Dose Area Product - Siemens ARCADIS Varic Manual

Adjustments

Dose area product

DAP chamber test (Wellhöfer) / DAP chamber adjustment (PTW)
1. Decide which DAP chamber is installed, "Wellhöfer" or "PTW", see path <Main Sys-
tem>-<Configuration>-<Options>.
2. Continue with the corresponding description "Wellhöfer..." or "PTW...".
NOTE
Wellhöfer - chamber gain adjustment
1. Register an emergency patient to allow radiation release.
2. Select dose rate for air kerma or dose for DAP, depending on the configuration, at the
external dose meter.
NOTE
3. Attach the small dose measurement chamber (1cm
4. Select I.I. full format and open the collimator X-iris and the slot diaphragm to the maxi-
mum position.
5. Select the following exam set to get as a result the HC2 control curve:
X
6. Briefly release fluoro, select the <kV STOP> key and 70 kV with the kV + / - buttons on
the console.
X
7. Release fluoro and compare the dose rate from the external dose meter to the internal
monitor display.
Siemens AG
Medical Solutions
DAP camber resolution 0.01cGy cm*cm = "Wellhöfer" DAP
DAP camber resolution 1.0 cGy cm*cm = "PTW" DAP
A chamber gain adjustment is necessary if the DAP accuracy
check or the air kerma accuracy check is not in tolerance.
Make sure that 2.5mm AL filtration at the external dose meter is
selected during the chamber gain adjustment.
Ortho/Trauma; Standard; Body reg = HIP; Fluoroscopy
Use correction factors and calculations described under "DAP accuracy check" or
under "Air kerma accuracy check".
Calculate the external dose meter's deviation from the internal monitor dis-
play.Difference = [(int. value) - (ext value)] / (ext value)
The maximum allowed difference is ± 0.25 (± 25%).
SPR2-310.842.01.07.02
12.06
3
) into the center of the I. I. grid.
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ARCADIS Varic / Orbic