Fire department maps (showing admin boundaries between where each dept is responsible) is not too bad, but maps for "within" a fire department can get a little tricky. You see, every address is mapped to a list of engines, trucks (ladders), chiefs, brush rigs, etc. IN ORDER by which is closest (by real road time, not as the crow flies).
Dispatch matches the type of assignment (x engines, y trucks, z chiefs) to the "available" list (excluding those that are out of service) and "fills" the assignment.
About the only way you can do a "district" map for a fire department is to map the 1st due engines - they're typically 1 per station. You'd need a second map for 1st due truck, with larger areas (trucks are typically about 1:3 to engines) and a third for chiefs, a 4th for brush trucks, etc.
To go beyond 1st due, you need a card file or a computer. In the old days, they used "run cards" - every address was mapped to a "box" (in the old days, the pull station on the closest corner) and every box had the entire list of of apparatus, by type, in order they were "due" at that box. Dispatch then read down the list, skipping those that were already out on other assignments, until they'd "filled the box". A second alarm worked the same way, just read further down the list.
Now, most big departments use computer assisted dispatch, but it works the same way - just uses a database to keep the lists, and the computer remembers who's available.
