Secondary Confinement System

DOE-HDBK-1132-99

Space and equipment should be provided as needed to support

accountability, process monitoring, and material control

requirements.

Exhaust prefilters and HEPA filters should be installed to facilitate

filter replacement and repair.

Standby filters should be incorporated for backup protection

during filter changes so that filters can be changed without

shutting down the exhaust fans. Standby filters should be

installed outside the cell and sealed in an acceptable enclosure

for direct maintenance.

Exhaust systems should have alarms that will annunciate if the

concentration of radioactive material in the exhaust exceeds the

limits specified in the facility technical safety requirement.

Secondary Confinement System . The secondary confinement system usually

consists of the facility operating compartments and associated ventilation

systems. The secondary confinement houses the hot cells, gloveboxes, fume

hoods, etc. The following design features should be incorporated into

secondary confinement systems for laboratory facilities:

design features to minimize the potential of the spread of contamination

from within the laboratory facility operating areas to areas that are not

normally contaminated;

the use of a ventilation system separate from the primary confinement

ventilation system with appropriate air-cleaning capability (e.g., HEPA

filtration, radioiodine absorbers, scrubbers); and

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