政策法规现行有效美国危险品合规

§ 173.453 Fissile materials—exceptions.

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

本条款规定了美国运输部（DOT）关于易裂变材料（Fissile Materials）的豁免情形。若货物满足(a)至(f)款中任一条件（如低浓度铀、特定质量比的混合材料等），可豁免§173.457和§173.459关于临界安全控制及包装的具体要求，但仍须遵守其他危险品通用规定。该规则旨在简化低风险核材料的物流合规流程，明确界定“例外”边界，避免过度监管。

Fissile materials meeting the requirements of at least one of the paragraphs (a) through (f) of this section are excepted from the requirements of this subpart for fissile materials, including the requirements of §§ 173.457 and 173.459, but are subject to all other requirements of this subpart, except as noted.

(a) An individual package containing 2 grams or less of fissile material.
(b) An individual or bulk packaging containing 15 grams or less of fissile material provided the package has at least 200 grams of solid nonfissile material for every gram of fissile material. Lead, beryllium, graphite, and hydrogenous material enriched in deuterium may be present in the package but must not be included in determining the required mass for solid nonfissile material.
(c) Low concentrations of solid fissile material commingled with solid nonfissile material, provide that:

- (1) There is at least 2000 grams of nonfissile material for every gram of fissile material, and

- (2) There is no more than 180 grams of fissile material distributed within 360 kg of contiguous nonfissile material. Lead, beryllium, graphite, and hydrogenous material enriched in deuterium may be present in the package but must not be included in determining the required mass of solid nonfissile material.

(d) Uranium enriched in uranium-235 to a maximum of 1 percent by weight, and with total plutonium and uranium-233 content of up to 1 percent of the mass of uranium-235, provided that the mass of any beryllium, graphite, and hydrogenous material enriched in deuterium constitute less than 5 percent of the uranium mass.
(e) Liquid solutions of uranyl nitrate enriched in uranium-235 to a maximum of 2 percent by mass, with a total plutonium and uranium-233 content not exceeding 0.002 percent of the mass of uranium, and with a minimum nitrogen to uranium atomic ratio (N/U) of 2. The material must be contained in at least a DOT Type A package.
(f) Packages containing, individually, a total plutonium mass of not more than 1000 grams, of which not more than 20 percent by mass may consist of plutonium-239, plutonium-241, or any combination of these radionuclides.

[69 FR 3692, Jan. 26, 2004]