Hydrostatic Head How to Read It on a Lab Report
Laboratory reports present Hydrostatic Head in a compact format. Knowing what each line means prevents misreading.
Definition reminder
water pressure a fabric withstands. Working figures for Hydrostatic Head normally sit around 1000-10000 mm depending on use in mainstream production. Note ISO 811 water penetration on the tech pack so nobody tests against an older revision.
Common report layout
The report states method ISO 811 water penetration, sample description, conditioning, and the measured result. Record elastane content alongside Hydrostatic Head, because blends shift the measured value. A result outside 1000-10000 mm depending on use usually points to process drift rather than to the fibre itself.
Typical result
Values near 1000-10000 mm depending on use usually indicate a conforming lot, assuming the fabric matches the sample submitted. Keeping reference values for Hydrostatic Head lets suppliers quote without extra sampling rounds. Ask for conditioning details together with ISO 811 water penetration, since both affect the reading.
Red flags
Missing revision numbers, unusual conditioning, and results without units all signal unreliable data. Working figures for Hydrostatic Head normally sit around 1000-10000 mm depending on use in mainstream production. Note ISO 811 water penetration on the tech pack so nobody tests against an older revision.
Questions to ask
Ask the laboratory for the standard revision and sample description before accepting or rejecting a result. Record elastane content alongside Hydrostatic Head, because blends shift the measured value. A result outside 1000-10000 mm depending on use usually points to process drift rather than to the fibre itself.
