1.1本试验方法涵盖了使用光纤直径分析仪（OFDA）测定羊毛和其他各种形式动物纤维的平均纤维直径和纤维直径变化的程序。 笔记 1-本试验方法也适用于具有圆形横截面的其他纤维，如一些聚酰胺、聚酯和玻璃；它也可用于有限数量的聚丙烯和再生纤维素型纤维。 笔记 2-在本试验方法的后续章节中，术语 “ 羊毛 ” 适用时也表示其他动物纤维。 笔记 3-有关羊毛、羊毛上衣、马海毛、马海毛上衣、羊驼和羊绒的细度规格，请参阅规格 D3991 , D3992 , D2252 ，以及试验方法 D2816 分别地 1.2 OFDA报告了以微米为单位的平均纤维直径和纤维直径的标准偏差( μ m） 。纤维直径的变异系数以百分比形式报告。 1.3 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全和健康实践，并确定监管限制的适用性。 ====意义和用途====== 本试验方法规定了测量动物纤维平均直径和直径变化的取样和试验程序。 由于目前对实验室间精度的估计是可以接受的，因此本试验方法被认为是令人满意的，适用于原棉和棉条形式的羊毛和其他动物纤维的商业装运验收试验。如果在使用本试验方法进行验收试验时，由于两个或多个实验室报告的值的差异而导致不一致，则应确定实验室之间的统计偏差（如有），每次比较都应基于从被评估类型的一个材料样品中随机抽取的样本进行测试。 试验方法 D2130 应作为参考试验方法。 本试验方法可用于确定是否符合平均纤维直径和直径变化，以在确定装运是否符合规范中给出的材料规范时指定等级 D2252 , D3991 和 D3992 ，以及试验方法 D2816 . 本试验方法和IWTO方法47-98中提供的测定平均纤维直径和纤维直径标准偏差的程序基本一致。

1.1 This test method covers a procedure that uses an Optical Fiber Diameter Analyser (OFDA) for the determination of the average fiber diameter and the fiber diameter variation in wool and other animal fibers in their various forms. Note 1—This test method may also be applied to other fibers having a round cross section such as some polyamides, polyesters, and glass; it may also be applied to a limited number of polyacrylics and regenerated cellulose-type fibers. Note 2—In subsequent sections of this test method, the term “ wool ” also signifies other animal fibers where applicable. Note 3—For fineness specifications of wool, wool top, mohair, mohair top, alpaca, and cashmere, refer to Specifications D3991 , D3992 , D2252 , and Test Method D2816 , respectively. 1.2 The OFDA reports average fiber diameter and standard deviation of fiber diameter in micrometer units ( μ m). The coefficient of variation of fiber diameter is reported as a percentage. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. ====== Significance And Use ====== This test method specifies sampling and testing procedures for the measurement of average fiber diameter and variation in diameter of animal fibers. This test method is considered satisfactory for acceptance testing of commercial shipments of wool and other animal fibers in raw and sliver form because current estimates of between-laboratory precision are acceptable. In cases of disagreement arising from differences in values reported by two or more laboratories when using this test method for acceptance testing, the statistical bias, if any, between the laboratories should be determined with each comparison being based on the testing of specimens randomly drawn from one sample of material of the type being evaluated. Test Method D2130 shall be used as a referee test method. This test method may be used for determining compliance with average fiber diameter and diameter variation to assign grades when determining conformance of shipments to material specifications given in Specifications D2252 , D3991 , and D3992 , and Test Method D2816 . The procedures for determining mean fiber diameter and standard deviation of fiber diameter provided in this test method and in IWTO Method 47-98 are in essential agreement.