NORLAND BONE DENSITOMETRY CALIBRATION FAILED

Hello, has this machine been in use? Usually that error happens when it has been out of use for a while. Try running 10 QC scans and then run the whole QA and QC. It should pass after that.

The correction factor is the offset number used to make the QC result match the phantom value. It is set at the end of the 6 hour primary calibration.

Correction Factors or Drift Errors
During a daily calibration there are many comparison checks.
The correction factor is dividing the current calibration values by the running average of
past calibrations or the initial. If the values are perfectly matched then the correction
value is one. If the difference is too great that means the count rate difference between
the current calibration and the running average is too great.
Drift errors are comparing the current calibration to the initial calibration. The following is
an example of an error message relating to a 2-channel drift error:
''The counts 379800 at plastic 0, metal 0, for filter 6, low energy, have drifted 10.5%
from the reference counts 360,000. The maximum allowable is 10%"
1. Print the C:\XR26\CAL TRACE\Drift.his file (2-channel C:\xR26\CALDRIFT.TRC), by
selecting Xdrift from page 2 of the XSST menu, rev 1.3.1 or higher (2-channel enter
SERVICE, the type XDRIFT). VVhen prompted press any key to display the graph.
After the graph is displayed press P to print.
NOTE: If the message appears "Invalid European data in file" the CALDRIFT.TRC file
must be edited, using any type of DOS editor. This is caused by changing the date
from European to USA in host software Preferences under the Setup menu.
To analyze the graphs refer to the Xdrift Graphs Appendix of this Calibration
Troubleshooting Guide.
2. If the correction factors or drift is not severe a new initial calibration may fix the
problem. However the system should be monitored to verify the failure does not
occur in the near future.
3. Check the PMT spectrum, stability test, and filter tests.

Have you done an initial calibration ?
your problem is surely the filter asssembly .

Thanks everybody i have changed the calib file in C: and make initial calibration now its ok.