49 CFR 173.436: Exempt material and consignment radionuclide limits
Last reviewed: October 14, 2026
This section gives a table of exempt material activity concentrations and exempt consignment activity limits for radionuclides. Each radionuclide has values in Bq/g and Ci/g for exempt material, and in Bq and Ci for an exempt consignment. Notes below the table explain parent nuclides, progeny, and uranium compound forms.
What it says
The section sets out a table of exempt material activity concentrations and exempt consignment activity limits for radionuclides.
“The Table of Exempt material activity concentrations and exempt consignment activity limits for radionuclides is as follows:”
Note (b) says the parent nuclides marked (b) are listed with their progeny included in secular equilibrium.
“Parent nuclides and their progeny included in secular equilibrium are listed as follows:”
Notes (d) and (e) say the values for certain uranium lung absorption types apply only to specific uranium compounds, in both normal and accident conditions of transport.
“These values apply only to compounds of uranium that take the chemical form of UF6, UO2 F2 and UO2 (NO3)2 in both normal and accident conditions of transport.”
Note (f) says the slow lung absorption values apply to all uranium compounds other than those specified in notes (d) and (e) of this table.
“These values apply to all compounds of uranium other than those specified in notes (d) and (e) of this table.”
Note (g) says the values for uranium enriched to 20% or less apply to unirradiated uranium only.
“These values apply to unirradiated uranium only.”
Common questions
What does 49 CFR 173.436 contain?
It contains a table of exempt material activity concentrations and exempt consignment activity limits for radionuclides.
“The Table of Exempt material activity concentrations and exempt consignment activity limits for radionuclides is as follows:”
Do the uranium enriched to 20% or less values apply to irradiated uranium?
No. The note says those values apply to unirradiated uranium only.
“These values apply to unirradiated uranium only.”
Which uranium compounds do the slow lung absorption values cover?
They cover all uranium compounds other than those specified in notes (d) and (e) of the table.
“These values apply to all compounds of uranium other than those specified in notes (d) and (e) of this table.”
The text of 49 CFR 173.436
Electronic Code of Federal Regulations (eCFR), current as of April 16, 2026 · Read it on eCFR
Exempt material activity concentrations and exempt consignment activity limits for radionuclides
The Table of Exempt material activity concentrations and exempt consignment activity limits for radionuclides is as follows:
Symbol ofradionuclide Element and atomic number Activity concentration for exempt material(Bq/g) Activity concentration for exempt material(Ci/g) Activity limit for exempt consignment(Bq) Activity limit for exempt consignment(Ci) Ac-225 Actinium (89) 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 Ac-227 1.0 × 10−1 2.7 × 10−12 1.0 × 103 2.7 × 10−8 Ac-228 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Ag-105 Silver (47) 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Ag-108m (b) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Ag-110m 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Ag-111 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Al-26 Aluminum (13) 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Am-241 Americium (95) 1.0 2.7 × 10−11 1.0 × 104 2.7 × 10−7 Am-242m (b) 1.0 2.7 × 10−11 1.0 × 104 2.7 × 10−7 Am-243 (b) 1.0 2.7 × 10−11 1.0 × 103 2.7 × 10−8 Ar-37 Argon (18) 1.0 × 106 2.7 ×
10−5 1.0 × 108 2.7 × 10−3 Ar-39 1.0 × 107 2.7 × 10−4 1.0 × 104 2.7 × 10−7 Ar-41 1.0 × 102 2.7 × 10−9 1.0 × 109 2.7 × 10−2 As-72 Arsenic (33) 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 As-73 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 As-74 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 As-76 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 As-77 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 At-211 Astatine (85) 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Au-193 Gold (79) 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Au-194 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Au-195 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Au-198 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Au-199 1.0 × 102 2.7 × 10
−9 1.0 × 106 2.7 × 10−5 Ba-131 Barium (56) 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Ba-133 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Ba-133m 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Ba-140 (b) 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Be-7 Beryllium (4) 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Be-10 1.0 × 104 2.7 × 10−7 1.0 × 106 2.7 × 10−5 Bi-205 Bismuth (83) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Bi-206 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Bi-207 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Bi-210 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Bi-210m 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Bi-212 (b) 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Bk-247 Berkelium (
97) 1.0 2.7 × 10−11 1.0 × 104 2.7 × 10−7 Bk-249 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Br-76 Bromine (35) 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Br-77 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Br-82 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 C-11 Carbon (6) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 C-14 1.0 × 104 2.7 × 10−7 1.0 × 107 2.7 × 10−4 Ca-41 Calcium (20) 1.0 × 105 2.7 × 10−6 1.0 × 107 2.7 × 10−4 Ca-45 1.0 × 104 2.7 × 10−7 1.0 × 107 2.7 × 10−4 Ca-47 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Cd-109 Cadmium (48) 1.0 × 104 2.7 × 10−7 1.0 × 106 2.7 × 10−5 Cd-113m 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Cd-115 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5
Cd-115m 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Ce-139 Cerium (58) 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Ce-141 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Ce-143 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Ce-144 (b) 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 Cf-248 Californium (98) 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 Cf-249 1.0 2.7 × 10−11 1.0 × 103 2.7 × 10−8 Cf-250 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 Cf-251 1.0 2.7 × 10−11 1.0 × 103 2.7 × 10−8 Cf-252 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 Cf-253 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 Cf-254 1.0 2.7 × 10−11 1.0 × 103 2.7 × 10−8 Cl-36 Chlorine (17) 1.0 × 104 2.7 × 10−7 1.0 × 106 2.7 × 10
−5 Cl-38 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Cm-240 Curium (96) 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 Cm-241 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Cm-242 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 Cm-243 1.0 2.7 × 10−11 1.0 × 104 2.7 × 10−7 Cm-244 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 Cm-245 1.0 2.7 × 10−11 1.0 × 103 2.7 × 10−8 Cm-246 1.0 2.7 × 10−11 1.0 × 103 2.7 × 10−8 Cm-247 1.0 2.7 × 10−11 1.0 × 104 2.7 × 10−7 Cm-248 1.0 2.7 × 10−11 1.0 × 103 2.7 × 10−8 Co-55 Cobalt (27) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Co-56 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Co-57 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Co-58 1.0 ×
101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Co-58m 1.0 × 104 2.7 × 10−7 1.0 × 107 2.7 × 10−4 Co-60 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Cr-51 Chromium (24) 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Cs-129 Cesium (55) 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 Cs-131 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Cs-132 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Cs-134 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 Cs-134m 1.0 × 103 2.7 × 10−8 1.0 × 105 2.7 × 10−6 Cs-135 1.0 × 104 2.7 × 10−7 1.0 × 107 2.7 × 10−4 Cs-136 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Cs-137 (b) 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 Cu-64 Copper (29) 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Cu-67 1.0
× 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Dy-159 Dysprosium (66) 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Dy-165 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Dy-166 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Er-169 Erbium (68) 1.0 × 104 2.7 × 10−7 1.0 × 107 2.7 × 10−4 Er-171 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Eu-147 Europium (63) 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Eu-148 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Eu-149 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Eu-150 (short lived) 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Eu-150 (long lived) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Eu-152 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Eu-152m 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7
× 10−5 Eu-154 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Eu-155 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Eu-156 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 F-18 Fluorine (9) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Fe-52 Iron (26) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Fe-55 1.0 × 104 2.7 × 10−7 1.0 × 106 2.7 × 10−5 Fe-59 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Fe-60 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 Ga-67 Gallium (31) 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Ga-68 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Ga-72 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Gd-146 Gadolinium (64) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Gd-148 1.0 × 101 2.7 × 10−10 1
.0 × 104 2.7 × 10−7 Gd-153 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Gd-159 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Ge-68 Germanium (32) 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Ge-71 1.0 × 104 2.7 × 10−7 1.0 × 108 2.7 × 10−3 Ge-77 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Hf-172 Hafnium (72) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Hf-175 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Hf-181 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Hf-182 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Hg-194 Mercury (80) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Hg-195m 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Hg-197 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Hg-197m 1.0 ×
102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Hg-203 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 Ho-166 Holmium (67) 1.0 × 103 2.7 × 10−8 1.0 × 105 2.7 × 10−6 Ho-166m 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 I-123 Iodine (53) 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 I-124 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 I-125 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 I-126 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 I-129 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 I-131 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 I-132 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 I-133 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 I-134 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 I-135 1.0 × 101 2.
7 × 10−10 1.0 × 106 2.7 × 10−5 In-111 Indium (49) 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 In-113m 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 In-114m 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 In-115m 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Ir-189 Iridium (77) 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Ir-190 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Ir-192 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 Ir-194 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 K-40 Potassium (19) 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 K-42 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 K-43 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Kr-79 Krypton (36) 1.0 × 10 3 2.7 × 10−8 1.0 × 10 5 2.7 × 10−6 Kr-
81 Krypton (36) 1.0 × 104 2.7 × 10−7 1.0 × 107 2.7 × 10−4 Kr-85 1.0 × 105 2.7 × 10−6 1.0 × 104 2.7 × 10−7 Kr-85m 1.0 × 103 2.7 × 10−8 1.0 × 1010 2.7 × 10−1 Kr-87 1.0 × 102 2.7 × 10−9 1.0 × 109 2.7 × 10−2 La-137 Lanthanum (57) 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 La-140 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Lu-172 Lutetium (71) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Lu-173 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Lu-174 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Lu-174m 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Lu-177 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Mg-28 Magnesium (12) 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Mn-52 Manganese (25) 1.0 × 101 2.7 × 10−10 1
.0 × 105 2.7 × 10−6 Mn-53 1.0 × 104 2.7 × 10−7 1.0 × 109 2.7 × 10−2 Mn-54 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Mn-56 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Mo-93 Molybdenum (42) 1.0 × 103 2.7 × 10−8 1.0 × 108 2.7 × 10−3 Mo-99 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 N-13 Nitrogen (7) 1.0 × 102 2.7 × 10−9 1.0 × 109 2.7 × 10−2 Na-22 Sodium (11) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Na-24 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Nb-93m Niobium (41) 1.0 × 104 2.7 × 10−7 1.0 × 107 2.7 × 10−4 Nb-94 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Nb-95 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Nb-97 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Nd-147 Neodymium (60)
1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Nd-149 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Ni-59 Nickel (28) 1.0 × 104 2.7 × 10−7 1.0 × 108 2.7 × 10−3 Ni-63 1.0 × 105 2.7 × 10−6 1.0 × 108 2.7 × 10−3 Ni-65 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Np-235 Neptunium (93) 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Np-236 (short-lived) 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Np-236 (long-lived) 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 Np-237 (b) 1.0 2.7 × 10−11 1.0 × 103 2.7 × 10−8 Np-239 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Os-185 Osmium (76) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Os-191 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Os-191m 1.0 × 103 2.7 × 10−8 1.0 × 107 2
.7 × 10−4 Os-193 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Os-194 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 P-32 Phosphorus (15) 1.0 × 103 2.7 × 10−8 1.0 × 105 2.7 × 10−6 P-33 1.0 × 105 2.7 × 10−6 1.0 × 108 2.7 × 10−3 Pa-230 Protactinium (91) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Pa-231 1.0 2.7 × 10−11 1.0 × 103 2.7 × 10−8 Pa-233 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Pb-201 Lead (82) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Pb-202 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Pb-203 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Pb-205 1.0 × 104 2.7 × 10−7 1.0 × 107 2.7 × 10−4 Pb-210 (b) 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 Pb-212 (b) 1.0 × 101 2.7 × 10−10 1.
0 × 105 2.7 × 10−6 Pd-103 Palladium (46) 1.0 × 103 2.7 × 10−8 1.0 × 108 2.7 × 10−3 Pd-107 1.0 × 105 2.7 × 10−6 1.0 × 108 2.7 × 10−3 Pd-109 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Pm-143 Promethium (61) 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Pm-144 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Pm-145 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Pm-147 1.0 × 104 2.7 × 10−7 1.0 × 107 2.7 × 10−4 Pm-148m 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Pm-149 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Pm-151 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Po-210 Polonium (84) 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 Pr-142 Praseodymium (59) 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 Pr-143
1.0 × 104 2.7 × 10−7 1.0 × 106 2.7 × 10−5 Pt-188 Platinum (78) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Pt-191 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Pt-193 1.0 × 104 2.7 × 10−7 1.0 × 107 2.7 × 10−4 Pt-193m 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Pt-195m 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Pt-197 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Pt-197m 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Pu-236 Plutonium (94) 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 Pu-237 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Pu-238 1.0 2.7 × 10−11 1.0 × 104 2.7 × 10−7 Pu-239 1.0 2.7 × 10−11 1.0 × 104 2.7 × 10−7 Pu-240 1.0 2.7 × 10−11 1.0 × 103 2.7 × 10−8 Pu-241 1.0 × 102 2.7 ×
10−9 1.0 × 105 2.7 × 10−6 Pu-242 1.0 2.7 × 10−11 1.0 × 104 2.7 × 10−7 Pu-244 1.0 2.7 × 10−11 1.0 × 104 2.7 × 10−7 Ra-223 (b) Radium (88) 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 Ra-224 (b) 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Ra-225 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 Ra-226 (b) 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 Ra-228 (b) 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Rb-81 Rubidium (37) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Rb-83 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Rb-84 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Rb-86 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 Rb-87 1.0 × 104 2.7 × 10−7 1.0 × 107 2.7 × 10−4 Rb(nat) 1.0 × 104 2.7
× 10−7 1.0 × 107 2.7 × 10−4 Re-184 Rhenium (75) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Re-184m 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Re-186 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Re-187 1.0 × 106 2.7 × 10−5 1.0 × 109 2.7 × 10−2 Re-188 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 Re-189 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Re(nat) 1.0 × 106 2.7 × 10−5 1.0 × 109 2.7 × 10−2 Rh-99 Rhodium (45) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Rh-101 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Rh-102 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Rh-102m 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Rh-103m 1.0 × 104 2.7 × 10−7 1.0 × 108 2.7 × 10−3 Rh-105 1.0 × 102 2.7 × 10
−9 1.0 × 107 2.7 × 10−4 Rn-222 (b) Radon (86) 1.0 × 101 2.7 × 10−10 1.0 × 108 2.7 × 10−3 Ru-97 Ruthenium (44) 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Ru-103 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Ru-105 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Ru-106 (b) 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 S-35 Sulphur (16) 1.0 × 105 2.7 × 10−6 1.0 × 108 2.7 × 10−3 Sb-122 Antimony (51) 1.0 × 102 2.7 × 10−9 1.0 × 104 2.7 × 10−7 Sb-124 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Sb-125 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Sb-126 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Sc-44 Scandium (21) 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Sc-46 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 ×
10−5 Sc-47 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Sc-48 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Se-75 Selenium (34) 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Se-79 1.0 × 104 2.7 × 10−7 1.0 × 107 2.7 × 10−4 Si-31 Silicon (14) 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Si-32 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Sm-145 Samarium (62) 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Sm-147 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 Sm-151 1.0 × 104 2.7 × 10−7 1.0 × 108 2.7 × 10−3 Sm-153 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Sn-113 Tin (50) 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Sn-117m 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Sn-119m 1.0 × 103 2.7 × 10−8 1.0 ×
107 2.7 × 10−4 Sn-121m 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Sn-123 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Sn-125 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 Sn-126 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Sr-82 Strontium (38) 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Sr-85 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Sr-85m 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Sr-87m 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Sr-89 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Sr-90 (b) 1.0 × 102 2.7 × 10−9 1.0 × 104 2.7 × 10−7 Sr-91 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Sr-92 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 T(H-3) Tritium (1) 1.0 × 106 2.7 × 10−5 1.0 ×
109 2.7 × 10−2 Ta-178 (long-lived) Tantalum (73) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Ta-179 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Ta-182 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 Tb-157 Terbium (65) 1.0 × 104 2.7 × 10−7 1.0 × 107 2.7 × 10−4 Tb-158 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Tb-160 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Tc-95m Technetium (43) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Tc-96 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Tc-96m 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Tc-97 1.0 × 103 2.7 × 10−8 1.0 × 108 2.7 × 10−3 Tc-97m 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Tc-98 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Tc-99 1.0
× 104 2.7 × 10−7 1.0 × 107 2.7 × 10−4 Tc-99m 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Te-121 Tellurium (52) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Te-121m 1.0 × 10 2 2.7 × 10−9 1.0 × 10 6 2.7 × 10−5 Te-123m 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Te-125m 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Te-127 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Te-127m 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Te-129 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Te-129m 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Te-131m 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Te-132 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Th-227 Thorium (90) 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 Th
-228 (b) 1.0 2.7 × 10−11 1.0 × 104 2.7 × 10−7 Th-229 (b) 1.0 2.7 × 10−11 1.0 × 103 2.7 × 10−8 Th-230 1.0 2.7 × 10−11 1.0 × 104 2.7 × 10−7 Th-231 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Th-232 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 Th-234 (b) 1.0 × 103 2.7 × 10−8 1.0 × 105 2.7 × 10−6 Th (nat) (b) 1.0 2.7 × 10−11 1.0 × 103 2.7 × 10−8 Ti-44 Titanium (22) 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 Tl-200 Thallium (81) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Tl-201 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Tl-202 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Tl-204 1.0 × 104 2.7 × 10−7 1.0 × 104 2.7 × 10−7 Tm-167 Thulium (69) 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5
Tm-170 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Tm-171 1.0 × 104 2.7 × 10−7 1.0 × 108 2.7 × 10−3 U-230 (fast lung absorption) (b),(d) Uranium (92) 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 U-230 (medium lung absorption) (e) 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 U-230 (slow lung absorption) (f) 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 U-232 (fast lung absorption) (b),(d) 1.0 2.7 × 10−11 1.0 × 103 2.7 × 10−8 U-232 (medium lung absorption) (e) 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 U-232 (slow lung absorption) (f) 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 U-233 (fast lung absorption) (d) 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 U-233 (medium lung absorption) (e) 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 U-233 (slow lung absorption) (f) 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 U-234 (fast lung absorption) (d) 1.0 ×
101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 U-234 (medium lung absorption) (e) 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 U-234 (slow lung absorption) (f) 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 U-235 (all lung absorption types) (b),(d),(e),(f) 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 U-236 (fast lung absorption) (d) 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 U-236 (medium lung absorption) (e) 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 U-236 (slow lung absorption) (f) 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 U-238 (all lung absorption types) (b),(d),(e),(f) 1.0 × 101 2.7 × 10−10 1.0 × 104 2.7 × 10−7 U (nat) (b) 1.0 2.7 × 10−11 1.0 × 103 2.7 × 10−8 U (enriched to 20% or less)(g) 1.0 2.7 × 10−11 1.0 × 103 2.7 × 10−8 U (dep) 1.0 2.7 × 10−11 1.0 × 103 2.7 × 10−8 V-48 Vanadium (23) 1.0 × 101 2.7 × 10−10 1.0 × 105
2.7 × 10−6 V-49 1.0 × 104 2.7 × 10−7 1.0 × 107 2.7 × 10−4 W-178 Tungsten (74) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 W-181 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 W-185 1.0 × 104 2.7 × 10−7 1.0 × 107 2.7 × 10−4 W-187 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 W-188 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 Xe-122 Xenon (54) 1.0 × 102 2.7 × 10−9 1.0 × 109 2.7 × 10−2 Xe-123 1.0 × 102 2.7 × 10−9 1.0 × 109 2.7 × 10−2 Xe-127 1.0 × 103 2.7 × 10−8 1.0 × 105 2.7 × 10−6 Xe-131m 1.0 × 104 2.7 × 10−7 1.0 × 104 2.7 × 10−7 Xe-133 1.0 × 103 2.7 × 10−8 1.0 × 104 2.7 × 10−7 Xe-135 1.0 × 103 2.7 × 10−8 1.0 × 1010 2.7 × 10−1 Y-87 Yttrium (39) 1.0 × 101 2.7 ×
10−10 1.0 × 106 2.7 × 10−5 Y-88 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Y-90 1.0 × 103 2.7 × 10−8 1.0 × 105 2.7 × 10−6 Y-91 1.0 × 103 2.7 × 10−8 1.0 × 106 2.7 × 10−5 Y-91m 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Y-92 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 Y-93 1.0 × 102 2.7 × 10−9 1.0 × 105 2.7 × 10−6 Yb-169 Ytterbium (70) 1.0 × 102 2.7 × 10−9 1.0 × 107 2.7 × 10−4 Yb-175 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Zn-65 Zinc (30) 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Zn-69 1.0 × 104 2.7 × 10−7 1.0 × 106 2.7 × 10−5 Zn-69m 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Zr-88 Zirconium (40) 1.0 × 102 2.7 × 10−9 1.0 × 106 2.7 × 10−5 Zr-93 (b
) 1.0 × 103 2.7 × 10−8 1.0 × 107 2.7 × 10−4 Zr-95 1.0 × 101 2.7 × 10−10 1.0 × 106 2.7 × 10−5 Zr-97 (b) 1.0 × 101 2.7 × 10−10 1.0 × 105 2.7 × 10−6 a [Reserved] b Parent nuclides and their progeny included in secular equilibrium are listed as follows: Sr-90 Y-90 Zr-93 Nb-93m Zr-97 Nb-97 Ru-106 Rh-106 Ag-108m Ag-108 Cs-137 Ba-137m Ce-144 Pr-144 Ba-140 La-140 Bi-212 Tl-208 (0.36), Po-212 (0.64) Pb-210 Bi-210, Po-210 Pb-212 Bi-212, Tl-208 (0.36), Po-212 (0.64) Rn-222 Po-218, Pb-214, Bi-214, Po-214 Ra-223 Rn-219, Po-215, Pb-211, Bi-211, Tl-207 Ra-224 Rn-220, Po-216, Pb-212, Bi-212, Tl-208 (0.36), Po-212 (0.64), Ra-226 Rn-222, Po-218, Pb-214, Bi-214, Po-214, Pb-210, Bi-210, Po-210 Ra-228 Ac-228 Th-228 Ra-224, Rn-220, Po-216, Pb-212, Bi-212, Tl-208 (0.36), Po-212 (0.64) Th-229 Ra-225, Ac-225, Fr-221, At-217, Bi-213, Po-213, Pb-209 Th-nat Ra-228, Ac-228, Th-228, Ra-224, Rn-220, Po-216, Pb-212, Bi-212, Tl-
208 (0.36), Po-212 (0.64) Th-234 Pa-234m U-230 Th-226, Ra-222, Rn-218, Po-214 U-232 Th-228, Ra-224, Rn-220, Po-216, Pb-212, Bi-212, Tl-208 (0.36), Po-212 (0.64) U-235 Th-231 U-238 Th-234, Pa-234m U-nat Th-234, Pa-234m, U-234, Th-230, Ra-226, Rn-222, Po-218, Pb-214, Bi-214, Po-214, Pb-210, Bi-210, Po-210 Np-237 Pa-233 Am-242m Am-242 Am-243 Np-239 c [Reserved] d These values apply only to compounds of uranium that take the chemical form of UF6, UO2 F2 and UO2 (NO3)2 in both normal and accident conditions of transport. e These values apply only to compounds of uranium that take the chemical form of UO3, UF4, UCl4 and hexavalent compounds in both normal and accident conditions of transport. f These values apply to all compounds of uranium other than those specified in notes (d) and (e) of this table. g These values apply to unirradiated uranium only.
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