1.1 本试验方法包括在涂覆粘合剂背涂层前后测量机织、针织和簇绒纱线地板覆盖物的单位面积质量。 1.2 本试验方法包括三种确定单位面积质量的技术（如适用）: 1.2.1 部分 7. ，用于确定单位面积的总质量，适用于涂层和未涂层（未加工）桩地板覆盖物。 1.2.2 部分 8. ，用于确定单位面积的组件质量，仅适用于未涂层（未加工）的绒线地板覆盖物。 1.2.3 部分 9 ，用于确定单位面积的绒线质量，仅适用于后涂层或成品绒线地板覆盖物。 1.3 测定绒线地板覆盖物单位面积的质量之前包含在试验方法中 D418页 . 为方便用户，小组委员会D13.21对试验方法进行了细分 D418页 分为不同的标准，本试验方法就是其中之一。 1.4 以英寸-磅为单位的数值应视为标准值。括号中给出的值是到国际单位制的数学转换，仅供参考（中所示除外） 1.4.1 )不被视为标准。 1.4.1 以下截面采用国际单位制测量:表1，截面 9.8.4.2 , 9.8.6.3 到 9.8.6.10 , A2.1 , A2.2 和 A2.3 . 1.5 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。具体预防说明见 9.5 . 1.6 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====== 4.1 测定绒线地板覆盖物的单位面积质量有助于控制绒线地板覆盖物制造过程中的质量和成本。外观和性能都可能受到单位面积质量变化的影响。 4.2 如果使用本测试方法进行商业装运验收测试时，由于报告测试结果的差异而产生争议，买方和供应商应进行比较测试，以确定其实验室之间是否存在统计偏差。建议为调查偏差提供称职的统计协助。作为最低要求，双方应尽可能均匀地从大量相关类型的材料中选取一组试样。然后，应将试样随机分配到每个实验室进行测试。两个实验室的平均结果应使用学生的 t -测试未配对数据和双方在测试前选择的可接受概率水平。如果发现偏差，必须找到并纠正其原因，或者买方和供应商必须同意在考虑已知偏差的情况下解释未来的测试结果。

1.1 This test method covers the measurement of mass per unit area of machine-made woven, knitted, and tufted pile yarn floor covering both before and after an adhesive-back coating application. 1.2 This test method encompasses three techniques for determination of mass per unit area as applicable: 1.2.1 Section 7 , for determining total mass per unit area, applies to both coated and uncoated (unfinished) pile floor coverings. 1.2.2 Section 8 , for determining component mass per unit area, applies only to uncoated (unfinished) pile yarn floor coverings. 1.2.3 Section 9 , for determining pile yarn mass per unit area, applies only to back-coated, or finished, pile yarn floor coverings. 1.3 Determination of mass per unit area of pile yarn floor coverings was previously contained within Test Methods D418 . For user convenience, Subcommittee D13.21 subdivided Test Methods D418 into separate standards, of which this test method is one. 1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only (except where shown in 1.4.1 ) and are not considered standard. 1.4.1 The following sections are measured in SI units: Table 1, sections 9.8.4.2 , 9.8.6.3 to 9.8.6.10 , A2.1 , A2.2 , and A2.3 . 1.5 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. Specific precautionary statements are given in 9.5 . 1.6 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 ====== 4.1 The determination of the mass per unit area of pile yarn floor covering is useful in quality and cost control during the manufacture of pile floor covering. Both appearance and performance may be affected by changes in mass per unit area. 4.2 In case of a dispute arising from differences in reported test results when using this test method for acceptance testing of commercial shipments, the purchaser and supplier should conduct comparison testing to determine if there is a statistical bias between their laboratories. Competent statistical assistance is recommended for the investigation of bias. As a minimum the two parties should take a group of test specimens that are as homogeneous as possible and that are from a lot of material of the type in question. The test specimens should then be randomly assigned to each laboratory for testing. The average results from the two laboratories should be compared using Student's t -test for unpaired data and an acceptable probability level chosen by the two parties prior to testing. If a bias is found, either its cause must be found and corrected or the purchaser and supplier must agree to interpret future test results with consideration to the known bias.