Standard Test Method
International testing protocols established by the wool industry govern the determination of fiber diameter distribution using automated optical instruments. This specific standard, known as IWTO-56, outlines the procedures for operating optical fiber diameter analyzers. It provides a reliable method for measuring wool and other animal fibers.
Fiber Measurement
The protocol describes how to prepare representative test specimens from bulk fiber samples. It requires the use of specialized cutting devices to produce short fiber snippets of uniform length. These snippets are then suspended in a carrier liquid and passed through the measuring beam of the instrument.
Commercial Verification
Trading contracts for raw wool and cashmere often cite this standard to ensure that fiber fineness is evaluated accurately. By following the IWTO-56 method, laboratories generate test certificates that are accepted by international buyers and sellers. This uniform testing reduces the likelihood of trade disputes over fiber quality.
Quality Assurance
Maintaining compliance with the standard requires laboratories to participate in regular round-robin trials. These trials compare the test results of different facilities to ensure that everyone is measuring within acceptable tolerance limits. Proper calibration of the instruments with certified reference materials is a mandatory part of the procedure.
The rigorous nature of these quality checks guarantees that the measured mean fiber diameter and coefficient of variation are precise, forming a solid basis for pricing high-value textile shipments.
