Firefighter (NPC)
The Fire Department will respond to a fire alarm when there is a fire, but if you don't have an alarm, it is best to phone them up quickly. If you prank call them when there is no fire, you will get a §500 fine. The Fire Department will come in a fire engine (The Sims 2 or later) and will carry a large fire extinguisher and a tank on his/her back. Once they start to extinguish the fire, build and buy mode will be available. Firefighter outfits are available through the BoolProp testingcheatsenabled cheat. Most of the time, the firefighter will be male, but she may be a female occasionally.
In the trailer for The Sims 3: Ambitions, it shows Firefighters scrambling in what seems to be the fire department, showing firefighters getting changed, sliding down poles and it also shows a fire-truck. As Firefighter is a new career in Ambitions, this is presumably the workplace for the career, but this could simply be specially made for the trailer.