Probabilistic safety assessments (PSAs) are recognized as an important tool for assessing the level of safety for nuclear power plants (NPPs). In particular, the Level 2 PSA for NPPs provides key insights about the potential radioactive releases that could affect the workers, the public and the environment following a severe accident. The purpose of this Specific Safety Guide is to provide an updated internationally accepted methodology for the development of a high-quality Level 2 PSA for NPPs. The revised Specific Safety Guide is intended for use by designers, operating organizations, technical support organizations and regulatory bodies in the development, application and independent review of Level 2 PSAs. The revised Safety Guide is also intended for use in connection with both the review for authorization (licensing) of the construction and the operation of new NPPs and the safety re-evaluation of existing NPPs during periodic safety reviews and modifications.