Colour Fastness to Washing Test Methods and Acceptable Limits
Colour Fastness to Washing is verified through ISO 105-C06 domestic laundering. Knowing how the method works avoids rejecting fabric that actually meets the requirement.
Method overview
ISO 105-C06 domestic laundering defines sample size, conditioning and calculation, so values are comparable only within the same revision. Working figures for Colour Fastness to Washing normally sit around grade 4-5 expected in mainstream production. Note ISO 105-C06 domestic laundering on the tech pack so nobody tests against an older revision.
Result interpretation
Read the value together with construction notes; grade 4-5 expected is only meaningful for similar fabrics. Record elastane content alongside Colour Fastness to Washing, because blends shift the measured value. A result outside grade 4-5 expected usually points to process drift rather than to the fibre itself.

Typical limits
Buyers commonly write grade 4-5 expected with a stated tolerance, then verify against ISO 105-C06 domestic laundering. Keeping reference values for Colour Fastness to Washing lets suppliers quote without extra sampling rounds. Ask for conditioning details together with ISO 105-C06 domestic laundering, since both affect the reading.
Sources of variation
Conditioning time, operator technique and shade all influence the result. Working figures for Colour Fastness to Washing normally sit around grade 4-5 expected in mainstream production. Note ISO 105-C06 domestic laundering 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 Colour Fastness to Washing, because blends shift the measured value. A result outside grade 4-5 expected usually points to process drift rather than to the fibre itself.