Fire has a very long history with humans. Fire has both life-sustaining and life-terminating properties. We need it for cooking, warmth, and a variety of other things in our daily lives. But it can also be a destructive force in our homes and the world we live in.
However dangerous and difficult it may be to extinguish flames, they need three distinct components to ignite. Consequently, they may also be challenging to initiate!
Understanding the three components of fire helps us to manage fire by learning how to start, maintain, and put out a fire.
What Is The Fire Triangle?
The fire triangle is a fundamental paradigm for understanding the chemical mechanism necessary to ignite a fire. Fuel, heat, and oxygen are the three elements necessary to ignite a fire.
It also emphasizes the interdependence of these elements in the production and maintenance of fire and informs us that removing any of them would prevent or extinguish the fire.
The fire triangle, which investigates the physics of fire, is often used in basic fire safety teaching.
By analyzing and grasping this in more detail, it becomes much easier to appreciate the need for and details of basic fire regulations; so, let's return to the basics.
Three variables make up the fire triangle.
Oxygen
In general, oxygen is necessary for combustion (the chemical process that produces fire). Typically, this is merely the oxygen in the air.
Therefore, the air in our atmosphere is a good source of oxygen for igniting fires.
During big wildfires, an incredible amount of oxygen is taken from the air. As a result, firefighters often report feeling smothered while engulfed in scorching flames.
It is conceivable, under severe circumstances, to start a fire using substances other than oxygen. These substances are referred to as oxidizers or oxidizing agents.
Things that oxidize may undergo a similar chemical reaction to oxygen in a fire. This chemical process involves the transference of oxygen or electrons, which is responsible for the chemical reaction that causes combustion in a fire.
When oxygen is absent, such as in space, oxidizing agents are often used. Spacecraft must carry oxidizing agents for their rockets to burn.
Utilizing NOS (nitrous oxide) in drag racing vehicles is another instance of using an oxidizing material to ignite a fire.
NOS is injected into an engine of a car to increase the oxygen content during combustion. This injection enhances the engine's combustion and propels the pistons to move faster than usual.
Heat
Heat is required to start a fire. However, once a fire is lit, it often generates sufficient heat to maintain itself without the need for regular additions.
The amount of heat necessary to ignite a fire is referred to as the 'autoignition temperature.'
This stage is reached when enough molecules of vapor have been extracted from the fuel to trigger the burning of the fuel and oxygen.
It is the point in which electrons or oxygen atoms move between oxygen and its fuel source, emitting energy, heat, and light (e.g., a fire).
The 'flashpoint' is another temperature at which a material may ignite.
Nonetheless, this is the temperature at which an item exposed to an open flame, such as a match, would catch fire. It is lower than the material's autoignition temperature.
The 'fire point' is the temperature at which combustion will maintain itself for at least five seconds without additional heat. Typically, this temperature is a few degrees over the fuel's flashpoint.
Fuel
Fuel, the third and final ingredient of the fire triangle, is the fire's heart and soul. During combustion, the stored energy is released as heat and light.
Fuels for fire are distinct from other kinds of energy, such as batteries and springs, which release electrical and mechanical energy, respectively.
In contrast, these various fuels release their stored energy in the form of heat and light.
Wood is the typical kind of fuel for a fire. Since more than 2 million years ago, humans have managed wood fuel for fires.
Since the usage of coal by Persian chemists around 800 B.C., fossil fuels such as coal have been used by humans.
However, it wasn't until the Industrial Revolution in the 1700s that fossil fuels were exploited extensively.
In this age, machines converted the stored energy in fossil fuels into mechanical and electrical power using steam and combustion engines.
How Hot Can Fire Get?
The temperature of fire depends on the kind and amount of fuel as well as the oxygen or oxidizer present.
If a broad range of temperatures is wanted, a normal fire may reach between 400°F (200°C) to in excess of 6,000°F (3,300°C).
The colors of the flame may be utilized to determine the fire's temperature.
Clearly, it depends on the fuel kind. However, assuming standard burning conditions, the projected color range would be:
Violet
Violet flames are the only flames that can burn greater than 3,000°F (1,650°C).
Blue
Blue flames may reach temperatures between 2,600°F (1,400°C) and 3,000°F (1,650°C), making them one of the hottest of all flames. Few materials can withstand this degree of heat.
A standard candle flame appears blue in space. This color is not caused by a greater temperature, but by the lack of gravity, which decreases convective fluxes and avoids sooting.
White
White flames may vary from 2,400°F (1,300°C) to 2,700°F (1,500°C).
Orange/Yellow
On this flame level, temperatures fluctuate between 2,000°F (1,100°C) and 2,200°F (1,200°C).
Red
Red is the most prevalent hue, particularly during home fires. These flames will burn between 980°F (500°C) and 1,800°F (1,000°C).
What You Need To Know About Fire Control
A fire requires all three components of the fire triangle in order to burn. If one of the three elements is reduced, the fire will be weakened or extinguished.
The fire triangle is used by firefighters to design strategies to extinguish out-of-control fires.
One of the three components of the fire triangle must be destroyed in order to extinguish a fire.
If a fire runs out of fuel, it will smolder out; if it is cooled, it will lose heat and extinguish; and if it lacks oxygen, it will suffocate.
Therefore, attempts to combat and prevent fires are based on these notions. For example, fire blankets suppress a fire by depriving it of oxygen, so smothering it.
In a similar manner, fire extinguishers are intended to remove one of the three components, such as water-based extinguishers that put out fires by eliminating heat and cooling the flames.
In line with the same standards of practice, techniques for fire prevention are devised in consideration of the chemical reaction that occurs during a fire.
It is essential to take safety measures, including storing combustible materials in a secure area and keeping paper and fabric stacks away from possible heat sources.
By adhering to these fundamental fire safety guidelines, the frequency and severity of fires may be significantly reduced.
The bulk of firefighting and extinguishing equipment is designed to mitigate one of the three components of a fire.
Backburning
When a wildfire rages out of control, firefighters can often put it out. Nonetheless, there is plenty of heat, oxygen, and fuel, so the fire will continue to burn.
Backburning is a strategy that involves moving ahead of the fire and removing fuels in its path.
Typically, this entails performing controlled burns before the larger fire to reduce potential fuels. Before the arrival of the bigger, out-of-control fire, these smaller flames are doused.
There is nothing for the fire to devour when it arrives, so it stops in its tracks.
A substitute for backburning is to bulldoze and destroy trees from a short strip of land, so creating a gap in the forest that the primary fire cannot pass.
Water
A fire may be covered by water from a firefighting pump or sprinkler in order to reduce its oxygen supply.
Consider a similar scenario in which firewood is tossed into a river. In this case, water will extinguish the fire since it will no longer have access to atmospheric oxygen.
In addition to reducing a fire's temperature, water may also help in its containment.
Although not as widely used as others, there are water-based fire extinguishers, commonly known as Air Pressured Water (APW) extinguishers. However, contrary to popular belief, water is not a very efficient fire extinguisher.
There are sometimes issues with these fire extinguishers. Typically, water will flow away from a fuel source, so it does not limit the availability of oxygen for an extended period.
In addition, as grease floats on the surface of the water, grease fires will continue to burn on the water and water sprayed on these fires may cause the fire to swell and spread.
Furthermore, water is a conductor of electricity for electrical fires. Thus, the water will become electrified, providing a substantial danger of electrocution to anyone trying to extinguish the fire.
Sand
When putting out a campfire, it is usual practice to use sand and soil. By denying the fire access to the oxygen in the atmosphere, you are able to extinguish it.
However, the fire may continue to burn for some time after being buried. It is thus strongly advised to continue monitoring the fire after it has been contained.
Fire Extinguisher
Most likely, the fire extinguisher you will find in your home will be an ABC model.
These extinguishers extinguish flames of Classes A, B, and C, the most common types of household fires.
In addition, they suppress fires involving trash, wood, and paper (Class A), liquids and gases (Class B), and electrical fires that have been electrified (Class C).
The ABC fire extinguisher releases mono ammonium phosphate, a dry chemical. This chemical suffocates and oxygen-starves a fire.
Fire Blanket
A fire blanket is helpful for extinguishing small residential fires and extinguishing fire sources. Therefore, we highly suggest you keep some in strategic locations around your house.
The primary component of fire blankets is woven glass fiber fabrics with exceptional fire resistance. In addition, they are tightly woven, preventing air from passing through them.
When the fire blanket is spread evenly over the whole fire, it will provide a barrier between the flames and the oxygen, putting out the fire.
It has the same effect as putting a saucepan over a candle holder to extinguish a candle.
You may see the candle quickly splutter as it consumes the last remnants of oxygen beneath the saucer before it burns out.
How Do You Choose The Best Type Of Fire Extinguishers?
When one of the fire triangle's components are removed, the fire may be extinguished.
To extinguish a fire correctly, however, the correct extinguisher must be used.
These are the most common types of fire extinguishers used on different types of combustibles:
Water Extinguisher
Water extinguishers put out fires by eliminating the heat component of the fire triangle. They are used solely for Class A fires.
Dry Chemical Extinguisher
Dry chemical extinguishers extinguish flames by interfering with the fire triangle's chemical reaction. They are very efficient against Class A, B, and C flames.
CO2 Extinguisher
Carbon dioxide extinguishers destroy the oxygen component of the fire triangle.
In addition, they use a cold discharge to reduce the heat. They are appropriate for both Class B and Class C fires.
And since each form of fire is fueled differently, there are many types of extinguishers available.
Some extinguishers may be used on several sorts of fires, while others ban the use of specific types.
It is vital to remember that different fires need different extinguishers based on the circumstances.
And if you must use an extinguisher, keep in mind the acronym PASS: Pull the pin, Aim the nozzle or hose towards the base of the fire, Squeeze the operating lever to release the extinguishing chemical, and Sweep the nozzle from side to side until the fire is extinguished.
Frequently Asked Questions
What Are The Three Elements That Makeup Fire?
Fuel, oxygen, and heat are required. These elements constitute the fire triangle. Without these components, it is difficult to start or sustain a fire.
What Happens When All 3 Of The Fire Triangle Combine?
For a fire to start, the three components must be combined in the correct proportions. If one of the three components is removed, the fire is extinguished.
If no efforts are made to extinguish a fire, it will extinguish on its own after all of the fuel has been consumed.
What Are The Most Common Types Of Fires?
While fires may start anywhere and at any time, this section describes the four most common types. Understanding these types of fires may help you reduce or eliminate the risk of starting a fire.
Kitchen Fires
The most frequent kind of fire in the United States is the kitchen fire. The presence of heat, electricity, water, and grease in the kitchen, poses several fire risks.
Grease fires are the most common kind of kitchen fire. A grease fire is very dangerous because it may quickly spread from the stove across the kitchen and the rest of the house.
A typical cause of grease fires is leaving a frying pan on the heat unattended.
They also occur when a pan is overheated and the fat ignites during supervised cooking. Grease fires may cause catastrophic injuries and extensive property loss.
Other types of kitchen fires include oven and appliance fires. When electricity and water come into contact in the kitchen, flames may break out.
Electrical Fires
Electrical fires are caused by a number of factors, including defective equipment, outdated or broken electrical wiring, improper use of electrical outlets, and faulty circuit breakers.
Numerous older homes lack the cabling necessary to support the number of electrical appliances in use today.
Frequently, frayed or broken old wiring inside walls causes shorts and dangerous sparks.
Old breaker boxes are intended to turn off electrical power when a circuit becomes overloaded as a precaution against fire, but occasionally the connections are worn or corroded and do not trigger the breaker switch.
Lighting is another form of an electrical fire, which may be caused by improper wiring or the use of bulbs with a higher wattage than is recommended for lighting equipment.
Heater Fires
This type of fire occurs frequently during the winter. As a fire precaution, portable heaters should always be supplied with overheat-activated automatic shutoffs.
Space heaters with coils are particularly hazardous because the coils may ignite nearby combustible items. Keep space heaters at least three feet away from combustible objects.
This includes window treatments, bedding, clothing, and furniture. When leaving a room, space heaters must always be turned off.
Extension cords should not be used with space heaters, since they generate an excessive amount of electricity and might potentially start a fire.
Final Thoughts
The fire triangle is an excellent way to understand what a fire needs to burn.
The intensity of a fire may be determined by a complex combination of combustibles. However, it has just three fundamental requirements: oxygen, fuel, and heat.
This model helps us consider what is required to start and put out a fire. All contemporary firefighting techniques remove at least one element from the fire triangle.
