Estimation of neutron and gamma dose equivalent rates on plutonium oxide container

摘要

The neutron and gamma dose rate measurements were essential around the storage container of PuO_2 for operational radiation protection purpose. In the present study, various types of active dose rate meters and passive dosimeters were used for the measurement of neutron and gamma dose rates in addition to the theoretical calculations. The neutron and gamma dose rate on the surface of PuO_2 container varied from 0.42 mSv/h to 0.71 mSv/h and from 1.83 mSv/h to 2.15 mSv/h respectively which decreased with increasing distance from the surface of the container. The neutron dose rates calculated theoretically did not match with that of experimental values at shorter distances, however, at larger distance such as 20 and 50 cm the agreement between theoretical and experimental values were reasonably good. The observations also suggested that the neutrons emitted from PuO_2 were mostly above the thermal neutron energy. The theoretical value of gamma dose rate on the surface and at distances from the bird cage matches very well with the measured values. The gamma dose rates are quite higher than the neutron dose rates for PuO_2 container.