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Risk Assessment

CPM Calculator

Using the CPM Calculator

Click on the steps below for detailed instructions about each page of the CPM Calculator.

1. Select Radionuclides and Decay Method
2. Activity Concentrations
3. Detector & Site Information
4. Results

1. Select Radionuclides and Decay Method

Select primary (parent) radionuclides of interest by clicking on a radionuclide in either the "Complete List" or the "Common Radionuclides" column to highlight it and then click on the ">>" button to add it to the "Selected" column. Then select the decay method that was used to generate the Target Activity Concentrations (TACs). Click "Next (new tab)". If multiple radionuclides are selected, Field Activity Concentrations (FACs) will be required in step 2.

I have consulted with EPA Headquarters as set forth in the User Guide and Home Page.

Complete List		Selected

Common Radionuclides

Select Decay Method

Assumes period of peak risk (requires peak risk Target Activity Concentrations (TACs) calculated from option 1 of the PRG/DCC tool) Assumes secular equilibrium (requires secular equilibrium TACs calculated from option 2 of the PRG/DCC tool) Does not assume secular equilibrium, includes progeny throughout chain (requires TACs for all chain members calculated from option 3 of the PRG/DCC tool) Does not assume secular equilibrium, includes selected isotopes only (requires parent-only TACs calculated from option 4 of the PRG/DCC tool)

US EPA

Risk Assessment

CPM Calculator

Using the CPM Calculator

1. Select Radionuclides and Decay Method

2. Activity Concentrations

3. Detector Specifications

4. Results

Select Decay Method

Ac-223
Ac-224
Ac-225
Ac-226
Ac-227
Ac-228
Ag-102
Ag-103
Ag-104
Ag-104m
Ag-105
Ag-106
Ag-106m
Ag-108
Ag-108m
Ag-109m
Ag-110
Ag-110m
Ag-111
Ag-112
Ag-115
Al-26
Al-28
Am-237
Am-238
Am-239
Am-240
Am-241
Am-242
Am-242m
Am-243
Am-244
Am-244m
Am-245
Am-246
Am-246m
As-69
As-70
As-71
As-72
As-73
As-74
As-76
As-77
As-78
At-207
At-211
At-215
At-216
At-217
Au-193
Au-194
Au-195
Au-195m
Au-198
Au-198m
Au-199
Au-200
Au-200m
Au-201
Ba-126
Ba-128
Ba-131
Ba-131m
Ba-133
Ba-133m
Ba-135m
Ba-137m
Ba-139
Ba-140
Ba-141
Ba-142
Be-7
Bi-200
Bi-201
Bi-202
Bi-203
Bi-205
Bi-206
Bi-207
Bi-210
Bi-210m
Bi-211
Bi-212
Bi-213
Bi-214
Bk-245
Bk-246
Bk-247
Bk-249
Bk-250
Br-74
Br-74m
Br-75
Br-76
Br-77
Br-80
Br-80m
Br-82
Br-83
Br-84
C-11
Ca-45
Ca-47
Ca-49
Cd-104
Cd-107
Cd-109
Cd-113m
Cd-115
Cd-115m
Cd-117
Cd-117m
Ce-134
Ce-135
Ce-137
Ce-137m
Ce-139
Ce-141
Ce-143
Ce-144
Cf-244
Cf-246
Cf-248
Cf-249
Cf-250
Cf-251
Cf-252
Cf-253
Cf-254
Cl-36
Cl-38
Cl-39
Cm-238
Cm-240
Cm-241
Cm-242
Cm-243
Cm-244
Cm-245
Cm-246
Cm-247
Cm-248
Cm-249
Cm-250
Co-55
Co-56
Co-57
Co-58
Co-58m
Co-60
Co-60m
Co-61
Co-62m
Cr-48
Cr-49
Cr-51
Cs-125
Cs-126
Cs-127
Cs-128
Cs-129
Cs-130
Cs-131
Cs-132
Cs-134
Cs-134m
Cs-135m
Cs-136
Cs-137
Cs-138
Cu-60
Cu-61
Cu-62
Cu-64
Cu-66
Cu-67
Dy-155
Dy-157
Dy-159
Dy-165
Dy-166
Er-161
Er-165
Er-169
Er-171
Er-172
Es-250
Es-251
Es-253
Es-254
Es-254m
Eu-145
Eu-146
Eu-147
Eu-148
Eu-149
Eu-150
Eu-150m
Eu-152
Eu-152m
Eu-154
Eu-155
Eu-156
Eu-157
Eu-158
F-18
Fe-52
Fe-55
Fe-59
Fm-252
Fm-253
Fm-254
Fm-255
Fm-257
Fr-219
Fr-220
Fr-221
Fr-222
Fr-223
Ga-65
Ga-66
Ga-67
Ga-68
Ga-70
Ga-72
Ga-73
Gd-145
Gd-146
Gd-147
Gd-149
Gd-151
Gd-153
Gd-159
Ge-66
Ge-67
Ge-68
Ge-69
Ge-71
Ge-75
Ge-77
Ge-78
Hf-170
Hf-172
Hf-173
Hf-175
Hf-177m
Hf-178m
Hf-179m
Hf-180m
Hf-181
Hf-182
Hf-182m
Hf-183
Hf-184
Hg-194
Ho-155
Ho-157
Ho-159
Ho-161
Ho-162
Ho-162m
Ho-164
Ho-164m
Ho-166
Ho-166m
Ho-167
I-122
In-109
In-110
In-110m
In-111
In-112
In-113m
In-114
In-114m
In-115m
In-116m
In-117
In-117m
In-119
In-119m
Ir-182
Ir-184
Ir-185
Ir-186
Ir-186m
Ir-187
Ir-188
Ir-189
Ir-190
Ir-190m
Ir-190n
Ir-191m
Ir-192
Ir-192m
Ir-194
Ir-194m
Ir-195
Ir-195m
K-38
K-40
K-42
K-43
K-44
K-45
La-131
La-132
La-134
La-135
La-137
La-138
La-140
La-141
La-142
La-143
Lu-169
Lu-170
Lu-171
Lu-172
Lu-173
Lu-174
Lu-174m
Lu-176
Lu-176m
Lu-177
Lu-177m
Lu-178
Lu-178m
Lu-179
Mg-28
Mn-51
Mn-52
Mn-52m
Mn-54
Mn-56
Mo-101
Mo-90
Mo-93
Mo-93m
Mo-99
N-13
Na-22
Na-24
Nb-88
Nb-89
Nb-89m
Nb-90
Nb-93m
Nb-94
Nb-95
Nb-95m
Nb-96
Nb-97
Nd-136
Nd-138
Nd-139
Nd-139m
Nd-141
Nd-141m
Nd-147
Nd-149
Nd-151
Ni-57
Np-232
Np-233
Np-234
Np-235
Np-236
Np-236m
Np-237
Np-238
Np-239
Np-240
Np-240m
O-15
Os-180
Os-181
Os-182
Os-185
Os-189m
Os-190m
Os-191
Os-191m
Os-193
Os-194
P-30
Pa-227
Pa-228
Pa-230
Pa-231
Pa-232
Pa-233
Pa-234
Pa-234m
Pb-195m
Pb-198
Pb-199
Pb-200
Pb-201
Pb-202
Pb-202m
Pb-203
Pb-205
Pb-210
Pb-211
Pb-212
Pb-214
Pd-100
Pd-101
Pd-103
Pd-109
Pm-141
Pm-142
Pm-143
Pm-144
Pm-145
Pm-146
Pm-147
Pm-148
Pm-148m
Pm-149
Pm-150
Pm-151
Po-203
Po-205
Po-207
Po-210
Po-211
Po-213
Po-214
Po-215
Po-216
Pr-136
Pr-137
Pr-138
Pr-138m
Pr-139
Pr-142
Pr-143
Pr-144
Pr-144m
Pr-145
Pr-147
Pt-186
Pt-188
Pt-189
Pt-191
Pt-193
Pt-193m
Pt-195m
Pt-197
Pt-197m
Pt-199
Pt-200
Pu-234
Pu-235
Pu-236
Pu-237
Pu-238
Pu-239
Pu-240
Pu-241
Pu-242
Pu-243
Pu-244
Pu-245
Pu-246
Ra-222
Ra-223
Ra-224
Ra-225
Ra-226
Ra-227
Ra-228
Rb-79
Rb-80
Rb-81
Rb-81m
Rb-82
Rb-82m
Rb-83
Rb-84
Rb-86
Rb-88
Rb-89
Re-178
Re-180
Re-181
Re-182
Re-182m
Re-184
Re-184m
Re-186
Re-186m
Re-188
Re-188m
Re-189
Rh-100
Rh-101
Rh-101m
Rh-102
Rh-102m
Rh-103m
Rh-105
Rh-106
Rh-106m
Rh-107
Rh-99
Rh-99m
Ru-103
Sb-115
Sb-116
Sb-116m
Sb-117
Sb-118m
Sb-119
Sb-120
Sb-120m
Sb-122
Sb-124
Sb-124m
Sb-124n
Sb-125
Sb-126
Sb-126m
Sb-127
Sb-128
Sb-128m
Sb-129
Sb-130
Sb-131
Sc-43
Sc-44
Sc-44m
Sc-46
Sc-47
Sc-48
Sc-49
Se-70
Se-73
Se-73m
Se-75
Se-77m
Se-81
Se-81m
Se-83
Si-31
Sm-141
Sm-141m
Sm-142
Sm-145
Sm-151
Sm-153
Sm-155
Sm-156
Sn-110
Sn-111
Sn-113
Sn-117m
Sn-119m
Sn-121m
Sn-123
Sn-123m
Sn-125
Sn-126
Sn-127
Sn-128
Sr-80
Sr-81
Sr-82
Sr-83
Sr-85
Sr-85m
Sr-87m
Sr-89
Sr-91
Sr-92
Ta-172
Ta-173
Ta-174
Ta-175
Ta-176
Ta-177
Ta-178
Ta-178m
Ta-179
Ta-180
Ta-182
Ta-182m
Ta-183
Ta-184
Ta-185
Ta-186
Tb-147
Tb-149
Tb-150
Tb-151
Tb-153
Tb-154
Tb-155
Tb-156
Tb-156m
Tb-156n
Tb-157
Tb-158
Tb-160
Tb-161
Tc-101
Tc-104
Tc-93
Tc-93m
Tc-94
Tc-94m
Tc-95
Tc-95m
Tc-96
Tc-96m
Tc-97
Tc-97m
Tc-98
Tc-99
Tc-99m
Te-116
Te-121m
Te-123m
Te-125m
Te-127
Te-127m
Te-129m
Th-226
Th-227
Th-228
Th-229
Th-230
Th-231
Th-232
Th-234
Ti-44
Ti-45
Tl-194
Tl-194m
Tl-195
Tl-197
Tl-198
Tl-198m
Tl-199
Tl-200
Tl-201
Tl-202
Tl-204
Tl-206
Tl-207
Tl-208
Tl-209
Tm-162
Tm-166
Tm-167
Tm-170
Tm-171
Tm-172
Tm-173
Tm-175
U-230
U-231
U-232
U-233
U-234
U-235
U-236
U-237
U-238
U-239
U-240
V-47
V-48
W-177
W-178
W-179
W-181
W-185
W-187
W-188
Y-86
Y-86m
Y-87
Y-88
Y-90
Y-90m
Y-91
Y-91m
Y-92
Y-93
Y-94
Y-95
Yb-162
Yb-166
Yb-167
Yb-169
Yb-175
Yb-177
Yb-178
Zn-62
Zn-63
Zn-65
Zn-69
Zn-69m
Zn-71m
Zn-72
Zr-86
Zr-88
Zr-89
Zr-95
Zr-97

Risk Assessment

CPM Conversion

CPM Calculator

Using the CPM Calculator

1. Select Radionuclides and Decay Method

2. Activity Concentrations

3. Detector Specifications

4. Results

Select Decay Method