In tunnel, underground car park and industrial fires, success often turns not on the volume of water but on how close anyone can get. An unmanned vehicle moves in while the crew stays outside.
There are incidents where an interior attack fails not on skill but on justifiability: a tunnel with unclear smoke spread, an underground car park with vehicles alight, a hall containing hazardous materials or a risk of explosion, a roof structure close to collapse. The incident commander is then left with a choice between exposing personnel to a risk that cannot properly be assessed and watching from outside.
A remotely operated tracked vehicle opens a third way. It needs no breathing air and does not fail when visibility drops to zero. The operator stays outside the danger area — for comparable firefighting robots, manufacturers state radio ranges of 150 to 300 metres, and up to 2,500 metres via a network relayed from the carrier vehicle.
The second reason is more prosaic: staffing. A fire watch, an exposure-protection position or a cooling task held for hours ties up personnel who are needed elsewhere. A vehicle that holds position and directs a stream ties up one operator.
Applying water is only one of them — and in practice often not the most important.
Remotely operated monitor with variable reach and stream pattern. The vehicle holds position at the seat of the fire while the crew stays at a safe distance — for hours if need be.
Before water comes visibility. A ventilation unit pushes smoke out of a tunnel, an underground car park or a basement and makes the area passable for crews in the first place. When the Kleve fire service deployed its firefighting robot for the first time in December 2022, at a burning underground facility in Duisburg, it first cleared the smoke with its large fan; only then could crews advance to the seat of the fire.
Thermal imaging and lighting deliver a picture from inside before anyone enters: where the fire actually is, where the hot spots are, whether the structure still holds, whether someone is in the room.
Cooling vessels, protecting neighbouring buildings, containing spread — tasks that above all demand endurance, and where a vehicle never needs relieving.
Anyone procuring an unmanned firefighting vehicle should know the constraints beforehand — they determine its operational value more than reach ever does.
For interior attack there is, however, a way around the water problem: compressed air foam (CAFS). According to the technical report of the vfdb, the German fire protection association, a hose carrying wet compressed air foam is around 30 per cent compressed air by volume and therefore at least a quarter lighter than one filled with water; in large-scale tests, compressed air foam lowered smoke gas temperatures on average twice as much as water for a comparable quantity of extinguishing agent. A lighter line can be dragged further — that is precisely what makes a compact platform usable inside a building, while the large monitor stays outside on its supply line. An ultra-high-pressure water mist system is an alternative.
Platform size is therefore not a side issue: a compact platform fits into a stairwell and an underground car park, a large one carries a high-flow monitor. Which one fits depends on your buildings.