In water-cooled nuclear reactors, whenever the reactor is operating, the interaction between the neutron flux and the oxygen in the primary coolant produces 16N, a radioactive isotope of nitrogen. In case of a crack in one or more steam generator tubes, the amount of 16N leaking to the secondary coolant will be proportional to the leak size, the differential pressure between the primary/secondary loops and the concentration of 16N in the primary coolant, i.e., the reactor power level. Successful field-proven experience in providing cost-effective Steam Generator Leak Monitors (SGLM) and the software to support them is available to provide customers with added safe and reliable monitoring capabilities.
The SGLM 201K monitors steam generator leak rate in PWR nuclear power plants by measuring 16N volume activity.