Register April 2010 No. 652
APPENDIX P
Quantities of Radioactive Materials Requiring Consideration of the
Need for a Contingency Plan for Responding to a Release
Radioactive Material1/ Release Fraction Quantity (GBq)
Quantity (Ci)
Actinium-228 0.001 148,000 4,000
Americium-241 0.001 74 2
Americium-242 0.001 74 2
Americium-243 0.001 74 2
Antimony-124 0.01 148,000 4,000
Antimony-126 0.01 222,000 6,000
Barium-133 0.01 370,000 10,000
Barium-140 0.01 1,110,000 30,000
Bismuth-207 0.01 185,000 5,000
Bismuth-210 0.01 22,200 600
Cadmium-109 0.01 37,000 1,000
Cadmium-113 0.01 2,960 80
Calcium-45 0.01 740,000 20,000
Californium-252 0.001 333 9 (20 mg)
Carbon-14 (Non-CO2) 0.01 1,850,000 50,000
Cerium-141 0.01 370,000 10,000
Cerium-144 0.01 11,100 300
Cesium-134 0.01 74,000 2,000
Cesium-137 0.01 111,000 3,000
Chlorine-36 0.5 3,700 100
Chromium-51 0.01 11,100,000 300,000
Cobalt-60 0.001 185,000 5,000
Copper-64 0.01 7,400,000 200,000
Curium-242 0.001 2,220 60
Curium-243 0.001 110 3
Curium-244 0.001 148 4
Curium-245 0.001 74 2
Europium-152 0.01 18,500 500
Europium-154 0.01 14,800 400
Europium-155 0.01 111,000 3,000
Gadolinium-153 0.01 185,000 5,000
Germanium-68 0.01 74,000 2,000
Gold-198 0.01 1,110,000 30,000
Hafnium-172 0.01 14,800 400
Hafnium-181 0.01 259,000 7,000
Holmium-166m 0.01 3,700 100
Hydrogen-3 0.5 740,000 20,000
Indium-114m 0.01 37,000 1,000
Iodine-125 0.5 370 10
Iodine-131 0.5 370 10
Iridium-192 0.001 1,480,000 40,000
Iron-55 0.01 1,480,000 40,000
Iron-59 0.01 259,000 7,000
Krypton-85 1.0 222,000,000 6,000,000
Lead-210 0.01 296 8
Manganese-56 0.01 2,220,000 60,000
Radioactive Material1/
Release Fraction Quantity (GBq)
Quantity (Ci)
Mercury-203 0.01 370,000 10,000
Molybdenum-99 0.01 1,110,000 30,000
Neptunium-237 0.001 74 2
Nickel-63 0.01 740,000 20,000
Niobium-94 0.01 11,100 300
Phosphorus-32 0.5 3,700 100
Phosphorus-33 0.5 37,000 1,000
Polonium-210 0.01 370 10
Potassium-42 0.01 333,000 9,000
Promethium-145 0.01 148,000 4,000
Promethium-147 0.01 148,000 4,000
Radium-226 0.001 3,700 100
