1.1 本试验方法包括测定水蒸气通过柔性屏障材料的传输速率的程序。该方法适用于由单层或多层合成或天然聚合物和箔组成的片材和薄膜，包括涂层材料。它提供了水蒸气透过率（WVTR）的测定。 1.2 以国际单位制表示的数值应视为标准。本标准中不包括其他计量单位。 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）。 本标准的使用者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》中确立的国际公认的标准化原则制定的。 ====意义和用途====== 5.1 本试验方法的目的是获得塑料薄膜和片材的WVTR的可靠值。 5.2 WVTR是包装材料的一项重要性能，可直接关系到包装产品的保质期和稳定性。 5.3 如果买方和卖方就取样程序、标准化程序、试验条件和验收标准达成一致，则该试验方法的数据适合作为试验的参考方法。

1.1 This test method covers a procedure for determining the rate of water vapor transmission through flexible barrier materials. The method is applicable to sheets and films consisting of single or multilayer synthetic or natural polymers and foils, including coated materials. It provides for the determination of water vapor transmission rate (WVTR). 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 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 ====== 5.1 The purpose of this test method is to obtain reliable values for the WVTR of plastic film and sheeting. 5.2 WVTR is an important property of packaging materials and can be directly related to shelf life and packaged product stability. 5.3 Data from this test method is suitable as a referee method of testing, provided that the purchaser and seller have agreed on sampling procedures, standardization procedures, test conditions, and acceptance criteria.