What Is 9-1-1?

9-1-1 is the designated 3-digit number for accessing emergency services in the United States. Using this single, 3-digit phone number a caller can request law enforcement, fire response, or emergency medical services almost anywhere in the country.

In Colorado, this service is available in every county and in every city - anywhere telephone service exists.

Enhanced 9-1-1 (E9-1-1) refers to 9-1-1 service with "selective routing." In an E9-1-1 system, 9-1-1 calls are routed to a "selective router," which determines which 9-1-1 center to send calls to based on information in a tabular database. This allows for better routing and alternate routing of 9-1-1 calls than is available in basic 9-1-1.

More commonly, though, E9-1-1 is associated with location information. After the 9-1-1 call is delivered to the call center, automated equipment at the call center queries a separate address database to retrieve a location for the call. This location can be static, as it is with a call from a landline phone or most Voice-over-Internet-Protocol (VoIP) phones, or it can be dynamic, changing with the caller's actual location, as it would with a wireless phone.

Every 9-1-1 center in the state of Colorado has E9-1-1. Only one county is unable to receive location information associated with wireless devices.

If you're calling from a phone that is associated with a specific location, like a landline phone or most Voice-over-Internet-Protocol (VoIP) phones, your service location is stored in a database that is queried by your phone number when you call 9-1-1.

For wireless phones, 9-1-1 centers rely on your wireless service provider to provide your location information. Your wireless service provider determines your location using a number of different methods, including Geographic Position System satellites and cell tower location, and some providers can also make use of other sensors in your phone to help pinpoint your location.

9-1-1 location information is not always accurate or precise, especially for wireless devices. For this reason, most 9-1-1 centers will not rely on your service provider's location information unless they are unable to verify your location with you verbally.

Next Generation 9-1-1 is a 9-1-1 service that delivers 9-1-1 calls and other data to 9-1-1 centers over a digital, protected Internet Protocol network. There are a number of benefits to NG9-1-1 over a traditional, or "legacy" 9-1-1 network. Immediate benefits include faster call delivery to the 9-1-1 center, more dynamic routing of 9-1-1 calls, faster delivery of location information, and a more resilient network. 

The long-term benefits of NG9-1-1 include the ability to send other types of data to 9-1-1 call centers, which could include text-to-911, pictures, medical data, automatic crash notification data, and more.

Colorado does not yet have a Next Generation 9-1-1 network, but we have taken the first step toward implementation of NG9-1-1. 9-1-1 centers in Colorado are now connected to a statewide IP-based 9-1-1 call delivery network, called an Emergency Services IP Network, or ESInet.