Contamination Control

DOE-STD-1128-98

Guide of Good Practices for Occupational Radiological Protection in Plutonium Facilities

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CONTAMINATION CONTROL

The primary control for contamination in a plutonium plant is the facility design. Contamination is

confined primarily by enclosing the process areas and using controlled ventilation systems.

Appendix C of this guide addresses the different levels of confinement in a plutonium facility. The

design objective for the confinement system is to essentially prevent or minimize exposure of plant

personnel and the public to airborne contamination. To ensure that this objective is met, additional

attention should be given to air contamination control, surface contamination control, and personnel

contamination control. Radiological controls for the workplace should ensure that radionuclides are

contained and handled properly and that intakes, if they occur at all, are negligible to the extent

achievable with state-of-the-art technology. However, much of the current effort involves

decommissioning of no-longer-needed production facilities. The lack of engineered controls or the

systematic removal of existing controls during the decommissioning process introduces a

completely different set of circumstances that requires special attention for adequate contamination

control and worker and public protection.

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AIR CONTAMINATION CONTROL

To achieve the design objective of preventing (or at least minimizing) internal exposure of plant

personnel, airborne contamination must be confined to process enclosures which have adequate air

cleaning systems. Because both equipment and personnel errors can compromise designed

protection and because older facilities may already have unconfined plutonium, air monitoring and

other contamination control measures are needed. Experience has shown that the most common

route for inadvertent plutonium deposition in man is by inhalation even though intakes may also

occur by accidental ingestion or by wound contamination. In facilities being decommissioned, the

use of temporary containment structures, interim ventilation systems, and administrative controls

such as protective clothing and respirators may be required to replace engineered systems.

10 CFR 835.1002 requires that for the control of airborne radioactive material, the design objective

shall be, under normal conditions, to avoid releases to the workplace atmosphere and in any

situation, to control the inhalation of such material by workers to levels that are ALARA;

confinement and ventilation shall normally be used. See Appendix C for Facility Design guidance.

Note: The use of ventilation systems may require the approval of Facility Criticality Safety

personnel because these systems may concentrate fissionable material.

4.1.1 Internal Versus External Dose Philosophy

The overall goal of radiological protection is to minimize the total dose to the individual.

However, because of the difficulties and cost of an adequate internal dosimetry program for

plutonium exposure, it is best to avoid all internal exposures during routine operations and

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