Troxler 4640-B, Operation And Instruction Manual

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RADIATION SAFETY
This section provides a brief discussion of general radiation safety.
The exposure profile for the Model 4640-B gauge is also included,
along with a discussion of the source encapsulation.
TYPES OF RADIATION
The radioactive source in the Model 4640-B produces two types of
radiation:
Beta particles
Photons (gamma rays)
The beta particles are stopped by the source capsule. Only the
gamma radiation contributes to any occupational radiation exposure.
Gamma radiation is electromagnetic radiation, as are x-rays, radio
waves, and visible light. Visible light and gamma rays have no
mass, a zero electrical charge, and travel at the speed of light.
Gamma rays are energetic and penetrating. Dense materials (such as
lead, cadmium, and so on) provide the best shielding against gamma
radiation.
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LIMITING EXPOSURE
WARNING
Do not tamper with or modify the Model 4640-B gauge.
Also, do not remove the sealed source from the gauge.
Tampering with or modifying the gauge or removal of
the sealed source can be dangerous. Such actions are
illegal unless authorized by your radioactive materials
license.
Government agencies set occupational exposure limits. The current
limit in the United States and many other countries is 5,000 mrem
per year. Under average conditions, a full-time employee working
with the 4640-B will receive less than 200 mrem per year.
Model 4640-B Appendix A–5