Shielding
Shielding is any material used to reduce the radiation reaching the
user from a radioactive source. While some types of radiation such
as alpha particles may be stopped by a single sheet of paper, other
particles such as gamma rays require much more shielding. Dense
materials, such as lead, shield gamma rays. The Model 4640-B has
shielding built into the system that reduces the exposure.
MONITORING RADIATION
In the United States, anyone working with or near radioactive
materials is subject to the limits on occupational exposure and must
complete a radiation safety training course to be designated an
authorized user. As an authorized user, an individual so designated
must work in a “controlled” environment to the extent that their
exposure to radiation must be monitored. Several means of
personnel monitoring or dosimetry exist; the most common methods
are film badges and thermoluminescent dosimeter (TLD) badges.
A. RADIATION THEORY
In Canada, nuclear gauge users are not normally classified as
Atomic Radiation Workers. In such cases, the general public dose
limit of 0.5 rem/year would apply. Users may not be required to
wear a dosimeter. To establish the personnel monitoring
requirements for your application, consult the conditions of your
radioisotope license and the AECB regulatory document R91
“Monitoring and Dose Recording for the Individual.”
Model 4640-B Appendix A–7
To Next Page
Loading...
