biodex ATOMLAB 500, Operation And Service Manual, Page: 85 / 212

Figure 6.20 . A Geometry Test with data.
NOTE: The normalized volume reading is the volume used as the starting point for the
calculations. The calculated activity matches the measured activity for the normalized
volume and is displayed. The correction factor is 1. All future calculated activity uses this
as a start point. The recommended volume to use for the normalized volume is usually
the first volume that is tested.
7. Touch <Accept> when all parameters are set to return to the Geometry Test screen.
8. Touch <Zero Background> to zero the background reading, if necessary. The Background
live reading is displayed next to the first volume.
9. Place the first volume in the detector. The first measured activity reading is displayed in
red. When the measured activity settles, touch <Record Reading> to record the
measured activity reading. The system advances to the second volume.
10. Remove the sample and adjust the volume for the second measured volume. Replace the
source in the detector. When the reading settles, touch <Record Reading>. continue
removing the source from the detector and adjusting the volume until all volume
measurements are completed.
11. Once the normalized volume is counted, the system calculates the activity and correction
factor or variance. As each new volume is recorded, the calculation for that volume is
performed.
NOTE: To stop the test before all volumes are measured, touch <Save> to keep the test
with the volumes already recorded.
NOTE: If any of the correction factors are out of the acceptable range they will be
highlighted in red.
12. After the last reading is completed, touch <Save Data>. The Save Geometry Test Data
screen is displayed.