Special Radiological Surveys - doe-hdbk-1113-98_reaffirm_2005

DOE-HDBK-1113-98

Module 104 Internal Dose Control

Lesson Plan

Instructor's Notes

Radon is a radioactive gas that occurs

naturally in the environment. It decays

by alpha emission in the first of a series

of very short half-life radionuclides

that decay by alpha or beta-gamma

emission.

There is a simple, inexpensive

alternative to determine if the

contamination is due to radon. The

effective half-life for radon 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 Highlight the radioactive

contamination limits used

count rate.

for

release of materials and

Special Radiological Surveys and

equipment at your facility.

Techniques for Release of Materials with

the Potential for Uranium Contamination