We have a fire station three blocks south and they often run north on a 3 lane one way street which has a T intersection with a two way street with a light. Further north it is two way, but at that light heading north, traffic often builds up a bit and the trucks can't get through if the light is red and cars sit there. They lean on their horn and eventually the light turns green or maybe the cars pull through the red light and out of the way.
It will get more interesting in a couple years because they plan to turn the 3 lanes into 2 lanes with a bike lane. Ideally the trucks could flip the traffic lights as needed by radio. One of the trucks is a large hook and ladder deal with a driver in the rear of it steering the back end.