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DEFENCE IN DEPTH
Defence in depth: facilities

FIGURE 10, PAGE 151 CONTINUED

 

There is one further question that we need to address and it is shown here. (Again, this is taken from figure 10, page 151 of the Manual)

Obviously, the length of time that a component or system is unavailable affects the risk. However, INES does not generally aim to take this into account except where the period is very short.

The Manual explains that 'very short' means something like a couple of hours for a component with a test interval of a month.