1.1 本试验方法涵盖了一种定量试验方法，适用于测定六氟化铀（UF）中铀同位素的质量百分比 6. )样品。所述方法适用于 235 U介于0.1和10之间 大量 %, 和 234 U和 236 U在0.0001和0.1质量之间 %. 1.2 本试验方法用于通过带有多收集器的气体质谱仪进行实验室分析。 1.3 本标准是对试验方法的补充 C761 ，通过提供使用多采集器的光谱仪的方法，使用单采集器的气体质谱仪的双标准方法。 1.4 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。 1.5 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 用于生产核反应堆燃料的六氟化铀必须符合某些同位素组成标准。本试验方法可用于帮助确定样品材料是否符合规范中所述的标准 C787 和 C996 .

1.1 This test method covers a quantitative test method applicable to determining the mass percent of uranium isotopes in uranium hexafluoride (UF 6 ) samples. This method as described is for concentrations of 235 U between 0.1 and 10 mass %, and 234 U and 236 U between 0.0001 and 0.1 mass %. 1.2 This test method is for laboratory analysis by a gas mass spectrometer with a multi-collector. 1.3 This standard complements Test Methods C761 , the double-standard method for gas mass spectrometers using a single collector, by providing a method for spectrometers using a multi-collector. 1.4 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. 1.5 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 Uranium hexafluoride used to produce nuclear-reactor fuel must meet certain criteria for its isotopic composition. This test method may be used to help determine if sample materials meet the criteria described in Specifications C787 and C996 .