CHAPTER 3: INTRODUCTION TO ACCIDENT MANAGEMENT

Acceptance criteria

Acceptance criteria are used in the design phase as well as during deterministic safety analysis to assist in judging the acceptability of the results of the analysis as a demonstration of the safety of the nuclear power plant. The acceptance criteria can be expressed in general, qualitative terms or as quantitative limits. Three categories of criteria are recognized:

• Safety criteria: Criteria that relate either directly to the radiological consequences of operational states or accident conditions, or to the integrity of barriers against releases of radioactive material, with due consideration given to maintaining the safety functions.
• Design criteria: Design limits for individual structures, systems and components, which are part of the design basis as important preconditions for meeting safety criteria.
• Operational criteria: Rules to be followed by the operator during normal operation and anticipated operational occurrences, which provide preconditions for meeting the design criteria and ultimately the safety criteria

Acceptance criteria may be used in order to:

• Set numerical limits on the values of predicted parameters.
• Set conditions for plant states during and after an accident.
• Set performance requirements on systems.
• Set requirements on the need for, and the ability to credit, actions by operator.

For probabilistic safety analysis, results can be compared to acceptance criteria for risk, where these have been specified in SSR 2/1 (Rev. 1), section 5.76. Read more →

Acceptance criteria are most commonly applied to licensing calculations, both conservative and best estimate. As discussed before, acceptance criteria are used to derive design requirements for SSC.

The range and conditions of applicability of each specific criterion have to be clearly specified. In some jurisdictions the regulatory body may approve the whole set of acceptance criteria. However, in other ones the regulatory body may not formally approve the more specific acceptance criteria but review the choices made by the applicant.