Abstract: This paper reviews standards of radioactive waste water concentration anddischarge used in some countries before 1977, and discusses the methods ofcalculation of MPC_w recommended by the ICRP publication 2. In order tocontrol the release of radioactive waste water to the environment and provide abasis for disposal of liquid effluent, derived water concentration (DWC) shouldbe taken into account. The calculation of DWC is based on the ALI of waterand limit of annual effective dose equivalent for the public. The recommendedconcentration is given in this paper.