Tetrahedron fire theory

There are three basic theories that are used to describe the reaction known as fire. They are the fire triangle, the tetrahedron of fire, and the life cycle of fire. Of the three, the first is the oldest and best known, the second is accepted as more fully explaining the chemistry of fire, while the third is a more detailed version of the fire triangle. Each is briefly described below. 

The second popular explanation of fire is the tetrahedron theory which is illustrated in Figure 1. This theory encompasses the three concepts in the fire triangle theory but adds a fourth side to the triangle, making it a pyramid, or tetrahedron this fourth side is called the chain reaction of burning. This theory states that when energy is applied to a fuel like a hydrocarbon, some of the carbon-to-carbon bonds break, leaving an unpaired electron attached to one of the... 

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