10 CFR Appendix E
Values for Establishing Sealed Radioactive Source Accountability and Radioactive Material Posting and Labeling Requirements
June 9, 2020
CFR

The data presented in appendix E are to be used for identifying accountable sealed radioactive sources and radioactive material areas as those terms are defined at §835.2(a), establishing the need for radioactive material area posting in accordance with §835.603(g), and establishing the need for radioactive material labeling in accordance with §835.605.

Open Table
Nuclide Activity (µCi)
H-3 1.5E + 08
Be-7 3.1E + 03
Be-10 1.4E + 05
C-14 4.6E + 06
Na-22 1.9E + 01
Al-26 1.5E + 01
Si-32 4.9E + 04
S-35 2.4E + 06
Cl-36 5.2E + 05
K-40 2.7E + 02
Ca-41 9.3E + 06
Ca-45 1.1E + 06
Sc-46 6.2E + 01
Ti-44 1.5E + 02
V-49 1.0E + 08
Mn-53 7.5E + 07
Mn-54 6.5E + 01
Fe-55 2.9E + 06
Fe-59 1.9E + 02
Fe-60 8.1E + 03
Co-56 3.9E + 01
Co-57 2.3E + 02
Co-58 1.3E + 02
Co-60 1.7E + 01
Ni-59 3.2E + 06
Ni-63 1.3E + 06
Zn-65 1.1E + 02
Ge-68 5.6E + 02
As-73 5.3E + 02
Se-75 6.3E + 01
Se-79 8.7E + 05
Rb-83 9.1E + 01
Rb-84 2.0E + 02
Sr-85 1.2E + 02
Sr-89 4.8E + 05
Sr-90 3.5E + 04
Y-88 3.3E + 01
Y-91 5.0E + 04
Zr-88 1.1E + 02
Zr-93 9.3E + 04
Zr-95 1.9E + 02
Nb-91 6.9E + 01
Nb-91m 3.6E + 02
Nb-92 1.8E + 01
Nb-93m 4.4E + 02
Nb-94 2.3E + 01
Nb-95 3.4E + 02
Mo-93 7.7E + 01
Tc-95m 1.3E + 02
Tc-97 8.1E + 01
Tc-97m 3.5E + 02
Tc-98 2.5E + 01
Tc-99 8.4E + 05
Ru-103 4.4E + 02
Ru-106 2.5E + 02
Rh-101 8.7E + 05
Rh-102 6.4E+05
Rh-102m 3.0E+05
Pd-107 9.3E + 06
Ag-105 3.3E + 06
Ag-108m 1.8E + 01
Ag-110m 2.2E + 01
Cd-109 1.6E + 02
Cd-113m 2.0E + 04
Cd-115m 1.0E + 04
In-114m 7.7E + 02
Sn-113 3.1E + 02
Sn-119m 3.3E + 02
Sn-121m 8.1E + 05
Sn-123 1.3E + 04
Sn-126 1.8E + 02
Sb-124 9.1E + 01
Sb-125 6.7E + 01
Te-121m 1.8E + 02
Te-123m 2.8E + 02
Te-125m 4.4E + 02
Te-127m 8.0E + 02
Te-129m 2.3E + 03
I-125 3.5E + 02
I-129 1.8E + 02
Cs-134 2.6E + 01
Cs-135 1.3E + 06
Cs-137 6.0E + 01
Ba-133 5.1E + 01
La-137 2.7E + 05
Ce-139 2.4E + 02
Ce-141 2.4E + 03
Ce-144 1.4E + 03
Pm-143 1.3E + 02
Pm-144 2.9E + 01
Pm-145 2.6E + 02
Pm-146 4.4E + 01
Pm-147 7.7E + 05
Pm-148m 1.0E + 02
Sm-145 2.4E + 06
Sm-146 4.0E + 02
Sm-151 2.5E + 05
Eu-148 1.1E + 06
Eu-149 1.1E + 07
Eu-152 3.1E + 01
Eu-154 3.1E + 01
Eu-155 3.6E + 02
Gd-146 5.1E + 05
Gd-148 9.0E + 01
Gd-151 2.9E + 06
Gd-153 2.1E + 02
Tb-157 2.5E + 03
Tb-158 9.0E + 04
Tb-160 1.2E + 02
Dy-159 1.0E + 07
Ho-166m 2.1E + 01
Tm-170 8.4E + 03
Tm-171 2.8E + 04
Yb-169 5.5E + 02
Lu-173 1.8E + 06
Lu-174 9.3E + 05
Lu-174m 1.0E + 06
Lu-177m 5.8E + 01
Hf-172 7.3E + 04
Hf-175 3.0E + 06
Hf-178m 8.7E + 03
Hf-181 3.4E + 02
Hf-182 7.5E + 03
Ta-179 9.3E + 06
Ta-182 7.3E + 01
W-181 1.0E + 03
W-185 3.9E + 06
W-188 6.3E + 04
Re-183 5.3E + 02
Re-184 2.6E + 02
Re-184m 1.5E + 02
Re-186m 3.4E + 05
Os-185 1.3E + 02
Os-194 6.4E + 04
Ir-192 1.3E + 02
Ir-192m 1.4E + 05
Ir-194m 2.7E + 01
Pt-193 8.7E + 07
Au-195 4.8E + 02
Hg-194 5.2E + 04
Hg-203 4.9E + 02
Tl-204 2.2E + 04
Pb-202 1.9E + 05
Pb-205 9.0E + 01
Pb-210 9.2E + 01
Bi-207 1.7E + 01
Bi-208 1.5E + 01
Bi-210m 1.2E + 03
Po-209 6.3E + 03
Po-210 1.2E + 03
Ra-226 2.2E + 02
Ra-228 1.5E + 03
Ac-227 4.2E + 00
Th-228 8.4E + 01
Th-229 3.1E + 01
Th-230 5.4E + 00
Th-232 9.3E + 01
Pa-231 3.0E + 01
U-232 1.0E + 02
U-233 3.9E + 02
U-234 2.9E + 02
U-235 6.7E + 01
U-236 3.1E + 02
U-238 3.5E + 02
Np-235 1.1E + 02
Np-236 2.1E + 01
Np-237 4.9E + 01
Pu-236 2.0E + 02
Pu-237 3.3E + 02
Pu-238 9.0E + 01
Pu-239 8.4E + 01
Pu-240 8.4E + 01
Pu-241 4.6E + 03
Pu-242 8.7E + 01
Pu-244 9.0E + 01
Am-241 7.2E + 01
Am-242m 1.1E + 02
Am-243 7.3E + 01
Cm-241 1.0E + 05
Cm-242 6.2E + 02
Cm-243 4.8E + 01
Cm-244 1.5E + 02
Cm-245 5.0E + 01
Cm-246 1.0E + 02
Cm-247 8.5E + 01
Cm-248 2.8E + 01
Cm-250 5.4E + 00
Bk-247 6.0E + 01
Bk-249 2.7E + 04
Cf-248 4.4E + 02
Cf-249 5.5E + 01
Cf-250 1.2E + 02
Cf-251 5.3E + 01
Cf-252 5.2E + 00
Cf-254 1.2E + 02
Es-254 6.3E + 01
Es-255 8.8E + 03
Fm-257 5.1E + 02
Md-258 6.1E + 02

Any alpha emitting radionuclide not listed in appendix E and mixtures of alpha emitters of unknown composition have a value of 10 µCi.

With the exception that any type of STC has a value of 10 Ci, any radionuclide other than alpha emitting radionuclides not listed in appendix E and mixtures of beta emitters of unknown composition have a value of 100 µCi.

Note: Where there is involved a mixture of radionuclides in known amounts, derive the value for the mixture as follows: determine, for each radionuclide in the mixture, the ratio between the quantity present in the mixture and the value otherwise established for the specific radionuclide when not in the mixture. If the sum of such ratios for all radionuclides in the mixture exceeds unity (1), then the accountability criterion has been exceeded.

[72 FR 31940, June 8, 2007, as amended at 82 FR 37514, Aug. 11, 2017]


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