As a rural EMT cadet in Aiken, South Carolina, I have begun to see how much our emergency medical system depends not only on county ambulances, but also on smaller services working behind the scenes. On a busy day, a county can reach what EMS calls “status zero,” meaning no county ambulance is immediately available for another call. At the same time, a nonprofit or private EMS service may have an ambulance only a few miles away with a crew ready…