1.1 本规程涵盖了将成品短纤、长条（或顶部）或丝束分为批次的程序，以及对此类批次进行抽样测试的程序。 注1: 有关纱线的取样，请参阅规程 D2258 . 注2: 这种做法不同于BISFA 2. 通过消除外部和内部容器区域的单独采样，将层数从6层减少到5层，以及通过消除合成，在测试不取决于接收水分含量的性能时，获得该批次的单个实验室样品，对批次中的短纤维进行采样的规则。 1.2 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、健康和环境实践，并确定监管限制的适用性。 1.3 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 为容器或批次、托运或交付中材料的任何属性赋值涉及一个测量过程，该过程包括采样和测试程序。分配值的正确性取决于测试引起的可变性。即使通过精心制定的程序将测试引起的可变性降至最低，只有在采样程序避免系统偏差、将采样引起的变化降至最低并提供足够大小的实验室样品时，才可能正确且一致地估计特性的真值。 5.2 本规程可能不会给出在特殊情况下可能设计的最有效的采样计划，但它确实提供了一个通用程序，该程序以经济的采样量提供了令人满意的精度，并且不需要基于批次样本之间、实验室样本之间的变异量的先前知识进行详细的统计计算，以及试样之间。 5.3 平均结果中给定可变性所需的最小样本数通常通过以下方式获得:（1）最小化批次样本中的装运单元数，（2）从实验室样本中选取一个装运单元，以及（3）从选定的实验室样本装运单元中选取规定的样本。 （参见 7.3 和 7.4 .) 5.4 为了将大量材料的抽样成本降到最低，有必要就大量材料的报告平均值的所需方差达成一致: 5.4.1 估计因批次样本引起的方差、因实验室样本引起的方差和因试样引起的方差。 5.4.2 计算批次样本数量、每个批次样本的实验室样本数量和每个实验室样本的测试样本数量的几种组合的平均测试结果的总方差。 5.4.3 计算执行中考虑的每个采样方案的成本 5.4.2 . 5.4.4 选择（1）具有所需精度和（2）最经济的采样方案。

1.1 This practice covers a procedure for the division of shipments of manufactured staple fiber, sliver (or top) or tow into lots and the sampling of such lots for testing. Note 1: For sampling yarns, refer to Practice D2258 . Note 2: This practice differs from BISFA 2 rules for staple fibers in the lot sampling, by the elimination of separate sampling of outer versus inner container areas, in the reduction of number of strata from 6 to 5, and by the elimination of compositing to obtain a single laboratory sample for the lot when testing properties which do not depend on as-received moisture content. 1.2 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 Assigning a value to any property of the material in a container or in a lot, consignment, or delivery involves a measurement process that includes both sampling and testing procedures. The correctness of the value assigned depends upon the variability due to testing. Even when the variability due to testing is minimized by carefully developed procedures, correct and consistent estimates of the true value of the property are possible only when the sampling procedure avoids systematic bias, minimizes variations due to sampling, and provides a laboratory sample of adequate size. 5.2 This practice may not give the most efficient sampling plan that might be devised in special situations but it does present a general procedure that gives satisfactory precision with an economical amount of sampling and one which does not require elaborate statistical computation based on previous knowledge of the amount of variation between lot samples, between laboratory samples, and between test specimens. 5.3 The smallest number of specimens required for a given variability in the average result will usually be obtained by (1) minimizing the number of shipping units in the lot sample, (2) taking one of the shipping units in the laboratory sample, and (3) taking the prescribed specimen(s) from the selected laboratory sample shipping unit. (See 7.3 and 7.4 .) 5.4 To minimize the cost of sampling a lot of material, it is necessary to agree on the required variance for the reported average for a lot of material: 5.4.1 Estimate the variance due to lot samples, the variance due to laboratory samples, and the variance due to test specimens. 5.4.2 Calculate the total variance for the average test results for several combinations of the number of lot samples, the number of laboratory samples per lot sample, and the number of test specimens per laboratory sample. 5.4.3 Calculate the cost of performing each of the sampling schemes considered in 5.4.2 . 5.4.4 Select the sampling scheme that (1) has the required precision, and (2) is most economical to perform.