There are three zone dependency functions available:
Type A - If there is an alarm from a detector, the panel will look for a confirmatory alarm from the same or another detector in the same zone before a full alarm is established. If there is no confirmatory alarm, the first alarm will automatically reset.
Type B - As type A except the confirmatory signal must be from another detector in the same zone.
Type C - As type A except the confirmatory signal may also be from another zone, and the first alarm will not automatically reset.
This gives the ability to isolate a zone temporarily e.g. if there are building works being carried out and there is a risk of dust or smoke, the zone can be temporarily isolated to prevent false alarms.