Monitoring Requirements and Selection of Employees

DOE-STD-1128-98

5.3.2 Monitoring Requirements and Selection of Employees

Workers who are considered likely to have intakes resulting in excess of 100-mrem

CEDE are required to participate in a bioassay program. However, because of the

extensive radiological control practices for plutonium facilities, including a high

degree of engineered barrier containment, no typical plutonium worker is likely to

have intakes of 100-mrem CEDE or more. However, this should not be used as an

excuse to exclude workers from routine bioassay. Although no one should be

considered likely to have intakes resulting in 100-mrem CEDE, some workers are at

significantly higher risk for incurring an intake than others and should be on routine

bioassay.

The workers at highest risk of incurring an intake are the ones in closest contact with

the material. Typically, these are the operators, maintenance, and health physics

personnel handling plutonium or plutonium-contaminated objects in the course of

routine glove-box, maintenance, or decommissioning operations. In the event of

containment system failure, or failure respiratory protection devices, it is these

workers who will most likely incur exposure and subsequent intake. These workers

should be on a routine bioassay program designed to meet the requirements of 10

CFR 835 (DOE, 1998a) as a kind of safety net to identify intakes which might have

gone undetected by workplace monitoring.

Other workers (e.g., supervisors, inspectors, observers, guards, and tour groups) who

work in or visit a plutonium facility but are not directly working with the material or

contaminated objects are at a substantially lower risk for incurring an intake.

Although these people may not need to be on a routine bioassay program, they should

be subject to participation in a special bioassay program if workplace indications

suggest loss of control or containment.

5.3.3

Selection of Bioassay Monitoring Techniques

Bioassay monitoring techniques fall into two broad categories, direct measurement of

radioactive materials in the body (in vivo counting) and analysis of material removed

from the body for laboratory in vitro analysis. In vivo counting includes

measurements of the chest, lung, skeleton, liver, and wounds. In vitro measurements

include urinalysis, fecal analysis, and occasionally analysis of tissue, sputum, or

blood samples. Methods for in vitro analysis include liquid scintillation counting,

fluorescence measurements, gamma spectrometry, chemical separation followed by

electrode position, and counting with radiation detectors. Selby et al. (1994) provide

a brief overview of bioassay techniques and capabilities. Further discussion of the

techniques is provided below.

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