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DEFENCE IN DEPTH
Defence in depth: reactors

TYPES OF EVENTS: AN EVENT WITH AN INITIATOR

 

We mentioned earlier that there are two types of events that we need to rate. The first part of the methodology is being clear which of the two have occurred. This is the first type -

An event with an initiator, in this case loss of coolant.

An initiator has definitely occurred and it is possible that there have also been some failures in safety systems.
Another well known initiator would be loss of off-site power.