATCC 135 verification. Keeping reference values for Preshrinking lets suppliers quote without extra sampling rounds. Ask for conditioning details together with AATCC 135 verification, since both affect the reading.
Sources of variation
Conditioning time, operator technique and shade all influence the result. Working figures for Preshrinking normally sit around below 3% residual shrink in mainstream production. Note AATCC 135 verification on the tech pack so nobody tests against an older revision.
Documentation
Record the standard revision on every report, because older versions can differ from current practice. Record elastane content alongside Preshrinking, because blends shift the measured value. A result outside below 3% residual shrink usually points to process drift rather than to the fibre itself.
