04/20/23 1

Lisa Hoffmann, Deputy Director

San Francisco Department of Emergency Management

Division of Emergency Communications

04/20/23 2

Wireless E9-1-1 Technology

•How does wireless 9-1-1 work?•Where is my call answered?•Does 9-1-1 automatically know where I am?

04/20/23 3

04/20/23 4

During the 1990s Cell Phone Usage Boomed

• Inexpensive Phones• Increase in Wireless

Service Providers• Competitive Rates• Expanded Coverage areas• Cellular Subscribers grew

from 16 million in 1994 to 180 million in 2004

Source: Cellular Telecommunications and Internet Association

0

50

100

150

200

Cellular

Users (in

millions)

1994

2004

5

Since the 1980s, Wireless 9-1-1 Calls have been Routed to the CHP

• Bay Area Wireless calls are Routed to the CHP Office in Vallejo if the caller is near or on a freeway.

• Is that a problem in SF?• SF is bisected throughout

the city by freeways. Why can’t SF DEM receive those 9-1-1 calls?

04/20/23 6

Locating the Caller

• The vast majority of callers will know their location.

• In some instances a caller may be lost or under duress, in these cases, accurate location information is critical.

04/20/23 7

Paul FaheyDirector of External Affairs

Tiffany HowardRegional Account Manager

PlantCML

04/20/23 8

Questions ?