LA County 911 System
The local 911 system has both city and county, cell and landline, fire, medical and police components. Cellphone calls are initially directed to California Highway Patrol. Once a cell call is received, the nearest cellphone tower is immediately in view by the operator. All landline calls are directed to local law enforcement (LAPD or Sheriff). Fire, medical and police issues are routed differently. LA County Fire uses contract ambulance services. LA City Fire uses their own vehicles. Calls directed to LA County Fire initially go to a call taker, then a dispatcher, then a radio operator. In the event of a larger disaster, there are mutual aid agreements in place. A computer system, Computer-Aided Dispatch (CAD) automates the process.
In the county there are 32 fire departments that provide 911 emergency medical services. LA County covers the unincorporated areas and then contracts with many of the cities to provide their fire and EMS services for that city. The remaining 31 fire departments provide services to their specific City (i.e. LA City Fire Department, Beverly Hills Fire Department, etc.). The transportation component is another issue and the provider (fire department) can choose to do their own transports or contract with a private ambulance company to do the transport component. The Los Angeles County Department of Health Services Ambulance Services is not a 911 system provider. They only do inter-facility transport of County responsible patients. The city and county of LA have separate dispatch facilities.
Coordination of 911 surveillance
Done by City and County Fire and EMS (under Dept of Health Services)
Dispatch centers take the calls (will elaborate)
Cell phone calls can be triangulated to determine position and go to California Highway Patrol
Landline calls go to the nearest dispatch center.