Maintaining the design integrity of nuclear installations throughout their operating life. INSAG-19. A report by the International Nuclear Safety Advisory Group

A nuclear power plant design is the product of the activities of many organizations, and changes to that design will occur continuously over the plant's lifetime. Reactor plants are designed to operate for a long period of time, typically 40 years, which may be extended for several decades. This period of time spans several working lifetimes of the staff of the plant, and its length represents a very specific challenge to safety and to the corporate asset management of the enterprise. It also implies that the vendor structure required to support the plant can be expected to change substantially during the plant's lifetime. this INSAG report discusses the problem of maintaining the integrity of design of a nuclear power plant over its entire lifetime in order to achieve a continuous high level of safety. A nuclear power plant design is the product of the activities of many organizations, and changes to that design will occur continuously over the plant's operating lifetime. Reactor plants are designed to operate for a long period of time, typically 40 years, which may be extended for several decades. This period of time spans several working lifetimes of the staff of the plant, and its length represents a very specific challenge to safety and to the corporate asset management of the enterprise. It also implies that the vendor structure required to support the plant can be expected to change substantially during the plant's lifetime. The purpose of this report is to identify the issues and some of the principles that should be addressed, discuss some of the solutions to the problem, and highlight the specific responsibilities of designers, operators and regulators. The issues and principles discussed here are also applicable to other nuclear installations (for example, research reactors and fuel cycle facilities). This INSAG report is directed at senior executives who are responsible for: the overall safety of nuclear installations; the operation, maintenance and modification of nuclear installations; the original design of nuclear installations, including the nuclear steam supply, the balance of plant and major components; regulatory supervision of licensee activities. It is designed to help them establish the necessary organization to ensure that the design integrity of the plant for which they are responsible is maintained throughout the plant life