Activity of stack gases

2 Activity of Stuck Guscb. The activity in the stack gases due to air from the contaminated-air system will generally be negligible compared to that due to the.air from the reactor. Thus the design of the stack is based principally on.the radioactivity of the reactor-cooling air. 

The activity of the reactor-cooling air is due to radioactive particles and gases. For obvious reasons, the activity due to particles does not lend itself to calculation.. Therefore the activity of the, stack gases is considered to be.that due solely, tp the 110-min half-life.,A (argon) formed in,the re.aetor. i - 

The rate Of activation of the argon in the reactor-cboliiig air is given 

activation rates, for the va.rious regions.are, summarized in Table. 8.4.,A. The term air in graphite refers to the air spaces naturally occurring in graphite. 

REGION VOLUME (ft ), FLUXi J (neutrons/cm sec) ACTIVATION RATE ( atoms/sec) 

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