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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.
How does fire happen?
Fire occurs whenever combustible fuel in the presence of oxygen at an extremely high temperature becomes gas. Flames are the visual indicator of the heated gas. Fire can also occur from lower-temperature sources. Over time, combustible materials such as smoldering embers can reach their ignition temperature.
What must happen for a fire to occur quizlet?
Oxygen, heat, fuel, a self sustained chemical chain reaction. Each element must be in place for flaming combustion to occur.
What causes fire to burn?
Fire is the result of applying enough heat to a fuel source, when you’ve got a whole lot of oxygen around. As the atoms in the fuel heat up, they begin to vibrate until they break free of the bonds holding them together and are released as volatile gases.
How do you explain fire to a child?
Fire is a chemical reaction that releases light and heat. Substances combine with oxygen in the air, combusting with a flame and often smoke. Fires require fuel, oxygen and heat to burn. Different types of fuel include coal, oil and wood.
What three elements must be present for a fire to occur quizlet?
1 . According to the Fire Triangle, there are three elements that make up a fire. They are: FUEL, OXYGEN and HEAT.
What are the four stages of fire development?
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.
Which of the following components must be present for a fire to ignite and continue burning quizlet?
The fire ignition triangle describes the elements necessary for starting a fire: oxygen, heat, and fuel. All three must be present: Oxygen (air) – to start and sustain combustion. Air supply can be increased by windy conditions.
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 water?
Because water cannot burn, fires cannot burn from within water, there is no ready supply of oxygen in a bucket of water (though, of course, there is oxygen in the air above the water) and thus, the water extinguishes the fire.
Does fire need burning air?
Three things are required in proper combination before ignition and combustion can take place—Heat, Oxygen and Fuel. There must be Fuel to burn. There must be Air to supply oxygen. There must be Heat (ignition temperature) to start and continue the combustion process.
How hot is a fire?
Deep red fire is about 600-800° Celsius (1112-1800° Fahrenheit), orange-yellow is around 1100° Celsius (2012° Fahrenheit), and a white flame is hotter still, ranging from 1300-1500 Celsius (2400-2700° Fahrenheit). A blue flame is the hottest one of all, ranging from 1400-1650° Celsius (2600-3000° Fahrenheit).
How does fire start answer?
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.
Which of the following elements are required for sustaining a fire quizlet?
Fuel, air, and heat. Model of the four elements/conditions required to have a fire. The four sides of the tetrahedron represent fuel, heat, oxygen, and chemical chain reaction. Must have all four elements to be self sustaining.
What is the most important element of fire triangle?
The first element in the fire triangle is heat, which is perhaps the most essential of fire elements. A fire cannot ignite unless it has a certain amount of heat, and it cannot grow without heat. The fire triangle’s three sides represent heat, fuel and oxidization.
How are fires organized into classes?
Fire is divided into five classes (A, B, C, D, and K) that are primarily based on the fuel that is burning. This classification system helps to assess hazards and determine the most effective type of extinguishing agent.
What are the dynamics of fire?
Fire Dynamics is the study of how chemistry, fire science, material science and the mechanical engineering disciplines of fluid mechanics and heat transfer interact to influence fire behavior. In other words, Fire Dynamics is the study of how fires start, spread and develop.
What are the 7 factors that affect fire development?
SOIL HEATING, TEMPERATURE, AND TRANSFER. Rate of burning and heat output for surface and crown fires are influenced by fuel load, fuel moisture, topography, ignition method, air temperature, wind, and relative humidity.
What are the 5 stages of fire?
To help minimise the risk to your building during a fire, check out our fire protection services. Incipient. An incipient fire is a flame that is still in its beginning stage. Growth. As we move through the phases of a fire, we come to the second stage – growth. Fully Developed. Decay. Prevention in Your Building.
Why must Firefighters use tactics that control the oxygen available to the fire when they advance a hoseline through a door or ventilate windows?
Why must firefighters use tactics that control the oxygen available to the fire when they advance a hoseline through a door or ventilate windows? Firefighters working in the exhaust portion of the flow path will: feel a decrease in temperature as air is entrained by the fire.
Which class of fire extinguisher is to be used for electrical fires?
Class C – Fires involving energized (live) electrical equipment such as motors, appliances, or power tools.
What type of fuel is involved in a Class B fire?
Class B: Flammable liquids such as alcohol, ether, oil, gasoline and grease, which are best extinguished by smothering.
Why do we need fire?
Fire removes low-growing underbrush, cleans the forest floor of debris, opens it up to sunlight, and nourishes the soil. Reducing this competition for nutrients allows established trees to grow stronger and healthier. Fire clears the weaker trees and debris and returns health to the forest.
