1.1 本试验方法包括在30℃下通过硫酸钾饱和溶液测定大气中煤的平衡水分 °C。 注1: 有关此测试方法所基于的实验工作的信息，请参阅 ( 1- 5. ) . 2. 1.2 单位- 以国际单位制或非国际单位制表示的数值应单独视为标准值。每个系统中规定的值不一定是精确的等价物；因此，为确保符合本标准，每个系统应独立使用，且两个系统的值不得组合。 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、健康和环境实践，并确定监管限制的适用性。 1.4 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====== 3.1 本试验方法提供了一种估算潮湿且表面可见水分的煤炭或可能失去部分水分的煤炭固有水分的方法。它可用于估算湿煤的表面或外来水分，此类水分是通过试验方法确定的总水分之间的差值 D3302 和平衡水分。 3.2 当按照分类收集样本时 D388页 ，平衡水分被认为等于煤层水分，但一些低秩煤的平衡水分值低于煤层水分。 3.3 通过该试验方法获得的结果对许多影响很敏感，因此，原始（未修正）平衡水分数据本身的价值可能有限。当处理低秩煤时，这种测试方法产生的结果需要进行关键评估。 建议按照 附录X1 在需要更可靠地估计低煤阶煤的固有水分或煤层水分的情况下，使用前对结果进行校正。附录还提供了适用于所有等级煤炭的有用质量保证信息。

1.1 This test method covers determination of the equilibrium moisture of coal in an atmosphere over a saturated solution of potassium sulfate at 30 °C. Note 1: For information concerning the experimental work on which this test method is based, see ( 1- 5 ) . 2 1.2 Units— The values stated in either SI units or non-SI units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined. 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.4 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 ====== 3.1 This test method affords a means of estimating the inherent moisture of either coal that is wet and shows visible surface moisture or coal that may have lost some moisture. It may be used for estimating the surface, or extraneous moisture of wet coal, such moisture being the difference between the total moisture as determined by Test Method D3302 and the equilibrium moisture. 3.2 When samples are collected in conformity with Classification D388 , the equilibrium moisture is considered to be equal to bed moisture with the exception of some low rank coals that yield equilibrium moisture values below bed moisture. 3.3 The results obtained by this test method are sensitive to many influences, and therefore, raw (uncorrected) equilibrium moisture data may be of limited value in and of themselves. When working with low rank coals, the results yielded by this test method require critical assessments. It is recommended that the procedure outlined in the Appendix X1 be applied, and the results corrected before use in situations where a more reliable estimation inherent or bed moisture for low rank coals is required. The Appendix also provides useful quality assurance information which is applicable to coals of all ranks.