The fission products release into reactor core and primary circuit lead to airborne
contamination as a result of helium that leaks from the system into the room. The
airborne activity was calculated by deriving and solving a differential equation
considering room ventilation and a twin room ventilation to check the effects of
ventilation system or migration of airborne activity to the other rooms. The HVAC
system was optimized by considering and comparing the activity calculated for
the three HVAC system models (i.e. recirculation with and without filter and no
recirculation of air or once through model) and by increasing the air change rate.
The activity calculated for each nuclide ~as used to calculate the annual dose
received by a worker spending 2000 working hours per year in the room. It was
found that the dose received for the three HVAC models differs. The recirculation
of air without filter was the most contributing in terms of dose followed by
recirculation of air with filter model then no recirculation model was the least
because there is no activity recirculated back into the room.
The filters used for recirculation of air with filter model are radioactively
contaminated, but the calculated filter activity was found to be low and can be
disposed as low level waste or can be continuously used with an efficiency test
regularly performed on the filters. / Thesis (MSc. ARST) North-West University, Mafikeng Campus, 2003
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:nwu/oai:dspace.nwu.ac.za:10394/11357 |
| Date | January 2003 |
| Creators | Makgae, Reuben Ephraim |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis |
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