In New Jersey, Emergency Medical Service agencies are licensed by the state to respond to 911 calls in their area of responsibility. Each agency must schedule sufficient capacity to handle expected 911 calls at all times of day or night (24/7). Agencies use a variety of models to estimate required capacity, but they rarely attempt to stress test their capacity by varying call volume or testing the effect on call duration if the nearest hospital emergency department suddenly shuts down – resulting in much longer transport times per ambulance. This project provides a simulation tool, using actual agency data, to simulate required capacity or degradation in response times, if the nearest hospital ER closes.