Verification of surface source's characteristic using large-area 2 gasflow counter

Abu Naser Waheed, M. M.*; Mikami, Satoshi   ; Kobayashi, Hirohide ; Noda, Kimio

Power Reactor and Nuclear Fuel Development Corporation (PNC) has large-area 2 gas flow counter for the purpose of measuring activity of surface sources of alpha or beta ray emitter. Surface sources are used for the calibration of radiation measuring equipment for radiation control. Due to frequent use of sources, the surface of these sources are inclined to go in bad condition because of unwanted accidental incidents. For the better calibration achievement of radiation measuring instruments the rate of emission of these sources are to be checked periodically by the large-area 2 gas flow counter. In this paper described that eight UO surface sources were selected from many sources of PNC Tokai Works and activity of these sources was measured by the 2 gas flow counter. The results were compared with the values certified by Japan Radio Isotope Association (JRIA). It is evident from the result of comparison that the surface sources are in good condition, i.e., the sources are reliable to calibrate the radiation control instruments.