IEEE P338/D4

IEEE P338/D4 is a draft nuclear engineering standard focused on criteria for the periodic surveillance testing of nuclear power generating station safety systems. It addresses how ongoing testing should help confirm that safety systems remain capable of performing as intended over time. For plant operators, engineers, and compliance teams, this document is relevant because surveillance testing is central to maintaining confidence in critical protection functions and supporting consistent operational oversight.

Overview of IEEE P338/D4

This draft standard sets out technical criteria for periodic surveillance testing within nuclear power generating station safety systems. IEEE P338/D4 is tied to the controlled verification of system readiness, helping define how tests are planned, applied, and evaluated in a safety-critical environment. As a revision of ANSI/IEEE Std 338-1987, it reflects a structured approach to maintaining test discipline for equipment that supports plant safety and operating assurance. It is intended for use where repeatable, well-defined surveillance practices are needed.

Typical use cases

IEEE P338/D4 is typically used when developing or reviewing surveillance programs for nuclear plant safety systems, including protection logic, associated control equipment, and related test procedures. It may guide maintenance engineering teams, test coordinators, and licensing support staff who need to confirm that safety functions remain dependable between scheduled inspections. The standard is also relevant during procedure updates, outage planning, and technical review of periodic tests for systems that must remain available and properly aligned for safe station operation.

Why it matters

Periodic surveillance testing is a practical safeguard against hidden degradation, configuration drift, and overlooked failures in safety-related equipment. IEEE P338/D4 matters because it helps support consistent test expectations, stronger documentation, and more defensible compliance in a regulated nuclear setting. Using a defined standard can reduce ambiguity in test scope and acceptance criteria, which may improve reliability, support risk reduction, and strengthen confidence in the performance of safety systems. For organizations working with IEEE P338/D4, it can also aid procurement and procedure control.

• Periodic surveillance testing criteria
• Nuclear power station safety systems
• Draft revision of ANSI/IEEE Std 338-1987
• Test planning and acceptance discipline