Figure 4-1. Tritium facility single-pass ventilation system

DOE-HDBK-1129-99

Air Intake

Pressure zone control used to move air from

lower contamination areas to higher

High-velocity air hood

contamination areas, and then out the stack

Typical face velocity of

150 lineal ft/min

FIGURE 4-1. Tritium facility single-pass ventilation system

4.1.1.a Containment and Confinement Systems

There are many different technical descriptions of the terms containment and confinement. The

simple dictionary definitions are: containment being contained, which in turn is to hold or

enclose; and confinement being confined, which in turn is to restrict, to keep within limits. It is

beneficial to define how these words are used in the tritium field. In some facilities and

applications, the terms are used interchangeably. The Tritium Focus Group definitions are defined

in Appendix B, Definitions. This Handbook, as noted in the Definitions, makes a distinction

between these terms as follows:

Containment system A collection of passive barriers that can satisfy a specified leak criterion

without operation of any ancillary equipment. An example of a containment system is a series of

piping and vessels enclosing tritium gas operations.

Confinement system A collection of barriers that can satisfy a specified leak criterion contingent

upon operation of its ancillary (active) system. An example of a confinement system is a glovebox

and its associated cleanup system.

Note that in the context of these definitions, a glovebox with an associated glovebox cleanup

system is a confinement system. A glovebox structure itself is a containment system if, and only if,

the specified leak criterion can be met by the structure itself.