Standardized Calculation
Mathematical procedures dictate the methods for determining the commercial mass of textile fibres and yarns based on their moisture regain. The application of ISO 6741-1 allows mills to calculate the correct weight of a linen shipment by adding a standard moisture allowance to the dry weight. This ensures that the buyer pays for the actual fibre content rather than the variable water weight.
The standard specifies the exact percentages to be used for different types of bast fibres.
Commercial Mass Calculation
Because flax is highly absorbent, its weight changes with the humidity of the warehouse or the shipping container. ISO 6741-1 provides a formula to normalize these weights to a standard atmosphere. This prevents the seller from losing money on a dry day or the buyer from paying for excess water on a humid one.
The process involves taking representative samples, drying them to a constant mass and then applying the official commercial regain factor. This factor for linen is typically set at twelve percent. All official weighing certificates must state that the measurement followed these international rules.
Transactional Fairness
Uniformity in weighing practices builds trust between international trading partners. It provides a defensible basis for every invoice issued by the mill.