Code of Federal Regulations > Title 10 > Chapter I > Part 110 > Subpart K > Appendix Appendix M - Appendix M to Part 110

Regulations last checked for updates: Nov 22, 2024

Title 10 - Energy last revised: Nov 19, 2024

Appendix Appendix M - Appendix M to Part 110—Categorization of Nuclear Material d

[From IAEA INFCIRC/225, Rev. 1]

Material	Form	Category
Material	Form	I	II	III ^e
1. Plutonium ^a	Unirradiated ^b	2 kg or more	Less than 2 kg but more than 500 g	500 g or less.
2. Uranium-235 ^c	Unirradiated: ^b
	Uranium enriched to 20 pct U ²³⁵ or more	5 kg or more	Less than 5 kg but more than 1 kg	1 kg or less.
	Uranium enriched to 10 pct U ²³⁵ but less than 20 pct		10 kg or more	Less than 10 kg.
	Uranium enriched above natural, but less than 10 pct U ²³⁵			10 kg or more.
3. Uranium-233	Unirradiated ^b	2 kg or more	Less than 2 kg but more than 500 g	500 g or less.

^a All plutonium except that with isotopic concentration exceeding 80 pct in plutonium-238.

^b Material not irradiated in a reactor or material irradiated in a reactor but with a radiation level equal to or less than 100 rd/h at 1 m unshielded.

^c Natural uranium, depleted uranium, thorium and quantities of uranium enriched to less than 10% not falling into Category III should be protected in accordance with prudent management practice.

^d Irradiated fuel should be protected as category I, II, or III nuclear material depending on the category of the fresh fuel. However, fuel which by virtue of its original fissile material content is included as category I or II before irradiation should only be reduced one category level, while the radiation level from the fuel exceeds 100 rd/h at 1 m unshielded.

^e Physical security determinations will not be required for 15 g or less of plutonium, uranium-233 or high-enriched uranium, or for 1 kg or less of uranium with an enrichment between 10 and 20 pct in uranium-235.

(Sec. 161, as amended, Pub. L. 83-703, 68 Stat. 948 (42 U.S.C. 2201); sec. 201, as amended, Pub. L. 93-438, 88 Stat. 1243 (42 U.S.C. 5841)) [43 FR 21641, May 19, 1978. Redesignated and amended at 49 FR 47204, Dec. 3, 1984. Further redesignated at 55 FR 30450, July 26, 1990; 58 FR 13005, Mar. 9, 1993; 61 FR 35603, July 8, 1996]

authority: Atomic Energy Act of 1954, secs. 11, 51, 53, 54, 57, 62, 63, 64, 65, 81, 82, 103, 104, 109, 111, 121, 122, 123, 124, 126, 127, 128, 129, 133, 134, 161, 170H, 181, 182, 183, 184, 186, 187, 189, 223, 234 (42 U.S.C. 2014,2071,2073,2074,2077,2092,2093,2094,2095,2111,2112,2133,2134,2139,2141,2151,2152,2153,2154,2155,2156,2157,2158,2160c,2160d,2201,2210h,2231,2232,2233,2234,2236,2237,2239,2273,2282; Energy Reorganization Act of 1974, sec. 201 (42 U.S.C. 5841); Administrative Procedure Act (5 U.S.C. 552,553; 42 U.S.C. 2139a,2155a; 44 U.S.C. 3504 note

source: 43 FR 21641, May 19, 1978, unless otherwise noted.