The PSA activities for the ANPP was initiated in 2002. The NRSC also established the Risk Assessment Group (RAG), which plays a key role in the PSA activities for the ANPP. The main activities of RAG are:

• PSA model development,
• PSA model application, and risk-informed decision making,
• time-dependent reliability analysis (ageing PSA),
• development of national regulations in the field of nuclear safety,
• PSA training, and
• international co-operation.

The RAG is actively involved in the development of the ANPP Unit 2 level 1 PSA models for the following initiators:

• internal events,
• internal fires, and
• external hazards (excluding seismic events).

The RAG continuously updates the mentioned PSA models so that to assure their applicability for safety-related decision making.

Special attention is paid to the development of the RAG’s capabilities in the field of fire simulation and fire impact analyses. Currently the NRSC works with two computer codes devoted to fire simulation – CFAST and SYLVIA. CFAST code is used extensively for the fire PSA analysis, whereas the SYLVIA code is currently used for modeling of ventilation systems for critical compartments, as well as for the CFAST.