ANSI/ANS-18.1-1999

Radioactive Source Term for Normal Operation of Light Water Reactors

This standard establishes typical long-term concentrations of principal radionuclides in fluid streams of light-water-cooled nuclear power plants for use in estimating the expected release of radioactivity from various effluent streams. These fluid streams are: the coolant of a boiling water reactor (BWR), the coolant of a pressurized water reactor (PWR), and PWR steam generator fluids. The concentrations in fluid streams of BWRs and PWRs are treated in a similar manner but have different numerical values because of the differences in design.The numerical values given in this standard are based on available data from operating plants which use zirconium-clad uranium dioxide fuel. The values are given for a set of reference conditions, and criteria are provided for adjusting to other conditions.