House fires can start spontaneously, to control these lethal flames it is best to target them when they are at their weakest.
knowing them and acting quickly can save a lot of damage. Here at firefightertools.co we believe that prevention and knowledge are key, therefore in this article, we will go through the basic stages of fire and how you can control the fire if it gets out of hand.
Stages of fire:
So to start off fire has 4 distinct stages: the first one is the incipient phase in which the fire is ignited. The growth stage is up next in which it starts to grow rapidly. This phase is succeeded by the fully developed phase in which the flame (as the name suggests) is at its peak and lastly comes the decay stage, in which it dies down and is ultimately extinguished.
But there is a lot more to this than just this so let’s take an in-depth overview of what these stages of fire mean for house fires and how they can be prevented.
Let’s start off by discussing how you can identify the incipient stage. As we’ve described above, in the incipient stage the fire is just starting. The fire can either be extinguished or it can grow to produce a catastrophic house fire.
In this stage, smoke begins to rise but not to the point that it reduces the visibility of the area.
It is just enough for people to see it. The fire detectors should immediately identify the smoke and should go off sounding the alarm. Since it is just the beginning of the fire, it can be controlled quite effectively in this stage, so now is the best time to extinguish it.
If you see a fire in this stage then you can try to extinguish it yourself but be extra careful when you do. A fire extinguisher would surely come in handy in a situation like this.
Just so that you get a clearer picture of what an incipient fire would look like, you can picture a small fire in your lawn or your backyard. Or a stove catching fire.
The most dangerous part of a house fire and certainly the most short-lived can be the growth stage. In this stage, the heat produced from the fire is so hot that it makes the nearby surrounding catch fire.
At this stage it is vital that all individuals from the building are evacuated immediately, the building is in danger of collapsing. The biggest and most frightening part about the growth stage is that it is very short-lived and usually ends in a bang sometimes referred to as a flashover event.
So before understanding what flashover is, let’s look at what a flashpoint is. Well to put it simply, the flashpoint is the temperature at which a substance can ignite itself spontaneously or in other words, it ignites automatically.
Even if there is no direct form of fuel in the room, most materials can act as fuel for the fire if their flashpoint temperature is reached. When a temperature of about 1100 degrees Fahrenheit is reached, most objects in the room ignite simultaneously releasing huge amounts of energy and light, hence the name flashover.
Other phenomena such as backdraft can also occur, in which it may appear that the fire is in its decay stage. But just as a door is opened or a window an explosion occurs. The reason behind this phenomenon is the fact that the fire was dying because the oxygen in the room was depleting and when the door was opened oxygen came rushing in which was instantly ignited and caused an explosion.
To avoid this, firefighters check the ventilation of the area which is burning, this is part of their protocol.
One very important thing to consider is the fact a flashover is actually not a stage but can be considered a transition. When the fire progresses to the next stage known as the fully developed stage a flashover event may occur during the transition period.
In this stage the fire has reached its peak, the building may be considered too dangerous for even well-trained firefighters so they may try to control the fire from a distance.
Here the fire is at a scorching high temperature. After this stage, the fire will slowly begin its decline and enter a decay stage. But as we’ve described before there are some situations in which it may come back, like in the case of a backdraft.
This is the final stage of a fire, in this stage, the fire has spread to all the areas that it possibly could. It is now slowly decaying and decreasing in intensity.
It is important to note that a fire will enter this stage if the fuel runs out, or the supply of oxygen is limited. If new fuel is added the fire can very well be reignited.
This stage may take hours, days, or even weeks to finish. As fuel such as wood stumps can burn for a considerably long time if not intervened. In the case of a forest fire, this is a critical stage as the fire can easily spread to other surrounding areas. The quicker the flame dies down the lower the chances of it reigniting.
Important things to consider:
- It is not always necessary that the entire house is on the same stage of the fire, fires can change quite rapidly, and depending on the materials in the room can evolve rapidly or not at all. In a building, it is possible that some rooms have reached the fully developed phase whereas in others there is no sign of fire at all. So when inspecting a building each room is to be as a separate house fire scenario.
- Malfunctions can change the outcomes or the probabilities of fire and hence have a lot to do with the dynamics of the fire itself. Let’s take an example, a window gets sealed or a door gets jammed, in such a scenario the room can run out oxygen pretty quickly, and in such a case opening the said door can be the cause of a backdraft.
- For firefighters, it is sometimes useful to know the layout of the building, in house fires a tactical approach like a pre-planned approach to the problem can be difficult as the time is usually short and the variations are higher. For example, a larger building that has been burning for quite some time, this method can be an effective tool to deal with fires in a tactical way.
- Also smoke may not be the best indicator of the stages of fire or it’s ferocity, white smoke was previously thought of as a less meaningful form of smoke but that is certainly not the case. Each situation should be assessed individually because white smoke can also originate from different sources such as rubbers. If we run with the preconception that white smoke is not as bad then things could turn sideways pretty quick.