http://www.scottishambulance.com/newsdesk/acc.aspx
//The 999 operator will ask you which service you require. Your call will automatically be routed to the Ambulance Control Centre (ACC) that handles calls for your region. If there are unusually high spikes in call volumes, your call will automatically be routed to one of the other two ACCs. The technology in control rooms is seamless so that any of the three ACCs in Scotland can answer and triage your call and dispatch an ambulance to you, wherever you are.
Once you are put through to an ambulance call taker they will ask you for location details to confirm the information displayed on mapping systems. They will then ask a series of questions to establish the clinical severity of the call and categorise it for the most appropriate response. While this is happening, the dispatcher can see your location and will be tasking the nearest available ambulance. This happens simultaneously so that there is no delay in dispatching an ambulance. If the triage establishes that the call is not an emergency or does not require an ambulance response, the dispatcher may stand down the ambulance.//