Personnel doses at NPP with WWER and trends in improving primary coolant circuit water chemistry

Analysis of operational data of radiation and chemical monitoring of power units with WWER in operation in the USSR is performed. Generalized results of radiation monitoring of NPPs with WWER type reactors for the recent years are presented. It is shown that the mean value of personnel radiation dose in 1988-1989 made up about 0.5 cSv/year. It is ascertained that the most intensive growth of the bulk of repair works, radioactive contamination of the equipment and doses resulted from the above factors is observed during the first 5-10 operation years after which their stabilization takes place. Problems of water-chemical regimes (WCR) of domestic and foreign NPPs are considered. Prospects of introducing especially with the beginning of operation of pressurized water reactors the WCR with a constant increased pH level (at the operating temperature) with regard to particular composition of corrosion products are shown