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