Radiological Safety Training for Uranium Facilities
Module 104 Internal Dose Control
radioactive decay products is about 30 minutes, compared with the
millions of years it takes for uranium to decay. The simple way to
determine if contamination is due to radon is to wait and see if it goes
away. The sample is recounted after the radon has an opportunity to
decay to lower levels. The count rates are compared, and if the count
rates are significantly different, radon is the most likely reason for the
higher initial count rate.
Special Radiological Surveys and Techniques for Release of Materials
with the Potential for Uranium Contamination.
The alpha contamination detection problems mentioned in monitoring
personnel for contamination also apply to monitoring material. An added
problem is that uranium contamination may be located in areas not
accessible to survey.
DOE requires that materials used in Contamination Areas, High
Contamination Areas, and Airborne Radioactivity Areas that are being
released for unrestricted use have accessible surfaces surveyed. Materials
with inaccessible surfaces having a potential for internal contamination
shall not be released without evaluating the material on a case-by-case
basis to ensure internal contamination does not exist.
DOE values for release of uranium- contaminated materials are higher
than DOE values for release of materials contaminated with some other
radioactive nuclides found in the DOE system, such as plutonium. The
difference in these values is due to the relative health risk from exposure
to uranium contamination compared with these other nuclides.