How 9-1-1 Works

What Happens When You Dial 9-1-1


Most of us expect that a professional emergency dispatcher will be there on the other end of the phone, ready to help, at a moment’s notice. As simple as the concept is the 9-1-1 system is both very clever and very sophisticated. Let’s take a look at what happens when you call.

When you dial 9-1-1:
  • The call goes first to the phone company’s database.
  • There, it finds the information that you supply when you start your service.
  • Then your call, with the information, is sent to the 9-1-1 center that serves your location.
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After 10 to 20 seconds our 9-1-1 center can send a signal to a cell phone to request its GPS coordinates. With most cellular providers we can determine the location of the cell phone within 50 feet.

Location of the Emergency


The location of the emergency is the most important piece of information we gather from every 9-1-1 call. Because there are occasional mistakes in the databases and GPS locales we answer every 9-1-1 call with the question “What is the location of your emergency?” As mentioned before it takes several seconds for the computers to verify this and it is usually much faster for us to simply verbally verify the address. After giving the address be prepared to repeat it in response to “…repeat the address / location for verification.”

Services Provided


The emergency telecommunicator answering your 9-1-1 call determines the specific services needed using a proven and efficient interview process. They immediately contact the appropriate emergency units and provide initial help if necessary via telephone instructions. This entire process is driven by a Computer Aided Dispatch (CAD) system, as your information is entered into the system the computer tracking the availability of emergency units automatically routes the information to the correct dispatchers along with its determination of which units to be dispatched.

Although the CAD system has begun the process of actually notifying emergency responders after the first few questions the emergency telecommunicator continues the interview process to gather critical information responders rely on to arrive fully prepared to efficiently and safely address the emergency situation. As more information is fed into the computer during the interview dispatchers continually update the responding emergency units via radio with more detail about the emergency.