Reproducibility Test (Usa Only) - Siemens MOBILETT XP Digital Maintenance Instruction

Inspection and maintenance
3.8

Reproducibility test (USA only)

Requirement:
The coefficient of variation for the radiation dose for any combination of exposure param-
eters does not exceed 0.045. This requires operation at the line voltage compliant with
Siemens specifications.
NOTE
Required measuring instrument:
- Dosimeter
Procedure:
•
After switching the system on, wait until its temperature has stabilized. The unit is ready
for these measurements after 15 minutes.
•
X
Initiate the number of exposures with the specified exposure data:
- 85 kV, 1.0 mAs, 10 exposures.
•
Measure the dose for each exposure.
•
Reset the display prior to each new measurement.
Calculations:Coefficient of variation C
Coefficient of variation C is determined for a series of 10 dose measurements with the fol-
lowing formula:
Fig. 31:
s
_
x
x
i
n
Siemens AG
Medical Solutions
In the following test, 10 sequential exposures are taken within one
hour.
The exposure parameters should be briefly set to different values
following each measurement.
= Standard deviation resulting from the measurements
= Average measurement of the series
= i. measurement of series
= Number of individual measurements in series
SPR8-230.831.30.03.02
11.05
MOBILETT XP Digital
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