Fire Department.
What happens when you call 9-1-1.

Maricopa Fire Department is dispatched by Phoenix Fire Department.

Calling the Fire Department
Phoenix has an enhanced 9-1-1 system, the largest in the world. This means that the 9-1-1 operator (referred to as the "dispatcher") can identify through the system's computer, the phone number and address of the calling party. This assists in timely dispatching of police or fire units to the emergency scene.

Common fire emergencies include structure fires, brush fires, and car fires. Common medical emergencies include heart attack, car accidents, respiratory difficulty, seizures and ill persons.
When a call is received by the 9-1-1 PSAP (Public Safety Answering Point), they will say, "What is your emergency, police, fire or medical?" The caller should tell the dispatcher which type of emergency they are reporting or give a description of the problem, allowing the dispatcher to decide how to route the call. In Phoenix, the 9-1-1 operator is actually a police dispatcher assigned to process in-coming emergency calls.

If it is a police matter, they will stay on the line and take information. If it is a fire or medical emergency, they will tell the caller to stay on the line and will transfer the call to the fire department. The phone line will ring again. The fire department dispatcher will come on the line and ask the caller if there is a fire or medical emergency. A proper address and phone number will be asked for to verify the 9-1-1 information.

The dispatcher will begin to dispatch emergency units immediately. If it is a medical emergency, the dispatcher then will transfer the caller to the medic dispatcher sitting nearby. The medic dispatcher is specially trained for medical emergencies to provide self-help instructions to the caller while units are en route.

Maricopa Fire Department fire engines, ladder trucks and SouthWest ambulances are dispatched according to the nature of the call. The closest unit will be sent to ensure that help arrives as soon as possible. It also means that more than one fire unit may be sent to the scene.
All Maricopa firefighters receive medical training and, at a minimum, are EMTs (Emergency Medical Technicians). Certain firefighters receive additional training as paramedics. They are capable of providing advanced life-support treatment including IVs, drug therapy and cardiac monitoring.

Whenever a person calls 9-1-1, their message needs to be clear. They also need to stay on the phone until the person in the 9-1-1 center has released them from the conversation.
Try to stay calm. State what kind of emergency it is - fire, car accident, heart attack, etc. Then tell the dispatcher where the incident is.