Radiation field estimation around CFVS shield structure

Containment filtered venting system (CFVS) has a concrete shield structure around the wet scrubber tank (ST). During design extension condition (DEC) with core melt scenario of a nuclear power plant (NPP), volatile and semi-volatile radionuclides vented from the containment are trapped in the ST Fission product radionuclides (e.g., Kr, Xe, I, Cs, Te, Sr etc.) are distributed in inlet pipe, outlet pipe, scrubber tank solution contribute to the radiation dose to the radiation worker. In this study, gamma source spectrum for inlet pipe line, outlet pipeline, scrubber tank solution are estimated taking into account the relative contribution of individual radioisotope. Axial radiation dose profile at the outer surface of the concrete shield structure has been estimated. (author)