Anybody here ever work as an emergency dispatcher?

[Bryan]

The city I live in is advertising for competitive applications for several vacancies for emergency dispatchers. I decided to apply because I've spent the last four years working in contact centers, and I think I've built up a decent tolerance for handling four or five things at once while getting yelled at, plus the city will train me and the starting pay (with full benefits) would be a massive step up from my current status.

Just offhand, if anybody has worked in this field,

-What should I be studying in aid of getting a position like this?
-What should I know beforehand? Is there anything you wish people had told you in advance before taking the job?
-What should I talk about in the interviews?

Any help or details would be greatly appreciated. Thanks!