Indicator and Action Levels

DOE-STD-1128-98

Guide of Good Practices for Occupational Radiological Protection in Plutonium Facilities

clearance rate. These unknowns can be dealt with by assuming a standard isotopic

composition at the time of intake and then solving the equation for a biological clearance

rate using an iterative process until the calculated result matches the observed result at a

given time t. A computer or calculator algorithm can eliminate the need for lengthy hand

calculations.

Once an optimum combination of isotopic compositions and biological clearance rate is

found, internal dosimetry codes or hand calculations can be used to estimate organ and

effective doses. As a check on the results, standard computer codes can be used in an in a

bioassay projection mode to project the 241Am content based on the estimated intake and

biological clearance rate.

5.9 INDICATOR AND ACTION LEVELS

Indicator and action levels are essential to operation of a routine internal dosimetry program.

Because a wide range of levels can be defined by various facilities and organizations, this document

does not attempt to prescribe particular level titles. As used in an in this document, indicator and

action levels are simply workplace or bioassay measurements, or associated calculated doses, at

which specific actions occur.

Indicator levels based on workplace indicators for reacting to a potential intake are suggested in an

in Table 5.7. The intent of these indicator levels is to provide guidance for field response to any

potential intake of radioactive material with a potential for a dose commitment that is >100-mrem

CEDE. It is suggested that when these levels are reached, appropriate management members of the

health physics and operations organizations be informed. See Section 5.4.3 for guidance on special

bioassay. Table 5.8 suggests notification levels to the occupational medicine physician for possible

early medical intervention in an in an internal contamination event. These tables, derived from

Carbaugh et al. (1994), are based on general considerations and significant experience with past

intakes of radioactive material and, because they are based on field measurements, do not correspond

with any exact dose commitment to the worker.

The decision to administer treatment and the treatment protocol are solely the responsibilities of the

physician in an in charge. The basic principle is that the proposed intervention should do more good

than harm (Gerber and Thomas, 1992).

Guidelines for the medical intervention of a radionuclide intake can be found in an in several

publications. NCRP Report No. 65 (NCRP, 1980) and the joint publication of the Commission on

European Communities (CEC) and the DOE Guidebook for the Treatment of Accidental Internal

Radionuclide Contamination of Workers (Gerber and Thomas, 1992) both contain detailed guidance

in an in intervention and medical procedures useful in an in mitigating radiation overexposures. The

ICRP recommends in an in Publication 60 (1991b) a limit of 2-rem/y (20-mSv/y) on effective dose.

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