Colors have some inherit meaning, but are also assigned as various things.
Fire, Dirty, Blood, Cops?, Hospital.
Red: dirty or dangerous
Money, Financial, Environment.
Green: clean or financial
Water, Fire Department, Police, Emergency Services.
Blue: resource or service
Residential, Commercial, Industrial, Banks, Mining, Airports, Ports, Roads (and Highways), Power Lines.
Red is dirty. Green is clean. Blue is resources. ??
R+B = Magenta, Industry (dirty+resource)
R+G = Yellow, Commercial (dangerous + financial)
G+B = Teal, Industrial (financial + resource)
R+B = Magenta, Residential (dangerous/dirty + resource?)