Neutron Spectrum Measurement at the Workplace of Nuclear Power Plant with Bonner Sphere Spectrometer

Abstract

With BSS system, the neutron spectral fluences at the workplace of nuclear power plant at Wolsong were measured.The 9 points at the 4 th and 5 th floor of the reactor building were selected for the spectrum measurement, where the radiation workers access for the ordinary check of the operation.The spectra show the distribution from the thermal to several MeV, which are composed of the original fission spectrum, scattered fast neutrons and thermal neutrons.The spectral shapes for the places at the same floor are similar to each other.Although the number of data points is limited, we may determine the standard neutron spectrum for each floor and this would help improving the uncertainties of neutron doses.For the comparison, we measured the neutron ambient dose with neutron survey meter (EG&G Ortec, LB6411) and personal dose with TLD on PMMA phantom.