14.  Related Zones

The concept of a related zone is included.  This is in recognition that some zones will be linked to others (either physically or through related functions) and are interdependent.  These will be set out in an Appendix to the Payment Mechanism and will be specific to each facility.  

In broad terms the weighting applied to the related zone (or a percentage of it) will be taken into account when calculating of the unavailability deduction.