政策法规现行有效美国危险品合规

§ 173.434 Activity-mass relationships for uranium and natural thorium.

效力	法规类型	发布日期	生效日期	发文机构
现行有效	部门规章	2026-08-07	2026-09-08	Code of Federal Regulations (CFR) - Transportation (Title 49)

发布08-07

生效09-08

摘要总结AI 辅助解读

该条款为美国联邦法规第49篇（运输）中关于铀和天然钍的活度-质量关系表。它提供了不同浓缩度（从贫铀到高浓铀）及天然钍的具体比活度数据，单位涵盖TBq/g、Ci/g等。这是危险品分类的核心技术依据，直接决定货物是否属于放射性物质及其类别（如I级白/II级黄/III级黄）。2026年8月7日发布，9月8日生效，相关从业者需确保申报单证中的活度计算与此表一致。

The table of activity-mass relationships for uranium and natural thorium are as follows:

Thorium and uranium enrichment 1 (Wt% 235 U present) Specific activity TBq/gram Grams/Tbq Ci/gram Grams/Ci 0.45 (depleted) 1.9 × 10 −8 5.4 × 10 7 5.0 × 10 −7 2.0 × 10 6 0.72 (natural) 2.6 × 10 −8 3.8 × 10 7 7.1 × 10 −7 1.4 × 10 6 1.0 2.8 × 10 −8 3.6 × 10 7 7.6 × 10 −7 1.3 × 10 6 1.5 3.7 × 10 −8 2.7 × 10 7 1.0 × 10 −6 1.0 × 10 6 5.0 1.0 × 10 −7 1.0 × 10 7 2.7 × 10 −6 3.7 × 10 5 10.0 1.8 × 10 −7 5.6 × 10 6 4.8 × 10 −6 2.1 × 10 5 20.0 3.7 × 10 −7 2.7 × 10 6 1.0 × 10 −5 1.0 × 10 5 35.0 7.4 × 10 −7 1.4 × 10 6 2.0 × 10 −5 5.0 × 10 4 50.0 9.3 × 10 −7 1.1 × 10 6 2.5 × 10 −5 4.0 × 10 4 90.0 2.1 × 10 −6 4.7 × 10 5 5.8 × 10 −5 1.7 × 10 4 93.0 2.6 × 10 −6 3.9 × 10 5 7.0 × 10 −5 1.4 × 10 4 95.0 3.4 × 10 −6 3.0 × 10 5 9.1 × 10 −5 1.1 × 10 4 Natural thorium 8.1 × 10 −9 1.2 × 10 8 2.2 × 10 −7 4.6 × 10 6 1 The figures for uranium include representative values for the activity of uranium-234 which is concentrated during the enrichment process. The activity for thorium includes the equilibrium concentration of thorium-228.

[Amdt. 173-244, 60 FR 50307, Sept. 28, 1995, as amended by 63 FR 52849, Oct. 1, 1998]