Woven Fabric Weight Tolerances and Linear Metre Yield Calculations
Reconcile woven fabric purchases by calculating linear yield from conditioned mass and usable cuttable width under ISO 3801 and ISO 139 parameters.
Bisfa Moisture Regain
Commercial Allowance
Standardized commercial allowance establishes the agreed percentage of moisture added to the oven-dry weight of synthetic and man-made fibers to determine their invoice mass. The industry uses bisfa moisture regain to establish a uniform base for billing, preventing transactions from being affected by environmental humidity. This standard, set by the International Bureau for the Standardisation of Man-Made Fibres, applies specifically to commercial weight calculations.
It does not govern the actual physical moisture present in a fabric during weaving or finishing.
Fibre Mass
Laboratory technicians dry a specimen to constant mass at high temperatures to strip away all moisture. Once the oven-dry mass is established, the standard percentage value is mathematically added to calculate the commercial mass. For example, polyester has a low regain of one and a half percent, while viscose is much higher at thirteen percent.
This calculation ensures that buyers only pay for the actual fibre content.
Weight Settlement
Commercial invoices use these calculated weights to settle accounts between synthetic yarn spinners and textile weavers. Since fibres absorb moisture during shipping and storage, the gross weight at delivery can be misleading. Standard regain calculations bypass this variation.
They provide a reliable baseline for pricing.
Moisture Control
Spinning mills must balance the moisture during packaging to avoid mold and weight discrepancies. If the actual moisture exceeds the standard regain value, the mill is effectively shipping excess water. The buyer can claim a refund based on dry weight analysis.
This mechanism enforces fair trading.