Calibration and validation of the mini-fiber EC image analysis instrument mean fiber diameter through direct or primary measurements

The Minifiber EC (MFEC) is a portable instrument for measuring the diameter of animal fibers. Its accuracy and precision have been estimated but by comparing its measurements with those of laboratory devices that had been calibrated on other devices in turn, not on a direct or primary measure of diameter. This work attempts to test direct measurements by gravimetry, Vernier mini caliper, microscope and the classic microprojector, using a non-deformable, high resistance synthetic fiber (Kevlar) for direct measurement. The MFEC instrument is calibrated with each mean fiber diameter obtained in direct measurements and its results are compared. The conclusions drawn are that it is possible to calibrate the MFEC instrument with direct measurements on Kevlar and measurement accuracy or tolerance of 0.28 microns is obtained. This indicates a very low biased mean fiber diameter measurement by MFEC.