ASTM International Standard Specification for Greige Woven Glass Fabrics ASTM D579/D579M-10

This specification covers the general and physical requirements for greige fabrics woven from “E” electrical glass fiber yarns. The yarn shall be a continuous filament, free of any free alkali metal salts, such as soda or potash, and foreign particles, dirt, and other impurities. The fabric shall be furnished in rolls and shall be wound in spiral tubes. The materials shall be tested and shall conform to the following requirements: fabric count; yarn numbers for both the warp and filling yarns; filament diameter; strand construction; twist direction wherein the primary twist in the singles strands shall be “Z” twist and the final twist in the plied yarns shall be “S” twist; twist level; fabric weave type which shall include crowfoot, leno, mock leno, plain, eight-harness satin, and twelve-harness satin; mass per unit area; thickness; breaking strength; width including both selvages but excluding any feathered edges; fabric roll length, length between splices, and number of splices per roll; and ignition loss. The fabrics shall also be examined for defects such as bias or bowed filling; baggy, ridged, or wavy cloth; cut or tear; hole; spots, streaks, or stains; foreign inclusions; tender or weak spot; smash; broken, missing ends or picks; floats and skips; light and heavy marks; crease; waste; weave separation; brittle or fused area; selvage defects; selvage leno ends out; and feather edges.