This article includes the following topics:

•  Conditions and Factors
•  Calculated Dose
•  Adjustments

Conditions and Factors

Only one photon energy for a TG-51 schedule can be completed at a time. Select the energy from the Energy drop-down and then optionally complete "Participating Physicists" and "reason for Calibration" fields.

Select the ion chamber to be used from the "Ion Chamber" drop-down. Only ion chambers that a calibration set for the specific linac will be shown. After selecting the ion chamber, the remaining fields in the table will auto-fill if the fields were completed as part of the ion chamber setup. For any fields that did not auto-fill either check your prior setup or complete them manually.

Select the electrometer to be used from the "Electrometer drop-down. After selecting the electrometer, the remaining fields in the table will auto-fill if the fields were completed as part of the electrometer setup. For any fields that did not auto-fill either check your prior setup or complete them manually.

Under measurement conditions, Depth, SAD, "Field Size X", and "Field Size Y" fields will auto-fill from the linac specific factors if they have been set under Manage Sites and Machines. The "Collimator Angle" and #MUs fields will auto-fill if they have been preset in QA settings. Complete the MU Rate and any missing fields.

The "Beam Quality Factor, k_Q" field will auto-fill from the machine specific ion chamber calibration factors.

Enter the Temperature and Pressure fields. The T_W and P_TP fields will calculate automatically.      

Enter the "Voltage Actual" for each row; typically it is the same as the "Voltage Setting" as set in the QA settings. Enter the Readings measured with polarity. The Avg. field will be automatically calculated from non-empty Readings fields.

The P_pol and P_ion fields will calculate automatically once all rows above have an Avg calculated.

Calculated Dose

If it has not been preset in QA settings, enter the P_rp  and the remaining fields will calculate automatically. If any do not calculate automatically check for any empty fields above. 

Adjustments

If the output needs to be adjusted select Yes from the Adjustments drop-down. Enter the proper value in the "# of MUs" field and the "Target Reading" will calculate automatically. The "Target Reading" is the measurement that would result in a Final Dose of 1.

Enter the "Voltage Actual" for each row; typically it is the same as the "Voltage Setting" as set in the QA settings. Enter the Readings measured with polarity. The Avg. field will be automatically calculated from non-empty Readings fields.

Note that both the "as found" and adjusted (as left) doses will be tracked longitudinally.