In the context of LOPA, what is meant by 'event trees'?

In the context of Layer of Protection Analysis (LOPA), 'event trees' are used as a method to analyze potential accident scenarios. This analytical tool helps to evaluate the sequences of events that could lead to a specific incident, starting from an initiating event and assessing various outcomes based on different protective layers in place.

Event trees visually represent the possible consequences and pathways following an initiating event, allowing teams to identify how various factors might contribute to risk. It connects the initiating event to potential outcomes through branches, indicating whether safety measures or response strategies are successful or ineffective. This structured approach assists in quantifying risk and determining whether existing layers of protection are adequate to mitigate the hazards posed by specific scenarios.

Overall, event trees are crucial in understanding how complex interactions within a system can lead to unwanted events, thus providing valuable insights into risk management and safety assurance in various industries.