[en] Principles of Accident Management: Operating procedures exist for • Normal operation; • Anticipated occurrences; • Alarm Response procedures; • Accident conditions; • Emergency Operating Procedures (EOPs); • Design Basis Accident; • Limited or no fuel damage; • Severe Accident Management Guidelines (SAMGs); • Fuel damage.

[en] Conclusions: • Development of SAMG is a structured process, once strategies are selected; • Use a logic diagram to execute the various SAMG in proper order; • Develop Computational Aids to support SAMG; • Develop guidance for the TSC how to handle the SAMG, often called TSGs (Tech. Support. Gls); • Develop guidance for the MCR if the TSC is not readily available - e.g., for fast developing accidents.

[en] BWROG EPG/SAG approach: • “Symptomatic” means – A set of critical process variables; – Action levels for each variable; – Control each variable independently; • “Overrides” to coordinate two or more variables. • This allows – Flowcharted procedures. – No initiator diagnosis: Same procedure for all. • “Contingencies” to cover certain degraded conditions.

[en] FLEX objective: Establish an essentially indefinite coping capability by relying upon installed equipment, onsite portable equipment, and pre-staged offsite resources. This will enable a plant to restore and maintain its key safety functions of: core cooling; containment integrity; SFP cooling.

[en] Conclusions: • Wide experience in implementing plant specific SAMG based on the original WOG guidelines. • While generic SAMG were revised periodically, the Fukushima accident revealed additional areas requiring attention. • Following Fukushima, PWROG programs were launched to address these areas, to integrate PWR SAMG (in US) and to provide specific guidance for International Plants. • Numerous improvements, including additional guidance for the Emergency Director. • Integrating revised SAMG with other plant specific guidance and procedures provides for a comprehensive accident management capability.

[en] Conclusions: • SAMG V&V is an essential part of SAMG development and implementation. • SAMG verification is important tool to confirm that all requirements posed on SAMG package were met and guidelines are technically correct. • SAMG validation is essential activity to test developed and verified SAMG package in realistic environment before final implementation providing important feedback on future updates and personnel training.

[en] A summary of the accident consequences and analysis has been presented, in particular: • Results of a severe reactor accident: • On-site consequences; • Off-site consequence analysis; • General considerations for source term calculations; • Severe accident consequences codes; • Emergency preparedness; • Accident analysis: • Safety assessment and analysis; • Types of accident analysis; • Accident analysis methods; • Computer codes for accident analysis; • Quality of accident analysis.

[en] Conclusions: • The role of plant instrumentation is significant and has to be carefully evaluated in the process of the development of the SAMGs. • The plant instrumentation provides the vital link between: – the severe accident conditions inside the plant and – the decision making process for severe accident management activities. • Because the correct use and interpretation of instrumentation is fundamental to the successful diagnosis and management of a severe accident, instrumentation should be an integral part of severe accident training.

[en] Conclusions: • SAMG should be a living tool – Following plant modifications; – Following operating experience • Including feedback from exercises/drills; – Following changes in generic SAMG • Many changes due to F-accident; – Following safety research • Note: but first of all: complete development of SAMG! • Make SAMG part of maintenance of procedures and guidelines – Including the training; • Periodic review is helpful (may even be required), define action plan with time frame.

[en] Lessons Learned: • The regulator should require that the operator of a facility update its safety demonstration on an ongoing basis to reflect changes in the status of the facility. • Regulatory independence, competence, strong legislative authority and adequate resources, including qualified personnel, are essential in order to perform the required regulatory functions • The regulatory body needs to review and inspect the safety of a facility throughout its lifetime.