Abstract: Nuclear power reactor units have the ability to provide large-scale, stable industrial steam. Laboratory measurements show that, under the condition of no leakage in the heat transfer tube of the steam generator, the concentration of radionuclides in the condensed water of the second-loop steam is not different from that in the environmental water sample except for tritium. Based on the drinking water standard, this article proposes to control the target value of radionuclide management for industrial application of second-loop steam at 3.0 Bq/kg; A high-sensitivity radiation monitor was set up on the steam generator drainage pipeline and technical renovation on the main steam pipeline N-16 radiation monitoring channel was carried out, with the aim to provide timely, effective, and reliable monitoring of steam generator heat transfer tube leakage. It is interlocked with the control valve of the external steam supply pipeline at the factory boundary to prevent radionuclides from leakaging outside the factory area through the steam supply pipeline during operation and accident conditions.

Key words: PWR, industrial steam, leakage monitoring, tritium