Final answer:
911 calls are routed to the correct PSAP based on the caller's location, using landline databases or mobile location technologies such as GPS or cell tower triangulation.
Step-by-step explanation:
911 calls are selectively routed to the correct Public Safety Answering Point (PSAP) based on the caller's location. When a 911 call is made, the calling device's location information is used to determine which PSAP is best equipped to respond to the emergency. This process leverages the Enhanced 911 system (E911), which enhances the basic 911 service by providing additional critical information.
For landline calls, the location data typically comes from a fixed address database. In contrast, for mobile calls, the location is calculated using various technologies such as GPS or triangulation from cell towers. Selective routing ensures that callers are quickly connected to a PSAP that can dispatch the appropriate emergency services, which is vital for saving lives and property during emergencies.