Available in NiagaraAX-3.5 and later, the On Call Service is a customization of the alarm service that allows you to send alarm notifications to users based on a priority list (“Contact List”). This service initiates an email (or text message) notification for designated alarms, sending the notification sequentially, as alarms escalate, to users based on their assigned priority. The OnCallService component is available in the onCall module. Also see About the On Call Service.