OEC 9800 Periodic Maintenance Procedure
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11. Adjust the technique to 40 kVp @ 5 mA and take an exposure.
Note
:
Allow the readings on the dosimeter to stabilize for a few moments.
12. Read the dose rate on the Dosimeter, divide it by the mA (5 mA) and enter the value calculated into the
corresponding dose rate field.
13. Set the kV and mA to each of the following techniques and take an X-ray. Read the Dosimeter for each X-ray shot,
divide it by the mA value and enter the value calculated into the Dose Rate field that corresponds to the kV and
mA field.
•
50 kVp @ 5 mA
•
60 kVp @ 4 mA
•
80 kVp @ 3 mA
•
100 kVp @ 2 mA
•
120 kVp @ 2 mA
14. Once you have entered all six Dosimeter readings press the Calculate Coefficients command button.
15. The A, B, and C coefficients will be calculated and displayed in their respective fields.
16. Click on the File pulldown menu and click on Download DAP Data. This will download the DAP calibration data to
the 9800 system.
17. If the system has 1 collimator leaf perform the procedure to Calculate Constants.
18. Archive the DAP calibration data to disk by selecting the File pulldown menu and clicking on Save DAP Calibration
File As. Specify the drive letter and path.
Calculate Rotation Calibration Constants
The Dose Area Product (DAP) calculation is affected by the number of collimator leaves. It is only necessary to
calculate rotation calibration constants if the collimator has 1 leaf.