Top event

{
  "id": "MLC-T-NUC-000514",
  "term": "Top event",
  "field": "Nuclear energy and radiation",
  "definition": "The events across the top of the event tree, which graphically represent the systems needed to keep the plant in a safe state following an initiating event (i.e., a challenge to plant operation). A top event is the starting point of the fault tree, which identifies all of the pathways that lead to a system failure. For additional information, see Probabilistic Risk Assessment.",
  "references": [
    "NRC Glossary"
  ],
  "url": "https://mlchart.com/terminology/nuclear/top-event/"
}