Airport emergency services are presumably trained in this, but since a plane cannot stop easily (or not at all on takeoff after V1), I seem to remember the general rule is that even emergency vehicles with lights and sirens on give way to planes, and don't enter runways without permission from the tower.

In the audio released by the BBC, the fire truck DID get permission from the tower to cross something, I can't tell if it was the runway in question. However, to cross the red runway lights if lit, you normally need that spelled out too something like "truck one, cross four delta, cross red lights". This did not happen on the BBC audio, which could mean one of many things.

From the FAA’s site [1] on RWSL:

> If an Air Traffic Control clearance is in conflict with the Runway Entrance Lights, do not cross over the red lights. Contact Air Traffic Control and advise that you are stopped due to red lights. (ex.: "Orlando Ground, Ops 2 is holding short of runway 36 Left at Echo due to red lights").

Airports are highly controlled environments unlike typical motor vehicle roadways and generally the same rules apply for aircraft, vehicles, and equipment on airport surface movement areas. From all sources I can find, if the RWSLs were working they should have been red and nobody should have entered the runway without further clarification from ATC.

[1] https://www.faa.gov/air_traffic/technology/rwsl

All vehicles can override/ignore warning devices. Doesn't make it right. Emergency vehicles should not override/ignore train or plane crossings. Trains and Planes don't care about flashing lights. Crossing an active runway requires clearance for safety.

In this case, from the available information, the drivers of the fire truck thought they were cleared, and proceeded to cross while a plane was cleared to land. I'm not familiar with ATC ground radio to know if they were actually cleared or not, but it seems clear that that the drivers thought they were cleared.

Investigation reports will give us more details.