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Atomic Energy Act of 1954, secs. 11, 53, 63, 65, 81, 103, 104, 161, 170H, 182, 186, 223, 234, 274, 1701 (42 U.S.C. 2014, 2073, 2093, 2095, 2111, 2133, 2134, 2201, 2210h, 2232, 2236, 2273, 2282, 2021, 2297f); Energy Reorganization Act of 1974, secs. 201, 202 (42 U.S.C. 5841, 5842); Low-Level Radioactive Waste Policy Amendments Act of 1985, sec. 2 (42 U.S.C. 2021b); 44 U.S.C. 3504 note.
56 FR 23391, May 21, 1991, unless otherwise noted.
56 FR 23396, May 21, 1991, unless otherwise noted.
56 FR 23396, May 21, 1991, unless otherwise noted.
56 FR 23398, May 21, 1991, unless otherwise noted.
62 FR 39088, July 21, 1997, unless otherwise noted.
56 FR 23398, May 21, 1991, unless otherwise noted.
56 FR 23398, May 21, 1991, unless otherwise noted.
56 FR 23400, May 21, 1991, unless otherwise noted.
56 FR 23401, May 21, 1991, unless otherwise noted.
56 FR 23401, May 21, 1991, unless otherwise noted.
56 FR 23403, May 21, 1991, unless otherwise noted.
56 FR 23404, May 21, 1991, unless otherwise noted.
56 FR 23406, May 21, 1991, unless otherwise noted.
56 FR 23408, May 21, 1991, unless otherwise noted.
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The Terabecquerel (TBq) values are the regulatory standard. The curie (Ci) values specified are obtained by converting from the TBq value. The curie values are provided for practical usefulness only and are rounded after conversion.
| Radioactive material | Category 1 (TBq) |
Category 1 (Ci) |
Category 2 (TBq) |
Category 2 (Ci) |
|---|---|---|---|---|
| Actinium-227 | 20 | 540 | 0.2 | 5.4 |
| Americium-241 | 60 | 1,600 | 0.6 | 16 |
| Americium-241/Be | 60 | 1,600 | 0.6 | 16 |
| Californium-252 | 20 | 540 | 0.2 | 5.4 |
| Cobalt-60 | 30 | 810 | 0.3 | 8.1 |
| Curium-244 | 50 | 1,400 | 0.5 | 14 |
| Cesium-137 | 100 | 2,700 | 1 | 27 |
| Gadolinium-153 | 1,000 | 27,000 | 10 | 270 |
| Iridium-192 | 80 | 2,200 | 0.8 | 22 |
| Plutonium-238 | 60 | 1,600 | 0.6 | 16 |
| Plutonium-239/Be | 60 | 1,600 | 0.6 | 16 |
| Polonium-210 | 60 | 1,600 | 0.6 | 16 |
| Promethium-147 | 40,000 | 1,100,000 | 400 | 11,000 |
| Radium-226 | 40 | 1,100 | 0.4 | 11 |
| Selenium-75 | 200 | 5,400 | 2 | 54 |
| Strontium-90 | 1,000 | 27,000 | 10 | 270 |
| Thorium-228 | 20 | 540 | 0.2 | 5.4 |
| Thorium-229 | 20 | 540 | 0.2 | 5.4 |
| Thulium-170 | 20,000 | 540,000 | 200 | 5,400 |
| Ytterbium-169 | 300 | 8,100 | 3 | 81 |
[71 FR 65708, Nov. 8, 2006]