Corrosion product behaviour in the Sizewell B PWR

Primary water chemistry control during operation and shutdown is important for the development of radiation fields during station life. At Sizewell B elemental corrosion product measurements have been made since the initial passivation of the primary circuit during the hot functional tests. This paper describes the change in corrosion product concentrations since HFT and discusses their relevance to the low radiation fields measured at the end of Cycles 1 and 2. Details are also given of the behaviour during the Cycle 2 shutdown and the corrosion product behaviour is discussed in relation to the origins of the radionuclides released during the acid-reducing and acid-oxidising phases of the shutdown. (author)