Operability Guidance

10 CFR Section 50.36 requires that each applicant for a license authorizing operation of a production or utilization facility include in its application proposed technical specifications (TS). This regulation also requires the TS to include limiting conditions for operation (LCO) and defines LCO as the lowest functional capability or performance levels of equipment required for safe operation of the facility. The regulation requires that when an LCO of a nuclear reactor is not met, the licensee shall shut down the reactor, or follow any remedial actions permitted by the TS until the condition can be met.

The operability determination process is used to assess the ability of TS required structures, systems or components and their support systems for compliance with TS when a condition impacts a necessary function or related support function.


NRC Inspector Manual Chapter (IMC) 0326, "Operability Determinations," (ML19273A878) dated October 1, 2019, was issued to assist NRC inspectors in their review of licensees' operability determinations. The information contained in IMC 0326 provides inspectors guidance regarding the process for evaluating operability determinations performed by licensees and ensures inspectors evaluate licensees' operability determinations consistently throughout the agency utilizing sound engineering practices. It also provides references to guidance/documents available to aid inspectors when assessing operability determinations.