SLA escalation at time of breach

SLA escalation at time of breach

I am wondering if there is any way to setup an SLA that will run the escalation at the time of the breach.   For example, we have a SLA indicating that response should happen within 2 hours.    We want the level 1 escalation to happen at the time of the breach but it appears you have to code an exact time to send the alert.    I wanted to populate escalate after 0 days but didn't know what to put into time.    Is it possible for the alert to happen right at the breach or are we limited to populating an exact time?