Primary Confinement System

DOE-HDBK-1132-99

levels of confinement are necessary or justified. Design decisions for a specific

facility should address that facility' hazards and other factors.

Primary confinement is usually provided by piping, tanks, gloveboxes,

encapsulating material, and the like, and any off-gas system that

controls effluent from within the primary confinement. It confines

hazardous material to the vicinity of its processing.

Secondary confinement is usually provided by walls, floors, roofs, and

associated ventilation exhaust systems of the cell or enclosure

surrounding the process material or equipment. Except for glovebox

operations, the area inside this barrier provides protection for operating

personnel.

Tertiary confinement is provided by the walls, floor, roof, and associated

ventilation exhaust system of the facility. Tertiary confinement provides a

final barrier against release of hazardous material to the environment.

1.1.3

Primary Confinement System. Primary confinement consists of barriers,

enclosures, gloveboxes, piping, vessels, tanks, and the like that contain

radioactive or other hazardous material. Its primary function is to prevent

release of radioactive or hazardous material to areas other than those in which

processing operations are normally conducted.

Primary confinement of processes that involve readily dispersible forms of

material (e.g., solutions, powder or small fragments, gases) is provided by

gloveboxes or other confining enclosures. Hoods are used when hazards are

acceptably low, as indicated by the quantity of the material involved, the specific

operation to be performed, and the hazardous nature and chemical form of

material involved. The confinement philosophy described below should be

applied to any component that serves a primary confinement function, such as

conveyor systems, material transfer stations, and ventilation/off-gas systems.

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