A Bunsen burner flame is a mixture of gas and air. A Bunsen burner is a piece of laboratory equipment that can be used to create a continuous flame by controlling the mixture of gas and air.
The mixture of gas and air is controlled manually so that temperature, intensity and the size of the flame can all be adjusted as necessary. When the Bunsen burner collar is completely closed, there is a safety flame. The general purpose of a safety flame is to signal that the burner is on. As the collar opens, there is a blue outer flame and a blue inner flame. The blue outer flame is hotter than the safety flame. The blue inner flame is the hottest of all three flames.