A fire is three things meeting. Something to burn: the fuel. Enough heat to start it. And air, because fire breathes oxygen like we do. Take any one of the three away and the fire goes out. Every way of fighting a fire, and every way of preventing one, is one of those three removals.
Watertakes the heat
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A blankettakes the air
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Cardboard movedtakes the fuel
Water on a wood fire takes the heat away. A fire blanket over a burning pan takes the air away. Clearing the cardboard from beside the heater takes the fuel away before there is a fire at all. The fire does not care which leg you cut.
A fire blanket is laid over a pan of burning oil. Tap the thing it takes away.
Tap the part of the picture that answers it.
Heat
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Fuel
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Air
Air
Right. The blanket seals the pan, and the fire uses up the oxygen under it in seconds. The oil is still hot and still there; it has nothing to breathe.
Heat
Not yet. The oil stays hot under the blanket for a long while, which is why the pan is left covered. The blanket does not cool it; it smothers it.
Fuel
Not yet. The oil is still in the pan. Nothing has been removed; the blanket works by keeping the air from reaching it.
Flameswhat people fear
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Smoke and gasthe most common killer
England, year to March 2025.
People picture flames, and the flames are not what kills most. In England in the year to March 2025, 271 people died in fires, and the most common known cause was being overcome by smoke and gas, not burns. A small flame can become a major fire in under half a minute, and a room can be deadly within two.
Move the control to change how much oxygen is in the air. Normal air is about 21 per cent. The effects are the rough figures used in fire and safety training.
The fireburns freely
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A personfine; this is normal air
21% oxygenAt 21 per cent oxygen, the fire burns freely. A person in that air is fine; this is normal air.
The fireburns freely
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A personfine, though below 19.5 counts as low for people at work
19% oxygenAt 19 per cent oxygen, the fire burns freely. A person in that air is fine, though below 19.5 counts as low for people at work.
The fireburns, but weaker
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A personbreathing faster and thinking a little slower
17% oxygenAt 17 per cent oxygen, the fire burns, but weaker. A person in that air is breathing faster and thinking a little slower.
The firemost fires go out
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A personconfused and unsteady, and in danger
15% oxygenAt 15 per cent oxygen, most ordinary fires go out. A person in that air is confused and unsteady, and in danger.
The fireout
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A personunconscious within minutes
12% oxygenAt 12 per cent oxygen, the fire is out. A person in that air is unconscious within minutes.
The fire goes out somewhere around 15 per cent oxygen. What is a person doing in that air?
Breathing a little faster, nothing more.
Not yet. A little faster is 17 per cent. At 15 the brain is short of oxygen and judgement goes, which is the part that stops people leaving.
Already in danger: confused, unsteady, close to fainting.
Right. People fail before fires do. By the time the air is too thin to burn, it has been too thin for a person for a while, which is why a smoke-filled room is lethal long before the flames reach it.
Fine. If the fire cannot burn, the air must be safe.
Not yet. It runs the other way. A person is in trouble below about 19.5 per cent; the fire holds on down to about 15. The fire is tougher than you are.
Move the control.
Each card is something a workplace does about fire. Which of the three things does it take away?
One card at a time. Tap the pile it belongs to.
Card 1 of 6
Sprinklers in the ceiling.
A fire blanket in the kitchen.
Bins kept away from the back wall of the building.
Solvents stored in a metal cabinet.
A fire door kept shut.
Cold water poured on a wood fire.
Sprinklers in the ceiling. → Heat
Not yet. Heat. Water cools what is burning below the point where it can keep burning, and wets what has not caught yet.
A fire blanket in the kitchen. → Air
Not yet. Air. The blanket seals the burning thing from the oxygen around it, and the fire uses up what is trapped in seconds.
Bins kept away from the back wall of the building. → Fuel
Not yet. Fuel. A bin against a wall is fuel placed next to the thing you least want to burn; moving it removes the fuel before any fire.
Solvents stored in a metal cabinet. → Fuel
Not yet. Fuel. The solvents are the fuel; the cabinet keeps them from the heat and from each other, so a small fire does not find a big fuel.
A fire door kept shut. → Air
Not yet. Air, and spread. A shut door starves a room's fire of the fresh air in the corridor, and holds back the smoke that would kill people on the other side.
Cold water poured on a wood fire. → Heat
Not yet. Heat. The water takes heat from the wood faster than the fire can make it, and the wood drops below the temperature it needs.
Heatcool it
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Fuelremove it
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Airsmother it
Right. Cooling takes the heat. Removing, storing and separating take the fuel. Smothering and shutting doors take the air. Every answer to fire is one of the three, and the best ones act before the fire starts.
Alarm→Two ways out→Doors open, unlocked→Meet and count→Practise
The smoke comes first and the time is short, so getting out is planned in advance. An alarm everyone can hear. Two ways out, so one blocked route does not trap a floor. Routes kept clear, doors that open outward and are never locked. A place to meet, and a count. Then a practice, before any smoke.
Fire doorwedged open
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So what?
A fire door in an empty corridor is wedged open to let a breeze through. Why is that a risk, when nobody is in the corridor?
It is not a risk. An empty corridor has nobody to harm.
Not yet. The corridor is empty until the alarm sounds. Then it is the busiest place in the building, and the wedge has already decided what fills it.
Only because the breeze feeds the fire with air.
Not yet. Air to the fire is part of it. The bigger harm is the smoke travelling the other way, into the route people need to leave by.
The door's job is to hold smoke and fire back when there is a fire. Open, it lets them into the escape route for everyone on the other side.
Right. Nobody is in the corridor now. In a fire, the corridor is where everyone will be, and the open door fills it with the smoke that kills most.
Cardboardunder the lights
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Back exitchained
A warehouse stacks flattened cardboard against the wall under the lights, and chains the back fire exit shut at night to stop theft. Which of fire's three needs has been added, and what has been taken away?
Only the fuel. The exit does not matter at night.
Not yet. Night is when a fire has the longest to grow unnoticed, and when the few people there most need a second way out. The chain is the deadlier of the two mistakes.
Fuel has been added next to a heat source, and a way out has been taken away.
Right. The cardboard is fuel under a heat source, which is two legs of the fire placed together. The chained exit takes away one of the two routes the plan depends on, at the time of day the fewest people are there to notice a fire start.
Nothing. Cardboard is not flammable until it is lit.
Not yet. Cardboard under a hot light is fuel waiting for heat it is already next to. That is what flammable means.
Lesson complete
A fire needs heat, fuel and air; take one away and it stops. The smoke kills before the flames do.