Sources of Tritium - hdbk1132990103

DOE-HDBK-1132-99

By the early 1970s, entirely new facility designs began to emerge. Having

adapted to the lessons learned from the earlier operational changes, these

newer facility designs also placed the bulk of the equipment that handled

substantial quantities of tritium into gloveboxes. Rather than having

individualized glovebox cleanup systems, the cleanup systems used in the

newer facility designs heavily emphasized the use of a centralized cleanup

system for glovebox operations. Evacuable covers were sometimes placed

over glovebox glove ports to minimize the potential for permeation from the

gloveboxes to the working rooms. Additional cleanup systems were installed to

handle the emissions from the glove port covers and other vacuum systems

that were not compatible with the centralized glovebox cleanup system. Real-

time monitoring capabilities were added to the gloveboxes and cleanup

systems to track their respective reliabilities. Rapid response, real-time

monitoring capabilities were added to the room air monitoring capabilities to

protect the worker further. Rapid response, real-time monitoring capabilities

were also added to the stack exhaust monitoring capabilities to more reliably

monitor releases to the environment. And, in some cases, specialized cleanup

systems were added at the room air ventilation level to allow for the cleanup of

large releases into a working room, before the tritium released into the

ventilation system was finally released to the stack.

With more than 25 years of operational experience with various types of newer

facility designs, it is clear that the bulk of the emissions from all tritium facilities

over the last 25 years have come from the background emissions of the

facilities themselves.

To better understand how these emissions come about, an appreciation for the

behavior of tritium in the facilities is necessary. Once understood, prospective

designers and engineers will begin to understand what they can and cannot

control through design innovations and techniques.

Sources of Tritium . Tritium is the lightest of the naturally occurring radioactive

2.10.2

nuclides. Tritium is produced in the upper atmosphere as a result of cascade

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