What does the term “backdraft” refer to in firefighting?

The term "backdraft" specifically refers to a dangerous phenomenon in firefighting where an explosive burst of fire occurs when oxygen suddenly re-enters an oxygen-depleted environment. This situation typically arises in a confined space where a fire has consumed most of the oxygen, creating a vacuum. When a door or window is opened, it can allow fresh oxygen to rush in, igniting the accumulated combustibles and leading to a rapid and explosive combustion event.

Understanding backdraft is critical for fire responders because it highlights the importance of ventilation strategies during firefighting operations. Proper tactics can help prevent a backdraft situation from causing harm to firefighters and civilians. Other options describe different fire phenomena but do not accurately define backdraft.