ATOMIC REACTOR STATE MONITORING DEVICE AND MONITORING METHOD THEREOF

摘要

An atomic reactor state monitoring device (1) comprises: a gamma ray measurement device (17, 23) which is on the storage container (10) side of a biological shield wall (11) which surrounds a pressure container (2), detects an atmospheric gamma ray quantity from a radioactive substance outside the pressure container (2), and measures the gamma ray quantity; a gamma ray measurement device (15, 21) which detects a gamma ray quantity on the pressure container (2) side of the biological shield wall (11) and measures the gamma ray quantity; a gamma ray measurement device (16, 21) which detects the gamma ray quantity of a fuel (3) which is housed in the pressure container (2) and measures the gamma ray quantity; and a water quantity evaluation device (24) which derives, as a post-correction fuel gamma ray quantity, the difference between the gamma ray quantity measured by the gamma ray measurement device (16, 21) and the gamma ray quantity measured by the gamma ray measurement device (17, 23), and, using the post-correction fuel gamma ray quantity, acquires, as a water level evaluation value, the water level of coolant water (4).