The system is a dynamic layered response system. An EMS response to an emergency begins with a telephone call to 9-1-1. Calls are transferred from a primary call taker to emergency medical call taker who gathers information from the caller, gives instructions to the caller, and determines what types of emergency personnel to send. For very serious and life-threatening emergencies firefighters trained in basic life support and paramedics trained in advanced life support respond simultaneously. Paramedics transport patients in critical condition. For less severe emergencies only firefighters will be dispatched. Basic life support personnel from either a fire department or private ambulance company transport non-critical patients.