Do firefighters put out controlled fires with water as well?
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Controlled or not different kinds of fires may require different materials to put them out. More often that not though water is what they will use unless they have reason not to (size of the fire, source of the fire, etc…some things water will not put out well…e.g. when planes are on fire leaking jet fuel they use foam).
Presumably a controlled fire is controlled and approved by the fire department. But if it needs putting out see the above.
I’ve seen large water trucks lined up near a defensible line of a wildfire which I assume were used for fighting, just as I’ve seen helicopters taking water from our local lake and heading back to a wildfire.
A controlled burn is used in natural areas, whether grasslands or forests. It can be used to kill off invasive species so that normal-for-that-habitat grasses/trees can grow or to remove excess fuel (dead leaves, trees, etc) from a potential real fire. Depending upon what you’re burning & where it is / what’s around it, it might just burn itself out when it runs out of fuel or it might need to be put out when it reaches the limits of what they want burned.
A controlled burn is not necessarily synonymous with a training burn. One fire can serve both purposes but frequently they have separate objectives.
Water comes from one of two sources - hydrants or natural (lakes/pond, river/stream) & is free (have you ever seen a meter on a hydrant?) Yes, you might need a tanker to get it from the source to where you want to use it but filling that tanker shouldn’t cost anything. Dirt is free, too; one could create a fire break / bury it with a bulldozer. Foam & fire retardant cost money. Yes, they may use a controlled burn to also teach a new crew how to drop fire retardant but I’d suspect a controlled burn to only use water to put it out, if necessary.
I was a volunteer firefighter years ago; for a controlled grassland/cropland burn, or a controlled building burn, we used the same trucks and water as for any other standard fire situation.
Could we have some more clarification on what you’re asking about? What sort of controlled fire do you mean? Are you assuming that firefighters want to put it out and are asking how, or are you asking whether they would attempt to put it out at all?
IAAFF (not the IAFF, that’s the union, which is different).
If it’s a true controlled burn (used to reduce undergrowth), it should be timed so that mother nature finishes it off with some rain.
Parallel to that, before the burn is started, a fire break is created either by clearing space around the defined perimeter of the burn area down to mineral soil, or by applying water and wetting the area to stop the fire when it reaches that point.
The fire crews conducting the burn will focus on the edges and usually let rain take care of the middle. It really is both a science and an art to conduct a burn, with the primary rule being don’t do controlled burns in droughts (a lesson that isn’t always followed).