Denier (D) Frequently Asked Questions
Short answers to the questions buyers ask most often about Denier (D).
What does it mean?
weight in grams of 9000 metres of filament yarn. Working figures for Denier (D) normally sit around 20-150 denier in activewear in mainstream production. Note ASTM D1907 yarn number on the tech pack so nobody tests against an older revision.
What value should be specified?
Start from 20-150 denier in activewear and adjust for the end use of the garment. Record elastane content alongside Denier (D), because blends shift the measured value. A result outside 20-150 denier in activewear usually points to process drift rather than to the fibre itself.
How is it tested?
ASTM D1907 yarn number. Keeping reference values for Denier (D) lets suppliers quote without extra sampling rounds. Ask for conditioning details together with ASTM D1907 yarn number, since both affect the reading.
Why does it change between lots?
Process variables such as finishing temperature and elastane batch cause the normal spread of results. Working figures for Denier (D) normally sit around 20-150 denier in activewear in mainstream production. Note ASTM D1907 yarn number on the tech pack so nobody tests against an older revision.
Can results be compared across suppliers?
Only when the same standard revision and conditioning are used; otherwise measurements are not equivalent. Record elastane content alongside Denier (D), because blends shift the measured value. A result outside 20-150 denier in activewear usually points to process drift rather than to the fibre itself.
