When using a wired phone, the telephone company is responsible for routing the call to the correct Public Safety Answering Point (PSAP). For example, if you live in Dauphin County and dial 9-1-1 you will get Dauphin County 's Public Safety Answering Point (PSAP), which is Dauphin County Emergency Communications Center (ECC). If you live in the City of Harrisburg , your hard wire 9-1-1 call will be routed to the City of Harrisburg Communications Center.

Enhanced 9-1-1 systems provide what is called ANI/ALI (Automatic Number Identification/Automatic Location Identification). This feature provides the 9-1-1 telecommunicator with the type of phone line being used, the number where the call originated from, and the name and address that is attached to the phone number's account. The ANI/ALI information is provided by the phone company and is subject to change without notice. For this reason, the telecommunicator must ALWAYS verify the location and phone number. When reporting an emergency it is imperative to know where you are and the number you are calling from.

In recent years , wireless phone usage has been increasing in leaps and bounds. In fact, over 50% of the 9-1-1 calls that come into the Dauphin County PSAP originate from wireless phones.

In 2004, the Dauphin County Emergency Management Agency, in cooperation with all the wireless carriers providing service in Dauphin County , was able to deploy Wireless Phase 2 throughout the County. This means that if you make a 9-1-1 call from a wireless phone which is properly equipped by your carrier, the Dauphin County PSAP will receive the following information :

• Your wireless telephone number
• Your wireless carrier's name
• Date and time of the call
• Longitude and Latitude of the wireless phone

After receiving the longitude and latitude information , the PSAP computer equipment plots the caller's location within a matter of feet on the Computer Aided Dispatch (CAD) mapping system. The telecommunicator also has the capability of following a caller by sending a retransmit signal during an established call; thus providing a change in the longitude and latitude information displayed on our CAD system. While this technology is constantly improving, there are still some limitations that prevent the wireless phone from providing a good location. Being inside a building, the type of terrain near the wireless phone, and weak signal strength may contribute to poor reception of information. Because of these variables, it will always be important to know your location when calling 9-1-1, regardless of what type of phone system you are using.