49 CFR 173.435: A1 and A2 values for radionuclides

Last reviewed: October 14, 2026

This section gives a table of A1 and A2 values for radionuclides, with specific activity for each. The regulatory standard units are Terabecquerels (TBq); the curie values are approximate and for information only. Footnotes explain parent radionuclides, uranium chemical forms and special cases.

What it says

  1. The section sets out a table of A1 and A2 values for radionuclides.

    “The table of A1 and A2 values for radionuclides is as follows:”
  2. The curie values of A1 and A2 are approximate and for information only; the regulatory standard units are Terabecquerels (TBq).

    49 CFR 173.435 b“The values of A1 and A2 in curies (Ci) are approximate and for information only; the regulatory standard units are Terabecquerels (TBq), (see § 171.10).”
  3. A1 and A2 values marked (a) for parent radionuclides include contributions from daughter nuclides with half-lives less than 10 days.

    49 CFR 173.435 a“A1 and/or A2 values for these parent radionuclides include contributions from daughter nuclides with half-lives less than 10 days”
  4. The activity of Ir-192 in special form may be determined from a measurement of the rate of decay or a measurement of the radiation level at a prescribed distance from the source.

    49 CFR 173.435 c“The activity of Ir-192 in special form may be determined from a measurement of the rate of decay or a measurement of the radiation level at a prescribed distance from the source.”
  5. Values marked (d) apply only to uranium compounds in the chemical form of UF6, UO2 F2 and UO2 (NO3)2, in both normal and accident conditions of transport.

    49 CFR 173.435 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.”
  6. Values marked (f) apply to all uranium compounds other than those specified in notes (d) and (e) of the table.

    49 CFR 173.435 f“These values apply to all compounds of uranium other than those specified in notes (d) and (e) of this table.”
  7. The A2 value for Mo-99 for domestic use is 0.74 TBq (20 Ci).

    49 CFR 173.435 i“A2 = 0.74 TBq (20 Ci) for Mo-99 for domestic use.”

Common questions

Are the curie values in the A1 and A2 table official?

No. The curie values are approximate and for information only, and the regulatory standard units are Terabecquerels (TBq).

“The values of A1 and A2 in curies (Ci) are approximate and for information only; the regulatory standard units are Terabecquerels (TBq), (see § 171.10).”

What is the A2 value for Mo-99 for domestic use?

The A2 value for Mo-99 for domestic use is 0.74 TBq (20 Ci).

“A2 = 0.74 TBq (20 Ci) for Mo-99 for domestic use.”

How may the activity of Ir-192 in special form be determined?

It may be determined from a measurement of the rate of decay or a measurement of the radiation level at a prescribed distance from the source.

“The activity of Ir-192 in special form may be determined from a measurement of the rate of decay or a measurement of the radiation level at a prescribed distance from the source.”

The text of 49 CFR 173.435

Electronic Code of Federal Regulations (eCFR), current as of April 16, 2026 · Read it on eCFR

Table of A1 and A2 values for radionuclides

The table of A1 and A2 values for radionuclides is as follows:

Symbol ofradionuclide Element andatomic number A1 (TBq) A1 (Ci) b A2 (TBq) A2 (Ci) b Specific activity

(TBq/g)

(Ci/g) Ac-225 (a) Actinium (89) 8.0 × 10−1 2.2 × 101 6.0 × 10−3 1.6 × 10−1 2.1 × 103 5.8 × 104 Ac-227 (a) 9.0 × 10−1 2.4 × 101 9.0 × 10−5 2.4 × 10−3 2.7 7.2 × 101 Ac-228 6.0 × 10−1 1.6 × 101 5.0 × 10−1 1.4 × 101 8.4 × 104 2.2 × 106 Ag-105 Silver (47) 2.0 5.4 × 101 2.0 5.4 × 101 1.1 × 103 3.0 × 104 Ag-108m (a) 7.0 × 10−1 1.9 × 101 7.0 × 10−1 1.9 × 101 9.7 × 10−1 2.6 × 101 Ag-110m (a) 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 1.8 × 102 4.7 × 103 Ag-111 2.0 5.4 × 101 6.0 × 10−1 1.6 × 101 5.8 × 103 1.6 × 105 Al-26 Aluminum (13) 1.0 × 10−1 2.7 1.0 × 10−1 2.7 7.0 × 10−4 1.9 × 10−2 Am-241 Americium (95) 1.0 × 101 2.7 × 102 1.0 × 10−3 2.7 × 10−2 1.3 × 10−1 3.4 Am-242m (a) 1.0 × 101 2.7 × 102

1.0 × 10−3 2.7 × 10−2 3.6 × 10−1 1.0 × 101 Am-243 (a) 5.0 1.4 × 102 1.0 × 10−3 2.7 × 10−2 7.4 × 10−3 2.0 × 10−1 Ar-37 Argon (18) 4.0 × 101 1.1 × 103 4.0 × 101 1.1 × 103 3.7 × 103 9.9 × 104 Ar-39 4.0 × 101 1.1 × 103 2.0 × 101 5.4 × 102 1.3 3.4 × 101 Ar-41 3.0 × 10−1 8.1 3.0 × 10−1 8.1 1.5 × 106 4.2 × 107 As-72 Arsenic (33) 3.0 × 10−1 8.1 3.0 × 10−1 8.1 6.2 × 104 1.7 × 106 As-73 4.0 × 101 1.1 × 103 4.0 × 101 1.1 × 103 8.2 × 102 2.2 × 104 As-74 1.0 2.7 × 101 9.0 × 10−1 2.4 × 101 3.7 × 103 9.9 × 104 As-76 3.0 × 10−1 8.1 3.0 × 10−1 8.1 5.8 × 104 1.6 × 106 As-77 2.0 × 101 5.4 × 102 7.0 × 10−1 1.9 × 101 3.9 × 104 1.0 × 106 At-211 (a) Astatine (85) 2.0 × 101 5.4 × 102 5.0 ×

10−1 1.4 × 101 7.6 × 104 2.1 × 106 Au-193 Gold (79) 7.0 1.9 × 102 2.0 5.4 × 101 3.4 × 104 9.2 × 105 Au-194 1.0 2.7 × 101 1.0 2.7 × 101 1.5 × 104 4.1 × 105 Au-195 1.0 × 101 2.7 × 102 6.0 1.6 × 102 1.4 × 102 3.7 × 103 Au-198 1.0 2.7 × 101 6.0 × 10−1 1.6 × 101 9.0 × 103 2.4 × 105 Au-199 1.0 × 101 2.7 × 102 6.0 × 10−1 1.6 × 101 7.7 × 103 2.1 × 105 Ba-131 (a) Barium (56) 2.0 5.4 × 101 2.0 5.4 × 101 3.1 × 103 8.4 × 104 Ba-133 3.0 8.1 × 101 3.0 8.1 × 101 9.4 2.6 × 102 Ba-133m 2.0 × 101 5.4 × 102 6.0 × 10−1 1.6 × 101 2.2 × 104 6.1 × 105 Ba-140 (a) 5.0 × 10−1 1.4 × 101 3.0 × 10−1 8.1 2.7 × 103 7.3 × 104 Be-7 Beryllium (4) 2.0 × 101 5.4 × 102 2.0 × 101 5.4 × 102 1.3 × 104 3.5 × 105 Be-10 4.0

× 101 1.1 × 103 6.0 × 10−1 1.6 × 101 8.3 × 10−4 2.2 × 10−2 Bi-205 Bismuth (83) 7.0 × 10−1 1.9 × 101 7.0 × 10−1 1.9 × 101 1.5 × 103 4.2 × 104 Bi-206 3.0 × 10−1 8.1 3.0 × 10−1 8.1 3.8 × 103 1.0 × 105 Bi-207 7.0 × 10−1 1.9 × 101 7.0 × 10−1 1.9 × 101 1.9 5.2 × 101 Bi-210 1.0 2.7 × 101 6.0 × 10−1 1.6 × 101 4.6 × 103 1.2 × 105 Bi-210m (a) 6.0 × 10−1 1.6 × 101 2.0 × 10−2 5.4 × 10−1 2.1 × 10−5 5.7 × 10−4 Bi-212 (a) 7.0 × 10−1 1.9 × 101 6.0 × 10−1 1.6 × 101 5.4 × 105 1.5 × 107 Bk-247 Berkelium (97) 8.0 2.2 × 102 8.0 × 10−4 2.2 × 10−2 3.8 × 10−2 1.0 Bk-249 (a) 4.0 × 101 1.1 × 103 3.0 × 10−1 8.1 6.1 × 101 1.6 × 103 Br-76 Bromine (35) 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1

× 101 9.4 × 104 2.5 × 106 Br-77 3.0 8.1 × 101 3.0 8.1 × 101 2.6 × 104 7.1 × 105 Br-82 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 4.0 × 104 1.1 × 106 C-11 Carbon (6) 1.0 2.7 × 101 6.0 × 10−1 1.6 × 101 3.1 × 107 8.4 × 108 C-14 4.0 × 101 1.1 × 103 3.0 8.1 × 101 1.6 × 10−1 4.5 Ca-41 Calcium (20) Unlimited Unlimited Unlimited Unlimited 3.1 × 10−3 8.5 × 10−2 Ca-45 4.0 × 101 1.1 × 103 1.0 2.7 × 101 6.6 × 102 1.8 × 104 Ca-47 (a) 3.0 8.1 × 101 3.0 × 10−1 8.1 2.3 × 104 6.1 × 105 Cd-109 Cadmium (48) 3.0 × 101 8.1 × 102 2.0 5.4 × 101 9.6 × 101 2.6 × 103 Cd-113m 4.0 × 101 1.1 × 103 5.0 × 10−1 1.4 × 101 8.3 2.2 × 102 Cd-115 (a) 3.0 8.1 × 101 4.0 × 10−1 1.1 × 101 1.9 × 104 5.1 × 105 Cd-115m 5.0 × 10−1 1.4 × 101

5.0 × 10−1 1.4 × 101 9.4 × 102 2.5 × 104 Ce-139 Cerium (58) 7.0 1.9 × 102 2.0 5.4 × 101 2.5 × 102 6.8 × 103 Ce-141 2.0 × 101 5.4 × 102 6.0 × 10−1 1.6 × 101 1.1 × 103 2.8 × 104 Ce-143 9.0 × 10−1 2.4 × 101 6.0 × 10−1 1.6 × 101 2.5 × 104 6.6 × 105 Ce-144 (a) 2.0 × 10−1 5.4 2.0 × 10−1 5.4 1.2 × 102 3.2 × 103 Cf-248 Californium (98) 4.0 × 101 1.1 × 103 6.0 × 10−3 1.6 × 10−1 5.8 × 101 1.6 × 103 Cf-249 3.0 8.1 × 101 8.0 × 10−4 2.2 × 10−2 1.5 × 10−1 4.1 Cf-250 2.0 × 101 5.4 × 102 2.0 × 10−3 5.4 × 10−2 4.0 1.1 × 102 Cf-251 7.0 1.9 × 102 7.0 × 10−4 1.9 × 10−2 5.9 × 10−2 1.6 Cf-252 1 × 10−1 2.7 3.0 × 10−3 8.1 × 10−2 2.0 × 10 1 5.4 × 10 2 Cf-253 (a) 4.0 × 101 1.1

× 103 4.0 × 10−2 1.1 1.1 × 103 2.9 × 104 Cf-254 1.0 × 10−3 2.7 × 10−2 1.0 × 10−3 2.7 × 10−2 3.1 × 102 8.5 × 103 Cl-36 Chlorine (17) 1.0 × 101 2.7 × 102 6.0 × 10−1 1.6 × 101 1.2 × 10−3 3.3 × 10−2 Cl-38 2.0 × 10−1 5.4 2.0 × 10−1 5.4 4.9 × 106 1.3 × 108 Cm-240 Curium (96) 4.0 × 101 1.1 × 103 2.0 × 10−2 5.4 × 10−1 7.5 × 102 2.0 × 104 Cm-241 2.0 5.4 × 101 1.0 2.7 × 101 6.1 × 102 1.7 × 104 Cm-242 4.0 × 101 1.1 × 103 1.0 × 10−2 2.7 × 10−1 1.2 × 102 3.3 × 103 Cm-243 9.0 2.4 × 102 1.0 × 10−3 2.7 × 10−2 1.9 5.2 × 101 Cm-244 2.0 × 101 5.4 × 102 2.0 × 10−3 5.4 × 10−2 3.0 8.1 × 101 Cm-245 9.0 2.4 × 102 9.0 × 10−4 2.4 × 10−2 6.4 × 10−3 1.7 × 10−1 Cm-246 9.

0 2.4 × 102 9.0 × 10−4 2.4 × 10−2 1.1 × 10−2 3.1 × 10−1 Cm-247 (a) 3.0 8.1 × 101 1.0 × 10−3 2.7 × 10−2 3.4 × 10−6 9.3 × 10−5 Cm-248 2.0 × 10−2 5.4 × 10−1 3.0 × 10−4 8.1 × 10−3 1.6 × 10−4 4.2 × 10−3 Co-55 Cobalt (27) 5.0 × 10−1 1.4 × 101 5.0 × 10−1 1.4 × 101 1.1 × 105 3.1 × 106 Co-56 3.0 × 10−1 8.1 3.0 × 10−1 8.1 1.1 × 103 3.0 × 104 Co-57 1.0 × 101 2.7 × 102 1.0 × 101 2.7 × 102 3.1 × 102 8.4 × 103 Co-58 1.0 2.7 × 101 1.0 2.7 × 101 1.2 × 103 3.2 × 104 Co-58m 4.0 × 101 1.1 × 103 4.0 × 101 1.1 × 103 2.2 × 105 5.9 × 106 Co-60 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 4.2 × 101 1.1 × 103 Cr-51 Chromium (24) 3.0 × 101 8.1 × 102 3.0 × 101 8.1 × 102 3.4 × 103 9.2

× 104 Cs-129 Cesium (55) 4.0 1.1 × 102 4.0 1.1 × 102 2.8 × 104 7.6 × 105 Cs-131 3.0 × 101 8.1 × 102 3.0 × 101 8.1 × 102 3.8 × 103 1.0 × 105 Cs-132 1.0 2.7 × 101 1.0 2.7 × 101 5.7 × 103 1.5 × 105 Cs-134 7.0 × 10−1 1.9 × 101 7.0 × 10−1 1.9 × 101 4.8 × 101 1.3 × 103 Cs-134m 4.0 × 101 1.1 × 103 6.0 × 10−1 1.6 × 101 3.0 × 105 8.0 × 106 Cs-135 4.0 × 101 1.1 × 103 1.0 2.7 × 101 4.3 × 10−5 1.2 × 10−3 Cs-136 5.0 × 10−1 1.4 × 101 5.0 × 10−1 1.4 × 101 2.7 × 103 7.3 × 104 Cs-137 (a) 2.0 5.4 × 101 6.0 × 10−1 1.6 × 101 3.2 8.7 × 101 Cu-64 Copper (29) 6.0 1.6 × 102 1.0 2.7 × 101 1.4 × 105 3.9 × 106 Cu-67 1.0 × 101 2.7 × 102 7.0 × 10−1 1.9 × 101 2.8 × 104 7.6 × 105 Dy-159 Dysprosium (66) 2.0 × 101

5.4 × 102 2.0 × 101 5.4 × 102 2.1 × 102 5.7 × 103 Dy-165 9.0 × 10−1 2.4 × 101 6.0 × 10−1 1.6 × 101 3.0 × 105 8.2 × 106 Dy-166 (a) 9.0 × 10−1 2.4 × 101 3.0 × 10−1 8.1 8.6 × 103 2.3 × 105 Er-169 Erbium (68) 4.0 × 101 1.1 × 103 1.0 2.7 × 101 3.1 × 103 8.3 × 104 Er-171 8.0 × 10−1 2.2 × 101 5.0 × 10−1 1.4 × 101 9.0 × 104 2.4 × 106 Eu-147 Europium (63) 2.0 5.4 × 101 2.0 5.4 × 101 1.4 × 103 3.7 × 104 Eu-148 5.0 × 10−1 1.4 × 101 5.0 × 10−1 1.4 × 101 6.0 × 102 1.6 × 104 Eu-149 2.0 × 101 5.4 × 102 2.0 × 101 5.4 × 102 3.5 × 102 9.4 × 103 Eu-150 (short lived) 2.0 5.4 × 101 7.0 × 10−1 1.9 × 101 6.1 × 104 1.6 × 106 Eu-150 (long lived) 7.0 × 10−1 1.9 × 101 7.0 × 10−1 1.9 × 101 6.1 × 104 1.6 × 106 Eu-152 1.0 2.

7 × 101 1.0 2.7 × 101 6.5 1.8 × 102 Eu-152m 8.0 × 10−1 2.2 × 101 8.0 × 10−1 2.2 × 101 8.2 × 104 2.2 × 106 Eu-154 9.0 × 10−1 2.4 × 101 6.0 × 10−1 1.6 × 101 9.8 2.6 × 102 Eu-155 2.0 × 101 5.4 × 102 3.0 8.1 × 101 1.8 × 101 4.9 × 102 Eu-156 7.0 × 10−1 1.9 × 101 7.0 × 10−1 1.9 × 101 2.0 × 103 5.5 × 104 F-18 Fluorine (9) 1.0 2.7 × 101 6.0 × 10−1 1.6 × 101 3.5 × 106 9.5 × 107 Fe-52 (a) Iron (26) 3.0 × 10−1 8.1 3.0 × 10−1 8.1 2.7 × 105 7.3 × 106 Fe-55 4.0 × 101 1.1 × 103 4.0 × 101 1.1 × 103 8.8 × 101 2.4 × 103 Fe-59 9.0 × 10−1 2.4 × 101 9.0 × 10−1 2.4 × 101 1.8 × 103 5.0 × 104 Fe-60 (a) 4.0 × 101 1.1 × 103 2.0 × 10−1 5.4 7.4 × 10−4 2.0 × 10−2 Ga-67 Gallium (31) 7.0 1.9 × 102

3.0 8.1 × 101 2.2 × 104 6.0 × 105 Ga-68 5.0 × 10−1 1.4 × 101 5.0 × 10−1 1.4 × 101 1.5 × 106 4.1 × 107 Ga-72 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 1.1 × 105 3.1 × 106 Gd-146 (a) Gadolinium (64) 5.0 × 10−1 1.4 × 101 5.0 × 10−1 1.4 × 101 6.9 × 102 1.9 × 104 Gd-148 2.0 × 101 5.4 × 102 2.0 × 10−3 5.4 × 10−2 1.2 3.2 × 101 Gd-153 1.0 × 101 2.7 × 102 9.0 2.4 × 102 1.3 × 102 3.5 × 103 Gd-159 3.0 8.1 × 101 6.0 × 10−1 1.6 × 101 3.9 × 104 1.1 × 106 Ge-68 (a) Germanium (32) 5.0 × 10−1 1.4 × 101 5.0 × 10−1 1.4 × 101 2.6 × 102 7.1 × 103 Ge-71 4.0 × 101 1.1 × 103 4.0 × 101 1.1 × 103 5.8 × 103 1.6 × 105 Ge-77 3.0 × 10−1 8.1 3.0 × 10−1 8.1 1.3 × 105 3.6 × 106 Hf-172 (a) Hafnium (72) 6.0 ×

10−1 1.6 × 101 6.0 × 10−1 1.6 × 101 4.1 × 101 1.1 × 103 Hf-175 3.0 8.1 × 101 3.0 8.1 × 101 3.9 × 102 1.1 × 104 Hf-181 2.0 5.4 × 101 5.0 × 10−1 1.4 × 101 6.3 × 102 1.7 × 104 Hf-182 Unlimited Unlimited Unlimited Unlimited 8.1 × 10−6 2.2 × 10−4 Hg-194 (a) Mercury (80) 1.0 2.7 × 101 1.0 2.7 × 101 1.3 × 10−1 3.5 Hg-195m (a) 3.0 8.1 × 101 7.0 × 10−1 1.9 × 101 1.5 × 104 4.0 × 105 Hg-197 2.0 × 101 5.4 × 102 1.0 × 101 2.7 × 102 9.2 × 103 2.5 × 105 Hg-197m 1.0 × 101 2.7 × 102 4.0 × 10−1 1.1 × 101 2.5 × 104 6.7 × 105 Hg-203 5.0 1.4 × 102 1.0 2.7 × 101 5.1 × 102 1.4 × 104 Ho-166 Holmium (67) 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 2.6 × 104 7.0 × 105 Ho-166m 6.0 × 10−1 1.6 × 101 5.0 × 10−1 1.4 ×

101 6.6 × 10−2 1.8 I-123 Iodine (53) 6.0 1.6 × 102 3.0 8.1 × 101 7.1 × 104 1.9 × 106 I-124 1.0 2.7 × 101 1.0 2.7 × 101 9.3 × 103 2.5 × 105 I-125 2.0 × 101 5.4 × 102 3.0 8.1 × 101 6.4 × 102 1.7 × 104 I-126 2.0 5.4 × 101 1.0 2.7 × 101 2.9 × 103 8.0 × 104 I-129 Unlimited Unlimited Unlimited Unlimited 6.5 × 10−6 1.8 × 10−4 I-131 3.0 8.1 × 101 7.0 × 10−1 1.9 × 101 4.6 × 103 1.2 × 105 I-132 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 3.8 × 105 1.0 × 107 I-133 7.0 × 10−1 1.9 × 101 6.0 × 10−1 1.6 × 101 4.2 × 104 1.1 × 106 I-134 3.0 × 10−1 8.1 3.0 × 10−1 8.1 9.9 × 105 2.7 × 107 I-135 (a) 6.0 × 10−1 1.6 × 101 6.0 × 10−1 1.6 × 101 1.3 × 105 3.5 × 106 In-111 Indium (49) 3.0 8.1 × 101 3.0 8.1 ×

101 1.5 × 104 4.2 × 105 In-113m 4.0 1.1 × 102 2.0 5.4 × 101 6.2 × 105 1.7 × 107 In-114m (a) 1.0 × 101 2.7 × 102 5.0 × 10−1 1.4 × 101 8.6 × 102 2.3 × 104 In-115m 7.0 1.9 × 102 1.0 2.7 × 101 2.2 × 105 6.1 × 106 Ir-189 (a) Iridium (77) 1.0 × 101 2.7 × 102 1.0 × 101 2.7 × 102 1.9 × 103 5.2 × 104 Ir-190 7.0 × 10−1 1.9 × 101 7.0 × 10−1 1.9 × 101 2.3 × 103 6.2 × 104 Ir-192 (c) 1.0 2.7 × 101 6.0 × 10−1 1.6 × 101 3.4 × 102 9.2 × 103 Ir-194 3.0 × 10−1 8.1 3.0 × 10−1 8.1 3.1 × 104 8.4 × 105 K-40 Potassium (19) 9.0 × 10−1 2.4 × 101 9.0 × 10−1 2.4 × 101 2.4 × 10−7 6.4 × 10−6 K-42 2.0 × 10−1 5.4 2.0 × 10−1 5.4 2.2 × 105 6.0 × 106 K-43 7.0 × 10−1 1.9 × 101 6.0 × 10−1 1.6 × 101 1.2 ×

105 3.3 × 106 Kr-79 Krypton (36) 4.0 × 10 0 1.1 × 10 2 2.0 × 10 0 5.4 × 10 1 4.2 × 10 4 1.1 × 10 6 Kr-81 Krypton (36) 4.0 × 101 1.1 × 103 4.0 × 101 1.1 × 103 7.8 × 10−4 2.1 × 10−2 Kr-85 1.0 × 101 2.7 × 102 1.0 × 101 2.7 × 102 1.5 × 101 3.9 × 102 Kr-85m 8.0 2.2 × 102 3.0 8.1 × 101 3.0 × 105 8.2 × 106 Kr-87 2.0 × 10−1 5.4 2.0 × 10−1 5.4 1.0 × 106 2.8 × 107 La-137 Lanthanum (57) 3.0 × 101 8.1 × 102 6.0 1.6 × 102 1.6 × 10−3 4.4 × 10−2 La-140 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 2.1 × 104 5.6 × 105 Lu-172 Lutetium (71) 6.0 × 10−1 1.6 × 101 6.0 × 10−1 1.6 × 101 4.2 × 103 1.1 × 105 Lu-173 8.0 2.2 × 102 8.0 2.2 × 102 5.6 × 101 1.5 × 103 Lu-174 9.0 2.4 × 102 9.0 2.4 × 102 2.3

× 101 6.2 × 102 Lu-174m 2.0 × 101 5.4 × 102 1.0 × 101 2.7 × 102 2.0 × 102 5.3 × 103 Lu-177 3.0 × 101 8.1 × 102 7.0 × 10−1 1.9 × 101 4.1 × 103 1.1 × 105 Mg-28 (a) Magnesium (12) 3.0 × 10−1 8.1 3.0 × 10−1 8.1 2.0 × 105 5.4 × 106 Mn-52 Manganese (25) 3.0 × 10−1 8.1 3.0 × 10−1 8.1 1.6 × 104 4.4 × 105 Mn-53 Unlimited Unlimited Unlimited Unlimited 6.8 × 10−5 1.8 × 10−3 Mn-54 1.0 2.7 × 101 1.0 2.7 × 101 2.9 × 102 7.7 × 103 Mn-56 3.0 × 10−1 8.1 3.0 × 10−1 8.1 8.0 × 105 2.2 × 107 Mo-93 Molybdenum (42) 4.0 × 101 1.1 × 103 2.0 × 101 5.4 × 102 4.1 × 10−2 1.1 Mo-99(a)(i) 1.0 2.7 × 10 1 6.0 × 10−1 1.6 × 10 1 1.8 × 10 4 4.8 × 10 5 N-13 Nitrogen (7) 9.0 × 10−1 2.4 × 101 6.0 × 10−1 1.6 × 101 5.4 × 107 1.

5 × 109 Na-22 Sodium (11) 5.0 × 10−1 1.4 × 101 5.0 × 10−1 1.4 × 101 2.3 × 102 6.3 × 103 Na-24 2.0 × 10−1 5.4 2.0 × 10−1 5.4 3.2 × 105 8.7 × 106 Nb-93m Niobium (41) 4.0 × 101 1.1 × 103 3.0 × 101 8.1 × 102 8.8 2.4 × 102 Nb-94 7.0 × 10−1 1.9 × 101 7.0 × 10−1 1.9 × 101 6.9 × 10−3 1.9 × 10−1 Nb-95 1.0 2.7 × 101 1.0 2.7 × 101 1.5 × 103 3.9 × 104 Nb-97 9.0 × 10−1 2.4 × 101 6.0 × 10−1 1.6 × 101 9.9 × 105 2.7 × 107 Nd-147 Neodymium (60) 6.0 1.6 × 102 6.0 × 10−1 1.6 × 101 3.0 × 103 8.1 × 104 Nd-149 6.0 × 10−1 1.6 × 101 5.0 × 10−1 1.4 × 101 4.5 × 105 1.2 × 107 Ni-59 Nickel (28) Unlimited Unlimited Unlimited Unlimited 3.0 × 10−3 8.0 × 10−2 Ni-63 4.0 × 101 1.1 × 103 3.0 × 101 8.1 × 102 2.1 5.7 × 101 Ni-65 4.0

× 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 7.1 × 105 1.9 × 107 Np-235 Neptunium (93) 4.0 × 101 1.1 × 103 4.0 × 101 1.1 × 103 5.2 × 101 1.4 × 103 Np-236 (short-lived) 2.0 × 101 5.4 × 102 2.0 5.4 × 101 4.7 × 10−4 1.3 × 10−2 Np-236 (long-lived) 9.0 × 100 2.4 × 102 2.0 × 10−2 5.4 × 10−1 4.7 × 10−4 1.3 × 10−2 Np-237 2.0 × 101 5.4 × 102 2.0 × 10−3 5.4 × 10−2 2.6 × 10−5 7.1 × 10−4 Np-239 7.0 1.9 × 102 4.0 × 10−1 1.1 × 101 8.6 × 103 2.3 × 105 Os-185 Osmium (76) 1.0 2.7 × 101 1.0 2.7 × 101 2.8 × 102 7.5 × 103 Os-191 1.0 × 101 2.7 × 102 2.0 5.4 × 101 1.6 × 103 4.4 × 104 Os-191m 4.0 × 101 1.1 × 103 3.0 × 101 8.1 × 102 4.6 × 104 1.3 × 106 Os-193 2.0 5.4 × 101 6.0 × 10−1 1.6 × 101 2.0 × 104 5.3 × 105

Os-194 (a) 3.0 × 10−1 8.1 3.0 × 10−1 8.1 1.1 × 101 3.1 × 102 P-32 Phosphorus (15) 5.0 × 10−1 1.4 × 101 5.0 × 10−1 1.4 × 101 1.1 × 104 2.9 × 105 P-33 4.0 × 101 1.1 × 103 1.0 2.7 × 101 5.8 × 103 1.6 × 105 Pa-230 (a) Protactinium (91) 2.0 5.4 × 101 7.0 × 10−2 1.9 1.2 × 103 3.3 × 104 Pa-231 4.0 1.1 × 102 4.0 × 10−4 1.1 × 10−2 1.7 × 10−3 4.7 × 10−2 Pa-233 5.0 1.4 × 102 7.0 × 10−1 1.9 × 101 7.7 × 102 2.1 × 104 Pb-201 Lead (82) 1.0 2.7 × 101 1.0 2.7 × 101 6.2 × 104 1.7 × 106 Pb-202 4.0 × 101 1.1 × 103 2.0 × 101 5.4 × 102 1.2 × 10−4 3.4 × 10−3 Pb-203 4.0 1.1 × 102 3.0 8.1 × 101 1.1 × 104 3.0 × 105 Pb-205 Unlimited Unlimited Unlimited Unlimited 4.5 × 10−6 1.2 × 10−4 Pb-210 (a) 1.0 2.7 × 101 5.0 × 10−

2 1.4 2.8 7.6 × 101 Pb-212 (a) 7.0 × 10−1 1.9 × 101 2.0 × 10−1 5.4 5.1 × 104 1.4 × 106 Pd-103 (a) Palladium (46) 4.0 × 101 1.1 × 103 4.0 × 101 1.1 × 103 2.8 × 103 7.5 × 104 Pd-107 Unlimited Unlimited Unlimited Unlimited 1.9 × 10−5 5.1 × 10−4 Pd-109 2.0 5.4 × 101 5.0 × 10−1 1.4 × 101 7.9 × 104 2.1 × 106 Pm-143 Promethium (61) 3.0 8.1 × 101 3.0 8.1 × 101 1.3 × 102 3.4 × 103 Pm-144 7.0 × 10−1 1.9 × 101 7.0 × 10−1 1.9 × 101 9.2 × 101 2.5 × 103 Pm-145 3.0 × 101 8.1 × 102 1.0 × 101 2.7 × 102 5.2 1.4 × 102 Pm-147 4.0 × 101 1.1 × 103 2.0 5.4 × 101 3.4 × 101 9.3 × 102 Pm-148m (a) 8.0 × 10−1 2.2 × 101 7.0 × 10−1 1.9 × 101 7.9 × 102 2.1 × 104 Pm-149 2.0 5.4 × 101 6.0 × 10−1 1.6 × 101 1.5 × 104 4.0 × 105

Pm-151 2.0 5.4 × 101 6.0 × 10−1 1.6 × 101 2.7 × 104 7.3 × 105 Po-210 Polonium (84) 4.0 × 101 1.1 × 103 2.0 × 10−2 5.4 × 10−1 1.7 × 102 4.5 × 103 Pr-142 Praseodymium (59) 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 4.3 × 104 1.2 × 106 Pr-143 3.0 8.1 × 101 6.0 × 10−1 1.6 × 101 2.5 × 103 6.7 × 104 Pt-188 (a) Platinum (78) 1.0 2.7 × 101 8.0 × 10−1 2.2 × 101 2.5 × 103 6.8 × 104 Pt-191 4.0 1.1 × 102 3.0 8.1 × 101 8.7 × 103 2.4 × 105 Pt-193 4.0 × 101 1.1 × 103 4.0 × 101 1.1 × 103 1.4 3.7 × 101 Pt-193m 4.0 × 101 1.1 × 103 5.0 × 10−1 1.4 × 101 5.8 × 103 1.6 × 105 Pt-195m 1.0 × 101 2.7 × 102 5.0 × 10−1 1.4 × 101 6.2 × 103 1.7 × 105 Pt-197 2.0 × 101 5.4 × 102 6.0 × 10−1 1.6 × 101 3.2 × 104 8.7 × 105 Pt-197

m 1.0 × 101 2.7 × 102 6.0 × 10−1 1.6 × 101 3.7 × 105 1.0 × 107 Pu-236 Plutonium (94) 3.0 × 101 8.1 × 102 3.0 × 10−3 8.1 × 10−2 2.0 × 101 5.3 × 102 Pu-237 2.0 × 101 5.4 × 102 2.0 × 101 5.4 × 102 4.5 × 102 1.2 × 104 Pu-238 1.0 × 101 2.7 × 102 1.0 × 10−3 2.7 × 10−2 6.3 × 10−1 1.7 × 101 Pu-239 1.0 × 101 2.7 × 102 1.0 × 10−3 2.7 × 10−2 2.3 × 10−3 6.2 × 10−2 Pu-240 1.0 × 101 2.7 × 102 1.0 × 10−3 2.7 × 10−2 8.4 × 10−3 2.3 × 10−1 Pu-241 (a) 4.0 × 101 1.1 × 103 6.0 × 10−2 1.6 3.8 1.0 × 102 Pu-242 1.0 × 101 2.7 × 102 1.0 × 10−3 2.7 × 10−2 1.5 × 10−4 3.9 × 10−3 Pu-244 (a) 4.0 × 10−1 1.1 × 101 1.0 × 10−3 2.7 × 10−2 6.7 × 10−7 1.8 × 10−5 Ra-223 (a) Radium (88) 4.0 × 10−1 1.1 ×

101 7.0 × 10−3 1.9 × 10−1 1.9 × 103 5.1 × 104 Ra-224 (a) 4.0 × 10−1 1.1 × 101 2.0 × 10−2 5.4 × 10−1 5.9 × 103 1.6 × 105 Ra-225 (a) 2.0 × 10−1 5.4 4.0 × 10−3 1.1 × 10−1 1.5 × 103 3.9 × 104 Ra-226 (a) 2.0 × 10−1 5.4 3.0 × 10−3 8.1 × 10−2 3.7 × 10−2 1.0 Ra-228 (a) 6.0 × 10−1 1.6 × 101 2.0 × 10−2 5.4 × 10−1 1.0 × 101 2.7 × 102 Rb-81 Rubidium (37) 2.0 5.4 × 101 8.0 × 10−1 2.2 × 101 3.1 × 105 8.4 × 106 Rb-83 (a) 2.0 5.4 × 101 2.0 5.4 × 101 6.8 × 102 1.8 × 104 Rb-84 1.0 2.7 × 101 1.0 2.7 × 101 1.8 × 103 4.7 × 104 Rb-86 5.0 × 10−1 1.4 × 101 5.0 × 10−1 1.4 × 101 3.0 × 103 8.1 × 104 Rb-87 Unlimited Unlimited Unlimited Unlimited 3.2 × 10−9 8.6 × 10−8 Rb(nat) Unlimited Unlimited Unlimited Unlimited 6.7 ×

10 −10 1.8 × 10 −8 Re-184 Rhenium (75) 1.0 2.7 × 101 1.0 2.7 × 101 6.9 × 102 1.9 × 104 Re-184m 3.0 8.1 × 101 1.0 2.7 × 101 1.6 × 102 4.3 × 103 Re-186 2.0 5.4 × 101 6.0 × 10−1 1.6 × 101 6.9 × 103 1.9 × 105 Re-187 Unlimited Unlimited Unlimited Unlimited 1.4 × 10−9 3.8 × 10−8 Re-188 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 3.6 × 104 9.8 × 105 Re-189 (a) 3.0 8.1 × 101 6.0 × 10−1 1.6 × 101 2.5 × 104 6.8 × 105 Re(nat) Unlimited Unlimited Unlimited Unlimited 0.0 2.4 × 10−8 Rh-99 Rhodium (45) 2.0 5.4 × 101 2.0 5.4 × 101 3.0 × 103 8.2 × 104 Rh-101 4.0 1.1 × 102 3.0 8.1 × 101 4.1 × 101 1.1 × 103 Rh-102 5.0 × 10−1 1.4 × 101 5.0 × 10−1 1.4 × 101 4.5 × 101 1.2 × 103 Rh-102m 2.0 5.4 × 101 2.0 5.4 × 101 2.3 × 102 6.2 × 103 Rh-103m 4.

0 × 101 1.1 × 103 4.0 × 101 1.1 × 103 1.2 × 106 3.3 × 107 Rh-105 1.0 × 101 2.7 × 102 8.0 × 10−1 2.2 × 101 3.1 × 104 8.4 × 105 Rn-222 (a) Radon (86) 3.0 × 10−1 8.1 4.0 × 10−3 1.1 × 10−1 5.7 × 103 1.5 × 105 Ru-97 Ruthenium (44) 5.0 1.4 × 102 5.0 1.4 × 102 1.7 × 104 4.6 × 105 Ru-103 (a) 2.0 5.4 × 101 2.0 5.4 × 101 1.2 × 103 3.2 × 104 Ru-105 1.0 2.7 × 101 6.0 × 10−1 1.6 × 101 2.5 × 105 6.7 × 106 Ru-106 (a) 2.0 × 10−1 5.4 2.0 × 10−1 5.4 1.2 × 102 3.3 × 103 S-35 Sulphur (16) 4.0 × 101 1.1 × 103 3.0 8.1 × 101 1.6 × 103 4.3 × 104 Sb-122 Antimony (51) 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 1.5 × 104 4.0 × 105 Sb-124 6.0 × 10−1 1.6 × 101 6.0 × 10−1 1.6 × 101 6.5 × 102 1.7 × 104 Sb-125 2

.0 5.4 × 101 1.0 2.7 × 101 3.9 × 101 1.0 × 103 Sb-126 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 3.1 × 103 8.4 × 104 Sc-44 Scandium (21) 5.0 × 10−1 1.4 × 101 5.0 × 10−1 1.4 × 101 6.7 × 105 1.8 × 107 Sc-46 5.0 × 10−1 1.4 × 101 5.0 × 10−1 1.4 × 101 1.3 × 103 3.4 × 104 Sc-47 1.0 × 101 2.7 × 102 7.0 × 10−1 1.9 × 101 3.1 × 104 8.3 × 105 Sc-48 3.0 × 10−1 8.1 3.0 × 10−1 8.1 5.5 × 104 1.5 × 106 Se-75 Selenium (34) 3.0 8.1 × 101 3.0 8.1 × 101 5.4 × 102 1.5 × 104 Se-79 4.0 × 101 1.1 × 103 2.0 5.4 × 101 2.6 × 10−3 7.0 × 10−2 Si-31 Silicon (14) 6.0 × 10−1 1.6 × 101 6.0 × 10−1 1.6 × 101 1.4 × 106 3.9 × 107 Si-32 4.0 × 101 1.1 × 103 5.0 × 10−1 1.4 × 101 3.9 1.1 × 102 Sm-145 Samarium (62) 1.

0 × 101 2.7 × 102 1.0 × 101 2.7 × 102 9.8 × 101 2.6 × 103 Sm-147 Unlimited Unlimited Unlimited Unlimited 8.5 × 10−10 2.3 × 10−8 Sm-151 4.0 × 101 1.1 × 103 1.0 × 101 2.7 × 102 9.7 × 10−1 2.6 × 101 Sm-153 9.0 2.4 × 102 6.0 × 10−1 1.6 × 101 1.6 × 104 4.4 × 105 Sn-113 (a) Tin (50) 4.0 1.1 × 102 2.0 5.4 × 101 3.7 × 102 1.0 × 104 Sn-117m 7.0 1.9 × 102 4.0 × 10−1 1.1 × 101 3.0 × 103 8.2 × 104 Sn-119m 4.0 × 101 1.1 × 103 3.0 × 101 8.1 × 102 1.4 × 102 3.7 × 103 Sn-121m (a) 4.0 × 101 1.1 × 103 9.0 × 10−1 2.4 × 101 2.0 5.4 × 101 Sn-123 8.0 × 10−1 2.2 × 101 6.0 × 10−1 1.6 × 101 3.0 × 102 8.2 × 103 Sn-125 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 4.0 × 103 1.1 × 105 Sn-126 (a) 6.0 × 10−1 1.6 × 101 4.0 × 10−1 1.

1 × 101 1.0 × 10−3 2.8 × 10−2 Sr-82 (a) Strontium (38) 2.0 × 10−1 5.4 2.0 × 10−1 5.4 2.3 × 103 6.2 × 104 Sr-85 2.0 5.4 × 101 2.0 5.4 × 101 8.8 × 102 2.4 × 104 Sr-85m 5.0 1.4 × 102 5.0 1.4 × 102 1.2 × 106 3.3 × 107 Sr-87m 3.0 8.1 × 101 3.0 8.1 × 101 4.8 × 105 1.3 × 107 Sr-89 6.0 × 10−1 1.6 × 101 6.0 × 10−1 1.6 × 101 1.1 × 103 2.9 × 104 Sr-90 (a) 3.0 × 10−1 8.1 3.0 × 10−1 8.1 5.1 1.4 × 102 Sr-91 (a) 3.0 × 10−1 8.1 3.0 × 10−1 8.1 1.3 × 105 3.6 × 106 Sr-92 (a) 1.0 2.7 × 101 3.0 × 10−1 8.1 4.7 × 105 1.3 × 107 T(H-3) Tritium (1) 4.0 × 101 1.1 × 103 4.0 × 101 1.1 × 103 3.6 × 102 9.7 × 103 Ta-178 (long-lived) Tantalum (73) 1.0 2.7 × 101 8.0 × 10−1 2.2 × 101 4.2 × 106 1.1 × 108 Ta

-179 3.0 × 101 8.1 × 102 3.0 × 101 8.1 × 102 4.1 × 101 1.1 × 103 Ta-182 9.0 × 10−1 2.4 × 101 5.0 × 10−1 1.4 × 101 2.3 × 102 6.2 × 103 Tb-157 Terbium (65) 4.0 × 101 1.1 × 103 4.0 × 101 1.1 × 103 5.6 × 10−1 1.5 × 101 Tb-158 1.0 2.7 × 101 1.0 2.7 × 101 5.6 × 10−1 1.5 × 101 Tb-160 1.0 2.7 × 101 6.0 × 10−1 1.6 × 101 4.2 × 102 1.1 × 104 Tc-95m (a) Technetium (43) 2.0 5.4 × 101 2.0 5.4 × 101 8.3 × 102 2.2 × 104 Tc-96 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 1.2 × 104 3.2 × 105 Tc-96m (a) 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 1.4 × 106 3.8 × 107 Tc-97 Unlimited Unlimited Unlimited Unlimited 5.2 × 10−5 1.4 × 10−3 Tc-97m 4.0 × 101 1.1 × 103 1.0 2.7 × 101 5.6 × 102 1.5 × 104 Tc-98 8.0 × 10−1

2.2 × 101 7.0 × 10−1 1.9 × 101 3.2 × 10−5 8.7 × 10−4 Tc-99 4.0 × 101 1.1 × 103 9.0 × 10−1 2.4 × 101 6.3 × 10−4 1.7 × 10−2 Tc-99m 1.0 × 101 2.7 × 102 4.0 1.1 × 102 1.9 × 105 5.3 × 106 Te-121 Tellurium (52) 2.0 5.4 × 101 2.0 5.4 × 101 2.4 × 103 6.4 × 104 Te-121m 5.0 1.4 × 102 3.0 8.1 × 101 2.6 × 102 7.0 × 103 Te-123m 8.0 2.2 × 102 1.0 2.7 × 101 3.3 × 102 8.9 × 103 Te-125m 2.0 × 101 5.4 × 102 9.0 × 10−1 2.4 × 101 6.7 × 102 1.8 × 104 Te-127 2.0 × 101 5.4 × 102 7.0 × 10−1 1.9 × 101 9.8 × 104 2.6 × 106 Te-127m (a) 2.0 × 101 5.4 × 102 5.0 × 10−1 1.4 × 101 3.5 × 102 9.4 × 103 Te-129 7.0 × 10−1 1.9 × 101 6.0 × 10−1 1.6 × 101 7.7 × 105 2.1 × 107 Te-129m (a) 8.0 × 10−1 2.2 × 101

4.0 × 10−1 1.1 × 101 1.1 × 103 3.0 × 104 Te-131m (a) 7.0 × 10−1 1.9 × 101 5.0 × 10−1 1.4 × 101 3.0 × 104 8.0 × 105 Te-132 (a) 5.0 × 10−1 1.4 × 101 4.0 × 10−1 1.1 × 101 1.1 × 104 3.0 × 105 Th-227 Thorium (90) 1.0 × 101 2.7 × 102 5.0 × 10−3 1.4 × 10−1 1.1 × 103 3.1 × 104 Th-228 (a) 5.0 × 10−1 1.4 × 101 1.0 × 10−3 2.7 × 10−2 3.0 × 101 8.2 × 102 Th-229 5.0 1.4 × 102 5.0 × 10−4 1.4 × 10−2 7.9 × 10−3 2.1 × 10−1 Th-230 1.0 × 101 2.7 × 102 1.0 × 10−3 2.7 × 10−2 7.6 × 10−4 2.1 × 10−2 Th-231 4.0 × 101 1.1 × 103 2.0 × 10−2 5.4 × 10−1 2.0 × 104 5.3 × 105 Th-232 Unlimited Unlimited Unlimited Unlimited 4.0 × 10−9 1.1 × 10−7 Th-234 (a) 3.0 × 10−1 8.1 3.0 × 10−1 8.1 8.6 × 102 2.3 × 104 Th(nat) Unlimited Unlimited

Unlimited Unlimited 8.1 × 10−9 2.2 × 10−7 Ti-44 (a) Titanium (22) 5.0 × 10−1 1.4 × 101 4.0 × 10−1 1.1 × 101 6.4 1.7 × 102 Tl-200 Thallium (81) 9.0 × 10−1 2.4 × 101 9.0 × 10−1 2.4 × 101 2.2 × 104 6.0 × 105 Tl-201 1.0 × 101 2.7 × 102 4.0 1.1 × 102 7.9 × 103 2.1 × 105 Tl-202 2.0 5.4 × 101 2.0 5.4 × 101 2.0 × 103 5.3 × 104 Tl-204 1.0 × 101 2.7 × 102 7.0 × 10−1 1.9 × 101 1.7 × 101 4.6 × 102 Tm-167 Thulium (69) 7.0 1.9 × 102 8.0 × 10−1 2.2 × 101 3.1 × 103 8.5 × 104 Tm-170 3.0 8.1 × 101 6.0 × 10−1 1.6 × 101 2.2 × 102 6.0 × 103 Tm-171 4.0 × 101 1.1 × 103 4.0 × 101 1.1 × 103 4.0 × 101 1.1 × 103 U-230 (fast lung absorption) (a)(d) Uranium (92) 4.0 × 101 1.1 × 103 1.0 × 10−1 2.7 1.0 × 103 2.7 × 104 U-230 (medium lung absorption) (a)(e)

4.0 × 101 1.1 × 103 4.0 × 10−3 1.1 × 10−1 1.0 × 103 2.7 × 104 U-230 (slow lung absorption) (a)(f) 3.0 × 101 8.1 × 102 3.0 × 10−3 8.1 × 10−2 1.0 × 103 2.7 × 104 U-232 (fast lung absorption) (d) 4.0 × 101 1.1 × 103 1.0 × 10−2 2.7 × 10−1 8.3 × 10−1 2.2 × 101 U-232 (medium lung absorption) (e) 4.0 × 101 1.1 × 103 7.0 × 10−3 1.9 × 10−1 8.3 × 10−1 2.2 × 101 U-232 (slow lung absorption) (f) 1.0 × 101 2.7 × 102 1.0 × 10−3 2.7 × 10−2 8.3 × 10−1 2.2 × 101 U-233 (fast lung absorption) (d) 4.0 × 101 1.1 × 103 9.0 × 10−2 2.4 3.6 × 10−4 9.7 × 10−3 U-233 (medium lung absorption) (e) 4.0 × 101 1.1 × 103 2.0 × 10−2 5.4 × 10−1 3.6 × 10−4 9.7 × 10−3 U-233 (slow lung absorption) (f) 4.0 × 101 1.1 × 103 6.0 × 10−3 1.6 × 10−1 3.6 × 10−4 9.7 × 10−3 U-234 (fast lung absorption) (d) 4.0 × 101 1.1 × 103 9.0

× 10−2 2.4 2.3 × 10−4 6.2 × 10−3 U-234 (medium lung absorption) (e) 4.0 × 101 1.1 × 103 2.0 × 10−2 5.4 × 10−1 2.3 × 10−4 6.2 × 10−3 U-234 (slow lung absorption) (f) 4.0 × 101 1.1 × 103 6.0 × 10−3 1.6 × 10−1 2.3 × 10−4 6.2 × 10−3 U-235 (all lung absorption types) (a),(d),(e),(f) Unlimited Unlimited Unlimited Unlimited 8.0 × 10−8 2.2 × 10−6 U-236 (fast lung absorption) (d) Unlimited Unlimited Unlimited Unlimited 2.4 × 10−6 6.5 × 10−5 U-236 (medium lung absorption) (e) 4.0 × 101 1.1 × 103 2.0 × 10−2 5.4 × 10−1 2.4 × 10−6 6.5 × 10−5 U-236 (slow lung absorption) (f) 4.0 × 101 1.1 × 103 6.0 × 10−3 1.6 × 10−1 2.4 × 10−6 6.5 × 10−5 U-238 (all lung absorption types) (d),(e),(f) Unlimited Unlimited Unlimited Unlimited 1.2 × 10−8 3.4 × 10−7 U (nat) Unlimited Unlimited Unlimited Unlimited 2.6 × 10−8 7.1 × 10−7 U (enriched to 20% or less)(g) Unlimited Unlimited Unlimited Unlimited see § 173.434 see § 173.434 U (dep) Unlimited

Unlimited Unlimited Unlimited see § 173.434 see § 173.434 V-48 Vanadium (23) 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 6.3 × 103 1.7 × 105 V-49 4.0 × 101 1.1 × 103 4.0 × 101 1.1 × 103 3.0 × 102 8.1 × 103 W-178 (a) Tungsten (74) 9.0 2.4 × 102 5.0 1.4 × 102 1.3 × 103 3.4 × 104 W-181 3.0 × 101 8.1 × 102 3.0 × 101 8.1 × 102 2.2 × 102 6.0 × 103 W-185 4.0 × 101 1.1 × 103 8.0 × 10−1 2.2 × 101 3.5 × 102 9.4 × 103 W-187 2.0 5.4 × 101 6.0 × 10−1 1.6 × 101 2.6 × 104 7.0 × 105 W-188 (a) 4.0 × 10−1 1.1 × 101 3.0 × 10−1 8.1 3.7 × 102 1.0 × 104 Xe-122 (a) Xenon (54) 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 4.8 × 104 1.3 × 106 Xe-123 2.0 5.4 × 101 7.0 × 10−1 1.9 × 101 4.4 × 105 1.2 × 107 Xe-127 4.0 1.1 × 102 2.0 5.4

× 101 1.0 × 103 2.8 × 104 Xe-131m 4.0 × 101 1.1 × 103 4.0 × 101 1.1 × 103 3.1 × 103 8.4 × 104 Xe-133 2.0 × 101 5.4 × 102 1.0 × 101 2.7 × 102 6.9 × 103 1.9 × 105 Xe-135 3.0 8.1 × 101 2.0 5.4 × 101 9.5 × 104 2.6 × 106 Y-87 (a) Yttrium (39) 1.0 2.7 × 101 1.0 2.7 × 101 1.7 × 104 4.5 × 105 Y-88 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 5.2 × 102 1.4 × 104 Y-90 3.0 × 10−1 8.1 3.0 × 10−1 8.1 2.0 × 104 5.4 × 105 Y-91 6.0 × 10−1 1.6 × 101 6.0 × 10−1 1.6 × 101 9.1 × 102 2.5 × 104 Y-91m 2.0 5.4 × 101 2.0 5.4 × 101 1.5 × 106 4.2 × 107 Y-92 2.0 × 10−1 5.4 2.0 × 10−1 5.4 3.6 × 105 9.6 × 106 Y-93 3.0 × 10−1 8.1 3.0 × 10−1 8.1 1.2 × 105 3.3 × 106 Yb-169 Ytterbium (70

) 4.0 1.1 × 102 1.0 2.7 × 101 8.9 × 102 2.4 × 104 Yb-175 3.0 × 101 8.1 × 102 9.0 × 10−1 2.4 × 101 6.6 × 103 1.8 × 105 Zn-65 Zinc (30) 2.0 5.4 × 101 2.0 5.4 × 101 3.0 × 102 8.2 × 103 Zn-69 3.0 8.1 × 101 6.0 × 10−1 1.6 × 101 1.8 × 106 4.9 × 107 Zn-69m (a) 3.0 8.1 × 101 6.0 × 10−1 1.6 × 101 1.2 × 105 3.3 × 106 Zr-88 Zirconium (40) 3.0 8.1 × 101 3.0 8.1 × 101 6.6 × 102 1.8 × 104 Zr-93 Unlimited Unlimited Unlimited Unlimited 9.3 × 10−5 2.5 × 10−3 Zr-95 (a) 2.0 5.4 × 101 8.0 × 10−1 2.2 × 101 7.9 × 102 2.1 × 104 Zr-97 (a) 4.0 × 10−1 1.1 × 101 4.0 × 10−1 1.1 × 101 7.1 × 104 1.9 × 106 a A1 and/or A2 values for these parent radionuclides include contributions from daughter nuclides with half-lives less than 10 days as listed in footnote (a) to Table 2 in the “IAEA Regulations for the Safe Transport of Radioactive Material, SSR-6” (IBR, see § 171.7 of this subchapter). b

The values of A1 and A2 in curies (Ci) are approximate and for information only; the regulatory standard units are Terabecquerels (TBq), (see § 171.10). c The activity of Ir-192 in special form may be determined from a measurement of the rate of decay or a measurement of the radiation level at a prescribed distance from the source. 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. h [Reserved] i A2 = 0.74 TBq (20 Ci) for Mo-99 for domestic use.

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