A new global standard will contribute to achieving the nuclear power industry’s continuing emphasis on the integrity of its safety-related equipment and practices, as global demand for nuclear energy rebounds.

In March, the IEEE and the IEC (International Electrotechnical Commission) announced their approval of IEC/IEEE 60780- 323™-2016, which provides consistent principles, methods and procedures for cost-effectively qualifying safety-related electrical equipment deployed in nuclear power plants around the world.

Adoption of the standard consolidates the requirements to which vendors must qualify their equipment, and minimizes the documentation required for compliance with standards. The net result contributes to improved safety for nuclear power. It also eliminates the burden on manufacturers to prove their compliance to the sometimes disparate requirements of individual customers around the world. The new standard and other efforts also make it simpler and easier for customers to ensure vendor compliance to equipment qualification requirements.

Why is this development important? “Important to Safety” electrical equipment is designed and relied upon to shut down a reactor in an orderly manner in case of an accident or design basis event, in what is potentially an extremely harsh environment. IEC/IEEE 60780- 323 establishes the process by which equipment manufactures demonstrate that their equipment will perform in those harsh environmental conditions, as well as afterwards for post-accident monitoring.

Conditions inside a nuclear plant during a design basis accident can exceed peak temperatures of 350 degrees Fahrenheit, 50 pounds of pressure, 200 megarads of radiation and contact with a caustic spray that’s injected into a plant during these events.

Moving to one standard
The unified global standard, IEC/IEEE 60780-323, is based on the historical fact that the global nuclear industry had two separate standards to choose from. Until now, IEC 60780 existed for the European Union and countries that turned to the EU for guidance in this area. The IEEE 323 family of standards served the United States and stakeholders who adopted its provisions.

The unification of these existing standards eliminates the duplication of equipment testing by manufactures that serve both markets. This is the first step in bringing the entire world into standards-based compliance for the qualification of “Important to Safety” equipment. When the end-user utility buys such equipment, it can rest assured that the product meets a single global standard.

Changing market
This approach is increasingly important as more manufacturers enter the nuclear market to provide components needed in the next generation of nuclear power plant designs. These new reactor designs will be built in many areas of the world that do not have an established history of operating nuclear power plants, nor strong regulatory oversight. Within these emerging markets for nuclear power plants, a single joint standard will provide a stable base for the future of the nuclear power industry.

In other words, countries and companies that did not participate in the first generation of nuclear power plants are now taking leadership positions in the development of the next generation of nuclear power plants. The challenge to the nuclear industry is how to effectively transfer knowledge and lessons learned from past decades to a new generation of nuclear engineers.

Adherence by manufacturers and nuclear power plant owners to a global standard for ‘Important to Safety’ electrical equipment is a strong step towards a safer, more cost-effective nuclear power industry. Plant designers can better focus their work by designing to the new standard as well.

History of standard, unified effort
IEEE 323 and its daughter standards have been in development since the early 1970s. IEC 60780 was first published in 1981. Most existing nuclear power plants, worldwide, are committed to meet one of these qualification standards. These existing nuclear power plants must meet the standards in which they committed to when they were licensed. New plants would need to meet the new unified standard if and when, as expected, it is adopted by the EU and the U.S.’s Nuclear Regulatory Commission (NRC).

The two standards development organizations decided in 2010 to collaborate on unifying their respective standards and, therefore, advance the safety of nuclear power through the use of a single global standard.

Conformity assessment
A separate but related effort is underway to simplify and reduce the cost to vendors and customers of the process for assessing equipment’s conformity to standards, whether that’s their legacy obligation to meet a historical version of the qualification standard or a new plant’s need to meet the new, unified standard.

The IEEE Nuclear Power Conformity Assessment Program is being developed collaboratively by the IEEE Nuclear Power Engineering Committee (NPEC) and the IEEE Conformity Assessment Program (ICAP).

A conformity assessment program would ascertain that components are genuine (counterfeit parts have been detected in the supply chain) and, as components have become more complex, new failure modes must be evaluated.

In addition, a single, global format for reporting testing information would give oversight authorities an apples-to-apples means of assessing compliance with standards. If the NRC looks at a test report at one location for one power plant and determines it is acceptable, then there’s no need to duplicate that effort for another plant because the test report will reflect the same information.

Meeting the requirements of the ICAP should provide vendors with a commercial advantage in the global market. Nuclear power plant owners, the end users, can rely on equipment that meets these requirements, without having to ensure compliance on a case-by-case basis.

Next steps
The goal of all these efforts is to insure that “Important to Safety” equipment meets the highest global standards, wherever it is produced or implemented, and that oversight is simplified and streamlined through a robust and consistent assessment and reporting process. This represents a powerful, relatively inexpensive solution to a major safety concern raised by the nuclear power industry itself.

Work on gaining adoption of the IEC/IEEE 60780-323 standard by relevant authorities continues and development of the conformity assessment program and reporting template is making progress.

The market-driven need for these measures has been recognized and met with thoughtful action to ensure the safety of nuclear power in a changing world.
 

About the Author

John White, chair, IEEE Working Group 2.1 on Equipment Qualification, Senior Consultant, True North Consulting.