- Why does fire burn up?
- What fire needs to burn?
- Can fire burn itself?
- Is nitrogen more flammable than oxygen?
- How do fire start?
- What can not burn in a fire?
- Will Oxygen burn by itself?
- What is the best Defence against fire?
- What percent of oxygen is required for normal breathing?
- Why does water put out fire?
- What are the 4 stages of fire?
- Why is oxygen required for burning?
- What happens to oxygen in a fire?
- What percentage of oxygen is flammable?
- What are the 5 stages of fire?
- Can pure oxygen explode?
- How did Stone Age man make fire?
Why does fire burn up?
On Earth, gravity determines how the flame burns.
All the hot gases in the flame are much hotter (and less dense) than the surrounding air, so they move upward toward lower pressure.
This is why fire typically spreads upward, and it’s also why flames are always “pointed” at the top..
What fire needs to burn?
Oxygen, heat, and fuel are frequently referred to as the “fire triangle.” Add in the fourth element, the chemical reaction, and you actually have a fire “tetrahedron.” The important thing to remember is: take any of these four things away, and you will not have a fire or the fire will be extinguished.
Can fire burn itself?
Fire is a chemical process requiring three things to occur: oxygen, fuel and an ignition source. Without one of these factors, a fire can’t start or will burn itself out. … When a fire burns, a process called oxidation occurs, the same process that causes metal to rust.
Is nitrogen more flammable than oxygen?
Air is mostly nitrogen, which is not flammable. After nitrogen, the most abundant gas in our air is oxygen. Here’s where it gets complicated: Oxygen is also not flammable, but it is a high-energy gas that very readily oxidizes other materials.
How do fire start?
Fires start when a flammable or a combustible material, in combination with a sufficient quantity of an oxidizer such as oxygen gas or another oxygen-rich compound (though non-oxygen oxidizers exist), is exposed to a source of heat or ambient temperature above the flash point for the fuel/oxidizer mix, and is able to …
What can not burn in a fire?
What can’t be burned in a fire nor drowned in water? Ice. It melts instead of burning in a fire and it floats in water.
Will Oxygen burn by itself?
High concentrations of oxygen used during surgeries are a potential fire hazard for patients, but that doesn’t mean the O2 gas itself catches fire. Oxygen makes other things ignite at a lower temperature, and burn hotter and faster. … But oxygen itself does not catch fire.”
What is the best Defence against fire?
Your best defense against fire damage is to ensure that staff knows what to do in the event of a fire so they can respond quickly….All employees must know:Where exits and fire alarm pull stations are located.Evacuation routes.Where fire extinguishers and fire hoses are located.How to use extinguishers and fire hoses.
What percent of oxygen is required for normal breathing?
19.5 percentHumans need oxygen to live, but not as much as you might think. The minimum oxygen concentration in the air required for human breathing is 19.5 percent.
Why does water put out fire?
Water cools and smothers the fire at the same time. It cools it so much that it can’t burn anymore, and it smothers it so that it can’t make any more of the oxygen in the air explode. You can also put out a fire by smothering it with dirt, sand, or any other covering that cuts the fire off from its oxygen source.
What are the 4 stages of fire?
Compartment fire development can be described as being comprised of four stages: incipient, growth, fully developed and decay (see Figure 1). Flashover is not a stage of development, but simply a rapid transition between the growth and fully developed stages.
Why is oxygen required for burning?
So if we have carbon and we oxidize it to form carbon dioxide, the reaction of carbon with oxygen will release a lot of energy in the form of heat. Therefore, oxygen is necessary for burning because that is how we define burning.
What happens to oxygen in a fire?
Fire does use oxygen when it burns. But it also produces carbon dioxide. An oxygen molecule has two oxygen atoms in it. Fires use this to produce carbon dioxide by adding a single carbon atom from the fire’s fuel (wood, for instance).
What percentage of oxygen is flammable?
Dangers of Oxygen and Flammable Gases The second alarm is for when the oxygen levels get too high; usually 24%. When oxygen levels are high things become much more combustible so items such as clothes which may normally smoulder would just burst into flames.
What are the 5 stages of fire?
fire investigation – The five stages of fire growth are incipient free burning flashover post flashover and decay The incipient phase is characterized | Course Hero.
Can pure oxygen explode?
It may be hard to believe, but oxygen can also be dangerous. The dangers are fire and explosion. … Pure oxygen, at high pressure, such as from a cylinder, can react violently with common materials such as oil and grease. Other materials may catch fire spontaneously.
How did Stone Age man make fire?
We do not have firm answers, but they may have used pieces of flint stones banged together to created sparks. They may have rubbed two sticks together generating enough heat to start a blaze. Conditions of these sticks had to be ideal for a fire. The earliest humans were terrified of fire just as animals were.