How Does 911 Work?

9-1-1: What's Your Emergency?

When a Mesa resident has an emergency, the computer-aided dispatch program helps 9-1-1 Operators and Dispatchers send help quickly and efficiently.

The Dispatch Process:

  1. A citizen dials 9-1-1 in an emergency situation.
  2. The caller's telephone provider automatically routes the call to the appropriate public safety agency.
  3. A 9-1-1 Operator receives the call. If the call is from a non-cellular phone, the caller's name, address and telephone number appear on a computer screen. The 9-1-1 Operator confirms that information, asks the caller about the emergency and assigns it a priority. While questioning the caller, the Operator sends the information via computer to a police or fire Dispatcher.
  4. The Dispatcher receives the information about the emergency and confirms the priority rating assigned by the 9-1-1 Operator. In Mesa, the highest priority, "E," is for life-threatening situations . The lowest priority, "5," is for report calls.
  5. Police vehicles are equipped with Global Positioning System (GPS) technology. Their locations are transmitted to the dispatch and 9-1-1 computers every 30 seconds.
  6. Location information then is transmitted to laptops in the vehicles. Each unit, represented by an icon, shows on the computer much like a tiny game piece: Police cars, bicycles, helicopters, and K-9 are represented. The icons change color depending on their status.
  7. When police units respond to an emergency, the address of the caller is displayed on a computer map in the communications center. The computer suggests the nearest vehicle. The Dispatcher, who can override the suggestion or go with it, assigns the call with the click of a mouse.
  8. The police unit receiving a call will see the address on a laptop screen. With a touch to the screen, the officer can call up a map showing the most direct route to the caller.
  9. Because house numbers generally are useless from the air, helicopters can use the system to get information such as how many houses from the corner an address is.
  10. When the emergency has been taken care of, the police officer can clear the scene via the laptop. The vehicle icon turns to dark blue on the map, and the unit is available for new calls. 

Tips for Using 911

Dial 911 only when you have a life-threatening injury or illness, or witness a serious crime in progress.

When calling 911 in an emergency:

  • Give the complete address where you need help.
  • Tell the 911 operator what the problem is -- why you need help.
  • Answer the operator's questions -- they must ask you certain questions to help the police or fire units responding to your emergency.
  • Give the 911 operator your name.
  • Remain calm and talk clearly.

Other things to know when you call 911:

  • Give your complete address, including apartment number or letter.
  • Know if the street you live on runs north and south or east and west.
  • Know what direction your home faces.
  • Know the nearest intersection.
  • Know how many houses your home is from the corner.
  • Know the streets directly around you.
  • Let the operator control the conversation.
  • Speak loud and clear, but do not scream.

Please do not call 911 and:

  • Say, "This is not an emergency, but..."
  • Ask for the Mesa Police Department's non-emergency number. The number is 480-644-2211.
  • Ask for another police department's non-emergency number. Call 411. If that police department is in another area code, call 555-1212.
  • Hang up before speaking to the 911 operator. If you do, they will call you back and a squad car may be sent to your home.
  • Report that the power is out at your home, unless it is an emergency. Call your utility service provider.
  • Ask for a weather report. Check the Internet. If your power is out, get a battery-powered radio and stay tuned to a local radio station.