Severe accident mitigation technology was developed and evaluated for a small integral reactor of SMART. The containment pressure and hydrogen behavior were analyzed using MELCOR computer code (Sandia National Laboratory, 2018) in the SBO (Station Black Out) sequence, which was selected from PSA (Probabilistic Safety Assessment) results for the SMART. The severe accident mitigation technology to improve the SMART safety include reactor vessel depressurization using the ADS (Automatic Depressurization System) to prevent DCH (Direct Containment Heating) in case of a reactor vessel failure, a reactor cavity flooding using the CFS (Cavity Flooding System) with the IRWST (In-containment Refueling Water Storage Tank) for the IVR-ERVC (In-Vessel corium Retention through External Reactor Vessel Cooling) to prevent the reactor vessel failure, and a hydrogen control system of PARs (Passive Autocatalytic Recombiners) to remove hazards from hydrogen combustion considering the amount of hydrogen to be generated by 100% fuel cladding oxidation. The MELCOR results showed that the containment pressures during the SBO sequence was below the design pressure, which meant that the containment integrity is maintained during a severe accident in the SMART. The hydrogen mole fraction of the containment was much lower than the hydrogen safety criteria of 10 vol%, which meant that the possibility of the hydrogen burn in the containment was negligible. For this reason, it could be concluded that the hydrogen was controlled by the hydrogen moving path and the hydrogen control system of PARs in the SBO sequence of the SMART.

开发了严重事故缓解技术，并对SMART小型整体反应堆进行了评估。使用MELCOR计算机代码（Sandia国家实验室，2018）以SBO（站点停电）顺序分析安全壳压力和氢气行为，该顺序选自SMART的PSA（概率安全评估）结果。旨在提高SMART安全性的严重事故缓解技术包括：在反应堆容器发生故障的情况下，使用ADS（自动降压系统）以防止DCH（直接安全壳加热）对反应堆容器进行降压；使用CFS（腔体溢流系统）对反应堆腔体进行溢流与用于IVR-ERVC（通过外部反应堆容器冷却的容器内钙保留）的IRWST（容器内加油储水罐）一起使用，以防止反应堆容器故障，以及考虑到100％燃料包壳氧化产生的氢气量的PARs（被动自催化重组器）的氢气控制系统，以消除氢气燃烧的危害。MELCOR结果表明，在SBO顺序中，安全壳压力低于设计压力，这意味着在SMART发生严重事故期间，安全壳的完整性得以保持。安全壳中的氢气摩尔分数远低于氢气安全标准10 vol％，这意味着安全壳中氢气燃烧的可能性可以忽略不计。因此，可以得出结论，氢是由SMART的SBO序列中的氢的移动路径和PAR的氢控制系统控制的。