[otrs] Escalation question

A question about escalations: I'm new to the OTRS system and I was wondering is there any way for me to setup up a system of tiered escalation notifications to multiple agents? Ex. When a ticket reaches 50% escalation time automatically notify agent X, at 70% automatically notify agent Y, and at 90% notify agent Z. I've been trying to set this up for a while now but just can't seem to figure it out. Any help would be much appreciated.