GE Senographe DS Manual page 1707

GE Healthcare Senographe DS
Revision 1 Service Information and Procedures Class A 2385072-16-8EN
Job Card CAL A046 - Half-Value Layer Measurement
8-2 Information:
The Senographe automatically computes the HVL by interpolation using the following formula:
/ ) − 0.2 ∗ (2 / )
0.5 * ln(2 E E ln E E
=
0.2 0 0.5 0
HVL
Ε ( / Ε )
ln
0.2 0.5
the units are mm of Al)
(
Where E , E , E , are dose values measured behind 0, 0.2 mm and 0.5 mm aluminum respectively.
0 0.2 0.5
The Senographe calculates Tube Yield as E / mAs (unit: mGy/mAs) for this technique.
0
9 COMPLETION
If you are handing the machine back to the user at this point, switch the Senographe off, then on again.
Page no. 1707 Chapter 9
JC-CAL-A-046.fm