The state of alarms is affected by the state of the process, equipment, system or plant. For example, when a tank is taken out of service, the level alarms associated with the tank would be no longer used, until the tank is returned to service. This section describes ReferenceTypesthat can be used by a StateMachineto indicate that a specific Effecton Alarms caused by the transition of a StateMachine. StateMachinesthat describe the state of a process, system or equipment can vary, but an example StateMachineis provided in Annex F.