Radiation monitor maintenance issues challenging our industry—Is this an unintended consequence of the Maintenance Rule?

Eric Darios

Billy Cox

Arguably, nowhere does a more robust safety culture exist than in nuclear, an industry that is a model of a learning organization, dedicated to continuous improvement through transparency in identifying and correcting errors and failures. Over the course of maintenance and outage planning, the cornerstones of reactor safety are considered in every decision regarding maintenance and outage activities. Radiation monitoring systems in nuclear power plants are vital to plant safety and regulatory compliance. In addition to the 10 CFR 20 applications, the industry relies on radiation monitors for measuring effluents (RG 1.21, RG 4.15, and Part 50 App A GDC 64), reactor pressure boundary leakage (RG 1.45), and PWR primary to secondary leakage, and to assist in emergency classification (RG 1.97). The Nuclear Regulatory Commission’s well-intended Maintenance Rule places maintenance priorities on systems, structures, and components (SSCs) used to mitigate accidents and SSCs used in emergency operating procedures (EOPs). The Maintenance Rule also includes SSCs whose failure could prevent a safety-related SSC from fulfilling its safety-related function and SSCs whose failure could cause a reactor scram or actuation of a safety-related system. Unfortunately, the narrow scope of the Maintenance Rule leaves a significant portion of radiation monitoring systems outside the scope of the rule, which often delays repairs.