A Mammography Dose Evaluation Table

Section 370 Section 370.TABLE A   Mammography Dose Evaluation Table This Table is used to determine the mean glandular dose in milligrays delivered by 25.8 mC/kg (or millirad) delivered by 1 R in air incident on a 4.2 centimeter thickness compressed breast of average density (50 percent adipose and 50 percent glandular tissue).  Values listed are for the first half-value layer (HVL) in millimeters of aluminum (mm Al), for x-ray tube target-filter combinations of molybdenum/molybdenum (Mo/Mo) and tungsten/ aluminum (W/Al). Linear extrapolation or interpolation shall be made for any HVL not listed. Mean Glandular Dose in milligrays for 25.8 mC/kg (or millirad for 1 R) Entrance Exposure for a 4.2 Centimeter Compressed Breast of Average Density HVL Mo/Mo Target-Filter X-Ray Tube Voltage (kVp) W-A1 Target- (mm AL) 23 24 25 26 27 28 29 30 31 32 33 Filter Combination 0.23 116 0.24 121 124 0.25 126 129 131 0.26 130 133 135 138 0.27 135 138 140 142 143 0.28 140 142 144 146 147 149 0.29 144 146 148 150 151 153 154 0.30 149 151 153 155 156 157 158 159 170 0.31 154 156 157 159 160 161 162 163 164 175 0.32 158 160 162 163 164 166 167 168 168 170 171 180 0.33 163 165 166 168 169 170 171 173 173 174 175 185 0.34 168 170 171 172 173 174 175 176 177 178 179 190 0.35 174 175 176 177 178 179 180 181 182 183 194 0.36 179 181 182 183 184 185 185 186 187 199 0.37 185 186 187 188 189 190 191 191 204 0.38 190 191 192 193 194 195 195 208 0.39 196 197 198 198 199 200 213 0.40 201 202 203 204 204 217 0.41 206 207 208 208 221 0.42 211 212 212 225 0.43 215 216 230 0.44 220 234 0.45 238 AGENCY NOTE:  Adapted from:  Mammography Quality Control Manual:  Medical Physicist's Section, Revised Edition, 1999.