9
5 Maintenance
The Inspector
+
requires regular calibration and careful handling to assure good measurements. Use the following
guidelines to maintain the Inspector
+
properly.
Calibration
The Inspector
+
should be calibrated as often as your regulations require, or in any case, at least once a year. The best
way to calibrate is using a calibrated source. If no source is available, it is possible to calibrate electronically using a pulse
generator.
The standard radionuclide for calibration is Cesium-137. A certified calibration source should be used. To calibrate the
Inspector
+
for another radionuclide, you must use a calibrated source for that radionuclide or the appropriate conversion
factor referenced to Cs-137.
CAUTION:
Errors can occur when using low level sources or background to set
CAL factor. In the Calibration
mode, the smallest increment which can be adjusted is .010, which prevents fine adjustment of the CAL factor.
Calibrating Using a Source
1. Place the Inspector
+
or Inspector EXP
+
probe at a distance from the source that corresponds to a 50 mR/hr field with
the detector window facing the source.
2. Set the Inspector
+
mode switch to mR/hr.
3. Turn the Inspector
+
on.
4. Open the source and record 20 consecutive readings.
5. Close the source.
6. Calculate the average of the readings and record.
a) If the average is ± 10% of 50 mR/hr, go to Step 7.
b) If the average is not ± 10% of 50 mR/hr, go to Step 10.
7. Place the Inspector
+
or the Inspector EXP
+
probe at a distance from the source that corresponds to a 5 mR/hr field
with the detector window facing the source.
8. Repeat Steps 2 - 5.
9. Calculate the average of the readings and record.
a) If the average is ± 10% of 5 mR/hr, the calibration procedure is complete.
b) If the average is
not
± 10% of 5 mR/hr, go to Step 10.
10. Turn off the AUDIO in order to hear the count down timer sound.
11. Turn off the Inspector
+
. Hold down the “-” button on the end panel and turn on the Inspector
+
. The display shows
CAL, and the Inspector
+
counts down for 15 seconds, chirping each second. This delay gives you a chance to move
out of the field and then expose the source. At the end of the 15 seconds, the Inspector
+
beeps.
12. The Inspector
+
now collects data for 30 seconds, chirping every 2 seconds, with CAL and the hourglass icon flashing.
At the end of the 30 seconds, it beeps. The display shows CAL and SET is flashing.
13. Close the source.
14. Press the “+” and “-” buttons on the Inspector
+
to adjust the reading to what it should be.
15. When the reading is correct, press the Set button. The new calibration factor is displayed for several seconds, then
the Inspector
+
beeps and resumes normal operation.
16. Record the new calibration factor.
17. Place the Inspector
+
or the Inspector EXP
+
probe at a distance from the source that corresponds to a 5 mR/hr field
with the detector window facing the source.
18. Repeat Steps 2 - 5.
19. Calculate the average of the readings and record.|
a) If the average is ± 10% of 5 mR/hr, the calibration procedure is complete.
b) If the average is not ± 10% of 5 mR/hr, repeat steps 11 - 16 and go to step 20.
20. Calculate the average of the calibration factor for 50 mR/hr and the calibration factor for 5 mR/hr.
21. Turn the Inspector
+
off. Hold down the “+” button while turning the Inspector
+
on. The numeric display will show a
single number.
23. Press the “+” or “-” button until 7 is shown on the numeric display.
24. Push the Set button.
25. The calibration factor is displayed. Press the “+” or “-” buttons to adjust the calibration factor to the average
calibration factor calculated in Step 20.
26. Push the Set button to enter the new setting and resume normal operation.
The calibration factor is set to 100 (percent) at the factory. If you change the reading, for example, to 20% higher than the
factory reading, the new calibration factor would be 120. The current calibration factor is displayed during the system
Summary of Contents for Inspector EXP+
Page 1: ...User Manual...
