DAILY INSPECTION
The gauge should be inspected daily before use to ensure proper
operation of all safety features as follows:
✓
Push the source rod down into the measurement position, and
then raise it back to the safe (shielded) position. The source rod
opening in the bottom of the gauge is equipped with a spring-
loaded tungsten sliding block that shuts when the source rod is
in the safe position. Turn the gauge over and verify that the
sliding block is completely shut. If any portion of the opening is
uncovered, the tungsten sliding block and fixed tungsten block
should be cleaned as described in Appendix C, page C–11
before using, transporting, or storing the gauge.
CAUTION
Do not store or transport the gauge unless the sliding
block is completely closed. Increased radiation levels
may violate transportation regulations and cause
excessive personnel radiation exposure.
✓
If a radiation survey instrument is available, verify that the
radioactive gamma source is in place by measuring the exposure
rate at the surface of the gauge. The exposure rate should be
approximately 10–20 mrem per hour. A reading of about
1 mrem or less indicates either that the survey instrument is not
working properly or that the cesium-137 source may be missing.
Refer to the
section of Appendix C for further
instructions.
3–2
Содержание 4640-B
Страница 6: ...NOTES vi...
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Страница 17: ...1 GENERAL INFORMATION Figure 1 1 Model 4640 B Parts and Accessories Model 4640 B 1 5...
Страница 22: ...NOTES 1 10...
Страница 26: ...NOTES 2 4...
Страница 84: ...NOTES Appendix A 12...
Страница 108: ...NOTES Appendix C 18...
Страница 130: ...NOTES Appendix F 8...