Feature Article

Risk-informed, performance-based safety: Past, present, and future

Since the 1980s, the nuclear power industry in the United States has worked to enhance the regulatory framework for nuclear facilities by making it more risk-informed and performance-based (RIPB). This has had some success in improving safety and reducing regulatory burden by focusing resources on the most risk--significant areas and allowing greater flexibility in choosing ways to achieve desired safety outcomes. However, there are further opportunities for the use of RIPB approaches in addressing current regulations and applying implementation tools, and in developing new RIPB regulations and advanced tools to further sharpen the focus on risk and performance outcomes.

Standards Community of Practice for RIPB methods

The Risk-informed, Performance-based Principles and Policy Committee (RP3C), a special committee of the ANS Standards Board, has launched a Community of Practice (CoP) to support risk-informed, performance-based (RIBP) methods in ANS standards. The CoP consists of interested professionals who can contribute to standards development priorities identified in the Standards Committee Strategic Plan and in ANS Position Statement #46, “Risk-Informed and Performance-Based Regulations for Nuclear Power Plants.”

ANS publishes revised standard on PWR reload startup physics tests

The ANS Standards Committee has just published ANSI/ANS-19.6.1-2019, “Reload Startup Physics Tests for Pressurized Water Reactors” (revision of ANS-19.6.1-2011). The standard, approved December 19, 2019, provides guidance for verifying the nuclear characteristics of a commercial pressurized water reactor core following a refueling or other alteration of the reactor core for which nuclear design calculations are required. The standard provides the minimum acceptable startup physics test program, while recognizing that additional tests may be required by special design features of a particular core.