A formal definition of a regulatory framework may be considered as a system of regulations and the means to enforce them, usually established by a government, to regulate an activity. A framework may also be consid­ered as a skeleton or a work platform that is used as the basis for construct­ing the regulatory system; the framework considers a set of assumptions, concepts, criteria and practices that constitute the means of implementing the regulatory functions.

The legal system, regulations and the regulatory structure and approach constitute the regulatory framework. This may vary significantly from one State to another in its complexity, arrangements, criteria, culture and prac­tices. The approaches used in States with large nuclear power programmes may differ from those in States with small nuclear power programmes. Also, the approaches in States with a nuclear power plant vendor may differ from those in States that import nuclear power plants.

The regulatory framework needs to be based on the chosen approach and there should also be the scope for development or further adjustment as the knowledge, experience and needs of the regulatory body change. The regulatory approach is used to provide the basis for the nuclear safety regu­lations; to provide the regulatory actions and safety decisions; and to estab­lish the safety rationale that is clearly understood by the regulator, the licensee and other stakeholders.

Regardless of the approach chosen, the framework needs to be devel­oped so that there are enough staff to cover all core competences necessary to understand all the relevant safety issues of the nuclear power programme. The regulatory approach also has implications for the need for external expert support for the regulatory body.

In order to select and plan the regulatory approach, the regulatory body considers the various regulatory approaches that are applied for nuclear power programmes elsewhere, taking into account the nuclear power plant size, the State’s legal and industrial practices and the guidance provided in the IAEA Safety Standards.

The regulatory approach has an impact on the licensee and also indirectly on the safety of the nuclear facilities. Regardless of the approach selected, the regulator needs to provide clear requirements to the licensees, including its safety expectations; the regulator needs to be able to identify safety significant issues, the areas of expertise needed by the regulator and licen­sees respectively, the resources used by the regulators and the licensees, and the level of flexibility given to the licensee to fulfil requirements; the regula­tor also needs to achieve public credibility for the way in which safety is regulated.

The development of the regulatory framework involves maintaining a balance between prescriptive approaches and performance-oriented approaches. This balance might also depend upon the State’s legal system and regulatory approach. The approach chosen will have a major influence on the resources needed by the regulatory body, therefore the various applicable approaches need to be considered in good time, and before start­ing the recruitment of staff due to the impact of the approach chosen on the number and qualifications of the regulatory staff required. Before the State decides which reactor technology is going to be deployed, the regula­tory body has to be aware of these two main alternative regulatory approaches: a prescriptive approach with a large number of regulations, or a performance-, function — and outcome-oriented approach. Each regulatory approach has advantages and disadvantages associated with it, and there are also approaches that combine features of these two main alternatives. When a decision to construct a nuclear power plant is made, and the par­ticular reactor technology is chosen, the regulatory body needs to select and adopt a regulatory approach that best suits the State’s needs. The regulatory body should have its chosen approach approved by the government since there will be resource implications.

A prescriptive regulatory approach places a great deal of importance on the adequacy of the regulations for safety and requires detailed develop­ment. The regulations establish clear requirements and expectations for the regulatory body as well as for the operating organization, and thus can be used to promote systematic interaction between the regulatory body and other parties. The regulations could set detailed technical requirements, or could identify issues that the operating organization and its suppliers should address and present for assessment by the regulatory body. Specific techni­cal requirements can then be taken from relevant international industrial standards (including nuclear specific standards) or industrial standards of other States, as agreed by the regulatory body in an early stage of the licens­ing process for nuclear power plants. Issuing detailed regulations places a high demand on the regulatory body’s resources for their development and updating, which adds to the administrative burden.

A performance-based regulatory approach allows the operating organi­zation more flexibility in determining how to meet the established safety goals and may require fewer, less detailed regulations. However, this approach requires the establishment of specific safety goals and targets. Verifying that appropriate measures to ensure safety have been identified by the operating organization may be difficult unless the regulatory body’s staff, the staff of its external support organization and the staff of the oper­ating organization all have a high level of professional competence and are able to interact to determine whether established safety objectives for each topic are met.

Besides the general alternatives just described, the approaches in differ­ent States vary with respect to the scope and depth of safety assessment and inspection. The scope of issues that are under regulatory control may include all structures, systems and components classified as safety-relevant or may be limited to the most safety-relevant parts only. The targets of the comprehensive and systematic regulatory control and inspections are specified in a deterministic manner, on the basis of a safety classification, or they can be chosen on the basis of a probabilistic assessment of risks. As to the depth of the review, in some States the regulatory body puts the main emphasis on the assessment and auditing of the management system
and the operations of the operating organizations and their suppliers. In other States the regulatory body prefers to make comprehensive inde­pendent analyses and inspections of its own. INSAG has developed the nuclear safety infrastructure necessary for a national nuclear power programme supported by the IAEA Fundamental Safety Principles (INSAG, 2008).