Topics covered in this article include:

Set Linac Specific Factors
Create the Electrometer and Set Factor
Create the Ion Chamber and Set Factors
Add TG-51 Schedule
Set Schedule Settings
- Photon Schedule Settings
- Electron Schedule Settings

Set Linac Specific Factors

Navigate to Manage Sites & Machines then click the Edit link to the right of the desired linac. Select either SSD or SSD under Photons (Electrons can only be set to SSD):

If the Photon Beam Factors are set to SSD, enter the SSD, depth, and field size. Select each photon energy that will be used. For each selected energy enter the Clinical %dd(depth)and optionally an expiration date. The Clinical %dd(depth) should be entered as a percentage (e.g., 66.3).

If the Photon Beam Factors are set to SAD, enter the SAD, depth, and field size. Select each photon energy that will be used. For each selected energy enter the Clinical TMR _{(depth, field size)}and optionally an expiration date. The Clinical TMR _{(depth, field size)}should be entered as a proportion (e.g., 0.778).

Under Electron Beam Factors, set the SSD and cone size. Use the R₅₀ Entry drop-down to select either "Calculate from I₅₀" or "Enter R₅₀". Select each electron energy that will be used. For each selected energy enter either I₅₀ or R₅₀, the PDD (d_ref, cone size), and optionally an expiration date:

For the calculation of R50 values from I50 values, please see this section in the Background and Calculation Notes help article.

If desired any documentation for the factors can be added using the Attach a document button.

Create the Electrometer and Set Factor

Navigate to Manage Measurement Devices. Click the Add device button. Select Electrometer for device type, enter a unique name for the Device label, select the site (recommended), select Active for the Status and complete any additional fields desired. Click the Sign and Update device button to save the new device.

On the Manage Measurement Devices page, click the Calibration link next to the newly created electrometer. On the Calibrations Factors for Measurement Device page, click the Update Equipment Calibration button.

On the Update Calibration Factors page, enter a settings note, the P_elec value, the calibration date, and the expiration date. Calibration documents can also be added. Complete the setup by clicking the Sign and Update calibration button.

Optionally multiple voltage settings may be added by choosing the Add Setting button on the Update Calibrations Factors Page. Enter a settings note, the P_elec value, the calibration date, and the expiration date. Complete the setup by clicking the Sign and Update calibration button.

Create the Ion Chamber and Set Factors

Navigate to Manage Measurement Devices. Click the Add device button. Enter a unique name for the Device label, select the site (recommended), select Active for the Status, select Ion Chamber for the Device Type, and select Yes for "Used for TG-51?". Select the correct chamber from the Chamber Type drop down. If the desired type is not available, select "Create your own", enter the Cavity Radius and k_ecal at a minimum. Complete any of the remaining optional fields as desired.

On the Manage Measurement Devices page, click the Calibration link next to the newly created ion chamber. On the Calibrations Factors for Measurement Device page, click the Update Equipment Calibration button.

Enter the N^60_Co_D,wfactor for the chamber, the calibration date, and the expiration date:

Complete the setting the equipment calibration factors by clicking the Sign and Update calibration button.

Next set the machine calibration factors by clicking the + Add Machine Calibration button.

Enter the k_Q factors (photons), k'_R50 factors (electrons), and optionally add an expiration date for each. Alternatively the k_Q or k'_R50 factors can be calculated automatically. The k_Q automated calculation will open up dialogue so that the proper k_Q calculation can be used. See the Background and Calculation Notes help page for the details on the calculation.

Complete setting the machine calibration factors by clicking the Sign and Update calibration button.

Add TG-51 Schedule

Navigate to Manage Schedule Configurations and use the + Add QA schedule link under the desired machine to add a schedule. Select either the photon or the electron TG-51 templates:

Note that the photon worksheet template will only be available as SAD setup or SSD setup depending on the linac specific factors were set. Complete the remaining items in the schedule as desired.

Set Schedule Settings

Navigate to Manage Schedule Configurations, hover over the desired TG-51 schedule, and click the gear icon to enter the Schedule settings. Click the Edit Schedule settings button. Any field that is left blank can be entered when the worksheet is completed under the Schedules page. The following presets apply to both photon and electron worksheets:

Collimator Angle is the collimator angle used when collecting measurements.
#MUs is the number of monitor units used.
Raw Fields is the number of measurements shown on the worksheet. When averaging measurements, empty fields will be ignored.

Photon Schedule Settings

P_rp is used to factor for FFF energies and should be left blank so that it can be completed at the time of the worksheet if FFF energies are used.

The Voltage Actual fields should typically be left blank and completed when filling out the worksheet.

The Voltage Settings should be set following one of the two patterns below:

Row	Pattern 1	Pattern 2
1	Vh+	Vh-
2	Vl+	Vl-
3	Vl-	Vl+

Both patterns must obey the following rules:

Row 2 must have the same sign as row 1
The absolute value of row 2 must be less than or equal to the absolute value of row 1
Row 3 must be the opposite sign of row 1
The absolute value of row 3 must be within 5 volts of the absolute value of row 1

The adjustment voltage should be the same sign as row 1.

Electron Schedule Settings