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The NRC is shutdown due to the lapse in appropriations. Exempted activities to maintain critical health and safety activities and progress on critical activities, including activities outlined in Executive Order 14300, as described in the OMB Approved NRC Lapse Plan will continue.

Appendix M to Part 110—Categorization of Nuclear Material

[From IAEA INFCIRC/225/Revision 5]

Material	Form	Category I	Category II	Category III³
1. Plutonium¹	Unirradiated²	2 kg or more	Less than 2 kg but more than 500 g.	500 g or less but more than 15 g.
2. Uranium-235 (²³⁵U).	Unirradiated:²
	—Uranium enriched to 20 percent ²³⁵U or more.	5 kg or more	Less than 5 kg but more than 1 kg.	1 kg or less but more than 15 g.
	—Uranium enriched to 10 percent ²³⁵U but less than 20 percent ²³⁵U.		10 kg or more	Less than 10 kg but more than 1 kg.
	—Uranium enriched above natural, but less than 10 percent ²³⁵U.			10 kg or more.
3. Uranium-233 (²³³U).	Unirradiated²	2 kg or more	Less than 2 kg but more than 500 g.	500 g or less but more than 15 g.
4. Irradiated Fuel (The categorization of irradiated fuel in the table is based on international transport considerations. The State may assign a different category for domestic use, storage and transport taking all relevant factors into account).			Depleted or natural uranium, thorium or low enriched fuel (less than 10 percent fissile content)⁴ ⁵

¹ All plutonium except that with isotopic concentration exceeding 80 percent in plutonium-238.

² Material not irradiated in a reactor or material irradiated in a reactor but with a radiation level equal to or less than 1 Gy/h (100 rad/h) at 1 m unshielded.

³ Quantities not falling in Category III and natural uranium, depleted uranium and thorium should be protected at least in accordance with prudent management practice.

⁴ Although this level of protection is recommended, it would be open to States, upon evaluation of the specific circumstances, to assign a different category of physical protection.

⁵ Other fuel which by virtue of its original fissile material content is classified as Category I or II before irradiation may be reduced one category level while the radiation level from the fuel exceeds 1 Gy/h (100 rad/h) at one meter unshielded.

(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; 79 FR 39299, Jul. 10, 2014]

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