1.1 本试验方法包括通过光度计测量沉淀硫酸钡的浊度来测定水中或滤液中的可溶性硫酸盐离子。还给出了该试验方法的光度计标准化方法。 1.2 在混合和随后的压滤过程中，可通过用水浸出的方式去除粘土或粘土水泥浆中的可溶性硫酸盐离子。去除所有的硫酸盐离子需要大量的洗涤；因此，该试验方法应被视为控制试验，而不是SO的定量分析 4. 离子。 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。

1.1 This test method covers the determination of soluble sulfate ions present in water or a filtrate by means of a photometer measuring the turbidity of precipitated barium sulfate. A method of standardizing the photometer for this test method is also given. 1.2 Soluble sulfate ions may be removed from clays or clay-water slurries by leaching with water during mixing and subsequent filter pressing. To remove all the sulfate ions would require an impractical number of washings; therefore, this test method should be considered a control test and not a quantitative analysis for SO 4 ions. 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.