Stages of fire
There are four stages of fire like ignition, growth, fully developed and burnout.
Ignition: At this Initial stage, a fire extinguisher can control the fire. The selection criteria of fire extinguisher is depends on fuel.
Growth: The growth of fire is increase due to additional fuel ignites.
Fully developed: At this stage the damage is cause due to increasing the temperature above threshold level.
Burnout: At this stage, concentration amount of fuel reduce. Due to that the fire gets less intense.
In order to select the right type of extinguisher to put out a fire, you must understand the different modes of fires or classes of fires.