Water Vapour Transmission (MVTR) Setting It Correctly on a Tech Pack
Water Vapour Transmission (MVTR) should be written into the tech pack with a value, a tolerance and a method. This removes ambiguity from quotations.
Definition to agree
water vapour passing through fabric. Working figures for Water Vapour Transmission (MVTR) normally sit around higher means more breathable in mainstream production. Note ISO 15496 breathability on the tech pack so nobody tests against an older revision.
Target value
Open the specification at higher means more breathable, adjusted to the end use. Record elastane content alongside Water Vapour Transmission (MVTR), because blends shift the measured value. A result outside higher means more breathable usually points to process drift rather than to the fibre itself.
Method line
Always pair the target with ISO 15496 breathability so the mill and the laboratory test the same way. Keeping reference values for Water Vapour Transmission (MVTR) lets suppliers quote without extra sampling rounds. Ask for conditioning details together with ISO 15496 breathability, since both affect the reading.
Tolerance line
State plus or minus limits to keep production realistic while protecting the requirement. Working figures for Water Vapour Transmission (MVTR) normally sit around higher means more breathable in mainstream production. Note ISO 15496 breathability on the tech pack so nobody tests against an older revision.
Approval step
Approve the result on pre-production bulk rather than on development fabric only. Record elastane content alongside Water Vapour Transmission (MVTR), because blends shift the measured value. A result outside higher means more breathable usually points to process drift rather than to the fibre itself.
